If you go back to the beginning of the thread you will see the steam plant
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well im new here. but i just went through your entire build so far and i am amazed. i cant believe the detail you are putting into this boat. are there any more updates on it recently? i really wana see this get finished.Comment
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Hi rebels10, firstly a warm welcome to the Scale Models Forum. I'm glad you enjoyed reading through the build thread of the Ben Ain, as you can imagine it took a lot of putting together so it's always satisfying to know that someone has enjoyed reading it.
Unfortunately it is a bit of a long termproject as I work away from home for periods of three months at a time so not a lot gets done in that time. I do try to take small parts away with me to progress the project bt the last two times I have been away I have been scratch building the ships boats from wooden strip. I did quite an in depth write up on the work which I have since submitted to Model Boat magazine as an article, which was accepted and will be published later this year. This means that I cannot post the threads on here until after it has been published so the build thread hasn't had much in the way of additions recently. I am progressing the rest of the model though and I will be adding to the thread when I go back to work in a few weeks time.Comment
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Once again as the model progressed it became apparent that more aspects of the engineering required attention. The first concern was that the safety valve was still located at the front of the boiler and, although I was prepared to remove this along with the pressure gauge before removing or replacing the boiler in the model my concern was where the steam would escape should the valve ever lift. Consequently I wanted to move the safety valve back towards the funnel where it could then be easily arranged to vent into the funnel space. The problem was again a lack of available spare fittings on the boiler and I particularly did not want to move the main steam stop valve off the boss it was screwed into.
After considering many possible combination units of a home made valve assembly incorporating the safety valve I came up with the very simple idea of making a connecting piece that would mount both the existing main stop valve and the safety valve. The mounting was to consist of a female to female connector with a screwed conical fitting silver soldered into it. I drilled the side of the connector to suit the cone of the screwed fitting which would locate the piece as well as give additional strength to the joint. The screwed fitting was arranged at such an attitude as to give the required angle to the main stop valve when it was fitted and the connection was silver soldered to give a neat and strong joint. This fitting now screws into the available boss on the boiler via a threaded connection and the safety valve simply screws into the available top of the fitting. The main stop valve connects to the screwed fitting and the steam outlet pipe reconnected to the valve.
The other significant modification was the filling arrangement for the on board gas tank. I have always had a particular dislike for the ‘Ronson’ type filling valves, be they fitted to a cigarette lighter or a model gas tank. When you think about it all you are doing is inverting the purchased gas canister to allow liquid to flow then using the fitting on the canister you are opening the Ronson valve to allow the liquid to flow into the on board tank. The problem is if liquid is to flow into the tank then the displaced gas must be allowed to escape somehow. Because this does not happen the liquid is constantly spitting and blowing out as gas is trying to escape through the open valve at the same time as the liquid is flowing in. I have already modified the filling arrangement for the tank by filling through a clear hose into another valve and it quickly became obvious that the liquid would not flow very easily as the displaced gas could not escape.
To resolve this the Ronson valve was removed, at which point I noticed with surprise that the valve was not fitted with a dip tube, and the boss was drilled and tapped to accept a 5/16th x 32 tpi standard 90 degree globe valve to which a dip tube had been fitted. The idea of this valve is three fold, firstly it allows gas to escape at a controlled rate while liquid is flowing into the tank, secondly when liquid is seen spitting out of the valve you then know that the tank is full of liquid and finally the dip tube guarantees a liquid level and hence a gas space in the tank, thereby ensuring that the tank is never completely full of liquid and hence liable to being hydraulically locked.
I tried out the new valve with my camping gas canister, filling through the valve that had been used in the past with the new valve very slightly cracked open. I was surprised at just how much more quickly the liquid was seen to flow through the clear hose so obviously allowing the liquid to displace the gas worked well. After a few minutes liquid was seen spitting from the valve so at that point I knew that liquid was at the level of the dip tube so I stopped filling. Simple, effective, considerably safer and a lot quicker than using the Ronson valve so I was very pleased with the modification. The valve will be plumbed into an overboard pipe to ensure that a build up of gas inside the hull does not occur, making the arrangement considerably safer than the original.
The final modification was the fitting of a new speed regulating valve on the engine. The existing valve with the aluminium body has been attended to on a number of occasions and, although improvements have been noted it still seems to insist on leaking from the valve face. Modifications such as fitting a brass running face had limited success but one came loose and one became blocked with the araldite used to fit it!! The only real solution was to manufacture a brass bodied valve and a good friend, who happens to be a superb model engineer, helped out by making a beautiful perfect copy of the aluminium body in brass. This was fitted to the engine and run on the bench before putting back in the model and proved to be a huge improvement on the original arrangement. The valve still leaks slightly in the neutral position but it is significantly better and when the plant is removed again a bit more attention should improve it even more.
With the new modifications in place it was time to give the plant another couple of runs in the model to get a bit more of a feel for how the plant is operating. The boiler was filled from the feed tank, the separator tank emptied, the lubricator filled and the gas tank filled with the new arrangement. The boiler was taken up to pressure, the gas regulating valve turned on and the engine run, using the normal servo’s and control system. This was actually the first opportunity to observe the effect of the heat shunt, fitted to the separator and the gas tank to offset the effects of the gas cooling, and it surprisingly worked very well. After the engine had been running for approximately 10-15 minutes the pressure in the gas tank was noted as rising from 25 psi initially to 50 psi with no discernable affect on the burner performance so the heat shunt was obviously doing it’s job, as is the pressure regulating valve fitted to control the varying tank pressure. The only remaining concern from a technical point of view is the tendency for the steam exhaust to spit water out of the top of the funnel. This is obviously as a result of the fact that the separator tank is actually further away from the engine outlet than the ideal bit it is hoped that when the pipe work is completely lagged that this will improve significantly.
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Comment
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Once again as the model progressed it became apparent that more aspects of the engineering required attention. The first concern was that the safety valve was still located at the front of the boiler and, although I was prepared to remove this along with the pressure gauge before removing or replacing the boiler in the model my concern was where the steam would escape should the valve ever lift. Consequently I wanted to move the safety valve back towards the funnel where it could then be easily arranged to vent into the funnel space. The problem was again a lack of available spare fittings on the boiler and I particularly did not want to move the main steam stop valve off the boss it was screwed into.
After considering many possible combination units of a home made valve assembly incorporating the safety valve I came up with the very simple idea of making a connecting piece that would mount both the existing main stop valve and the safety valve. The mounting was to consist of a female to female connector with a screwed conical fitting silver soldered into it. I drilled the side of the connector to suit the cone of the screwed fitting which would locate the piece as well as give additional strength to the joint. The screwed fitting was arranged at such an attitude as to give the required angle to the main stop valve when it was fitted and the connection was silver soldered to give a neat and strong joint. This fitting now screws into the available boss on the boiler via a threaded connection and the safety valve simply screws into the available top of the fitting. The main stop valve connects to the screwed fitting and the steam outlet pipe reconnected to the valve.
The other significant modification was the filling arrangement for the on board gas tank. I have always had a particular dislike for the ‘Ronson’ type filling valves, be they fitted to a cigarette lighter or a model gas tank. When you think about it all you are doing is inverting the purchased gas canister to allow liquid to flow then using the fitting on the canister you are opening the Ronson valve to allow the liquid to flow into the on board tank. The problem is if liquid is to flow into the tank then the displaced gas must be allowed to escape somehow. Because this does not happen the liquid is constantly spitting and blowing out as gas is trying to escape through the open valve at the same time as the liquid is flowing in. I have already modified the filling arrangement for the tank by filling through a clear hose into another valve and it quickly became obvious that the liquid would not flow very easily as the displaced gas could not escape.
To resolve this the Ronson valve was removed, at which point I noticed with surprise that the valve was not fitted with a dip tube, and the boss was drilled and tapped to accept a 5/16th x 32 tpi standard 90 degree globe valve to which a dip tube had been fitted. The idea of this valve is three fold, firstly it allows gas to escape at a controlled rate while liquid is flowing into the tank, secondly when liquid is seen spitting out of the valve you then know that the tank is full of liquid and finally the dip tube guarantees a liquid level and hence a gas space in the tank, thereby ensuring that the tank is never completely full of liquid and hence liable to being hydraulically locked.
I tried out the new valve with my camping gas canister, filling through the valve that had been used in the past with the new valve very slightly cracked open. I was surprised at just how much more quickly the liquid was seen to flow through the clear hose so obviously allowing the liquid to displace the gas worked well. After a few minutes liquid was seen spitting from the valve so at that point I knew that liquid was at the level of the dip tube so I stopped filling. Simple, effective, considerably safer and a lot quicker than using the Ronson valve so I was very pleased with the modification. The valve will be plumbed into an overboard pipe to ensure that a build up of gas inside the hull does not occur, making the arrangement considerably safer than the original.
The final modification was the fitting of a new speed regulating valve on the engine. The existing valve with the aluminium body has been attended to on a number of occasions and, although improvements have been noted it still seems to insist on leaking from the valve face. Modifications such as fitting a brass running face had limited success but one came loose and one became blocked with the araldite used to fit it!! The only real solution was to manufacture a brass bodied valve and a good friend, who happens to be a superb model engineer, helped out by making a beautiful perfect copy of the aluminium body in brass. This was fitted to the engine and run on the bench before putting back in the model and proved to be a huge improvement on the original arrangement. The valve still leaks slightly in the neutral position but it is significantly better and when the plant is removed again a bit more attention should improve it even more.
With the new modifications in place it was time to give the plant another couple of runs in the model to get a bit more of a feel for how the plant is operating. The boiler was filled from the feed tank, the separator tank emptied, the lubricator filled and the gas tank filled with the new arrangement. The boiler was taken up to pressure, the gas regulating valve turned on and the engine run, using the normal servo’s and control system. This was actually the first opportunity to observe the effect of the heat shunt, fitted to the separator and the gas tank to offset the effects of the gas cooling, and it surprisingly worked very well. After the engine had been running for approximately 10-15 minutes the pressure in the gas tank was noted as rising from 25 psi initially to 50 psi with no discernable affect on the burner performance so the heat shunt was obviously doing it’s job, as is the pressure regulating valve fitted to control the varying tank pressure. The only remaining concern from a technical point of view is the tendency for the steam exhaust to spit water out of the top of the funnel. This is obviously as a result of the fact that the separator tank is actually further away from the engine outlet than the ideal bit it is hoped that when the pipe work is completely lagged that this will improve significantly.
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Comment
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One part of any such project that seems to progress in the background alongside everything else yet remains a separate and independent item is the electrical installation and in particular the lighting.
I decided right from the start that I wanted to incorporate a lighting system but did not pay a great deal of attention as to how I wanted to arrange this when I first started building. The one decision that I did make however was what type of lamps to use. I could have gone for the simple and reliable path of LED’s but for a 1920’s coaster which would almost certainly be using oil lamps I thought the bright blue light from an LED would not be an appropriate light. The best way to achieve the type of light I was after was to use 12v incandescent lamps but use a lower voltage across them. This would have the advantage of producing a dimmer light, more in keeping with the model’s age, and it would also hugely increase the life of the lamps. This was to be particularly significant as I was going to seal the lamps in for the life of the model. This being mainly driven by the fact that a number of lights were to be in locations that access could not possibly be achieved after the model was completed.
Initial experiments tended to indicate that a six volt pack would produce the required degree of illumination so a simple four “AA” pack battery holder would be perfect for the job. The lamps seemed to be suitably bright enough so I started to install the initial lamps in the hull as the building progressed.
I have always believed in completely encasing wiring for lamps such as this in a resin to protect the wiring for the life of the model and the lamps were arranged to be located in a reflective housing to protect them and to enable the best from the lamp. I therefore started to install lamps in the hull inside paint pot lids and ran the cables back to a central location for connecting at a later date. Lamps were fitted behind the ports in the fo’c’sle, behind the ports in the mid ship hull and were incorporated into the bridge unit and the aft accommodation unit.
The lamps in the aft accommodation were a bulkhead lamp fitting with the 3v lamps removed and 12v lamps fitted instead to give a similar level of illumination. Other lights fitted during the build included the red and green bridge navigation lamps, which were turned brass items with a thin acetate sheet fitted over the opening after the insides had been painted. The lamp itself was painted up to resemble painted copper with some of the paint chipped and a degree of weathering added before putting another 12v lamp inside after feeding the cables up through the back of the bridge housing.
Once the aft accommodation lamps had been fitted the whole concept of how I wanted to operate the lights had to be addressed and decided before taking the model any further. I was particularly after a level of realism in the use of the lights so consequently I wanted separate circuits for separate uses. I decided on one circuit for all navigation lights so the two bridge navigation lamps, the aft anchor lamp and the forward mast lamp were to be connected together. All accommodation lighting was to be common and independently switched so that the ship could be alongside without navigation lights but with accommodation lights and finally the light on the bridge had to be independent. Bridge lights are very rarely lit except when in port so I particularly did not want the bridge light to be lit when the ship was underway. This therefore gave me three circuits, more than enough for such a simple old steamer!
The next decision was whether I wanted the circuits to be operated via the transmitter or manually. Part of this decision was based on the fact that using a Dx6i meant that I would be switching lighting circuits with a proportional channel, which didn’t seem right, as well as requiring either servo’s and switches or electronic relay’s to operate the circuits. All more complexity and weight in the model. Consequently I opted for the circuits to be operated manually from switches located in the main hatch. Obviously you don’t then have the convenience of switching circuits on and off when the model is under way but I thought that was a price I was prepared to pay for the sake of keeping the internals that bit simpler. I think I have enough complexity in the steam plant without going down the same path with the lighting circuits as well!
It was also at this point when I decided to use rechargeable batteries for the lights so fitted four “AA” rechargeable batteries in the holder. Then I noticed that the lamps were now getting too dim for credibility and then realised of course that four rechargeable “AA”s only gives 4.8 volts. Time for a rethink. The solution was to go for a 7.2 pack, which I tried but thought that the lights were too bright so eventually removed a cell and settled on a 6V 5 cell rechargeable pack. This was partly dictated by the fact that the lighting battery is also supplying the gas control valve and 7.2 v proved to be two much and the servo did not operate smoothly so consequently the 6v pack seemed to be the best compromise all round. A charging connection was also fitted to enable a normal Tamiya type charger to be used to charge up the battery pack with all items remaining in place in the model.
Having decided on the circuits and power the final main decision was how to get the power to the removable items such as the bridge and the aft accommodation units. I have always particularly disliked the idea of trying to disconnect wires from connecting blocks to enable parts of a model to be removed and have recently tried the method of plugging cables into a socket located within the model but for this I really wanted the complete convenience of being able to remove and replace the parts of the model without having to become involved in the lighting at all. The only way I could see this happening was by using a plug and socket connector unit with one being permanently mounted in the removable unit and the other being mounted in the model. I eventually obtained some very neat little six pin plug and socket units and set about how I was going to mount them in the model. I only used the centre four pins as I only needed two circuits to be completed so the connectors were wired up and mounted in holders ready to fit. First the unit was fitted in the removable aft accommodation section and, when set, the plug was assembled.
Then the accommodation was placed on the model and the other side of the plug glued to a mounting inside the aft coaming. It actually proved to work very successfully with the circuit being made when the accommodation is dropped in place which can also be removed without worrying about any of the lighting circuits. The two circuits were then tested and the accommodation lights and the aft anchor light worked fine from the two switches in the main hatch.
All that remains is to fit exactly the same plug and socket unit below the bridge for the two circuits in that piece!
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Comment
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One part of any such project that seems to progress in the background alongside everything else yet remains a separate and independent item is the electrical installation and in particular the lighting.
I decided right from the start that I wanted to incorporate a lighting system but did not pay a great deal of attention as to how I wanted to arrange this when I first started building. The one decision that I did make however was what type of lamps to use. I could have gone for the simple and reliable path of LED’s but for a 1920’s coaster which would almost certainly be using oil lamps I thought the bright blue light from an LED would not be an appropriate light. The best way to achieve the type of light I was after was to use 12v incandescent lamps but use a lower voltage across them. This would have the advantage of producing a dimmer light, more in keeping with the model’s age, and it would also hugely increase the life of the lamps. This was to be particularly significant as I was going to seal the lamps in for the life of the model. This being mainly driven by the fact that a number of lights were to be in locations that access could not possibly be achieved after the model was completed.
Initial experiments tended to indicate that a six volt pack would produce the required degree of illumination so a simple four “AA” pack battery holder would be perfect for the job. The lamps seemed to be suitably bright enough so I started to install the initial lamps in the hull as the building progressed.
I have always believed in completely encasing wiring for lamps such as this in a resin to protect the wiring for the life of the model and the lamps were arranged to be located in a reflective housing to protect them and to enable the best from the lamp. I therefore started to install lamps in the hull inside paint pot lids and ran the cables back to a central location for connecting at a later date. Lamps were fitted behind the ports in the fo’c’sle, behind the ports in the mid ship hull and were incorporated into the bridge unit and the aft accommodation unit.
The lamps in the aft accommodation were a bulkhead lamp fitting with the 3v lamps removed and 12v lamps fitted instead to give a similar level of illumination. Other lights fitted during the build included the red and green bridge navigation lamps, which were turned brass items with a thin acetate sheet fitted over the opening after the insides had been painted. The lamp itself was painted up to resemble painted copper with some of the paint chipped and a degree of weathering added before putting another 12v lamp inside after feeding the cables up through the back of the bridge housing.
Once the aft accommodation lamps had been fitted the whole concept of how I wanted to operate the lights had to be addressed and decided before taking the model any further. I was particularly after a level of realism in the use of the lights so consequently I wanted separate circuits for separate uses. I decided on one circuit for all navigation lights so the two bridge navigation lamps, the aft anchor lamp and the forward mast lamp were to be connected together. All accommodation lighting was to be common and independently switched so that the ship could be alongside without navigation lights but with accommodation lights and finally the light on the bridge had to be independent. Bridge lights are very rarely lit except when in port so I particularly did not want the bridge light to be lit when the ship was underway. This therefore gave me three circuits, more than enough for such a simple old steamer!
The next decision was whether I wanted the circuits to be operated via the transmitter or manually. Part of this decision was based on the fact that using a Dx6i meant that I would be switching lighting circuits with a proportional channel, which didn’t seem right, as well as requiring either servo’s and switches or electronic relay’s to operate the circuits. All more complexity and weight in the model. Consequently I opted for the circuits to be operated manually from switches located in the main hatch. Obviously you don’t then have the convenience of switching circuits on and off when the model is under way but I thought that was a price I was prepared to pay for the sake of keeping the internals that bit simpler. I think I have enough complexity in the steam plant without going down the same path with the lighting circuits as well!
It was also at this point when I decided to use rechargeable batteries for the lights so fitted four “AA” rechargeable batteries in the holder. Then I noticed that the lamps were now getting too dim for credibility and then realised of course that four rechargeable “AA”s only gives 4.8 volts. Time for a rethink. The solution was to go for a 7.2 pack, which I tried but thought that the lights were too bright so eventually removed a cell and settled on a 6V 5 cell rechargeable pack. This was partly dictated by the fact that the lighting battery is also supplying the gas control valve and 7.2 v proved to be two much and the servo did not operate smoothly so consequently the 6v pack seemed to be the best compromise all round. A charging connection was also fitted to enable a normal Tamiya type charger to be used to charge up the battery pack with all items remaining in place in the model.
Having decided on the circuits and power the final main decision was how to get the power to the removable items such as the bridge and the aft accommodation units. I have always particularly disliked the idea of trying to disconnect wires from connecting blocks to enable parts of a model to be removed and have recently tried the method of plugging cables into a socket located within the model but for this I really wanted the complete convenience of being able to remove and replace the parts of the model without having to become involved in the lighting at all. The only way I could see this happening was by using a plug and socket connector unit with one being permanently mounted in the removable unit and the other being mounted in the model. I eventually obtained some very neat little six pin plug and socket units and set about how I was going to mount them in the model. I only used the centre four pins as I only needed two circuits to be completed so the connectors were wired up and mounted in holders ready to fit. First the unit was fitted in the removable aft accommodation section and, when set, the plug was assembled.
Then the accommodation was placed on the model and the other side of the plug glued to a mounting inside the aft coaming. It actually proved to work very successfully with the circuit being made when the accommodation is dropped in place which can also be removed without worrying about any of the lighting circuits. The two circuits were then tested and the accommodation lights and the aft anchor light worked fine from the two switches in the main hatch.
All that remains is to fit exactly the same plug and socket unit below the bridge for the two circuits in that piece!
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Nice work mate, what do you use to do your rivits, i use a fine oiler bottle but am always open to new techniques.Originally posted by \
AndyComment
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After a number of experiments with various glues on a piece of scrap I eventually came to the conclusion that Super Glue gel was the best. Squeezing those small bottles to death though for days on end doesn't half make your hands ache!!
One thing I did learn as well was the fact that the gel soaks into the surface of fibre glass and doesn't leave a bead when dry so you have to prime the surface first with a spray primer and then the gel beads fine.Comment
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Having made the modifications to the steam plant in Chapter 12 it was time to make the most of them and finally get the flue sorted out.
The whole idea of moving the safety valve closer to the funnel was to enable me to vent the safety valve up through the funnel rather than have it lifting and venting inside the model, which could have made a bit of a mess inside, so now it was time to make the arrangement to allow this. My idea had always been to make a pipe from a cover that went over the safety valve and pipe it into the boiler flue so I set about having a good root through all the copper pipe fittings in B&Q to see what I could use. I was very pleasantly surprised to come across a copper fitting that was a 45 degree bend with a flared end that sat very nicely over the safety valve body. I didn’t want to actually attach it to the valve but simply have the new pipe sat over it, which would enable me to gain access to the valve reasonably simply by removing the flue from the boiler. Then I sourced a piece of copper pipe that slid nicely into the other end of the fitting from the scrap bin at work and I had the bits to start with.
The first thing I wanted to do was to secure the steam exhaust pipe running up the centre of the flue to prevent it from rattling around while I worked on the new pipe so I looked through my metal bits and bobs and came up with an old brass capstan arrangement. I drilled out the centre boss and then cut the main flue tube to length to suit the model funnel and cut notches around the circumference to match the arms of the capstan. The pieces were then assembled around the steam exhaust pipe with a plastic metal putty material to hold the whole assembly in place until it set. I had a play around with soldering the parts but it proved to be extremely difficult with the high number of pieces to be secured simultaneously as well as the significant difference in component size making for difficult heat transfer issues. The plastic metal putty method is certainly not quite as strong as solder but for an item such as this which is not taking any load it is perfectly adequate and enables complex assembly’s such as this to be put together easily. Once the putty had set the protruding ends were trimmed and the excess putty filed down to give a neat arrangement for holding the steam exhaust pipe centrally while having a minimum of effect on the flue cross sectional area.
Then it was time to fit the flue to the boiler in the model and mark out where the new safety valve vent was to fit. I wanted a smooth path for the safety valve outlet to minimise the possibility of a back pressure effect so it was important to have the pipe entering the flue at a shallow angle and ensure the steam did not vent back into the boiler furnace space. The copper fitting was held loosely in place on the valve, the pipe length determined and the entry point into the main flue was determined. The flue was then removed again and the penetration into the flue was started with a drilled hole. This was then opened out with a tapered reamer, which has the advantage of cutting on the edge so it could be held at the appropriate angle, and a suitable elliptical penetration was generated to fit the vent pipe. The vent was cut at a matching angle and to length before the pieces were assembled loosely again on the model to see how it all fit. Once again the challenge here was to ensure that the pieces were perfectly aligned so it really required securing while in place on the model so the plastic metal putty method was used to hold the bits together. Spacers were inserted around the various parts to ensure perfect alignment before placing small amounts of the putty around the joints to effectively ‘tack’ them in place. Once again there is no loading on the pieces, the pipe simply sits over the safety valve so I’m reasonably confident that the plastic metal putty will be up to the job. If it falls apart one day I’ll let you know. The assembly was removed again and the joints were completely sealed up with the putty to ensure a degree of strength.
Once the structure of the flue was completed it was time to lag the assembly and the most effective way of doing this was to wrap the components with string to give a neat and tidy covering, especially around the joint, before finishing off with a wrap of sticky backed foil tape. The final unit looks surprisingly realistic but more importantly I now have a flue that combines the boiler exhaust, the steam exhaust and the safety valve vent into a single pipe.
Interestingly the final thing to mention here is the fact that although I go on and on about pre-planning I fell foul of my own lack of it. I always thought that there was plenty of room inside the aft superstructure unit to accommodate the safety valve vent but I’d seriously got it wrong. The new vent pipe interfered significantly with the superstructure and I was incredibly lucky to be able to remove material from the inside of the unit without it being visible externally. Talk about a huge sigh of relief.
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Comment
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Having made the modifications to the steam plant in Chapter 12 it was time to make the most of them and finally get the flue sorted out.
The whole idea of moving the safety valve closer to the funnel was to enable me to vent the safety valve up through the funnel rather than have it lifting and venting inside the model, which could have made a bit of a mess inside, so now it was time to make the arrangement to allow this. My idea had always been to make a pipe from a cover that went over the safety valve and pipe it into the boiler flue so I set about having a good root through all the copper pipe fittings in B&Q to see what I could use. I was very pleasantly surprised to come across a copper fitting that was a 45 degree bend with a flared end that sat very nicely over the safety valve body. I didn’t want to actually attach it to the valve but simply have the new pipe sat over it, which would enable me to gain access to the valve reasonably simply by removing the flue from the boiler. Then I sourced a piece of copper pipe that slid nicely into the other end of the fitting from the scrap bin at work and I had the bits to start with.
The first thing I wanted to do was to secure the steam exhaust pipe running up the centre of the flue to prevent it from rattling around while I worked on the new pipe so I looked through my metal bits and bobs and came up with an old brass capstan arrangement. I drilled out the centre boss and then cut the main flue tube to length to suit the model funnel and cut notches around the circumference to match the arms of the capstan. The pieces were then assembled around the steam exhaust pipe with a plastic metal putty material to hold the whole assembly in place until it set. I had a play around with soldering the parts but it proved to be extremely difficult with the high number of pieces to be secured simultaneously as well as the significant difference in component size making for difficult heat transfer issues. The plastic metal putty method is certainly not quite as strong as solder but for an item such as this which is not taking any load it is perfectly adequate and enables complex assembly’s such as this to be put together easily. Once the putty had set the protruding ends were trimmed and the excess putty filed down to give a neat arrangement for holding the steam exhaust pipe centrally while having a minimum of effect on the flue cross sectional area.
Then it was time to fit the flue to the boiler in the model and mark out where the new safety valve vent was to fit. I wanted a smooth path for the safety valve outlet to minimise the possibility of a back pressure effect so it was important to have the pipe entering the flue at a shallow angle and ensure the steam did not vent back into the boiler furnace space. The copper fitting was held loosely in place on the valve, the pipe length determined and the entry point into the main flue was determined. The flue was then removed again and the penetration into the flue was started with a drilled hole. This was then opened out with a tapered reamer, which has the advantage of cutting on the edge so it could be held at the appropriate angle, and a suitable elliptical penetration was generated to fit the vent pipe. The vent was cut at a matching angle and to length before the pieces were assembled loosely again on the model to see how it all fit. Once again the challenge here was to ensure that the pieces were perfectly aligned so it really required securing while in place on the model so the plastic metal putty method was used to hold the bits together. Spacers were inserted around the various parts to ensure perfect alignment before placing small amounts of the putty around the joints to effectively ‘tack’ them in place. Once again there is no loading on the pieces, the pipe simply sits over the safety valve so I’m reasonably confident that the plastic metal putty will be up to the job. If it falls apart one day I’ll let you know. The assembly was removed again and the joints were completely sealed up with the putty to ensure a degree of strength.
Once the structure of the flue was completed it was time to lag the assembly and the most effective way of doing this was to wrap the components with string to give a neat and tidy covering, especially around the joint, before finishing off with a wrap of sticky backed foil tape. The final unit looks surprisingly realistic but more importantly I now have a flue that combines the boiler exhaust, the steam exhaust and the safety valve vent into a single pipe.
Interestingly the final thing to mention here is the fact that although I go on and on about pre-planning I fell foul of my own lack of it. I always thought that there was plenty of room inside the aft superstructure unit to accommodate the safety valve vent but I’d seriously got it wrong. The new vent pipe interfered significantly with the superstructure and I was incredibly lucky to be able to remove material from the inside of the unit without it being visible externally. Talk about a huge sigh of relief.Comment
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Richard:
I don't think "exhaustive" does justice for the sheer amount of your labor! Absolute precision that I'll never quite understand-its builds like yours that keeps me coming back here for more and more. I guess "it" keeps coming back if you work it! Sincerely, JeffComment
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Thanks Jeff, I have to admit I sometimes doubt my own sanity when I realise what I'm getting into but at the end of the day I enjoy it so that's the important bit.Comment
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Chapter Fifteen- The Boats
Part One
This section of the Ben Ain build was actually published as an independent article on building a clinker built boat in Model Boats Magazine in May 2009 and can still be purchased as a back issue from customer.services@myhobbystore.com
The Idea
Occasionally a challenge comes your way in your modeling that makes you stop and think, “Do I go for the easy option or do I embark on a whole new area of modeling and see what I can do to improve the final model?” I think as modelers we are always looking for new challenges and new skills to develop and so invariably enjoy coming across such opportunities during our projects. The actual original inspiration for this came from the boats that Bryan Young made for his General Havelock model and made me realize that I could do something a bit more individual.
Hence the decision not to use the supplied fibre-glass mouldings for the ships boats on my current steam coaster but to have a go at a scratch built clinker construction ships boat.
The idea was sound enough but as I had never put together anything “plank-on-frame” in my life I was, yet again, in for a very steep learning curve. The enthusiasm was initiated when I noticed a very nicely put together model at the Harrogate Engineering Show in May 2008 of a clinker built rowing boat and after a chat with the owner I took a few pictures and he very kindly produced the next day a set of rather old plans. The first obvious thing was that the proportions were different to those of the ships boat I wanted to make so after a lot of thinking and head scratching I decided to scale the plans to a different amount longitudinally than across the body plan. First of all I scaled the longitudinal section to 84% of the original then I scaled the body plan to 68% of the original giving me the correct proportions and external dimensions of the model boat I wanted to produce. I then had to complete the body plan by hand sketching the sections taller to compensate for the slightly higher longitudinal section but when finished it all appeared to work together as a useable plan.
My original idea for materials was to use veneer sheeting for the planking and so I started the project with cutting some veneer into thin strips and trying to bend it. The initial problems with cutting evenly dimensioned strips were assisted by use of a jig but I did find quite regularly that the blade would follow the grain and produce slightly varying widths of plank. The final direction though was decided when I tried to bend the veneer. No matter how long I kept it in hot water it still had a tendency to splinter at the edges and so I scrapped the idea of veneer and moved on to pre cut strips. I went for 5mm x 1mm pear planks, which proved to be easy enough to cut, bent well without splintering and was about the right colour I was after for the finished model which was going to be varnished internally and painted externally, as per most ships lifeboats and dinghies of the period of my steamer. I also decided on beech 4mm x 2mm strip wood for the keel, which did not require bending and which was strong and close grained to give the structure a bit of strength when the knees were laminated into it.
The Planking Jig
The first thing I did was to put together the keel along with it’s stern post, stem post, internal knees and the transom. The keel and posts were made from the longitudinal plan from 4mm x 2mm beech, which has a nice colour and is relatively strong with fine close grain for just this purpose. All the ends were rounded off according to the plan and a transom was made up from the body plan profiles of 5mm x 1mm pear planks, which will also be used for the planking, and glued in place across the stern post.The keel was necessary to get the planking jig set up correctly and helped ensure that the jig was going to be workable.
Next I prepared a wooden base with a centre line and glued beams of 5mm x 5mm lime at the relevant locations of the stations taken from the longitudinal section on my scaled plan. These would eventually locate the station profiles, cut from the body plan. Then I put together a main spine for the jig which I laminated from 0.030 thou plus 0.060 thou plasticard. This gave me a thickness of 0.090 thou, or 2.25mm, a perfect clearance for the 2mm beech keel. The main spine was cut to clear the station beams and shaped to fit the keel before adding a number of plates to locate the keel and posts correctly on the main spine. This is when it started to get a bit tricky and monotonous but well worth taking time and care to get this bit right. The scaled body plan was copied and each station profile was cut out, giving a paper template, which was then transferred to more of the 0.030 thou plasticard sheet. These station profiles were then carefully cut out and glued in identical pairs to either side to the beams on the base, ensuring that the tops were in line along the centre of the keel and they all followed the correct lines along the boat sides.
When this was all completed I finally had a planking jig with a keel and posts located in it and the serious job of planking the model could begin.
Planking
Being clinker construction the planking had to start at the keel so I started to work out a plan of action and to get it clear in my mind how the planks were going to be arranged. As I was using 5mm x 1mm pear planks I decided on an overlap of 1mm so the planks were going to be 4mm spaced around the midship section, which would require the widest planks. I then marked out the spacing on the profile edge with a black pen and worked out that I would need ten planks around the longest profile. This then had to equate to the length of the other profiles so I measured the forward and aft ones and divided the length, allowing for a suitable small amount of sheer at the top plank, into ten. This then gave me the width of the planks at either end at 4mm so my planks were going to taper from 5mm across the centre three profiles, then taper down to 4mm at the transom and the stem post. It all sounded good so time to start cutting some wood.
I marked out the keel strake plank, cut it to the appropriate taper and soaked it in hot water for ten minutes. I was then able to play it in my fingers to tease it into a reasonable shape as it cooled and dried, giving me a plank that actually sat on the jig reasonably close to the correct shape. The ends were going to have to be held in place when glued as they could not be bent sufficiently to fit but I was happy with the majority of the fit. It was at this point that my lack of experience showed itself when I came to glue down the first plank. I glued it only at the centre, allowed it to dry and then glued it further along it’s length when I realized that using 0.030 thou plasticard for the profiles did not enable me to hold the plank to them and ensure they remained in shape as the glue dried. I specifically used this material because it was easy to cut and shape and the wood glue would not adhere to it but the downside was that I could not use pins to hold the planks to the profiles while the glue set. My only option was to use a combination of masking tape and elastic bands to hold the planks down, which proved to be very tricky and meant that the planks had to be glued down in stages, making the process quite long winded. Still we live and learn and using wooden profiles would have been a lot more difficult to make.
Another part of the process to tackle as the plank was in the process of being fitted was the ends. At the transom the planks needed to be recessed into the edge of the transom to prevent ugly gaps being visible so before gluing the end down a sharp scalpel was used to cut a small tapered notch into the edge. This enabled the plank end to sit down correctly and the next plank will be able to sit on top of it without a gap showing. The fit at the stem post also proved to be a challenge and whilst trimming the ends to match the profile of the post was easy enough dealing with the overlap of the planks was not quite so straightforward. At this point in the construction I decided to leave the ends trimmed to suit the centre line of the post and see how the planks looked when they were all fitted.
From this point on it was simply a case of laying down individual planks, cut to the same tapers and using the same process of gluing at the centre edge then, when set, gluing down the tapered ends. It soon became apparent that the planks would develop a mind of their own when it came to lying flat so I soon realized that the 1mm overlap of each plank would have to be adjusted to suit the progression. The biggest challenge came at the change from the bottom to the sides where the plank running along the corner wanted to lie in an entirely different position to where I wanted it. It was also obvious that I was going to have to adjust the lay of the planks as they went up the sides to ensure that the final top plank laid at just the correct angle to give the shear I wanted from the transom to the bow. This is probably what makes a clinker built hull a good choice for a first timer to plank on frame construction as the lay of the planks can be adjusted slightly as they are fitted, unlike planks that are butted together which have to be a perfect fit. I also realized that the ten planks originally estimated was going to end up being eleven planks but the great beauty of a model of this nature is that no-one can say what is right or wrong. Eventually the planking was completed and the time came to remove the hull from the planking frame. It was actually quite a moment to see the inside of the hull for the first time and realize that it looked quite realistic.
Ribs
I had mistakenly assumed that the planking was going to be the time consuming part of this project but as I turned my attentions to the internal ribbing it soon became obvious that this was not going to be exactly easy either. The first challenge was what to make the ribs out of and my original experiments with bending cut up planks were not very successful. I also tried veneer again but that unfortunately was even less successful and it simply splintered when I tried to bend it as it had done in my initial experiments. Eventually I achieved a degree of success by cutting 1mm strips from the edge of the 5mm x 1mm pear planks, soaking them in hot water for 10 minutes and bending them around a former for consistency. This proved to be a lot more effective then bending them in my fingers and I simply had to hold the strips on the former until they cooled and partly dried out. Every now and then one would break or splinter but I achieved a reasonable success rate so I decided to use these 1mm x 1mm strips for the ribs. Applying the ribs was also tricky and time consuming and the best method I eventually came up with was to lay the curved rib in the hull with a suitable excess protruding above the hull and hold it in place in the middle with a piece of sticky tape. I could then place a few spots of glue along it to hold it to the internal planking and the excess could be used to help adjust the position until it was in just the right place. I did the ribs in pairs and started at the centre one and placed them simply by eye, ensuring that the pairs were perpendicular to the keel and evenly spaced from the previous rib. Starting in the centre ensured that any inaccuracies as I went along were minimized by travelling only half the length of the hull so I was able to eventually get the required number of ribs glued in place and I snipped the protruding ends off with a pair of fine electrical side cutters.
Once all the ribs were in place the next part was to fit the four longitudinal stringers, two either side, to locate the thwarts to called the thwart stringers and the two along the top referred to as the gunwale stringers. These were simply located in place with some low tack masking tape and spots of glue placed on the points where they rested on the ribs. When the glue was set the masking tape was removed and the remaining locating points were also glued. These stringers were also made from the 1mm x 1mm strips I had cut from the pear planks so all the internal structure was made of exactly the same wood.
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Part Two
Floor
The structure of the bottom boarding had to vary slightly from the original plan due to the fact that I had scaled the plan differently along it’s length and across the beam but my thoughts were that as long as I followed a similar structure and design to the plan it should look authentic when completed. I started by laying five transverse floors across the hull at the height I wanted the bottom boards to sit, ensuring that they remained level and used some more of the 5mm x 1mm planking rather than the scale equivalent which should really have been more 1mm x 1mm. This was for no other reason than I wanted a bit of strength here and the floors were hardly visible anyway below the bottom boards.
Then it was simply a case of cutting the bottom boards from more 5mm x 1mm pear, starting at the keel and working out and allowing for a realistic clearance around the edges. I put a joint across the model below the second thwart to make finishing the taper at the aft end that bit easier and cut neat clearances around where the keel knees penetrated the boards. I applied a couple of coats of satin polyurethane varnish to the internal surfaces of the internal planks up to the bottom board level as well as varnishing the relevant surfaces of the bottom boards before gluing them down to the floors. I then varnished the top surfaces of the bottom boards as well as the internal planking just above the board level to ensure that everything was perfectly sealed and protected up to that level.
Thwarts
The thwarts were not surprisingly made up of laminated 5mm x 1mm pear planks glued edge to edge in just the same way as I made the transom and so made up planks of 10mm x 1mm for those thwarts that required it. The thwarts were cut to shape and length with the two aft thwarts and the longitudinal seats made in situ to ensure a perfect fit at all the joints. When all the thwarts were finished they were glued in place across the thwart stringers after cutting the aft thwart to neatly fit around the stern post.
Knees and Rowlocks
At this point the main structure of the boat was finished but the little detail bits that seem to be just as time consuming as all the other work still remained. The plan called for a number of additional knees to be fitted to the thwarts and other parts of the structure and how to make these was something I needed to experiment with. I started by drilling holes into pieces of the 5mm x 1mm pear planks but couldn’t get it to cut cleanly enough so eventually I tried 5mm x 1mm lime and had more success with that. I drilled a hole of 4mm diameter through the centre of the plank then cut it across the diagonal before cutting the plank to suit at either end. This gave me a very good basis for the thwart knees so I made 12 of these, two as spares which I did need, and then dressed them up with fine grade wet and dry rolled into a small tube to round them to shape. These formed the thwart knees and were simply glued to the relevant thwarts and the side planking according to the plan.
The other knees located at either ends of the gunwale and across the thwart corners were made up individually from the pear planking and simply carefully carved and filed to shape before gluing in place. This all sounds a bit on the easy side now that I am describing it after the event but there were a number of failures before I got it right ad probably as well that I work in the garage out of earshot of anyone else! There is nothing more fiddly than sanding bits of wood only a couple of millimeters big.
The other remaining pieces of detail were the rowlocks and was one thing that I deviated from the plan for. The plan had very traditional thole pin type rowlocks but I had some white metal rowlocks included with the original steamer kit so I decided to use those as I decided that they were suitably period for the model. These could of course be simply scratch built from copper wire or wooden thole pins used, as was the case with the example I saw at Harrogate, but I cut and drilled six small blocks of the 4mm x 2mm beech, rounded them off and glued them to the top surface of the sanded down surface of the top plank, rib ends and gunwale stringer. I simply glued the rowlocks into these blocks and left them as a white metal finish, which will eventually be varnished over.
Painting
Much as it pained me to do so all the references I could find of ships of this period were fitted with boats that were painted white, be they either the lifeboats or the dinghies. Consequently for the model to remain authentic I had no alternative other than to paint the outside of the hull white and hide all that lovely woodwork. I masked off the top plank on the outside and around the internal surfaces and sprayed two light coats of acrylic car body grey primer. I wasn’t too bothered about the quality of the surface finish as I knew these boats were well used and the paint finish reflected this so the grey was only as a sealer and an indicator for the white. I then sprayed two light coats of white primer, trying not to over do it and spoil the available grain texture but once again getting an even matt coverage. Finally I brush painted white matt enamel over the primer. I particularly want to have all the finishes on this model to be brushed to reflect the way in which paint was applied at the time and using a small flat brush with a thick enamel paint allowed additional surface textures to be generated which will be enhanced by weathering at a later stage in the model.
Fittings
As they say “The Devil’s in the detail” and if I was making this model as a stand alone item in it’s own right I could well have called it a day at this point. I did however want to use it as part of the much larger steamer model and, as such, it had to fit into to atmosphere I want to create for this model. Consequently I wanted to add a few bits that would bring the model to life and give it the real appearance of a used piece of equipment.
Cover: There has been much debate over the years as regards the use of boat covers on ships of this type of period which has led me to believe that a lot of it was up to the captain or crew of the individual vessels. There is good reason to believe that covers were supplied but regularly left off for such reasons as allowing the wood to expand in wet conditions thereby keeping the caulking tight or simply because crews did not have the time or the inclination to fit the covers. I decided that obviously I wanted the internal detail of the dinghy model to be visible but assuming a cover would be supplied then it could well be found inside the boat itself. I therefore set about making a cover of approximately the right size and shape to fit the top of the boat out of metal foil tape with the gum removed by acetate thinners. When I had the shape I folded the metal foil as I assumed it would be folded off the boat and then shaped it to fit over one of the thwarts. The cover was then sprayed with acrylic grey primer before being painted up with matt green modeling enamel, which included some shading of the highlights and the shadows to give it a bit of realism. The cover was then glued to one of the thwarts.
Anchor: Almost certainly boats such as this would be fitted with a simple grappling anchor and so I made one up from domestic cable core, bent to shape, super glued together and fitted with a short length of chain from the bit box. This was then fitted with a suitable length of scale rope, looped over the lifting eye on the stem post and to the end of the chain. After a coat of matt metallic paint this passes as a suitably realistic anchor typical of the period and which would be quite likely to be found in the bottom of such a boat.
Oars: The most significant item of internal detail was the oars. Almost certainly stored in the boat itself and probably lashed to the thwarts or possibly on the bottom boards. I needed six oars if they were to look credible so I set about experimenting with some possibilities. I eventually found some small bamboo skewers in the kitchen, well they weren’t doing anything useful there, and cut a notch in a piece of the good old 5mm x 1mm pear to match the taper. These were glued together and, when set, the paddle was carved to resemble the correct shape and then sanded to blend it in with the skewer. I cut them to a suitable length and cut a handle in the end with a needle file in the lathe before giving them all two coats of varnish. The finishing touch was using small pieces of brown heat shrink to resemble the leather protective shrouds found on such oars to prevent erosion of the shaft where it sits in the rowlock. The oars were then bundled together and lashed to the thwarts on either side of the boat.
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