Centurion AVLB (slow build)

[Guest]

Ah, I understand now why there are two widths in the photos — I was wondering about that. Glad to read you didn’t have to make a complete treadway from bits of plastic strip, as I feared at first

Though to be honest, I would have looked for someone who owns a laser cutter for this: draw the pattern on a computer (which would be largely copy-and-paste-work) and just have the device cut all those little holes in a bit of plastic card of the right thickness.

[Jim R]

Hi Mike
Just had a proper look at your earlier photos on the big screen. Brilliant work. Very neat and I can imagine the time taken. Wonderful work on the treadway. The building of the master must have tested your patience although the actual casting is fairly straightforward. You look to have nice, bubble free castings.
Jim

[JR]

Ah, I understand now why there are two widths in the photos — I was wondering about that. Glad to read you didn’t have to make a complete treadway from bits of plastic strip, as I feared at first :smiling3:

Though to be honest, I would have looked for someone who owns a laser cutter for this: draw the pattern on a computer (which would be largely copy-and-paste-work) and just have the device cut all those little holes in a bit of plastic card of the right thickness.

Unfortunately he doesn't have any friends with such things:smiling3: I had one of those sketch things thought:upside:

[stillp]

Do laser cutters work on plasticard?
Pete

[Guest]

https://www.eurolaser.com/materials/polystyrene-ps

[Scratchbuilder]

Ah, I understand now why there are two widths in the photos — I was wondering about that. Glad to read you didn’t have to make a complete treadway from bits of plastic strip, as I feared at first :smiling3:

Though to be honest, I would have looked for someone who owns a laser cutter for this: draw the pattern on a computer (which would be largely copy-and-paste-work) and just have the device cut all those little holes in a bit of plastic card of the right thickness.

There are also studs that were added to all junctions (not visible in the pics). And you cannot use a laser cutter on plastic, it will melt it, plus why do it that way when the enjoyment is working out the problem youself and realising you have achieved something.

[Scratchbuilder]

https://www.eurolaser.com/materials/polystyrene-ps

That is polystyrene and not plastic sheet.

[Scratchbuilder]

Hi Mike
Just had a proper look at your earlier photos on the big screen. Brilliant work. Very neat and I can imagine the time taken. Wonderful work on the treadway. The building of the master must have tested your patience although the actual casting is fairly straightforward. You look to have nice, bubble free castings.
Jim

Jack Daniels helped a lot to ease the pain....:tongue-out3:

[Scratchbuilder]

Unfortunately he doesn't have any friends with such things:smiling3: I had one of those sketch things thought:upside:

And you still tried to use your crayons on it.... :smiling5:

Do laser cutters work on plasticard?
Pete

No, they work on polystrene which is like foam rather than card.

[Guest]

There are also studs that were added to all junctions (not visible in the pics).

That makes it a whole different game, yes. By casting it in sections you avoid adding a lot of pieces that you would have to laboriously add when cutting the plate as a whole.

you cannot use a laser cutter on plastic, it will melt it

The site I linked to (mainly because it was the first one I found) sells laser cutters suitable for plastic sheet that avoid this problem. Here’s an example from that site:



OK, these are industrial machines, but with a bit of luck, there are hobbyist-scale ones to be found with similar capabilities.

That is polystyrene and not plastic sheet.

I think you’re confusing polystyrene in general with expanded polystyrene foam. Nearly all model kits are made of hard polystyrene, as is the kind of (usually white) plastic sheet/card most commonly used for scratchbuilding.

plus why do it that way when the enjoyment is working out the problem youself and realising you have achieved something.

I also get that feeling after drawing something intricate But that’s the beauty of modelling and scratchbuilding, IMHO: you can build it the way you think works best, and I can get much the same result via another technique. Does that make either better than the other?

[JR]

That makes it a whole different game, yes. By casting it in sections you avoid adding a lot of pieces that you would have to laboriously add when cutting the plate as a whole.


The site I linked to (mainly because it was the first one I found) sells laser cutters suitable for plastic sheet that avoid this problem. Here’s an example from that site:



OK, these are industrial machines, but with a bit of luck, there are hobbyist-scale ones to be found with similar capabilities.


I think you’re confusing polystyrene in general with expanded polystyrene foam. Nearly all model kits are made of hard polystyrene, as is the kind of (usually white) plastic sheet/card most commonly used for scratchbuilding.


I also get that feeling after drawing something intricate :smiling3: But that’s the beauty of modelling and scratchbuilding, IMHO: you can build it the way you think works best, and I can get much the same result via another technique. Does that make either better than the other?

My thoughts on the last part of your post. Many times we have made items for builds, then time passes and you see a ready made item you have struggled to make . Then you think what should I do buy it or still make it . I think two things, how much does it cost against making one, and have I the time. This applies to me mainly when making buildings and trees .

[Scratchbuilder]

Update.
So debate over tea drained and back to work..... Thanks Jakko for the information.
The rear support for the bridge is next on the agenda. First was the uprights and then the crossmember that will support the bridge during transport as seen in the earlier pics. Attached to this are the support legs used during servicing of the vehicle if the bridge is loaded. Also added was the new lifting eye just ahead of the support upright on both sides.

[adt70hk]

As always Mike, such great scratchery in such a small space.

[Scratchbuilder]

Next on the order of build are the two clamps at the rear of the cross members. I started with the locking wheel handles - these were made from copper wire wound around a suitable rod and then the resulting 'spring' was cut to to give me four rings (two replacements) into these was added the cross and the centre disc. Once complete they were given a blend of thin putty to try to give the impression of a cast item. The Clamp blocks are made from plastic card and are shown almost complete. I should add that the 'cross' is centered in the ring and the studs on the outside were added after.
More later....

[Scratchbuilder]

As always Mike, such great scratchery in such a small space.

Cheers Andrew.