FDM PLA 3D printing - with a model making inclination

[JR]

An early Holt 76 Tractor ?

[Dave Ward]

It's a Holt 75 - I'm printing the canopy at the moment - I did consider printing the Holt 120 - but that's a bit bigger & printing time was getting close to 30 hrs! I have printed out a BL6" Howitzer for it to tow. The Holt is blown up from 1/100 to 1/35 - is looking good - the only part that really needs replacing is the steering wheel!
The only 1/35 injection model of the Holt 75 is the 2018 Roden version - which has poor reviews & goes for £60+ This model will have taken about 1/3 of a filament spool, so the material cost will be <£5 - I'll be adding pictures of the cleaned up bits tomorrow
Dave

[JR]

It's a Holt 75 - I'm printing the canopy at the moment - I did consider printing the Holt 120 - but that's a bit bigger & printing time was getting close to 30 hrs! I have printed out a BL6" Howitzer for it to tow. The Holt is blown up from 1/100 to 1/35 - is looking good - the only part that really needs replacing is the steering wheel!
The only 1/35 injection model of the Holt 75 is the 2018 Roden version - which has poor reviews & goes for £60+ This model will have taken about 1/3 of a filament spool, so the material cost will be <£5 - I'll be adding pictures of the cleaned up bits tomorrow
Dave

I remember Steve Jones attempting to build one , said it was a terrible kit from Roden.
Keep af it Dave.

[Gary MacKenzie]

The Holt 75 model gasoline-powered Caterpillar tractor. Later models were produced without the front "tiller wheel"



EDIT : Apols , website is acting up , not showing any updates since your original post , then suddenly all the answers appeared,

[Dave Ward]

Interesting fact - 442 of the Holt 75 were built in Britain by Ruston & Hornsby. The slightly larger 120 had a bigger engine & 4 individual exhaust pipes, but otherwise looks the same

Dave

[Dave Ward]

Bits all printed - the canopy supports ( bottom right ) need a bit of fettling

Quite pleased with this, so far - and this is for towing

BL6" Howitzer - Both have had failures on the fine handwheels, which I'm trying to print out separately
Dave

[Dave Ward]

I'd ordered some 0.3mm & 0.2mm dia nozzles, to try to improve the detail printing. They arrived - and I've been attempting to print with them - almost like starting 3D printing from scratch! One major difference is the print time - what took about 2 hours with a 0.4mm dia nozzle takes over 5 hours with a 0.3mm one. & even longer with a 0.2mm. I haven't had one succesful print - one failed at 6 hours our of 8. I've tried all the normal tweaks, but that has introduced new errors, including stringing, & layer separation.
I've given up for the time being & gone back to 0.4mm, I just can't be bothered with all the hassle!
Dave

[Dave Ward]

A snowy morning in Gloucestershire! - not expected................
I've been very much under the weather since the turn of the year, and not managed any benchtime, but I've been hitting the 3D printer.
I found a drydock model, and after a lot of scaling trials managed to print it out at around 1/350 - it is in 9 pieces, for ease of printing................. but it still took around 50 hours in total

I found that my spare filament spool was in this bright yellow!, with a few failures, this has taken the majority of one spool!
This shows the intended use...................

The 1/350 hull of the Trumpeter HMCS Huron. just fits nicely, anyone would think it'd been sized to fit I do have a few full hull ships that could work, as well - 2 Mirage 1/350 Flower class corvettes.
Now I've printed this, I could shrink this to 1/700, but looking in the stash I've only two full hull ships that would fit - HMS Eskimo & a Liberty Ship ( tight squeeze ).
This is a Graving Dock, used for work below the waterline, such as repairing plates, or simply scraping & repainting - so there aren't any heavy cranes etc that may be found in a repair dock.
Dave

[Dave Ward]

Instead of benchtime, I've been concentrating on my 3D printing. I've been trying various different settings to improve prints. I think I've been turning out some good models - tanks in 1/72 scale - even at this scale models are taking about 5 hours to print, - at 1/35 they would take at least 3 times as long.
I've been concentrating on British tanks up to 1938/9
Done so far: Mark V Male, Mark IX, Medium Mark A Whippet, Mediuum Mark C Hornet, Mark XIII International, Birch Gun, Cruiser Mk II A10, Cruiser Mk III A13, Light Tank Mk VI, Matilda I A11
Still to do: Medium Mk. II, Medium Mk. III, Gun Carrier Mk I
Having difficulty in finding a decent model of the Vickers A1E1 Independent & some of the minor light tanks, but still looking.................
Some have turned out very well - I've been printing models in one piece if possible. normally recommended for resin printing, but with a little care FDM works ( in 1/72 at least ). I'd put up some pictures - but my camera battery is flat ( not been used for a while! ), so that'll be the priority first thing tomorrow
Dave

[Dave Ward]

This is the results of a week or so of daytime printing......................

All 1/72................... Using my favourite Geeetech PLA filament - most are printed in one piece, apart from those with rotating turrets, there are some quibbles - the unditching beams on the Mark V ( too small ), and the Mark IX ( too large ). All will benefit from a careful clean up and a good primer.
These are scaled up & down as needed - one that is missing is the Gun Carrier Mk I - I printed it overnight - it was fine, but it looked too small! I'd scaled it up from 1/100, and either the original scale was wrong, or I dyslexed the scaling factor, so it's reprinting.
Dave

[boatman]

HI Dave really like your tanks they look very good very well done
happy modelin
chrisb

[Dave Ward]

Gun Carrier Mark I - printed in one piece, with organic supports still attached

A few minutes work with side cutters..........................

A year ago, I didn't think it was possible to print these in one piece, but after a lot of printing & tweaking, I find it can be done.
In this sequence of 1/72 models, I've used about 1/2 spool of filament - ( £13.50 a spool ) I've had no failures ( apart from printing at the wrong size ). I carefully levelled the bed manually at the start, and haven't had to adjust it.
Next up will be the Vickers Medium Mk.I, Mk.II & Mk.III - still looking for a decent Independent
Dave

[boatman]

WELL Dave i find this 3D printing beyond me but its comin out very good is it heavy at all ?
chrisb

[Dave Ward]

heavy at all ?

PLA is actually heavier than water, but the models have a surface layer of 2-3 mm & the internal fill is 8% ( think of it as a internal stiffeners ), so they are quite light - but not that strong!

Dave

[Dave Ward]

I struck out on finding a good free model of the Vickers Independent tank, so I had to actually buy one.........all of $10
This is not my model, it's the sellers...........

In 1/56, so scaling down should be easy.
There was only one Independent built, but it's design influenced a few other tanks, like the Soviet T-100, T-28, T-35 & the Gernan Neubaufahrzeug, so it has it's place in tank history!
One model I can't find, even to purchase is the Christie 1931 - or T1 Combat Car - the suspension design was taken up by the Soviets in the BT series & T-34, and the British Cruiser tanks............so another important milestone
Dave