Mick's Vietnam Book (Outstanding orders fulfilled. page 18)

[carlos marighela]

Carlos,

Your T55s look great  - which colour did you use?

Thank-you for the links to the decals.
I got quite excited and added some to the shopping cart.
Then I saw the cost including shipping to Switzerland ouch.

I will consider carefully what I actually need.

Standard Tamiya rattle can  TS-28 Olive Drab 2. Funnily enough, I just opened up the box to start on another one (going to open up the loader's hatch this time) and saw that Tamiya suggest TS-28. There's serendipity for you.

The dirtying up is down to Mig and Vallejo pigments.  I used to faff about doing Soviet Green but eventually came to the conclusion  that most olive greens are much of a muchness and weathering makes up for/ hides most of the differences.

Surprised that postage would be expensive from France to Switzerland. You are next door to each other after all.

[Ultravanillasmurf]

No idea what the postage is but, I-94 have some Vietnamese stars for aircraft in pack MI-106.

https://www.minibits.net/i-94-decals/miscellaneous/

I have them somewhere, I will see if I can dig them out.

The odd number forms might be interesting to render.

Apologies for the delay.

MI-106 next to an Empress T55.

More photographs of the decals here: https://ultravanillasmurf.blogspot.com/2021/04/north-vietnamese-decals-i-94.html

[Mick_in_Switzerland]

Ultravanillasmurf - Thank-you

I think they will work very well

[Mick_in_Switzerland]

I have decided to join the Build Something Competition.

This year the theme will be difficult terrain. I have decided to do a tile for a battle on a steep wooded hillside. There were several battles in the Vietnam war that took place on steep wooded hillsides.
I made a wooden easel which holds XPS tiles. I have then started to sculpt the XPS foam. I think this has potential to make an interesting competition piece.


You can follow the project here.
https://leadadventureforum.com/index.php?topic=130670.0

[Ash]

Now that's an interesting idea.

[Ultravanillasmurf]

That makes sense now

"you know that moment when the ophthalmologist shows you a picture, and suddenly it comes into focus and you realise you are going have to spend a lot of money on glasses..."

On the larger screen you can see the trenches (on the other machine they looked like raised blobs).

[tomrommel1]

That is a nice concept!!!

[Mick_in_Switzerland]

At the end of March 2021, I backed a Kickstarter "3D Printable US Vehicles of the Vietnam War, for Wargames by Brad Sanders".
The Kickstarter funded and the files were available to download on 14th April.

I enquired among my friends and work colleagues but could not find anybody willing to print them for me.

On 19th April after some internet research, I ordered an Anycubic Photon Mono SLA resin printer This arrived on Friday and I printed the test cube.

On Saturday, I managed to print and assemble a 1/50 scale M113 ACAV with all of the tracks, guns and gunshields. Printing took about 4.5 hours for the body and 1 hour for the tracks and guns. Assembly was only 6 pieces glued together with cyanoacrylate superglue. The quality of the model is excellent. I broke a mudguard and a M60 mounting post during the removal of the supports – mostly because I was clumsy.
At this point, I was excited and dreamt of huge battles, fielding a dozen vehicles.



The next model I tried was the M551 Sheridan tank. I printed the tracks without incident but since then all my prints have failed. I have stripped it down, washed everything and filtered the resin. All with no avail.

I have concluded that I have damaged the FEP film, and the resin is now contaminated. I have ordered more resin and a new FEP film. Once they arrive, I replace the FEP film, and zero the Z again and try again with the fresh resin.  I can see that this is not as easy as I first thought.

[tomrommel1]

Nice print. When you get the new FEP film be aware that there is an ultra thin layer of plastic on the FEP, you have to remove this before use!!! Did that wrong once and it didn't work!!!

[Mick_in_Switzerland]

Dear Tom - thank you for the advice.
There is a lot to learn about 3D printing.

[tomrommel1]

Indeed there is, but the learning curve is quite steep

[Mick_in_Switzerland]

I ordered some more resin and a new FEP and then restarted my 3D SLA printing experiments.

Here is an M551 Sheridan from the recent Kickstarter.



And here are two water buffalo and two Cambodian temple lions found on the internet.

[Mick_in_Switzerland]

3D Resin Printing Thoughts
I have now printed five vehicles and started to draw some conclusions about 3D resin printing. Here are my thoughts.

Printing Process
You will need
•   Printer – I bought an Anycubic Photon, which is recommended for beginners. Anycubic Photon X is a larger version of the same machine.
•   Resin – 1 litre of resin will make four 28mm M113 AFVs.
•   Washing Bath - You can make a simple bath with a 3 litre Tupperware with a sealed lid and fill it with a litre or two of Isopropyl alcohol. A Wash & Cure machine is not needed at the beginning. You should wear gloves to protect your skin from resin and alcohol.

Before you start, you can protect the LCD with a thin sheet of cellophane and stick it down all round with masking tape. This protects the expensive LCD parts if you have a resin spill.
Make sure that the printer is on a level surface. Follow the instructions and level the printing plate to match the LCD. Also set the Z axis at the same time. Check that the FEP film on the bottom of the resin vat is in good condition. Replace the FEP if there is damage as this could leak.

Prepare the file with the slicer software. You can print several parts at a time as long as they do not overlap. Make sure that the Exposure is in the correct time to suit your resin (e.g. Bottom Exposure 30-60 seconds. Normal exposure 4-5 seconds). Save the sliced file to a USB stick and transfer this to the printer. The software will tell you the expected print time which could be an hour for small thin parts up to six or more hours for a 28mm tank body. The software will also calculate the volume of resin required.

Set the print running. Check after an hour and every two hours after that to ensure that there is enough resin and the print is working. The pause button is useful as this raises the printing plate so that you can see the model clearly.

Wearing gloves, remove the model and place it in the alcohol bath. Shake gently so that the printed parts are thoroughly clean. If necessary brush with an old toothbrush. Some recommend to wash in old alcohol to get the worst off and then a second wash in new alcohol to get the part thoroughly clean. You can also wash in warm water. Allow the parts to dry.
Remove the supports using craft scissors or sprue cutting pliers. Do not be tempted to just rip them away with your bare hands as you will break thin section parts such as mudguards and gun barrels.

In summer, you can leave the model in the sunshine for an hour to ensure it is fully cured. In winter, it is a good idea to have a UV lamp.
If you have a failed print, you need to clean the vat and remove all the blobs of hardened resin or these will mess up future prints. Empty the resin vat into an old bottle through a filter funnel. Do not pour old resin into a bottle of fresh resin as you will contaminate it. Wipe down the printing plate and the vat sides. Carefully clean the FEP. Clean away all blobs of hard or rubbery resin.  Replace the FEP if there is damage as this could leak. Refill with the old resin that has been filtered. Top up with fresh resin.

Printing and Assembly
Most vehicles consist of six parts - hull, two tracks, turret, cupola, and .50 Cal machine gun. It takes about 6 hours for the hull and then 2 hours for a combined print with the tracks, MG and cupola. If there is a large turret, this is another three hours. Once washed and cured, the parts need some sanding on the underside to remove the stumps from the supports. There is no need to clean up the upper surfaces.

Assembly is very quick. The tracks glue on with cyanoacrylate superglue. Turrets and cupolas can be fixed with magnets allowing them to be turned. This also means that you can exchange cupolas between buttoned up or crew visible. A big advantage is that if you damage a part, you can print another one.

I have painted them with Vallejo Spray US Olive Drab and then painted the tracks etc with Vallejo Model Colour, just as you would do with any other model tank.

Costs.
The printer cost about CHF 300 (£236), including shipping and customs duty. I damaged the FEP and had to replace it. This cost CHF 25 including postage. Then I bought a large Tupperware and some gloves. The total machinery cost was CHF 350, which is £280. Since then I have ordered US$ 75 worth of upgrade parts from Soval.

I bought the STL files from a Kickstarter. This package cost US$80 (£58) and contains the M113 family of vehicles (M113A1, M113 ACAV, M106 Mortar Carrier, M577 Command, M132 Flamethrower, VADS), M48A3 Patton, M67A1 Zippo and M551 Sheridan Tank. Each vehicle is supplied with and without stowage and with a variety of cupola and turret variations. There are more nine vehicles and easily 30 or more variants. Each file is supplied in 1/150, 1/72 and 1/56 scales. If I print 10 vehicles the STL license cost is £5.80 per vehicle.

The resin is about Euro 40 per litre (£35) including shipping. Isopropyl alcohol costs CHF 6.70 per litre. I bought two litres and had CHF 10 postage. The alcohol gets quite dirty and lumpy quickly. It can be cleaned by putting it in a bottle on a windowsill. The UV from sunlight will harden the resin and it will sink as a sediment. Then the cleaned alcohol can be poured off and reused. Resin & consumables work out at about CHF 11 (£9) for a 1/50 scale M113 and CHF19 (£15) for a 1/50 scale Sheridan tank.

Break Even Point
I tried to work out the break even and it is roughly 50 vehicles compared to Tamiya or Rubicon plastic kits or 20 vehicles compared to good resin kits. However, as the current eBay price for a Corgi 1/50 diecast M4A3 is at least £60 plus P&P, then 3D prints are cheap by comparison.

[tomrommel1]

Nice report about the costs of resin printing. I would come up with very similar numbers , being based in Germany.
I got myself a washing and curing machine from Anycubic and it works a treat. Less spillage and dirt to clean up afterwards. Recomended.

[carlos marighela]

Interesting, particularly the cost/benefit break even.