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moai:vat

Vat

The Moai vat is made of high-grade acrylic that can endure ethanol and IPA cleaning. We recommend ethanol over IPA because it is less corrosive. The interior of Moai vat is lined with PDMS layer. This PDMS layer should last 15-20 prints with Moai resin if recommended exposure settings are used. Users can recoat their vat with the instructions below from David Wang Honey (Fezzik) on the Peopoly forum. https://forum.peopoly.net/t/how-to-restore-your-vat/195.

How to Restore Your Vat

SOOOOO, you ruined your PDMS layer in your VAT??? Buy new one? Sure (I do suggest a vat for each resin type you use) The Resin tank silicone layer PDMS (polydimethylsiloxane) wears out over time. It can also pull away, tear, or cloud causing failed prints. Lets save the VAT with making a new PDMS layer. Lets show you how to do this.

Out with the old

First you need to remove the old PDMS layer. You can get the spatula and pry up on the vat from a corner.
BE CAREFUL to not scracth the acrylic if you can.

Here it is out.

Cleaning

If any of the resin gets on the acrylic be sure to use ethanol over IPA because it is less corrosive to clean it up. Use a LINT free towel. I use bounty towels and it works well. Coffee filters work as well. (Denatured alcohol with 90%+ ethanol is probably the most inexpensive option in the US)

Polishing

So now lets address what happens if you do scratch the acrylic. I had my PDMS layer tear and some resin cured on the bottom acrylic. Removing it scratched it pretty bad.

You can see it in the middle to the left where the blue is distorted.

So what you are going to need is the Novus acrylic polish and cleaner. I got mine from amazon: Amazon.com: NOVUS 7100 Plastic Polish Kit - 8 oz.: Automotive

Polishing Kit to clean and restore plastics. Kit contains a bottle each of NOVUS No. 1 (part no. PC-10), NOVUS No. 2 (part no. PC-20), NOVUS No. 3 (part no. PC-30) Polish, an informational brochure an …

$21.00

I used a sponge pad I got from a 3M headlight restoration I already had. You COULD do it by hand but it will take you forever and this works so well.

Amazon.com: 3M 39008 Headlight Lens Restoration System: Automotive

Plastic lenses can yellow with age, reducing headlight brightness, and new lenses can be expensive. The 3M Headlight Lens Restoration System lets you shine and restore plastic lenses, including headli …

$15.95

If you have a bad scratch start with #3 until it is almost all gone, then go to #2, for the fine polish and then #1 is a wipe clean. Do not use a cloth for the cleaning. Use a bounty towel, a lens cleaner sheet, or coffee filer.

Re-Coating

Now that the acrylic is cleaned and clear of scratches, you will need to get some sylgard 184. This is the same stuff they put on solar panels. I was about to buy the actual sylgard 184 on amazon (its also backordered a lot) from dow corning: amazon.com5 Sylgard Solar Cell Encapsulation for Making Solar Panels: Amazon.com: Industrial & Scientific

Sylgard 184 Silicone Elastomer is suitable for: LED Lighting encapsulation, Power supplies, Connectors Sensors, Industrial controls, Transformers, Amplifiers, High voltage resistor packs, Relays, Adhe …

$79.95

BUT Paul Yanzick found some on ebay for much cheaper; about half the price. The sylgard from dow corning was backordered for a few weeks so i decided to try the same stuff Paul came upon. You can find it on ebay or amazon from the same seller. Fast shipping! Amazon.com : Cell Guard Solar Cell Encapsulation for Making Solar Panels Comare to Sylgard : Childrens Pinatas : Garden & Outdoor

This is 1.1lb kit of Cell Guard solar cells engapsulation kit. This is the same as Sylgard 184. It has the same work time, cure time, lifetime, clarity as Sylgard. This is the standard 2-3 hour work t …

http://www.ebay.com/itm/Cell-Guard-PDMS-Material-Compare-to-Sylgard-184/172542720937?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l26496

https://www.imakr.com/en/accessories/275-b9-pdms-vat-re-coating-kit.html?search_query=pdms&results=5

https://www.3dogg.com/a-48146313/fep-film-pdms/pdms-coating-250gr/

A side note: One bottle of silicone and 1 bottle of activator we figured can do 5 vats at once, or probably 4 if done separately. You will have some excess that you will lose each time.

I bought bulk because I am testing a lot of resins out and was tearing the PDMS layers.

Measureing

You will need a 10:1 ratio of silicone to activator

FOR ONE VAT: 80mL of Silicone and 8mL of activator

80mL of Silicone

8mL of activator

Mix the two together in a disposable cup. Mix it well. It will develop a lot of bubbles. This is OK.

Take your empty and clean (of dust too) Vat and put it on a scale. 0 (zero) the scale with the vat on the scale. Pour in about 65-70 grams into the vat.

Level the Vat

You will now need to level it and be sure to check it both directions.

Cover the vat up to keep dust off of it. I printed off a members vat cover and it works well as a dust cover. I let the vat sit for 2 days to fully cure. Test this by gently poking a corner and see how it feels. It should not be sticking and bounce back if a finger nail is gently pushed into it.

WHAT ABOUT ALL THOSE AIR BUBBLES!?!?!?!?!? Well this material is designed to self clear the bubbles out.

20 mins after pour

45 mins after pour

I have restored 5 vats with this method and have already been printing on these. I feel these may be a little stronger, but still have to be careful with it.


Here is a vat recoating guide from ApplyLabWork

https://www.applylabwork.com/content/printingtips/vat_recoating_instruction.pdf

moai/vat.txt · Last modified: 2018/04/16 17:07 by lyndondr