VAT design

Various topics related to Vat design, construction and coatings.
hpuzwf
Posts: 1
Joined: Wed Jun 01, 2016 4:27 am

VAT design

Postby hpuzwf » Wed Jun 01, 2016 9:19 pm

Do you have a good solution of VAT?I require a VAT,do you have one ?thank you

lasersafe1
Posts: 14
Joined: Sat May 21, 2016 1:20 pm

Re: VAT design

Postby lasersafe1 » Sun Jun 05, 2016 11:07 am

You seem to be at the same point as I am. I've been researching the various existing vats and methods to handle printing. Many folks build machines that tilt their vats to help with release, and some machines don't use tilt at all and let the vat flex on its own. There is a Youtube video by James Kao where he has been doing recent comparisons (April 2016) of vat technology and I think he has abandoned all models from previous years in favor of his new simplistic "tape vat". Ok, it is not "his" design, I guess it came from the daylight polymer lcd printer design, but for the purpose of this discussion I'm going to call it his design.

https://www.youtube.com/watch?v=KVp9-xW7kzk

This is another tutorial: http://media.wix.com/ugd/bee1f3_d8409aa2f50242f48777aeaf8960fb84.pdf

He prints large items. Very large! So of all people, he would be one who would seem to need the tilting peel, but he doesn't. The FEP in his vat is flexible enough to lift within his frame even when his frame is held solid. The FEP is not "drum" tight as you see in the mUVe flex vat.

If you check his videos, he has another that explains in detail how to build the tape vat.

His design is very nice, but I don't like the idea of having to use a fused filament printer to make a frame. I was planning on taking a trip to a local hardware store and looking around for some common item that can be used as a frame. Perhaps some kind of ABS toolbox, or perhaps a small bathroom garbage can. I am also thinking of Michaels arts and craft store and looking for some kind of square acrylic dish or picture frame. Anything that looks to be an appropriate size where you could cut out the bottom and stretch the FEP across. I have a CO2 laser cutter and a CNC mill, so putting a good square in the bottom of an acrylic dish will not be a problem. With the laser cutter I could also do a hybrid of James' design where I can put pins on the square frame and laser cut holes in the FEP so it can just be stretched over and catch on the pins.

Realize also that if you are cutting a square out of the bottom of a dish to make an area for the FEP to stretch across, you could reuse this square to be the firm backing that is required. You would simply cut the square about 1/4" smaller in all dimensions and you would bolt your vat back down the the print bed over this square. This gives you the solid base and also stretches the FEP a little more in the area you need stretched.

If I find the right dish for a simple tape vat, I'll be sure to post the part number and where I purchase.

I want to build my machine using a single stepper on the Z axis and no motorized tilting. This will let me use the Raspberry pi with NanoDLP software, but avoid the arduino and Ramps board that so many people seem to be having difficulty with failing communications.