Form1 FEP based resin tray prototype

Forever… not really, but the surface of the FEP film does not degrade or fog like pdms so you end up replacing it when it gets damaged: dented, gouged, stretched out of shape etc. so I will say conservatively 50 - 100 prints but hundreds of prints are not unheard of using FEP film as a release layer. Also. the vat kit will come with either 2 or 4 replacement FEP/gasket sets (1 FEP, 2 gaskets per set), replacement FEP and gasket sets for this sized vat will run about $12.00 - $14.00 per set.

Nice! Are you willing to make ones for the Form 2? I would be very interested.

I do not believe the form 2 can be made to work with FEP, FEP is too “sticky” for the sliding action. However, the peel and wipe action of the form2 should actually makes the form 2 resin vats last much longer, In a form1 vat the pdms degrades mainly because the layer of oxygen on its surface becomes depleted if not exposed to the air and the pdms will slowly lose it’s non stick properties because it is submerged in resin while printing, when this happens microscopic bits of the surface begin to get torn away during printing (the fogging you see, think tape on sand), on a form2 one of the wipers purposes is to renew that oxygen layer by exposing the pdms surface to the air thus renewing the oxygen layer and maintaining the non stick properties of the pdms this makes the form2 vats last longer than form1 vats.

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I think it might actually be OK with the Form2. With open mode the wiper is disabled, and I’m assuming that a decent majority of people that are interested in you system would be using a 3rd party resin in open mode anyways.

Just something to think about, you might have some more potential customers.

I appreciate all of your detailed information, it is very helpful!

If Formlabs opened up the Form 2 for “hacking” like they did with the Form 1+, couldn’t the wiper and peel mechanism be disabled / modified and the Z pull-up with a FEP vat be the sole peel mechanism. Similar to how I gather the Slash will work… if it is ever released…

Seems like the best of both worlds. The printer could act exactly how it does in “closed” mode or change it with an equivalent of OpenFL and the API for open mode and completely change how the peel process works. Then the printer could be tuned for 3rd party resins as well. I guess well just have to wait and see…

@HTL, thank you for sharing the detailed resin experiments process and results.

Here is a photo of the vat. The FEP film is clamped between the top plate (vat wall plate) and the base plate using 2 gaskets. The acrylic support plate is inserted from the bottom of the vat and is held and tensioned with a snap in retainer. The vat is made of cast polyurethane and the support plate is made of cast acrylic (so it can be cleaned with alcohol without cracking or crazing).

Looking good.
With the polyurethane I assume your casting these from resin? If so did you add a uv blocker to it such as SunDevil or something along those lines to prevent degradation?

You have a guesstimate of when finals will be for sale along with costs including FEP replacements?

The dye i use with the polyurethane is specifically a uv blocker, btw you can buy any of my vats in any color as long as it’s light gray (dark gray on special order : ). The kit will contain the vat, the build plate assembly, 3 sets of FEP and gaskets (1 set mounted, 2 spare sets), 2 acrylic support inserts (1 mounted 1 spare), the snap in support retainer and misc minor hardware. The vat kit will sell for approx 140.00 usd. The vat kits I sell include spares of items (FEP/gaskets) that may wear out and parts that may be be damaged from handling (acrylic support plate), because most of the people who purchase my vats use them for work I try to supply vats kits that will not shut them down because of a damaged or worn out component. I am shooting for availability the first week of may over at flexvat.com.

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Light gray is fine, most the parts I cast here have been light gray too :slight_smile:
My current tank is almost expired so will snag one of yours when I’m due.

If you happen to have a FL cleer 02 resin settings please post.

I have a few updates on the FEP vat:

The first thing is that the vat availability will be pushed back into next week. During testing, which not only involves making exposure tests but also assembling and disassembling the vat, I found that the base plate was not holding up as well as I expected. Specifically the molded in threaded inserts were pulling up slightly from the tension put on them from clamping the plates together and the base plate was not staying as flat as I wanted. Those are not the kind of flaws I can put out in he wild so I re-designed the base plate (actually as two plates in a sandwich) in aluminum. I sent the base plate design out for waterjet cutting today and the parts should be in by the end of this week or the first thing next week.

Still so far so good with the exposure testing. I went back to testing Formlabs resins for a while and have come up with a pretty good OpenPF material file for Formlabs gray v2. I was having some print failures until I realized that the formlabs resin on FEP wanted a bit of a slower down tilt (I slowed both the p1 and p2 down tilt to .75mm/s from 1mm/s and 1.5mm/s respectively although only the p2 tilt as giving me trouble). Note: you can think of the p1 tilt as the tilt for the raft and supports and the p2 tilt as the tilt for printing the model.

If anyone wants to look at the material files and other information that would only serve to clutter up this thread you can find some information here:
http://projectsinterestsandetcetera.com/form1-fep-vat/ . I will be uploading some material files later on today

Also all of the information for obtaining Preform OpenPF, notepad++ (for editing material files) and Formlabs sample material file (clear v2) can be found here: http://forum.formlabs.com/t/form1-fep-based-resin-tray-prototype/12435/35 . I edited the post to add the links to the OpenPF installers.

Ring (http://www.thingiverse.com/thing:338040) printed with Formlabs Gray v2 with .1 mm layers (I will be testing .05 and .025 layer prints over the next couple of days):

I was considering retiring my F1+, but this looks like fun. How soon can I order a few vats and the build plate?

I’m really interested!!
Want to buy one and start use MS resins…but…I’m so neewbie in this world…it’s hard to setup the printer with the new configuration? I mean…do I have to change many things in preform and in the printer?
Will the pet vat come with clearly instructions?

What I understand…peel motor will be out right?? The FEP vat only works with z to low and up the building platform?

All of the items printed with the FEP vat used the form1+ tilt. I slowed the tilt speed for the above ring print, also, 4 rings were printed at the same time.

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The water jet cut base plates for the vat have come in and they look pretty good, It looks like the vats will be available at flexvat.com next week.


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Waiting more news!! It looks awesome dude!

Any news about FEP?
Can we buy it yet?

I just wanted to post an update on the fep vat. I am currently working on instruction sheets, videos, doing work on packaging etc. but I have also added an interesting feature to the vat. As you know the vat clamps the FEP film, gaskets and support plate between the top clamp plate (the vat wall) and the aluminum bottom plate assembly. A week or so ago I realized something that should have been obvious from the start, that is, if you could clamp FEP for use as the vat floor you could also clamp a sheet of acrylic with a coat of pdms and have a vat with very economical pdms release layer replacements for those who want to use pdms rather than or in addition to FEP. Instead of replacing an entire vat when the pdms layer wears out you just replace the pdms coated acrylic insert. I am still working out production details but It looks like the inserts can be made for about $15.00 each.

The photo below is of the acrylic insert, I have pulled the pdms coating off of the insert because the coating setup I made was a rtv silicone casting and guess what, rtv silicone inhibits the cure of pdms, so the top surface of the insert was perfect but the areas where the pdms touched the silicone form exuded uncured pdms goo over the surface of the insert. I have a replacement form made of urethane rubber curing as I write this post (48 hour cure time) that should solve the pdms cure inhibition problem. The slots in the acrylic help to seal the pdms to the acrylic. Without the slots the pdms would be prone to lifting off of the surface of the acrylic.

I believe the PDMS for the Form1/1+ need to have some thickness to them because they add a cushion to the printing process especially on the initial print (compression) layers. If that layer is too thin then the forces on the acrylic below may cause it to crack. Form1 tanks are notorious for cracking especially on the back left corner where the forces are greatest.
I believe your FEP tanks offer enough flex and don’t have the acrylic below to crack.

The thin pdms pads might be ideal for the z-vats that use glass bottoms and polycarbonate sides but not sure how you would be able to apply them.

The pdms layer on the insert will be 2mm to 3mm thick. To produce the insert the laser cut acrylic is placed in a “rubber” form that tightly fits the edges of the insert, The form also has “pins” that extend through the bolt holes in the acrylic plate. PDMS is mixed and poured into the form and after curing the insert is ready to be used without any other processing or needing any gaskets (the pdms itself acts as both the release layer and gasket). Also, the thickness of the pdms is not critical because of the adjust-ability of the build plate. The pdms inserts will be an optional part for the vat.

Henry, the vat you created seems to be well thought through and looks very promising.
I’d like to use the Form 1+ for rapid prototyping and am therefore interested in the level of achievable dimensional accuracy for objects of different sizes.
If you’ll find the time, could you please run a test print of following objects?

Epicyclic.zip.stl (675.0 KB)
(3 files zipped, parts of one stage of a planetary gearbox)
The outer diameter of the
annulus: ~80mm
planet : ~30mm
sun: ~9mm

It printed well in PA on an industrial SLS printer.
The gears work together although it’s quite a tight fit.

thank you