Form1 FEP based resin tray prototype


#1

The link below points to some photos of a FEP based resin tray for the Form 1/1+ that I may be offering at flexvat.com provided further testing of the vat pans out. The photos are of a working prototype and a test part, the part is approximately 24mm x 65mm and was printed using standard settings for grey resin.

http://projectsinterestsandetcetera.com/form1-fep-vat/

HTL


projectsinterestsandetcetera.com


Custom resin tray with replaceable FEP film
OpenFL: an API for the Form 1 / 1+
#2

Now that is FANTASTIC! I was hoping someone was going to start working on this. I was planning on taking a vat that I get (hopefully) my Slash and cannibalize one to test this out with. Seems I wont have to.


#3

Considering that there is a possibility that original tanks may become scarce in the future this would be most welcome.


#4

Cool, does that have a smaller print area with the vat?
Also do you have a complete kit for the Form1+? Costs?


#5

The vat does have a smaller print area, about 115mm x 115mm. There is just no way to get away with a larger print area as the vat needs to have replaceable gaskets and FEP FILM. The vat also requires its own build plate (the form1 build plate is too large). I have not determined a price for the vat yet but I do plan to price it reasonably.

When I first posted the photos of the vat I did it sort of spur of the moment and did not include much information so I will add some now.

I sell custom designed FEP based vats and FEP film at flexvat.com and I have a technical blog at projectsinterestsandetcetera.com (which I have not updated as much as I would like, flexvat.com seems to have eaten much of my spare time). Since the time I opened flexvat.com I have received emails asking if I was working on a vat for the form1 (in addition to other dlp/sla based printers). I finally found some time to give to working on a vat for the Form1 and pretty quickly realized that, because of the architecture of the printer and its proprietary software, I would need to obtain a Form1 to create a vat, there was just no way to create a vat without one. So to make a long story short, I was able to obtain a form1+ for a reasonable price that was in very good condition that I could use for measurements and testing. The photos linked to above are the result of early form1+ vat design work.

Info And Technical details:

I am currently doing print testing and things are looking pretty good, no problems yet. The Form1+ tilt mechanism seems to be perfect for a vat that has the FEP film “supported” by a transparent acrylic plate. The vat is not a “drumhead” ( http://projectsinterestsandetcetera.com/diagram-flexvat/ ) but has the FEP film lightly tensioned on top of a transparent acrylic plate (I will make a diagram when I have time). There is also an aluminum faced build plate that has to be used with the vat, the build plate has height and level adjustments.

FEP does not fog, making 100 prints or more using the same FEP release layer is not unusual. Replacing the FEP release layer on a FEP vat is a matter of unscrewing several bolts then replacing two gaskets and a sheet of FEP film, this is a 10 or 15 minute process, it is also pretty inexpensive. The consumables for a FEP vat are laser cut foam gaskets and FEP film (the gaskets and FEP can even be hand cut if need be).

I have been using Preform OpenPF for testing but if you are using Formlabs resins it does not matter if you use Preform or Preform OpenPF you would just use the profile for the Formlabs resin. Since the vat release layer is FEP film you can use other resins without worrying about damaging the release layer. At some point I am going to try to create OpenPF “material” ini files" for a few 3rd party resins that can be used with OpenPF but this will take some time.

The Form1 vat will be made of solid cast polyurethane, cast polyurethane vats are not fragile and are highly resistant to chemicals. Also, a vat made of polyurethane should last the life of a printer. The acrylic FEP support window is made of “cast” acrylic, laser cut cast acrylic does not have the locked in stresses that cause “extruded” acrylic to craze and crack when cleaned with solvents like alcohol. The vat can be cleaned with alcohol and/or dishwashing liquid.

If testing pans out I should have vats available over at flexvat.com in 4 to 6 weeks, I will update this information when I can.

HTL


#6

Sounds Awesome!, can’t wait till you update us.


#7

Some testing updates.

I started testing the FEP vat using Formlabs Grey resin and the results were ok but not stellar however when I tried Makerjuice SF I got an excellent print right off the bat using the unmodified settings for Formlabs clear resin. The photos below are of the FIRST test print with the prototype vat using Makerjuice SF. I am actually happy about this result not only because it shows that third party resins will work well with the FEP vat on a Form1+ but also because I find the Formlabs resin to be about the thickest stickiest resin I have ever used which made cleaning the prints and vat a bit of a chore . I’m used draining vats after I use them then cleaning the vat using a spray bottle of 90+ percent isopropyl alcohol followed by a water rinse (you can basically clean a flexvat.com vat like a dish, alcohols and dishwashing liquids etc. are no problem).

The print was made with Makerjuice SF resin using the unmodified settings for Formlabs clear FLGPCL02 with a 0.1 mm layer thickness. The print is 100 mm tall and took about 2.5 hour to print.


#8

Print made with Makerjuice SF resin using the unmodified settings for Formlabs clear FLGPCL02, 0.05mm layer thickness. The print is 75mm in diameter and took about 4.5 hour to print.

The stl is from this website: http://www.georgehart.com/rp/rp.html
of this model: http://www.georgehart.com/rp/chiral-2-layer-sphere.stl

Same as above but 35mm dia. with 0.025mm layers. Made with Makerjuice SF resin using the unmodified settings for Formlabs black FLGPBK02. took about 3hrs 55min to print. I find that 0.025mm layer prints are a bit thin when using the clear FLGPCL02 settings and a bit thick with black FLGPBK02 settings so I wiil probably try my hand at creating an OpenFL ini material file for that layer thickness.


#9

These results are very promising.

Can you print some parts to show dimensional accuracy. Can you print solid models successfully, say a 4"x4"x4" cube. Something a Form 1 series printer has never been able to do?


#10

I am assuming you are not asking for a print that is a 4" solid block of material, a print like that would use an entire liter of resin and would fail for all kinds of reasons. If you are asking me to print a cube shaped hollow or geometric model of some sort I have no problem with that. If you have a model to suggest please post a link to it and I may give it a shot. As a matter of fact I would like suggestions for a few models to print, some every day bread and butter type work and some that are a challenge to print would be good. I can’t say that I would be able to print everything but I would try to print a good cross section of any items suggested. I will be doing more testing later in the week, I will also be testing Makerjuice WaxCast later in the week or next weekend to see how well it prints.


#11

Yeah, I was asking about a solid block. Formlabs printed one with the Form 2. Many here (many years ago) had asked Formlabs if the Form 1 / 1+ could print it. We never really got an answer (from what I remember) and I know that it can’t. I was wondering with the FEP film if it would be possible. It is a waste of resin IMO but it would be a really good test if it could. It isn’t something I would ever print but there are some here that have tried to print solid models and they usually fail.

For test models, anything that can be measured to show accuracy. I would stick with something simple. Cubes with holes in it. Easy to measure the outside and inside accurately. I could always draw something simple if you want. Just message me and we can discuss.


#12

I would not be inclined to spend between 60.00 (makerjuice) and 150.00 (formlabs) on resin to make a single test print that has no practical use. Some smaller items are printed solid but any object of any size would be printed hollow or hollow with internal supports. There are plenty of cube shaped models available and I may print one if I find the time but I am more interested in making test prints that reflect the type of prints that are commonly made using the form1, for example, prototypes, jewelry, dental etc.


#13

That does look really promising. You are right about FL resins being thick and difficult to clean. The smaller build area should be no drawback since the cost of swapping out from the PDMS is such a huge gain.

I would like to see tiny details, some small text that you would see on a ring or coin etc.

Hollar when they are in the store!


#14

Printing a full cube will prove two things:

  1. if the peeling mechanism can peel the maximum possible cross section
  2. if the Z-axis can hold the full weight.

Both can be tested without wasting resin:

  1. Just print a 5mmYX box(50 layers should prove it’s capability).
  2. Apply a weight on the Z-axis while printing the above part.

#15

I wanted to find the most difficult model possible to try to print and I found this: http://www.thingiverse.com/thing:1972239

The print is 35mm x 40mm on a 40mm x 40mm base. The model was printed with Makerjuice SF resin using the unmodified settings for Formlabs black FLGPBK02 and 0.025 layer thickness. Note that overhangs printed fine without supports and the ramp like structures in the middle of the print are paper thin and also unsupported (so thin that when I blew on the part to try to remove some water from the rinse two bent). The cone shaped basket like structure on the corner of the model also sits on a unsupported ledge, the corner of that ledge appears to show some signs of failure. The “Raised Text” text is about 1mm tall and “Relief Text” is about 1.5mm tall.

I have found that the standard formlabs materials profiles lowers the layer “exposure” at a height of about 5mm or so, this can clearly be seen if you look at the part edge on. Evidently this is done to harden supports (which the form1+ seems to want you to use). I have found that that printing with the FEP based vat and Makerjuice resin can lower or eliminate the need for supports some cases, I have not used supports so far in my testing because I want to find where and how prints fail when using the vat.


#16

This is done to improve adhesion to the build platform.

If you want to test the most difficult situations, print something very tall with supports and a decent cross section with thin parts in between and check dimensional accuracy and bending of the supports and the part. Printing these test files(also the formtest file released by formlabs) is relatively easy.


#17

It would seem to me that the eiffel tower print above fits the criteria for a tall structure with fine details and a decent cross section (although support were not needed because supports were not needed with this combination of vat and resin). Also, on the form 1+ only the first layer or two are used for bed adhesion (10 laser passes for bed adhesion layers, 2 passes for early layers (supports) and 1 pass for normal layers). As I have said previously I would be happy to make test prints that reflect the type of prints that are commonly made using the form1, for example, prototypes, jewelry, dental etc. If there are people following this thread who have models that they actually print on a production basis I would be happy to make a test print of your model.


#18

Very nice prints. Are they dimensionally accurate?

The first ~5mm of over exposure is for bed adhesion and support strength. This can be modified with custom profiles. With using the custom ini file, we can modify the 5mm double exposure as well as get more accurate prints with 3rd party resins.

I print models that need to be dimensionally accurate. So anything that can show the accuracy of external dimensions as well as holes and interior features trumps pretty organic models.


#19

The prints are dimensionally accurate enough to satisfy the hundreds of customers I have sold my FEP based vats to world wide, those customers include designers, jewelers, dentists, university departments of engineering, research organizations and so forth. I am happy to let the the people who are interested in a durable low maintenance cost FEP based vat for the Form1+ decide for themselves whether this vat design fits their requirements when it becomes available at flexvat.com later this month or early next month.


#20

You asked us for suggestions and then tell us about your existing customers that unless I missed something aren’t using a Form 1 / 1+. Regardless of they are happy or not doesn’t matter to me. You would like us to be your customer. Help show us how this vat is superior to FL’s vat or the Z vat.

There are a few threads here that review the 3rd party resin problem we are all having. The resins aren’t printing accurately, the models are cracking, etc. You posted pictures using 1 resin and different profiles. This should result in different line thicknesses making some of your prints more accurate then others. This is why I asked if you could print something you can measure off of.

I am confused. Would you like our suggestions or not?