Two New Engineering Materials: Grey Pro and Rigid

They aren’t advertising the new grey as providing more impact resistance. It’s “more accurate” and more resistant to “creep” under load.

Because I don’t have accuracy issues or creep issues the new reinforced material is what has me excited. I’m very interested to see how the material performs on thin sections. It’s harder and tougher than the other resins and should hold reasonably sized threads better.

Pretty much any thin walled part that is dropped is going to break. If you need more impact strength it’s probably better to go with a mold and a good casting resin.

For the things I do (both the real job and hobby job) a reinforced high temp resin would be ideal. Add tensile strength to the HT’s hardness and temperature rating and I’ll be very happy. Even if the HDT drops to 200c. If the materials team says the HT will stick to glass it’s worth looking into.

According to this Cambridge engineering page, higher elongation should make the material less brittle. Or at least that’s one aspect of brittleness. If elongation is double that of standard resin, then it should be meaningfully less brittle? In any event, I will ultimately find out since I ordered a few cartridges in addition to Rigid (which I definitely have uses for).

Yes elongation is related to brittleness but so is impact strength. This is a simple schematic to illustrate what an IZOD impact strength test consists of. Basically it’s akin to a drop test, higher value is better ( which is why Durable and Tough don’t break when dropped (bottom of the page) ) . Grey Pro has a 25% lower value than Clear/Grey, it’s actually closer to High Temp and if you ordered a sample of this resin you know it’s VERY brittle (broke it by dropping it on linoleum from 50cm), which is what troubles me.

THe advertised advantages as @FredB wrote are accuracy and resistance under constant load, which are both things Tough isn’t very good at (but still fairly decent) but Grey std is already pretty good at both these things… the issue is, especially for stability under constant load, there is no official metric to compare the resins.

Yeah, I guess I thought from the initial post that “moderate elongation, and deformation resistant material” meant something in between standard and tough. I’ll give it a try and see what comes of it.

I don’t have any concrete dates for when sample parts will be offered for Grey Pro and Rigid Resins, but I’ll let you know when I do.

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We haven’t done formal testing here though subjectively (and somewhat objectively) Grey Pro holds marginally improved tolerances as compared to Grey v4. While printing, it’s more resistant to deformation from the peel which results in better tolerances.


Can we use these new resins with the standard tanks? I want to test them out, but it looks like I cant get an LT tank for two months…

Agreed on the High Temp resin and fiber

On a whim, I knocked out a small cover for a small RF amp and met the spec’s although it had problems in the test fixture from the clamps during thermal cycling. I’d guess that introducing fibers into the High Temp resin would improve compressive strength. In actual use, there wasn’t any issues due to the low forces involved with 1-72 screws mounting the cover. For those interested, we applied a black, high temp paint on the exterior and a metallic silver paint for the interior as a ground and RF shield. I normally machine housings (aluminum) for this customer, but would love to print some quantities of these covers as well.

Looking forward to seeing a few RC aircraft constructed in Rigid.


The new resins are unfortunately a bit more aggressive with the PDMS and will require the LT tanks.


Any plans to ramp up production for the LT tanks? Maybe shave down the leadtime a bit?


What’s an LT tank?

It’s a long term use tank, designed to be used with some of the more aggressive resins. Ones like High Temp and Dental (now also Rigid and Grey Pro), which cloud the normal resin tank really quickly.

How is that accomplished. And can it be used with the other resins as well?

Formlabs News is the thread I’m most interested in, but it is difficult for me to handle the quantity of posts in my email inbox.

Does anyone know how to receive a daily digest of this Formlabs News thread via email in lieu of every post? I use this function in other forums but cannot find the per-thread (or even forum-wide) digest option in the FormLabs forum.

I apologize for the interruption in the conversation flow and appreciate your help.

I’m not quite sure how it’s done (I think its a fluoropolymer (?) in the tank instead of the silicone), maybe @Frew can chime in here!

I can say that it has held up much better to the High Temp than previous tanks have. That resin burned through my tanks too fast, so this was a much needed improvement!

The tray can be used with all resins. It lasts much longer with standard resins and should be well worth the added price of the tray.

@Frew will the new materials refuse to print on the current resin trays? Or will they just come with a limited life?

If only i had rigid before printing my last project…

Friends’ startup is working on a wearable streaming cam, i was printing the case and clip prototypes - both, of course, are nothing but thin features. Regular Grey prototype broke for them after a week or two. We ended up using Durable, which works, but is slightly too bendy. Rigid seems like it would’ve been perfect.

Out of curiosity, how well does Rigid endure high temps? Say up to 150 deg C?
If i get some for their next prototypes, i wonder if i could (ab)use some for printing FDM printer parts :stuck_out_tongue:

@Frew are the LT tanks in any way inferior in terms of quality for the standard resins? I ask because I mainly use grey v3 (4) and if the results are the same it’s a no brainer!