Deformation of prints due to continued (unwanted) curing

Just had a client call me who is very unhappy that the prototype print I gave him yesterday has warped out of shape overnight. Its basically a box with a removable bottom section, so pretty flat and only has a 1.5-2.5mm cross-section. It was fine on my desk for the 3 days before I passed it onto the customer so not sure how it could have warped so badly in a 24 period after seeming stable for 72 hours previously. Is there anything I can coat my prints in (other than primer and paint) to prevent additional curing and warping?

Hi Jason,

I would put the piece in a place where it has direct sunlight, also I would advise using a uv lamp to additional cure the parts faster.

Hope that helps



Hi Paul

Funny - I replied to this yesterday but it doesn’t seem to be here. I always post cure in a UV booth, but in this instance the warpinf took place 4 days after I printed it, and less than 24 hours after I handed over to the client. I’m now looking into clear coat lacquers that block UV - not sure if it will work but its got to be worth a try.

We’ve used a variety of UV clear-coats to help inhibit curing. Some have been recommended in the forums before. I know one that we’ve used in the past is Krylon UV resistant clear-coat.

Hi Sam

Have you tested the resins for UV stability after initial curing? If so was there a particular colour that was more or less prone to warping?

This may be a touchy thing to ask the client, But I wonder if they left the part in a car in the sun. While it is not a thermoplastic, cars get pretty hot with closed windows. Otherwise really surprising it would suddenly warp after being stable for several days.

Have you seen the part in person? It might provide evidence of what happened.

Nope, the models were indoors at all times, and as I say it was less than 24 hours from handover.

When my prints warp its always immediately but I have many that are fine for a day or two and then suddenly burst or crack all over which is really depressing!

What colour resin are you using when they suddenly deform? Do you post cure? Are they particularly thin in cross-section? do you use a UV varnish to reduce additional UV exposure?

I dont think its been any color worse than another but MakerJuice resin does alot worse than Formlabs resin. Thin or tiny features are worse. I dont post cure but I paint most of my models and rather I paint them or not I always finish with a UV shielding clear coat either matte or gloss. I should also mention that I have had tiny parts that come out deformed that straighten themselves out after sitting overnight! To reduce hollow models from exploding I drill holes in them ASAP which works as long as their not too thin.

Hi Folks,

I would like to report a similar issue except that it happened over 2-3 month. I printed really simple piece both them flat, I put them under a UV lamp for final curing (3 hours). Then I stocked them in a transparent box in my office away from sun illumination (24/7 air conditionned to 20 °C) and here I found them this morning (cf photos).

althought I did not think to coat them with anti-UV, but for our application (biology) it may raises further problems.

I’ll gladly pay attention to any suggestion