Badly warped SLS model

My architectural firm made our first foray into the printed 3D model world with this project. Unfortunately after opening our package from Shapeways we see this. This is a floor plate for a building that should be flat and as you can see is terribly warped. This twist was not part of the submitted model.

A couple questions

1. Is this a printing error, would Shapeways have sent this out in this condition without back checking against the submitted model?
2. Was this a result of packaging and shipping? Our company is located in Phoenix Arizona and it is possible the package sat in a very hot truck for an extended period of time.
3. Most importantly are there any post production techniques we can use to flatten out the model? I've read about hot water immersion or heat guns/blow dryers but I'm unclear if this will work on a SLS model.


Any help the community can provide would be greatly appreciated. Hopefully there is something that can be done because at this point the model is a total loss as we would never be able to present this to our client.

Many thanks,

-John

The hot water trick appears to have helped here though I was not sure it would work for nylon when I suggested it.

This is a well known issue that occurs with SLS 3D printing. This happens to large flat surfaces and is the result of uneven cooling.

1. Is this a printing error, would Shapeways have sent this out in this condition without back checking against the submitted model?

They probably thought that you could attach it to a flat surface or something like that.

2. Was this a result of packaging and shipping? Our company is located in Phoenix Arizona and it is possible the package sat in a very hot truck for an extended period of time.

That's possible, but I don't think this was the case.

3. Most importantly are there any post production techniques we can use to flatten out the model? I've read about hot water immersion or heat guns/blow dryers but I'm unclear if this will work on a SLS model.

Yeah, there are ways, but it's tricky because any uneven cooling that occurs will make it warp in other directions.

What I would do is write to service@shapeways.com and get them to give you your money back because I don't think they can print this perfectly flat. I would then try printing it without the floor. On the other hand. if I needed to get this to a client on time I would just get some rigid material like 1/2 inch plywood and then glue it down with some contact adhesive and some clamps.

Another way to straighten it you might try that I thought of just now is use ultra violet light curable resin. What I'm thinking is you would paint a 2 inch wide swath of the resin onto the bottom going from a corner to the center. Then you would bend by hand in the opposite direction of the warp and then cure the resin with the UV light. Most photocurable resins cure almost instantly so the process would go quick. Then the pressure would be released. If the didn't get that section of the warp straight then you do the steps again until you got it just right. This would be analogous to straightening a bicycle rim vie tightening and loosening the spokes. if you're ever done that or have seen it done then you know what I'm talking about.

I've bent things back into the correct shape with a hair dryer/heat gun. If you could weigh down the corners while heating and allowing it to fully cool it might stay flat.

You could also glue it to a nice flat piece of wood, you could make it look intentional if you had the time.