ABS prints cracking and bending directly after or during a print

[sajawors 0]

Hey there. I got great help last time, so hopefully will do so again. ?

 

I'm printing lots of stuff on ABS with PVA support and have noticed, particularly on jobs where i DO generate support, that stuff is already cracking. I can take pics if needed, but don't really know how else to explain it. It's a completely flat surface with a hairline fracture in it. And there are several like it on each side of the object.

 

And then yesterday we were printing a plane for another project and as it was printing the support, the support was coming up off the bed as it got thicker, which then made that side of the tail curve upward when it should have been flat. Is there something special to using the PVA support and / or ABS? I'm selecting those materials from the menu when I load them. The PVA is ultimaker branded, but the ABS is an off brand but has been fine on jobs without support. 

 

Thanks.

[Brulti 177]

ABS and PVA is labeled 'Experimental' by Ultimaker. Meaning that you can try it, but there's no guarantee that it will work. The only support that is guaranteed to work by UM with ABS is ABS.

[kmanstudios 1,120]

I have never gotten ABS and PVA to work together as it wants to warp off the PVA surface.

[sajawors 0]

So then what do I use for support material when printing with ABS? The stuff we're printing is going to be heavily handled and beaten up by children so my understanding was that ABS was the way to go, but we're definitely printing shapes that need support. We have PLA, ABS and the PVA natural, dissolves-in-water type stuff that's meant for support. 

[kmanstudios 1,120]

I am gonna stick with 'Depends.'

 

Not being sarcastic.

 

1. Depends on design. Spindly things are going to be an issue no  matter what.

 

2. Depends on the construction of your infills and walls

 

But, you can also look into nylons and Tough PLA. I had a quick look at the UM TPLA and it rocks. BUt you would have to test this based on the above.

 

So, to better answer your question, are you prototyping for design release? Are you making end use products? What type of designs? I mean, look at how design changes with the type of action forecast to be placed on objects by age range and, they use injection molding. Does it need to bend or be stiff? Age range aimed at....all sorts of things. ABS may be your best bet, but it is also one of the more difficult things to print with. That is why there is such a push to find solid alternatives.

[sajawors 0]

So it's for scientific studies testing memory development in infants and toddlers. They have to meet pretty strict measurement requirements and have to withstand a couple hundred babies handling them, beating them around and such. The discussion was that PLA wouldn't withstand that over time, but ABS would. But we need specific shapes to make the tests work (they're simple 1, 2, 3 step tasks that give a pleasant outcome so the baby will want to do it again (ie put a ramp together in 2 pieces, slide the plane down the ramp and watch it go weeee)). There also might be something to said for babies putting ABS in their mouths. If I use CPE (can't remember if it's a roll of CPE or CPE+ that we have on hand) or Nylon, will the support work better with that? Thanks.

[kmanstudios 1,120]

Nylon works wonders with PVA. And, I would investigate the UM TPLA. I really like it. It will replace all prints that I make that get painted....with a few exceptions.

 

And, Nylon can be dyed to get some really striking colors with food safe dyes.

[Brulti 177]

Print with Nylon + PVA, definitely.

 

Nylon is very solid and resilient while still being flexible enough to be handled roughly without breaking. And it is made to be printed with PVA supports.

 

ABS is more solid than PLA, but it's much less flexible, and it will break much more easily when handled roughly, as kids can often do. Heck, I managed to break some ABS I've printed by twisting them just a bit.

[DF-Werkzeugservice 9]

Hi,

 

I'm printing lots of ABS with support material. After experimenting with many supports, I sticked with High-T-Lay by Lay Filaments.

This is not officially supportet as it's not a UM material but it works very good. It's a kind of high temperature PVA. Essential for the bond is a good calibration of the X/Y shift of your printcores and the Z difference.

 

When the calibration is fine, it bonds pretty strong to your ABS print, it also prevents supportet parts from warping.

It dissolves (pretty slow) in warm, circulating water.

 

Despite it's a PVA based material, I get besser results and less clogging using the AA Core.

[sajawors 0]

Yeah, for the job I needed to get done that week, I ended up trying ABS with ABS support and it worked amazingly. Thank you for the response though! We're kinda stuck with the material we have on hand atm.