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scottracing - 10/11/2018 7:47:11 PM

Yes they are a plastic material, sometimes they are wrapped very carefully in ptfe tape. Which is a lot of fun on pipework.
Ive used marbocote on pla and abs and it has released but pla is only good for 60 degrees max and abs isnt that much better. Maybe 80 to 90 at a push.

Hi. Scottracing.
I’m fairly new to the cf thing but have been have been 3D printing for several years. I use PLA as my go to filament but it’s temperature resistance can be dramatically improved by annealing it, a domestic oven is good enough.

Put the component in the oven. Increase the temp by 10 degrees every 10 mins up to 100 degrees. Leave it for about 1 hour, maybe longer if it’s a large part. Turn the oven off and allow it to cool slowly. A small change in dimensions my occur of 1% or 2% max. It not only is stronger, stiffer and has higher temp resistance but gives a better surface finish as all the layers are fused together better.

Hi Furrari
I have used PLA and annealed like you have stated too, i found that i needed to increase the infill greatly as the parts would deform greatly once cooking in an oven with a vac bag.
Luckily i have a Mark Forged printer so can use onyx for small tools and end use parts under the bonnet

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scottracing - 11/20/2018 8:46:23 PM

Hi Furrari
I have used PLA and annealed like you have stated too, i found that i needed to increase the infill greatly as the parts would deform greatly once cooking in an oven with a vac bag.
Luckily i have a Mark Forged printer so can use onyx for small tools and end use parts under the bonnet

Scottracing. I don’t use a vacuum bad when I’m annealing, as you say that can cause distortion. I just put each piece on a tray and cook it in the oven so there are no undue forces acting on the softened plastic. How this works on unsupported sections I don’t know. The longest/biggest job I have fully printed was an auxiliary diffuser wing 1.2m long. It was built in 8” sections, each part annealed and then the whole lot bonded together using mortise and tenon joints designed in the design stage. It was assembled on a flat board with each piece clamped down and to the next at the assembly stage. The clamping was done by making negative, matching, bridging pieces and clamping these down with bits of wood across them. There was a slight distortion at each of the joints bit I had made the outer layers 5 layers thick to allow for sanding. After sanding and painting it was carbon dipped.

It works very well, don’t know in terms of downforce as it was added to clean up the airflow at the back to stop the turbulence that picked up all the muck off the road and spread it all over the back of the car.

End component of the diffuser.