3D printed parts and molds: A how to guide (of my experiment)

[thilokind]

I have made similar parts using a slightly different process. In a nutshell:
- 3D print core with PLA in one piece
- sand 3D printed part to a smooth finish and apply mold release agent (i.e. wax) or slightly sand 3D printed part and cover with electrical tape.
- Lay up glass fiber or carbon fiber and epoxide resin to the 3D molded core
- Apply peel ply
- Vacuum bag (breather ply, etc.) or wrap cling wrap film over peel ply
- let epoxide resin cure
- once cured, remove peel ply
- put part including 3D printed core in oven for 1 to 2 minutes at 300 F
- the PLA core will get very soft and rubbery - it now can be easily pulled out using pliers

[AX-O]

Thanks. looks like the only difference in our process is the oven. Pretty standard process.

You should post specifics on your projects so other folks can learn and see the possibilities folks (not manufactures, companies) have.

[BJohnson]

You must have meant 25 inHg vacuum. You would need an autoclave to get to 25psi.

Do you have a preferred source for the non-crimped-fabric you were using?

[AX-O]

Originally Posted by BJohnson

You must have meant 25 inHg vacuum. You would need an autoclave to get to 25psi.

Do you have a preferred source for the non-crimped-fabric you were using?

Good catch on the units.

Break

I got an email into Craig and Nicole for the part number and where to buy the carbon fiber. Will let you know.

[gofly]

Are you using Solidworks? Is that a plugin for it?

Thanks for posting!

Clark

[hgerhardt]

Originally Posted by gofly

Are you using Solidworks? Is that a plugin for it?....

Good time to remind folks that Solidworks is available free for EAA members. https://www.eaa.org/eaa/news-and-pub...or-EAA-Members

[Bill Rossmann]

Hi Axel great thread could you share with us the model 3D printer you are using and any problems to look out for..
Bill

[AX-O]

Originally Posted by gofly

Are you using Solidworks? Is that a plugin for it?

Thanks for posting!

Clark

This is Solidworks. You can get it from EAA as shown on the link provided in a post above.

Originally Posted by Bill Rossmann

Hi Axel great thread could you share with us the model 3D printer you are using and any problems to look out for..
Bill

I am using an ANET 8 printer. It was a kit that you build. Took about 5 hours to set it up. When I bought it the cost was around $250 without the filament. Now you can find them under $200. I spent extra on upgrading the printing surface on the bed and had a buddy print me some upgraded cooling nozzles, stand and knobs.

The biggest thing that I hate is that the plastic filament snaps off if you don't print in a while (approx 7 days). You then have to take things apart to feed the PLA back in.

I printed in quick mode that is why it ended up with small ridges. If you print in a different mode that part will come out smoother but will take much longer to print.

[AX-O]

2 nights ago I glued the 2 half together by placing a single layer of carbon on the inside seam. I covered it up with peel ply and let it dry for 24 hrs since I did not have the heater.

The inside looks like this after peeling the peel-ply.



Tonight I cut the flanges off and sanded them flush. After that was accomplished, i placed a 1 inch wide strip of carbon fiber on the seam and covered it with peel ply. I was going to use 2 layer on the outside but with one layer on the inside, it was very rigid already. 2 layers would have been a little over done.


The fiberglass intake you see on the background is the old one that came off Dave Anders' mold. It was used during the Reno air races and did not have an air filter.

[AX-O]

Originally Posted by BJohnson

Do you have a preferred source for the non-crimped-fabric you were using?

Nicole got back to me. They were using Vectorply carbon fiber when I was there building the wings, similar to this. Now they have changed to the same material made by a different manufacturer. It is Chomarat c-ply link

I have not had to buy it (well I did when the wing was built). Just using the scraps so far.