Yeah the vibrations are a bit of a concern with that design. I will be doing testing with that but I have another version ready where the brake mount connects to the dropout also from the upper part.
This was my idea initially but I just didn’t like how it looks. Let’s see how it works! Thanks for the feedback
Oh nice! You are one step ahead.
Short update. Some problems with the lugs as expected but 2/4 now made. Also starting to run out of time since I will be graduating at the end of this month 
Here’s some photos:
Looking really great! What type/size carbon tubing are you using?
Custom tubes made to spec from carbontubes.eu / caas.si
Damjan was really helpful with all the layup stuff etc. They were around 50-80 euros per meter so not as expensive as I thought.
This is nice work! Did you have any issues indicating in the part with the 3dp soft jaws? What type of tooling did you use to reach in for the deep bores?
Cheers,
Pete
The soft jaws worked much better than expected. I was a bit worried how accurately I could locate the part but it turned out pretty good. I measured the Z from the bottom of the soft jaws where the headtube bottom is located and the XY from the bore made in the first op.
There was a lot of problems with the long tooling and using the tall vice that enables 5 axis machining since our machine wants to make the XY motion at the tool change level before moving +Z axis. And also some problems with the “safe” positions making moves over the part when the table is at home position. Because of that I couldn’t use all the tools and holders that was planned.
Most of the deep material removal is done with just drilling and then using longer 20mm end mill. This is not fully optimized in regards to weight yet, since there is some excess material inside the deep holes. The weight is currently around 400g and is acceptable for the proof of concept.
Here’s some renders of the frame while we are trying to figure out the problems with the bb lug.
Some teasers of the bb lug mid OP1:
I think it’s gonna look good
I’m going to take some well deserved time off for a week! Happy new year to all of the readers!
As always any comments, questions or suggestions welcome.
Finally the bb lug is done It was by far the most problematic part to make. Starting to work on the jig and hopefully get to bond the frame soon!
wow! so cool! It’s almost a shame to put that beautiful piece into a bike. How were you able to get the internal bores and sleeve joints so smooth?
They are machined with a boring bar
For the bonding jig I’m planning on using a welding table with machined parts to locate the components. Made some parts today and hopefully get to do some dry testing soon to see if it seems like good to go.
Got the tubes cut and prepared the bonding surfaces. Did some dry fitting and I have to say that it looks so amazing to finally see it together. Still need to prepare the bonding surfaces on the lugs and make a small jig for the T joint. Hopefully can bond it together early next week!
This is looking very very polished and professional. Makes me wish I was still in school.
Looks amazing! Are you going to use any fiberglass sheets to prevent galvanic corrosion? Or relying on a glass bead filler?
Glass beads and hope for the best
Looks very nice. How did you figure out the material thickness etc? Did you do any stress simulations?
