Messed about with my jig a bit tonight and thought we should have a thread for people to post their successes and failures and DIY jig building.
This is what I started with,
The uprights weren't very secure and went out of adjustment very easily. I think @biggles had this issue with his jig too.
The bottom bracket also gets in the way of the mount for the seattube upright and the rear axle was the fixed point so if I set it up then wanted to adjust chainstay length it mean moving everything (and it inevitaby going out of adjustment as I moved it...) and because of the weight of the uprights I'd been horsing down on the bolts that hold the pivot blocks to the base and the t nuts had chewed up the channels in the extrusion a bit making adjusting it pretty difficult.
All I'd had to make for that though was the pivots for the uprights (cuboidal blocks of ali drilled a few times and faced to be square on the lathe,'cones' for the head and seattubes which I just did stepped rather than tapered as the lathe I have access to has a terrible compound slide and the axle holder which was again just a drilled and faced block of ali.
Cost of that jig was around £100 I think, main costs being 1x 1m length of 2080 and 2x 750mm lengths of 2060 extrusion.
This is what I've come up with tonight,
I can now adjust front and back end geometry independently and (I think) the frame will come in and out of the jig more easily now.
Also added a little mount to the back so I can hold the jig in my workstand as well as the vice.
This design uses only 1 of the 750mm bits of 2060 so would actually be cheaper than the original iteration.
Who else has a home made jig to show off?
Will the extrusion parallel to the seatpost be in the way when you are welding/brazing?
It might if I wanted to do full fillets in the jig but I’ll really just tack in the jig then remove the frame from it to do the fillets as this allows me to check alignment better I feel.
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