"Building a welding JIG first" - design process and thoughts
- Thread starter BartRidesEternal
- Start date
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Practicing some soldering joints with brass worked out pretty good.
I'm learning it also by looking at other bikes. Bikes from builders and factories. Also old brazed bicycles are interesting to watch in regards to technique and style.
I can't remember or find when 'fillet brazing' became a thing, but in the past they just brazed lugless, joint only, no fillet.
Sometimes the brazing is on the inside of the other tube, for example in the bottom bracket. But there is much to learn here for me.
Looking at and thinking about how to braze, and how a frame is set up, I now realize that you can't stitch or spot-weld a tube in place like you can with mig welding.
I now know why these brazing builders use a welding table and clamps to first attach (and align) a few tubes to later fix it in the frame-jig.
That is why I am going to build another tool.
I don't have space for a welding table, not even a small one, so I'll have to fabricate a clamping tool to fix tubes in a adjustable angle.
These are for sale a lot, but is not what I am looking for.
Angle is fixed and different tube diameters need to be shimmed.
So I made a few concepts I will work out in 3D cad:
Feel free to criticize.
The main focus is to:
-Keep tube alignment, despite induced heat.
-Clamp various tube sizes with the centerline always centered.
-Clear the spot that needs to be brazed/easy to work around.
-Easy to move and put in a solid bike stand for working height.
Thanks for reading that!
I'm learning it also by looking at other bikes. Bikes from builders and factories. Also old brazed bicycles are interesting to watch in regards to technique and style.
I can't remember or find when 'fillet brazing' became a thing, but in the past they just brazed lugless, joint only, no fillet.
Sometimes the brazing is on the inside of the other tube, for example in the bottom bracket. But there is much to learn here for me.
Looking at and thinking about how to braze, and how a frame is set up, I now realize that you can't stitch or spot-weld a tube in place like you can with mig welding.
I now know why these brazing builders use a welding table and clamps to first attach (and align) a few tubes to later fix it in the frame-jig.
That is why I am going to build another tool.
I don't have space for a welding table, not even a small one, so I'll have to fabricate a clamping tool to fix tubes in a adjustable angle.
These are for sale a lot, but is not what I am looking for.
Angle is fixed and different tube diameters need to be shimmed.
So I made a few concepts I will work out in 3D cad:
Feel free to criticize.
The main focus is to:
-Keep tube alignment, despite induced heat.
-Clamp various tube sizes with the centerline always centered.
-Clear the spot that needs to be brazed/easy to work around.
-Easy to move and put in a solid bike stand for working height.
Thanks for reading that!
Way nicer than the odd fixture thing I made and added magnets to for tacking items
Thats also a great tip Captain.
I would love to see your fixture!
My current concept is made out of 12mm steel.
The four clamping parts need a little machining/cleaning the edges after lasercutting.
There are more stiff/rigid options out there, but this balances strength/stiffness, affordability and ease.
Details/thoughts:
-The large central holes are 25mm. I can solder/braze a tube there in one hole, so I can clamp this, whole thing down in a solid bike stand.
-The small square holes in the clamps are for 8mm nuts. Perfect to cut while the laser is working!
This is not my idea, I watched battlebots a while ago and saw the bot named Shatter. Its hammer utilized that idea, so if the threads get damaged, you can replace the nut. Easy as that!
Thanks!
Little update: I had a profile left, since I plan to change the fork jig to something more versatile.
I can clamp down anything on this.
Now I need to finish the brackets!
I can clamp down anything on this.
Now I need to finish the brackets!
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