Thread: Bike Bobber
View Single Post
Old 05-01-2014, 07:45 PM
massdrive's Avatar
massdrive massdrive is offline
Motorized Bicycle Elite Member
Join Date: Oct 2013
Location: Las Vegas
Posts: 455
Default Re: Bike Bobber

So the brake flange cup is finished and the brake arm is ready to shape. I'm using the slit and weld method to bend the brake arm into a nice smooth 3 1/4 in. arc. Why 3 1/4 ins.? Because I'm installing a 40t rear sprocket that is... 6 1/2 ins. in diameter. It is little things like this that can make the components of your bike mesh together.
To start I made a simple template out of poster board to follow when bending the arm. As you can see unless you do this everyday it can be difficult to gauge the width and frequency of the saw cuts. So I've made some more work for myself, but it will all work out in the end. After tacking it together on one side I welded the inside diameter first. This will help stabilize the piece when I finish weld the side I tacked.
Attached Images
File Type: jpg 28_weld crook neck.JPG (455.1 KB, 44 views)
File Type: jpg 29 made a pattern out of poster board to follow.JPG (212.4 KB, 50 views)
File Type: jpg 30 slitting the arm.JPG (254.5 KB, 44 views)
File Type: jpg 32 tack welding the arm every 2 or 3 slits.JPG (120.3 KB, 45 views)
File Type: jpg 33 done sliting and tacking.JPG (237.0 KB, 45 views)
If you have to force it there must be a better way
Reply With Quote