Not sure how many will ever need to do this but I needed to do it. I am planning on putting rear discs on my car so I modified a rear disc spindle in preparation for it. Since I am not ready for the rear discs but wanted to test my modified spindles I am keeping the drums.
Tools
10x1.25mm tap
11/32" drill bit
Tap socket drive adapter
3/8" ratchet
3" cut off tool
The rear disc spindle has the same bolt pattern for the disc shield as the drum back plate. The bolts sizes are different, drum spindle has 10x1.25mm vs disc spindle 6x1.00mm. So I drilled out the holes and tapped them.
Once the holes are drilled and tapped, the drum will bolt up but does not sit flat. There is bumped out spot that needs cutting.
Comparison of spindles
Start put with a step bit, drill until an 11/32" bit will fit
Next use an 11/32" bit and completely drill hole
Finally tap hole with an 10x1.25mm tap
After
Lined up but not flat
Shaded area needs to be removed
Bolted up and fitting flat
Tools
10x1.25mm tap
11/32" drill bit
Tap socket drive adapter
3/8" ratchet
3" cut off tool
The rear disc spindle has the same bolt pattern for the disc shield as the drum back plate. The bolts sizes are different, drum spindle has 10x1.25mm vs disc spindle 6x1.00mm. So I drilled out the holes and tapped them.
Once the holes are drilled and tapped, the drum will bolt up but does not sit flat. There is bumped out spot that needs cutting.
Comparison of spindles
Start put with a step bit, drill until an 11/32" bit will fit
Next use an 11/32" bit and completely drill hole
Finally tap hole with an 10x1.25mm tap
After
Lined up but not flat
Shaded area needs to be removed
Bolted up and fitting flat
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