# How do I make a shaft collar?



## bluwolf (Nov 7, 2009)

I want to make a double split shaft collar bracket. I couldn't find a picture as an example. Picture something that clamps to something like a bike's front fork column but with extra material for mounting another bracket to it once the shaft collar is installed.

How do you actually make one? Drill/bore the hole and then split it? Doesn't sound right to me. Because you lose the width of the saw's kerf from the diameter.

Split the material, machine surfaces flat, drill and tap, bolt two pieces together, then drill/bore for diameter to be clamped?

Do you bore slightly undersize so the halves don't touch when you're tightening screws?

Mike


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## precisionworks (Nov 7, 2009)

Although a split shaft collar isn't hard to machine, it's usually cheaper to buy the commercial version. Stafford has a good selection & decent prices:

http://www.staffordmfg.com/Search.a...haft Collars&gclid=CJ6y46D5ipsCFRIeDQodT0eOpg

But it sounds like you need something special, so here's the way I've made them ...

Start with solid bar stock, and clamp the stock in the mill vise so it's near the top of the jaws. You can also let the stock rest on a T-slot in the table & use a step clamp on each end, but the drill & tap will hit the table if you aren't really careful.

Spot face, using an end mill, so the bottom of the SHCS has a place to bear. Without moving the part, drill & tap. Now move the table & do the other side. While you have the mill set up you may want to make one or two more (if there's any chance you'll need another).

Chuck the rod in the lathe & drill (or bore or ream, depending on the sizing & finish needed). Take a pointed tool & make a registration groove so the collar can be assembled correctly. Part off to desired length. Split.



> Do you bore slightly undersize


Collars are sized exactly to shaft diameter. The saw kerf leaves enough room so the collar can exert clamping force on the shaft.


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## bluwolf (Nov 7, 2009)

Thanks Barry,

The shaft collar will basically be rectangular to begin with. Then the actual split collar part will be at one end of that rectangle. The end away from the shaft collar part will be where I can mount something else off of it.

The part about cutting it after boring to the correct diameter is the part I was overthinking. I was also thinking that after cutting it with a saw that I would want to make a pass or two on the mill to clean up and get rid of the saw marks, mostly for asthetics. I was afraid that would start changing the dimensions of the hole too much.

Thanks again,
Mike


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