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Hole for Motor Run Cap


2014-10-28 11:45 am
What have other members used to drill a 2" hole to install one of these big motor run caps upright on their case. I have a 2" height case and because of a larger lip on the cap it will not go underneath and I would rather have it upright taking up less space. Another question is how to mount this cap after getting the hole.


2013-03-02 9:16 am
Co. Clare
I depends on what material you are using but if it is steel or aluminium I would say that the best is a step drill.
Second choice for me would be a hole saw and third choice would be to drill a series of small hole then cut and file.
Other materials, I would use a router.
What did you use for the tube socket holes?
For securing it underneath, there are special brackets available which go around the cap and fix it to the underside.
A jubilee clip could be adapted to do the same thing.


2014-10-28 11:45 am
I used a step drill for all the other holes, I have 2 sizes but neither is large enough for a 2" hole. The material is Aluminum. Drilling small holes and filing is the way I do the IEC socket but I am afraid when I finish doing this in the top plate is will not be pretty. I am sure I can find a 2" metal bit but then I know from experience it is going to be pricey.
Hole saw. Usually cheaper than 2" step drill bit.

For mounting, I used capacitor mounting clamp under the surface, like the one shown below.

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2010-11-01 3:24 am
Another idea is a fly cutter. Harbor Freight has them. Grizzly, too. The can be adjusted to any diameter in it's range. I've used the single cutter and it takes a steady hand on the drill to keep it from binding. They make a two cutter model but I haven't tried them yet. Another idea might be to flatten the rim on opposite sides, to make it fit, so long as you don't cause a leak:(