John,
I have never put an EVA grip on a rod where it needed to be stretched. I simply don't see the need to try to stretch something out, when it is very easy to ream out the grip to the desired size.
For reaming, I have always used circular files of various sizes to accomplish the task. But, the other type reamers like the dram reamers and sand paper based reamers also work very well.
To keep the hole centered, use a ream and slip technique.
When reaming, wear a pair of cloth or knit gloves. I buy the brown jersey gloves by the dozen and I also buy the white knitted gloves by the dozen. I almost always have a pair of gloved on my hands when working with sand paper and glue. If not those type of gloves, I wear nitrile gloves in my size. In my younger days, I never wore gloves and as a result had to do a lot of hand cleaning, and also doctoring up cuts and nicks that I received as a result of my foolishness.
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www.fleetfarm.com]
[
www.fleetfarm.com]
I have large hands so I purchase XXL gloves to fit:
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www.harborfreight.com]
For smaller hands:
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www.harborfreight.com]
But, when reaming EVA with a glove on the hand that is holding the EVA and the drill in the other hand that is doing the reaming - I simply insert the reamer and go to work. The secret is to intermittently let the EVA grip slip a partial turn in my gloved hand as I am reaming.
The idea behind this is that if you are reaming and happen to be slightly off center, as the Eva grip slips around the full 360 degree circle or rotation, the reamer evens out the enlarged hole.
This is exactly the same principle as happens when I use my lathe to drill a perfectly centered hole in the end of a circular object being held in the jaws of the lathe chuck. Chuck the object to be drilled securely into the chuck of the lathe. Then, secure the drill bit to be used to drill the centered hole in the chuck that is in the tail stock of the lathe. Then, with the work spinning at the appropriate speed, advance the stationary drill bit into the spinning object. Since the object is spinning around the stationary drill bit, the hole that is being created has no choice but to be perfectly centered.
This is exactly the same thing that happens when one reams an EVA or other type grip with a spinning reamer. As the spinning reamer is going into the grip, the intermittent rotation of the grip being reamed will cause the enlarged hole to remain perfectly centered.
Best wishes.
