Hole Saw for Rubber Stopper? 1

[tharding247365]

Any suggestions to drill about a 3/4" hole through a rubber stopper? I'm thinking a really fine tooth one, but I haven't done this before. About a 2" deep hole.

 

[btrueblood]

Get the kind used for cutting ceramics/concrete, with the abrasive where the teeth normally are. Oh, and try putting the rubber in a deep freeze before cutting.

 

[tharding247365]

Ironically enough, that's just what I put on order yesterday! Glad I'm going the right route. I'll confirm if this works for me

 

[Compositepro]

All of the hole cutters for rubber that I have used or seen are thin walled tubes with a sharp bevel on the end. The tube is slowly rotated as it is pressed into the rubber. A little oil will greatly reduce friction during cutting. I actually had to make one a few weeks ago. It was easier to make one than to order one.

http://pubs.acs.org/doi/abs/10.1021/ac50016a719?journalCode=ancham

 

[3DDave]

We had some production guys try to open a .375 hole to .500 in a chunk of rubber. They ran a .500 bit into the hole and it remained .375. They froze it and then tried the drill again. Same result. I don't know if they tried liquid nitrogen. They did try heating a .500 rod red hot. Don't try that. It took a while to air out the 250,000 square foot high-bay factory area.

I would definitely go for the thin walled tube with an external bevel. Use care in retaining the part so the hole is the correct shape after release.

 

[tharding247365]

Using a diamond tipped core bit worked beautiful! Water and soap as lubricant.

 

[Sawbux]

Did this in College to make rubber feet for some equipment. Freeze the rubber with dry ice, then drill.

 

[btrueblood]

FWIW, CPros is (as usual) not wrong, but the abrasive tipped tools just work faster than sharp clean edges, and with less compression/distortion of the rubber occuring, so they tend to cut (abrade) a straighter hole, if messier due to rubber crumbs getting everywhere. Also, rubber is annoyingly good at making sharp steel tools dull very quickly...

 

[tharding247365]

I also did not have to freeze. Just a diamond coated hole saw. Same bits I use for glass. Came out pretty straight using a cordless drill, I need to get a drill press.

 

[racookpe1978]

How many do you have to make?
What accuracy is acceptable?

 

[berkshire]

Many years ago I worked for a company that machined rubber, holes were cut with an abrasive saw under a flood of coolant, the coolant carried away the rubber crumbs,
B.E.


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