Machining Cork

Anyone who's read L.S sparey's "amateurs lathe" book will know he actually devotes a section to the machining of rubber and cork and how to make razor thin cutting tools for it.

I believe the example he used was the machining of rubber feet he made for a friend/client once. I'm now at risk of one of the bookworms tripping me up. I don't know why i bother. 

Michael W

Edited By Michael Walters on 02/04/2016 21:08:01

Ee, I remember the cork borers mentioned by Michael G well! They were nickel-plated brass tubes sharpened from the outside - the sharpening tool was a metal cone with a slot cut lengthways along the face in which a guillotine style blade rode, pivoted at the base of the cone. The borers cut a pretty clean hole without tearing. To my surprise they are still buyable on eBay, but easily made anyway.

I used to (occasionally) machine rubber at work by dunking it it liquid nitrogen before attacking it, but that would take it well below its glass transition point., so it worked like hard plastic, eg acrylic. But I don't think a domestic freezer would get it cold enough.

Of more relevance to the OP's problem though - I'd worry about just how 'non conductive' cork is at radio frequencies.? I'd have thought it would have a significant water content which could cause losses? Some sort of plastic, nylon or by preference PTFE might be better Just a gut feeling based on my experience of listening for the feeble RF signals from atomic nuclei - might be a different ballpark entirely!

Rob.

I am surprised nobody has mentioned cutting fluids, unless I missed it. I've found that water makes a big difference in cutting both cork and rubber.

Preach on about using cutting fluids, never heard of it.

I just meant try using water as a cutting fluid, sorry, trying to write in a hurry. Any one tried cutting tires with a knife will know how much easier it is with a wet knife, same for cork but less so.

!!! Next time I buy a bottle of fizz, I'll half expect it to be plugged by someone's finger.

Neil

Hi Allan, I have not had time to read all the posts so apologies if this has already been mentioned.

Lots of cork used in the fishing tackle industry in particular rod handles, these are machined to shape by grinding using a profile template and a similar process to a toolpost grinder on a lathe. If you have a few to do rig up a Dremel type tool in your tool post and use a small drum sander wheel.

Cheers John