UJK Parf Guide dog holes too tight

FWIW...for metal working the rule of thumb is that the reamer speed should be approximately half of the drill speed. That'd probably be a good place to start Mike. It'll probably be less than that because your reamer is stainless not HSS and yours has 1 flute not multiple flutes.

 
[member=11196]Peter Parfitt[/member] & [member=44099]Cheese[/member]  Thanks for the replies. Went to slower speed and got 20 to 30 holes this time before had to cool it down.

Mike

Added: OK - the holes I reamed slower are still too tight for the UJK dogs. If I re-ream them on high it's a nice tight fit. If I don't let the reamer cool after say 10-15 holes seems it has expanded enough to make the holes feel a little loose. Bit seems to be SS so have something to cool the bit. On my last of three slabs about every 10 holes I stuck the reamer in cold water then continued. This seemed to do the trick.
 
I recently purchased the UJK hole reamer from Axminster to deal with some holes that were too tight on my  Baltic Birch MTF made with the Parf Guide. Overall the reamer is a pretty food product, with a few caveats.

First, they probably should have made it out of tool steel instead of stainless. It would hold an edge better long term. That said, considering it should only need to be used on occasion the reamer will probably hold an edge just fine. I just get nervous when I see cutters made out of stainless steel.

The reamer works fine but you have to be careful not to let it chatter. As soon as that happens the holes will be a few thou (yes, Imperial!) too large and the dogs will be a loose fit. Fortunately I figured that out after reaming only 3 or 4 holes. To be honest, I had better success dealing with the tight fitting holes by running a Parf tall dog up and down through the hole a few times to burnish the inside smooth. A clamping tool like Peter shows how to make is helpful here.
 
Even easier is to put a threaded rod in the dog and use a drill to spin it.
I drilled and tapped my chamfer tool and use that with my drill. It does a great job of burnishing the hole, but unfortunately it isn't quite long enough to get the bottom 5mm.
 
Julie said:
Even easier is to put a threaded rod in the dog and use a drill to spin it.
I drilled and tapped my chamfer tool and use that with my drill. It does a great job of burnishing the hole, but unfortunately it isn't quite long enough to get the bottom 5mm.

Thanks [member=40122]Julie[/member] - can you post a pic of your jig?

Thanks
 
Here is my modified chamfer tool.
[attachimg=1]
 

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