Resharpening reamers

[Technical Ted]

Looks like I found the link...

Operator's Instruction Book, Cincinnati No. 2 Cutter and Tool Grinder : The Cincinnati Milling Machine Company : Free Download, Borrow, and Streaming : Internet Archive

Operator's manual for the Cincinnati No. 2 Cutter and Tool Grinder (including machines having power table traverse). Publication No. M-1951-2. Supersedes...

archive.org

That's a good book. I added it to my "library". Maybe that will help the OP more, because it goes into reamers with more of a step by step instruction and finer detail than the Norton book. The Norton book just gives you the "data" and leaves the reader with a lot more to figure out on their own than this book does.

Nice find!
Ted

 

[Technical Ted]

This video is for a tapered pin reamer, but gives a very good idea of how to set up to grind the sides of a reamer, especially if you don't have a spinning fixture. Notice he has the Norton Handbook I posted on the T&C grinder table.

Ted

 

[francist]

That's a good book. I added it to my "library".

Yeah it is. I found it a while back while looking for information on resharpening horizontal milling cutters and such (which I still haven’t fully pursued) and hung on to it ever since. A lot of it is kind of out of my league but I can dare to dream.

-frank

 

[9t8z28]

Page 33 clearly states the cutting angles for the different types of material desired to be cut. It's part of chapter II, Milling cutters and reamers. You'll have to read that chapter to learn and understand how to do it and how to set up your equipment to get the desired clearance angles. Chucking reamers is also covered on page 53, but pages 36-39 instruct you how to produce the angles. There does seem to be a page missing. Here's a copy I took a picture of from my book.

Ted

I used the table of contents to find the section on reamers when I should have just started reading through the pages. I guess I now see where my weaknesses are when searching for the info I need! Thank you for posting this and taking the time to show me where to look.

 

[9t8z28]

This video is for a tapered pin reamer, but gives a very good idea of how to set up to grind the sides of a reamer, especially if you don't have a spinning fixture. Notice he has the Norton Handbook I posted on the T&C grinder table.

Ted

Yes I watched this video a few times but found that it didn't go into the details I need but it was still helpfull.

 

[9t8z28]

Looks like I found the link...

Operator's Instruction Book, Cincinnati No. 2 Cutter and Tool Grinder : The Cincinnati Milling Machine Company : Free Download, Borrow, and Streaming : Internet Archive

Operator's manual for the Cincinnati No. 2 Cutter and Tool Grinder (including machines having power table traverse). Publication No. M-1951-2. Supersedes...

archive.org

Thanks for posting. I ran out of time to read through the Cinci book. I will try and look at it today.

 

[Technical Ted]

Thanks for posting. I ran out of time to read through the Cinci book. I will try and look at it today.

This book explains things much better than the one I posted. If you have sharpened the sides of end mills, it's basically the same thing clearance wise... You could even use an end mill jig (which I have for large diameter reamers) and it works fine. The tricky part is lowering (or raising) the cutting edge you are sharpening the correct distance to give you the clearance angle you want, and that changes with whether you are using a cup type wheel or a round wheel (as the books show). The old hands who taught me a lot always said to "pick up the old grind", which on a narrow land can be harder than it looks.

If you have a lot to remove off the sides it's faster to spin them down to near size and cut the clearance afterwards.

Ted

 

[kb58]

Just thinking it through, I don't see how a reamer can be sharpened to its original size. Is it possible? I'm assuming that the wear takes place on the leading edge/outside diameter of the reamer.

 

[Technical Ted]

Just thinking it through, I don't see how a reamer can be sharpened to its original size. Is it possible? I'm assuming that the wear takes place on the leading edge/outside diameter of the reamer.

Typically, reamers are sharpened on the leading cutting angle only. This is usually ~45 degrees. The front angled cutting edge is where all the cutting is done. The sided (flutes) are only ground when the reamer is in really bad shape or a smaller size is required. Once ground, the reamer cuts smaller.

So you are correct!
Ted

 

[Illinoyance]

I have done it on larger reamers with a center in the end. The difficult thing was finding specs for the clearance angle.