# Over-sized 1-1/2" by >.020" 1/2" shank bit needed



## knotbrush (Jun 26, 2013)

Hi,
I need bits to cut a 1.520" to 1.531" by .0625" deep by 2.75" long slot in KD Beech. The part will have a 1.5" wide part that fits in the slot and is screwed in place. It wouldn't be a problem except part "B" if often up to 0.025" over. With enough pressure on the clamping it WILL fit but it slows down the operation and is a general PITA. I need to do 500/day. I thought of planing part "B" but it's too irregular so a bigger slot is the best way...I think. The parts can have a bit of a sloppy fit.

The 1/2" shank bit is in a Powermatic shaper running about 12k RPM.

Where is the easiest and quickest place to get over-sized bits?

One thought I have is to remove the carbide from a standard bit, re-index the carbide to a larger diameter and silver solder them back in then grind the OD in a fixture on a surface grinder. (I am lucky to have a full machine shop) But, I would MUCH rather get an off-shelf item.


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## Mike (Nov 22, 2004)

Call Whiteside and have them build you a bit to your specs. 
The amount of time you save will be worth much more than the cost of the custom bit.

Whiteside Machine Company


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## knotbrush (Jun 26, 2013)

Thanks Mike! If you cut most of your hair off...we could be twins!


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## Mike (Nov 22, 2004)

Tom, spend a few minutes and put some information in your profile. We check this to see what state you are in and get a general idea of what tools you have to work with. This let's us give better answers.

My twin? You can attach a photo by clicking the go advanced button and then manage attachments.


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## jw2170 (Jan 24, 2008)

G'day Tom.

Welcome to the forum.


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## Daikusan (Apr 12, 2013)

Mike said:


> My twin? You can attach a photo by clicking the go advanced button and then manage attachments.


SOMEBODY HELP US!!! 2 Mikes??? JK


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## Willway (Aug 16, 2012)

+ on Whiteside. Cost on custom bits is less than you might think, and made right in the US.


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## damnitboy (Mar 3, 2012)

Howdy Tom, Mike is absolutely right don't be afraid to buy custom made router bits. There are even many small local shops that build special tooling at a more reasonable price than the big manufacturers as well. I have a small machine shop so I can build my own Shaper Cutters, Router Bits, Profile knives etc. I would guess you could have what you need for right at $100.00. If that is cost prohibitive. use a 1-1/2" bit and step it to the side to get a greater width of cut. Two cuts take more time but you can jig up with a guide pin and a slot to guide it to the right width, that will go pretty fast. If this is a manufacturing process though, spring for a custom bit.
-Eloy


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## knotbrush (Jun 26, 2013)

We're doing a dual cut now with a sliding box jig and two strokes. I want to do a one-pass through the cutter and continually feed the blocks so as they fall into a drum at the other end. Yep, I'll get a few custom bits, I decided it's not worth the time to remount carbides and there if most definitely a safety factor. Thanks!


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## damnitboy (Mar 3, 2012)

Howdy again Tom, Another option that would be less cost is get a bit the next size up and side the diameter down to what you need. Any tool shop can do that just put a 15 degree radial clearance angle. The way your tool shop can check this is use a dial indicator and rotate the bit until you get a .015" drop on 1/16" of rotation and you will be very close to a 15 degree radial clearance primary if necessary grind a secondary clearance angle to produce a 1/16" wide land on your primary land
-Eloy


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## knotbrush (Jun 26, 2013)

damnitboy said:


> Howdy again Tom, Another option that would be less cost is get a bit the next size up and side the diameter down to what you need. Any tool shop can do that just put a 15 degree radial clearance angle. The way your tool shop can check this is use a dial indicator and rotate the bit until you get a .015" drop on 1/16" of rotation and you will be very close to a 15 degree radial clearance primary if necessary grind a secondary clearance angle to produce a 1/16" wide land on your primary land
> -Eloy


I hadn't thought to grind a dual angle, what would that improve? I did silver solder a bit to a bigger diameter and regrind to +.030". It was a lot easier than I thought and turned out perfect. I'l do a few more for back-ups. The biggest perceived problem was in the silver soldering and keeping the insert in position. I made a simple jig and have #10-32 screws to keep pressure on the carbide. The trick is to have the old silver solder perfectly removed and then have everything perfectly clean. I reground the bit on my surface grinder with an indexing head holding the bit. I knew to just break the edge on the carbide with a diamond stone.


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