# Milling Cutter Arbor



## Nebraska Kirk (Dec 31, 2015)

I bought an arbor with an R8 shank to fit in my Bridgport, it has a 1" keyed arbor to accept horizontal milling cutters. I am going to get started into gear cutting and needed that arbor to hold the gear cutters.  The gear milling cutters in the smaller pitches all have a 7/8" bore, but I can't find one of those arbors with a  7/8" shaft, they are all either 1" or 1-1/4".  Does anyone know where I could buy one of those arbors with an R8 shank and a shaft to fit 7/8" bore milling cutters?


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## derf (Dec 31, 2015)

Make your own straight shank arbor. I have several that I built for slitting saws from 3/4" i.d. to 1.125". The advantage is that you can make the shank for the cutter fit             " snug", for no runout. The drive key is no more than a roll pin drove into the top of the arbor. The other advantage is length, sometimes you will need more stick out to reach a particular part.


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## Chipper5783 (Dec 31, 2015)

This is a pretty common issue.  You can pay more money and get exactly the arbor / gear cutter combination that will work - OR - make up a spacer sleeve.  There are a few different methods to accomplish this.  It is basically a "shop grown" solution.  You'll come up with one that works for you.  Let us know how it turns out.
http://www.hobby-machinist.com/thre...olute-gear-cutters-on-ebay.39415/#post-338148


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## Silverbullet (Dec 31, 2015)

Check on eBay there's some on there. A bit pricy but they do exist .


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## bob308 (Jan 1, 2016)

if you have a lathe make your own. make it with a straight shank and hole it in a collet or r8 tool holder.


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## Uglydog (Jan 1, 2016)

I bought an inexpensive shop made used one so I had something to copy.
Easy to make.
Would you like a sketch/print?

Daryl
MN


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## Nebraska Kirk (Jan 1, 2016)

After looking on ebay for gear cutters some more, I found a Chinese 10dp set with 22mm bore and a 22mm arbor with an R8 shank.


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## TOOLMASTER (Jan 1, 2016)

turn a 1" down...put the cutting bit in the mill vise and cut it like a lathe


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## Nebraska Kirk (Jan 2, 2016)

Toolmaster,  That is the best idea I have heard yet! Or it could be done between centers on a lathe.


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## RIMSPOKE (Jan 18, 2016)

I bought an arbor with an R8 shank to fit in my Bridgport, it has a 1" keyed arbor to accept horizontal milling cutters. I am going to get started into gear cutting and needed that arbor to hold the gear cutters.  The gear milling cutters in the smaller pitches all have a 7/8" bore, but I can't find one of those arbors with a  7/8" shaft, they are all either 1" or 1-1/4".  Does anyone know where I could buy one of those arbors with an R8 shank and a shaft to fit 7/8" bore milling cutters? 

HERE IS THE ONE USED IN MY GEAR CUTTING DAYS . 
IT HAS STEPS TO ACCEPT A NUMBER OF DIFFERENT BORE CUTTERS .  

I STILL HAVE 7 SETS OF EIGHT CUTTERS WITH VARIOUS PRESSURE ANGLES AND PITCH DIAMETERS . 
MOST OF THESE ARE NEW IN THE BOXES . THEY WILL BE GOING ON E-BAY SOON .


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## george wilson (Jan 18, 2016)

I just make the arbors for my horizontal attachment. I also made the outboard arbor support out of 2" thick aluminum with a bronze bearing inserted for the arbor. I bandsawed the shape,and cut a slit with a long bolt through it to tighten the support onto the ram of my Bridgey. Perfectly rigid.

The biggest problem is not making the arbor. It's making all the spacers that go on the arbor!! You can take spacers off another arbor and use them.


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## 4GSR (Jan 18, 2016)

RIMSPOKE said:


> View attachment 119603
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> View attachment 119602



You destroyed a 1944 Lincond Penny that was worth about 37 cents!    At least you could have used one of the altered cents they came out with!!!

How about offering the cutters you are fixing to sell on easyBone to use here on H-M first?


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## hman (Jan 19, 2016)

4gsr said:


> You destroyed a 1944 Lincond Penny that was worth about 37 cents!    At least you could have used one of the altered cents they came out with!!!


Naw.  Zinc just don't have no strength to it.  
Anyway, 37 cents is a pretty good bargain for a miniature gear any day of the week!


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## Moper361 (Oct 31, 2017)

Just a quick question does anyone know if the chineses involute cutters with 22mm bore fit on a 7/8 arbore ??as there is a tiny difference in size

Regards Nat


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## 4GSR (Nov 7, 2017)

Moper361 said:


> Just a quick question does anyone know if the chineses involute cutters with 22mm bore fit on a 7/8 arbore ??as there is a tiny difference in size
> 
> Regards Nat


You'll have to bore out the cutter by about .009-.010" to fit a .875" arbor.  Or turn the OD of your arbor down to .866"-.865" diameter.  Take your pick.
Ken


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## Bill Gruby (Nov 7, 2017)

22 mm = 0.86614 in. No it wll not fit without boring it as Ken said.

 "Billy G"


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