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CBN Grinding wheel wrong bore

Tiny James

Full Member
Joined
Oct 13, 2020
Posts
194
Location
Rugby
First Name
James
I'm after some advice or help tracking down Bushings for my Grinder

I have a grinder with a 12.7mm shaft and a Tru-Grind CBN wheel with a bore of 15mm, now I can't believe I'm the only person that has had this problem.

Axminister sell bushing for larger bore's but not the 12.7 mm bore.

the wheel dimensions are 150mm x 40mm x 15mm with a bore of 15mm

I could exchange the wheel for a 150mm x 25 mm x 10mm with a bore of 12.7 but I really feel this wheel is to narrow for a 1" skew chisel and this is not a route I want to go down

So does anyone know of a supplier of the bushing needed or a replacement flange with the 2.3mm step in it.

even a fix for this

James
 

monophoto

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Joined
Dec 17, 2013
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67
Location
New York
First Name
Louie
I'm in the US where we use an archaic system of measurements - which has the advantage of offering far fewer options to choose from. That being said, I suspect that 12.2mm corresponds to our 1/2" diameter, while 15mm corresponds to our 5/8" diameter. Woodturners Wonders offers this Shaft Adapter Bushing that might do what you need.
ScreenHunter 289.jpg

The other thought is that I've seen bushings for grinding wheels that are made of plastic. Peter suggested finding someone with a metal lathe who could make a bespoke bushing, but I wonder if you might be able to turn one on a wood lathe from a material like HDPE or Delriin. The challenge is that the wall thickness will be rather thin - a bit more than 1mm. IF it were thicker, I would suggest trying a very hard timber such as lignum vitae.
 

alpha1

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Mar 29, 2018
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middlesbrough
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Dave
Just get a piece of 15mm round bar stock and drill a 1/2" hole through it then cut it to length. I will have a look I might have a bit in the shed. What do the originals look like I might be able to machine you a set if you have a picture of what they look like. I can machine and cut a piece 15mm by 40mm long with a 1/2" hole through the centre if that would suffice.
 

alpha1

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Mar 29, 2018
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middlesbrough
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Dave
I turned down a piece of stainless tube to 15mm outside diameter and 1/2" bore there is not a lot of meat left on the tube its really really thin.
 

alpha1

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Mar 29, 2018
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middlesbrough
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Dave
Make one out of Brass bar.:thinks:

Why would I want to make one out of Brass I have made one out of stainless he just needs to pm me his address and I will stick it in the post. It's 15mm outside diameter and 1/2" inside diameter he just needs to cut it to lentgh.
 

Tiny James

Full Member
Joined
Oct 13, 2020
Posts
194
Location
Rugby
First Name
James
Thank you all for the advice

Alpha I have sent you a pm and thank you my friend please just let me know how much I owe you and provide me with your paypal email and I will send you payment

James
 

alpha1

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Mar 29, 2018
Posts
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Location
middlesbrough
First Name
Dave
Hi they are in the post.
I have made three at 15mm outside diameter.
One is 1/2" internal
One is 13mm internal.
The third one is a different piece of stainless with a 1/2" bore.
All three internal diameters were reamed to size so should be accurate. They are all 25mm long as requested. Let me know if there are any problems with them. :thumbs:
 
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