CBM Wheel is this a stupid idea ?

[ps.harris80]

Hi all

This is probably a stupid idea so please do tell me so if it is.

So I would like to use a CBM wheel to sharpen my turning gouges, but I have a problem, 1st I don't own a bench grinder and 2nd CBM wheels work best on a slow speed grinder and they are not as common.

So I started thinking about this and had a bright idea, what about fitting an arbour to the wheel and fitting it in the chuck on my lathe, that is variable speed going down to about 500rpm is much more solid than a bench grinder and it offers a solid base to attach any grinding jig I de idea to use.

Is this a stupid idea or world it work.

Thanks for humouring me on this one.

Paul

 

[Against_The_Grain]

First, get a bench grinder with regular aluminium oxide wheels on, and then after using it for a while assess whether the cost of a CBN wheel is actually justifiable for what you're doing over just using the aluminium oxide wheels which work perfectly fine on high speed steel.

 

[Orraloon]

In theory mounting a CBN wheel on the lathe would work but it would be a pain in the @#$3 as you would have to take the work off the lathe every time you sharpen. You would spend as much time putting things on and off the lathe as you would turning. As said above get a basic bench grinder with an alox wheel. They work just fine.
Regards
John

 

[Lefley]

Hi all

This is probably a stupid idea so please do tell me so if it is.

So I would like to use a CBM wheel to sharpen my turning gouges, but I have a problem, 1st I don't own a bench grinder and 2nd CBM wheels work best on a slow speed grinder and they are not as common.

So I started thinking about this and had a bright idea, what about fitting an arbour to the wheel and fitting it in the chuck on my lathe, that is variable speed going down to about 500rpm is much more solid than a bench grinder and it offers a solid base to attach any grinding jig I de idea to use.

Is this a stupid idea or world it work.

Thanks for humouring me on this one.

Paul

It's a brilliant idea. If it's all you got it so will work!

 

[Jorny]

Sparks and wood dust/ shavings is not a good combination.

 

[Sideways]

8" CBN wheels work absolutely fine on a 2800 rpm grinder. Industrially, electroplated CBN wheels are run at surface speeds 40% higher than that. I wouldn't get hung up on the slow speed idea.
Wheels using CBN electroplated onto solid steel are very heavy and need to be very precisely balanced. They are not the only type of CBN available but they have been the ones promoted in the west for sharpening turning tools. On an arbor, in and out of a wood lathe chuck, those wouldn't be precise enough for me. Your mileage may vary ....
Find a good size bench grinder and don't worry about it. Just make sure the grinder spindles are long enough to take the width of the wheel and the wide flanges that are common with wheels supplied in the UK
As pointed out on a very recent thread about this, there are other CBN wheels available with resin or plastic hubs and just a thin metal rim to carry the abrasive. These are far lighter, cheaper and often don't use bushes to adapt the bore to the spindle.

 

[Phill05]

Paul not a stupid idea,

A few months ago I came across a post on another forum that gave me the inspiration of another tool I was missing a slow rpm diamond grinding/honing plate, I had been looking online at different machines for doing it, but mostly based on a std grinder in my past experience that was way too fast, What I gleaned from that post this was what I needed to add to my indexer as I could have it running at low speed.

So this is where I started the honing plate, I fitted a series of magnets to a 150 mm disk to hold the diamond plates and made a 20mm back plate to fit into the ER32 collet.

(20mm fitting, Mags fitted)



I have a 1000 grit disk that I dropped on and it worked well is great at sharpening tools and shaping & polishing small parts and gem stones but sometimes a little too much pressure made it slip, I was telling a friend about it and was given two diamond disks 400 grit and a 1500 grit to try but both had different mounting holes, so I made a reversible centre plate that has different sized spigots and drilled two locating studs so stops any movement, this is now done and it should work really well.

(Top original used disk and new disks) (New disk fitted)



(Fitted to Indexer and working)



If you wanted to fit and use on a lathe then a different type of clamping of disk to back plate would be needed.as it would throw it off and slice some body parts off.

 

[Phil Pascoe]

Just watch FB Marketplace for a decent grinder - there's an 8" record near me for £70, I picked up a W. German made 8" one for £20.

 

[ps.harris80]

Thanks for all the relies.

I ended up getting a bench grinder and seem to be managing just fine with the fitted 8 inch ally oxide wheels, so may give CBM a miss for now and see how the wheels lasts, as I can get 5 ally oxide wheels for the cost of one cbm.