Thread: Power for a toolpost grinder

Originally Posted by nearnexus

If you use the angle grinder to drive a precision spindle, you will get a precision job. It's that simple. I would never using a basic angle grinder as a TPG.

Ah, OK, I missed that bit. I can see that working as the angle grinder is just providing the motive power.

I've got a broken Mactec if anyone wants some parts. The diecast gear housing is broken when I - err - did something stupid so it really is only good for parts. Wasn't running at the time so the gears should be good. I simply haven't got around to sending it to the scrap bin yet but that's where it's going to go.

PDW

Originally Posted by Techo1

Grinding to a tenth or less in a lathe using a toolpost grinder is a bit of a "hit or miss" situation. Roundness and taper is difficult to control even with the best equipment. Achieving a true .0001" tolerance on a precision cylindrical grinder doesn't just happen it requires extreme operator skill and care.

I totally agree with you, I was just pointing out the need for good bearings if your wanting good results for grinding bearing fits etc.
I have done plenty of bearing fits with HSS in the lathe, and like you say it doesn't just happen., but can be done.

Just the other day I needed to machine the rear of the lathe saddle in the mill as it was not true enough to fit the taper attachment. I got it to within 2 tenths of a thou over a distance of around 250mm, but I was only worried about 190mm of it where the taper attachment mates to which is only out around 0.00015 tenths. Once I got it to there I called it good enough for this job.

I had to take a clean up pass to get rid of the rough milled surface so I could use the dial indicator accurately, and it did take some measuring and setting up but I got it there.

The taper attachment needs machining yet so I will see how that comes up as it may end up a tenth or 2 the opposite way which will make it line up spot on.
I don't think the factories would go to this trouble, but I am only a home shop and have all the time in the world at no cost.
Chasing tenths is no fun at all.


Sorry for using the imperial/metric, it's just I have a few nice tenth indicators I use for jobs like this. For those that need a conversion 1 tenth of a thou is 0.00254

Dave

Originally Posted by nearnexus

The Waldown runs a flat fibre belt and tension is very low.

Rob, where do you get the belts?

Originally Posted by eskimo

Rob, where do you get the belts?

My mid 70's Waldown C01 came with two new belts.

These are an old style white fibre type, and after years of use the one on the TPG is black and getting pretty fayed, so it may fail soon. Still one to go. So I haven't actually had to source any.

My understanding is that CBC Bearings sell a thin and light rubber compound flat belt to fit these. Failing that Brobo Waldown Australia would have them in their spares section.

Brobo Group - Cutting Saws, Machine Vices, Precision Drilling Machines, Pedestal Grinders

Cheers

Rob

I got a new (flat) feed belt made up for my lathe by Rydell belting in Dry Creek (although they are nation wide).
They may be worth talking to.

Michael

Originally Posted by Michael G

I got a new (flat) feed belt made up for my lathe by Rydell belting in Dry Creek (although they are nation wide).
They may be worth talking to.

Michael

I'm going to have to get a flat belt for my Schaublin 102 soon. What are their prices like Michael?

How do they join them ? What are they made of ?

Any information on this subject much appreciated.

Cheers

Rob

I can't say much about it really - the belt required is 1" by 32", 3/32" thick and one I purchased is (synthetic) fabric based with a grabby liner. Very non stretch and it's still going strong today. From memory (this was 3/ 4 years back) it was around $70. A bit on the expensive side, but as I'd been trying to get a UK guy to supply for the last year and his prices were higher still I figured it was that or nothing. It looks like the joint is a heat based thing although it could be glued.
I live out Norwood way, so if you wanted to see it in the flesh that might answer some of the questions you have, perhaps send me a PM.

Michael

Originally Posted by nearnexus

My mid 70's Waldown C01 came with two new belts.

These are an old style white fibre type, and after years of use the one on the TPG is black and getting pretty fayed, so it may fail soon. Still one to go. So I haven't actually had to source any.

My understanding is that CBC Bearings sell a thin and light rubber compound flat belt to fit these. Failing that Brobo Waldown Australia would have them in their spares section.

Brobo Group - Cutting Saws, Machine Vices, Precision Drilling Machines, Pedestal Grinders

Cheers

Rob

Brobo want my arm and leg....but I might have too?

Originally Posted by eskimo

Brobo want my arm and leg....but I might have too?

Did you try CBC ?

Rob

Originally Posted by Michael G

I can't say much about it really - the belt required is 1" by 32", 3/32" thick
Michael

That sounds very close to what I want.

I suppose the price is reasonable when you compare it to serpentine belts etc (which are well over $100 in most cases).

I will try that place, and I might also give Redwood Machinery a call as they may be able to steer me towards someone.

Thanks

Rob