Unusual Grinding Spindle, Friction Drive Perhaps?

[Peter S]

The usual story - I won a few items at an auction, but they came with other unrelated parts. In this case the closure of a fairly long-established tool sharpening company. They did everything from making cutters on their 2x CNC Anca grinders to making or sharpening any type of cutter/blade/saw you can imagine. Old T&C grinders, newer automatic saw sharpening machines, surface grinders etc. Piles of accessories, few of them with their machines .

This spindle is a mystery to me, but I reckon someone on PM will know what it is.

At first there seems to be no way of driving the spindle, so I am guessing the knurled wheel could be for a friction drive?

After removing the knurled wheel, I took off the 'cover' (surprisingly thick walled) which revealed a small 'flywheel' with 3 x brass or bronze segments. The segments are spring loaded into their seats. Another guess - they fly out at a certain speed and contact the cover, so preventing spindle overspeed. The inside of the cover shows that contact has occurred.

The spindle is bolted to a slotted plate which looks to be shop-made.

The whole thing is pretty small, the grinding wheel is about 70mm (2.75") diameter.

Any ideas?

 

[in2glamisgirl]

Brake wheel dresser?

 

[L Vanice]

Whats inside a Brake Dresser?

The ones used for truing a diamond wheel? Obviously something to limit speed, so is it just a shaft with a couple of bearings and some sort of adjustable friction brake?

www.practicalmachinist.com

They are still made. Note that they are meant to true a diamond or CBN grinding wheel after mounting it on a grinder in case the wheel has a little runout.

Precise Brake Wheel Dresser For Diamond & CBN Wheels

Offering a huge selection of industrial tool sales online. Find over 100,000 metalworking products, precision measuring tools, power tools & accessories.

www.penntoolco.com

Larry

 

[CarbideBob]

Yep. Brake dresser.
These are for truing and dressing CBN and Diamond wheels.
The later models had the knurled wheel outboard so you did not have to put your fingers inside to get it moving.
Braking speed is adjusted by the screws in the shoes.
Shoes and cup look to be in very good shape.
Bob

 

[Peter S]

Thanks very much all who replied!

That I would never have figured out. The last time I used a diamond wheel was in the 1980's to sharpen a carbide press tool...but after many years away from the trade I now have a surface grinder and cylindrical grinder at home, so may be looking at CBN one day.

I found a Norton video showing it's use for truing: