Hi Question about Buffing Machines

[saitou]

Hi guys!
I've been looking at bench grinders on ebay

BRAND NEW 200MM BENCH GRINDER WITH WORK LIGHT. ONE HP MOTOR $89.00 CHEAP POST | eBay

could something like this be used with the polishing wheel's that I see in the pictures of gssixgun's workshop or the restoration video's on youtube?


If anyone from melb/aus knows of a decent brand of this kind of thing that could be used for this purpose that is not too expensive please let me know =].

Thanks


-John

[mainaman]

You need to consider several factors when buying grinder/buffer.
RPM/ HP and also if it can be modified.
The one you show has more then enough HP, 1/4 HP is the minimum useful fro buffing. The RPM is also acceptable although it may be a bit high, what really matters is the surface speed of the spinning wheel, and that is a product of the radius and the RPM. The higher the easier to overheat the blade. Lastly you need to be able to add shaft extenders to the grinder to make it more useful for razors. Right now the way it is it does not have enough clearance to buff a razor without hitting the housing.

[Mikael]

It's a little to high rpm for my taste, around 1800 should be better (so the heat temper in the steel dosen't get compromised.

Edited: man, I write too slow. Cheers Mainaman!

[saitou]

How about a 1/3 hp with 6'' wheels 2950rpm??

http://www.ebay.com.au/itm/NEW-MODEL...75922089250831 is this one good?

[mainaman]

all you need to know
How To Buff And Polish - Caswell Inc

[saitou]

thanks mainaman =] that's given me a lot more insight. I realise I don't really need a buffer at this stage. But I just like looking at stuff I might want to buy one day hehehe. When I get sick of hand sanding i'll know exactly what to get.

[skipnord]

This would work ok with a set of extensions and 4 inch wheels.

[jamesm]

This may have been answered elsewhere on SRP but i'd like to reask: Can one hook up a bench grinder through a variac to lower the speed? I have a 1/3 HP grinder that i have removed the guards from to use primarily as a buffer. Right now there are two 6" spiral buffs, and I have some 8" (variety pack from eastwoods) coming, but I feel that heat has been a little of a problem and I would like to knock it down a notch. I do not have arbor extensions yet, but am planning on investing in a few.

The grinder is a 1/3 HP Craftsman, 2750 RPM.

[Geezer]

This may have been answered elsewhere on SRP but i'd like to reask: Can one hook up a bench grinder through a variac to lower the speed? I have a 1/3 HP grinder that i have removed the guards from to use primarily as a buffer. Right now there are two 6" spiral buffs, and I have some 8" (variety pack from eastwoods) coming, but I feel that heat has been a little of a problem and I would like to knock it down a notch. I do not have arbor extensions yet, but am planning on investing in a few.
The grinder is a 1/3 HP Craftsman, 2750 RPM.

The simple answer is no. Yes the grinder will slow with load. It will lack power and the motor will heat quickly. The rotational speed is controlled by the current cycles and the way the motor is wound and internally connected.
A variac will work with a bridge rectifier and a DC / universal motor.
Hope that can help you.
~Richard

[jamesm]

Thanks, Geezer. I will just have to be mindful of the heat.