Norton surface grinder, $850, Newcastle, ON

[JustaDB]

Norton surface grinder | Other Business & Industrial | Oshawa / Durham Region | Kijiji Classifieds

Extremely nice finish Comes with chuck Variable speed with VFD Single phase Very heavy and robust Not Chinese junk $850 firm Can be tested

www.kijiji.ca

 

[YYCHM]

 

[Mcgyver]

That is one tall mag chuck. Don't like that, but the grinder is a great deal.

I've gone one and they are a well made high quality grinder. The table travels on rollers that run on harden strips so they are very smooth and the back and forth takes less effort. The surface that wears, the steel strip, is a replaceable wear part. Not sure where you'd find a replacement, but a brilliant idea nonetheless!

 

[JustaDB]

If that was a few thousand km closer, I'd be on it like a fat kid onna Smartie.

 

[JustaDB]

Don't like that...

Why not? What does it change?

 

[Mcgyver]

It wouldn't stop me from getting it, but the gripe is reduced daylight, i.e. maximum space between wheel and chuck limits the size of the set up/work piece. Most of the time it wouldn't matter, but when it did, its a problem.

As its more entertaining with some photo's, here are two examples. I ground some dovetails not to long ago and barely had enough room. Don't think I could have with that chuck, or at least not without removing the chuck and working from the table which is royal pita and possibly not as accurate as the top the chuck is ground in, so then you're messing about grinding the table ..... or instead buy one with a normal height chuck .






Second one is an assembly for my ultimate vise stop that used all the available room. The assembly is about 7" tall, the giant V block makes it look small

 

[Gennady]

I ground some dovetails not to long ago

Hi Mcgyver. What exactly are you grinding in this setup. It might be camera angle and perspective, but none of the angles is matching dovetails?

 

[Mcgyver]

Sure, to grind the angle on the dovetail, the horizontal surfaces are first scraped. A few photos showing the process

First scrape. (the work in these pics is not the same piece, just included to illustrate the process)







then reference off the scrape surfaces to grind the opposite parallel





then with the ground surface (perfectly parallel to the scraped surface) mounting, grind the dovetail with the side of the wheel.





Yeah, I know, never grind on the side of the wheel, I'd tell the high school class the same thing . If you are careful, it is fine, tool makers do it all the time. The key is to put some relief on the side so there is maybe a 1/4-1/2 ring that is doing the grinding. Stops it from burning. That and a full spark out. Without touch ting size chuck it gets all the angle perfectly the same. Usually you have to scrape these, but this slide rest was small enough I could fit it on the grinder ..... and those tiny surfaces would be miserable to scrape.

A diagram I did showing the general idea of the relief before grinding on the side of the wheel (not for this project obviously, the wheel isn't dressed at an angle).





The result a fit as good or better than factory new.

 

[Gennady]

Great. Thanks. Compound slide on my 100+ Hendey lathe is very worn. I was searching trough internet and found different methods of fixing that - from scraping, milling to lapping off each other. this one looks most __right__ one. The only problem - I don't have sine plate

 

[Mcgyver]

I've scraped many, this was the rare case when it was small enough to fit on the grinder.

PS. Please don't lap it, that is a hack approach. These are precision mating surfaces and the fit can only be improved by removing the material at the specific spot that needs, it not indiscriminate removal that creates more clearance (slop). Secondly, when there is an application for lapping, it's is done with a lap that is a cutting tool, never between two work piece as it will not create flatness and will embed material in one or both surfaces leading to rapid wear