Surface Grinder questions

Sean Yaw

Gold Member
Joined
Feb 26, 2019
Messages
417
I am finally getting around to cleaning up a Harig 612 I picked up a couple years ago. I’m trying to keep a close eye out for red flags to avoid sinking a ton of time into a lost cause. I pulled the table off and was wondering if the ways on the top of the longitudinal carrier look normal. They are scraped to hell, but the pattern seems very strange for normal wear, so it makes me wonder if they are actually supposed to look like that. They don’t look like the pictures I’ve seen of hand-scraped ways. Any insights you have to either get me to bail or give me peace of mind would be appreciated.
IMG_5190.jpegIMG_5191.jpeg
 
Your grinder has been taken apart before , Maby for cleaning and the X marks were cut in, to add more oil flow i have seen this alot on older machines. im sorry im new here .and your pictures was something im familiar with and i replied.
 
Welcome Timberjack,
Good advice and information from personal knowledge are always welcome here from any member,

Fill out your profile so we know where you live and a bit about you.
 
Your grinder has been taken apart before , Maby for cleaning and the X marks were cut in, to add more oil flow i have seen this alot on older machines. im sorry im new here .and your pictures was something im familiar with and i replied.
Thanks a lot for the reply. Do you think that this machine should still be able to function reasonably with this modification?
 
My father would always say
..."We're not making watches".
 
Correct, someone (amateurishly) put oil retention marks (er… scars on that one) on it. There’s no apparent scraping evident. A negative is there appears to be scoring running horizontally on a short section laterally to indicate possible heavy use in the middle area, which is common. You won’t know if it’s “good” until you set it up and properly set your chuck on it and indicate, and then truly put in the time to learn the nuance of wheels—coolant-technique-grinding. But it’s pleasurable. What is “good” is up to you. “Function reasonably” - for? I understand knife making but ideally/theoretically w a hard used surface grinder, strive for .0001” or thereabouts across your chosen ground piece on such used machinery.

Apology if you already know, most manual grinders are a pandora-ish box of indications needed and proper chuck setup (and skimmed flat and to your machine) to ensure it’s optimal. You can chase your tail around trying to get it right unless you really lean into the basics and then some should it not run “very flat” from the get-go. And getting a great grind finish is a whole other topic.

When you lay it back on and put it together and properly tighten your magnetic chuck on it (one nut torqued other looser but tightened), start testing the travel w a proper quality one-ten-thou or .0005” indicator. Years ago when I bought my dirty used ‘50’s manual Butterfly/Sanford type, it ran .013” across! Nuts! (I didn’t test-indicate it in the back of a dark dirty home when I took the chance to buy it, not that it mattered since it could take about an hour or two to set one up properly to best determine its capability.)

Took me six months of odd weekends w a proper large granite for scraping and bluing to hand-scrape it to produce .0003” variance across about 12”, which was just about “good enough” for my use. There is a lot to setup and technique to get good flatness - another wonderful skill set. Read all you can about these grinders and hand scraping if you need to, and how to refine that to best your machine ways and travel. Good luck!!
 
Last edited:
Back
Top