Delta T & C Grinder

tertiaryjim

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Bought a Delta tool & cutter grinder 17 months ago.
Had been looking for something similar for a couple of years but on the few occasions something came up I was physically unable to investigate let alone load n haul one.
So this showed up on Craigs list only a 4 hour drive away. I live a hundred miles from any large town and it's a desert for machines here.
The motor vibrated like a out of balance washing machine. The chuck had been ground and the finish was really, really bad. The table travel moved fine, for a workout machine.......Gonna Pump You Up!
I tried to talk the guy down a bit but he knew few similar machines ever showed up and he would get his price.
So I told him I could scrape it in to which he looked horrified and told me I should leave it alone.
Can't leave something like this alone.
Replaced the motor but I didn't spend for a highly balanced one and some vibration still exists.
The finish was greatly improved.
Removed the chuck and after cleaning I measured it. End to end it was ok but in the 5.5" width it was out 0.002". This told me the wear was much worse than expected.
The top of the chuck will be ground in when everything else is done but I thought to blue the base.
IMG_0337-1.jpg This blue check was done with the blue smeared on the plate with a plastic butter knife. Worked on the base till it showed 95% contact. Scraping steel is no fun so I might leave it as is. Maybe.
The ways all had to be machined. What fun that was on my little mill-drill. Since they had to have a reasonably true surface to rest on while I machined the other side, I had to scrape the high points of one side till it could make a nice base.
Had to take off 4 to 12 thousanths from each surface.
IMG_0357-1.jpg After milling 6 thousanths off this surface and spending some hours roughing it in I still had some areas that scraping couldn't clean up. Two of the leading edges had these deep gouges which couldn't be there. Thought about milling the leading edge back a little but the scratches would still be there. Back to the mill and took the surface down another 0.006".
IMG_0322.JPG This shows the bottom of the casting and the ways that had the deep gouges.

The top side of the casting has a problem for which I need advice.
IMG_0366-1.jpg There were two places I drilled and pressed pins because of voids but after machining and scraping, this area looks much worse. Its about 3/8" X 1/2".
The ways are scraped on plane and parallel, Top & Bottom Ways, within two tenths. since this will be my master for scraping the base I thought I would rough in the base before finish scraping this casting in case I get some minor scratches.
Also, I don't have machine capacity to true up the guide that runs 19" of the casting width so I plan to make a hand plane that will run on the way and a few scratches n wear will result.
IMG_0176.JPG This shows the 19" long guide way which has at least 3 thousanths of wear. The cuts with a hand plane will be very small and should be easy to handle. Just a lot of passes. The main base also has a guide way that needs to be cleaned up so the plane will be used twice on this machine.
Now I'm starting to ramble so best get to my question.

Should I bore and inset a piece of cast iron into the bad spot or will the risk of warping it be too much to take? I could get some low temp solder but if the casting warps I might just cry.
 
Unless you are worried about it collecting crud, I would leave it alone. The least I would do is get some metal epoxy and fill it in and scrape it flat.

My dad had one of these we picked up many years ago with similar problems of wear. He put the pieces up on his big mill he had and mill the surfaces to get them straight and flat again. He did some scraping and fitting to get decent bearing between way surfaces. The old grinder is long gone. Probably got melted into Chinese dial calipers. Who knows. Ken
 
4gsr That sounds like a very good solution. Quick, easy, cheep. All my favorite things.
When I drilled to press the pins in a lot of nasty looking crud came out. It's clear the machine wasn't kept properly clean or lubricated
so that may have been 40 years worth of dirt but I would like to avoid it happening again.
 
4gsr That sounds like a very good solution. Quick, easy, cheep. All my favorite things.
When I drilled to press the pins in a lot of nasty looking crud came out. It's clear the machine wasn't kept properly clean or lubricated
so that may have been 40 years worth of dirt but I would like to avoid it happening again.
Agreed.
One problem with driving pins into cast iron, It can distort the slide and cause a bow. How much press fit? Loctite the pin in place, or make it a gentle tap in place. Better yet, maybe drill and tap a hole for a headless screw, filed flat. Again, loctite in place.
 
The brass pins are about 1/8" Dia and were a very light press. Just a few light taps with a 4oz ballpein to drive them in.
I was worried I had turned them too small and they would have to be enticed or drilled out to install larger pins but it was a perfect fit.
Wont move and too little stress to bother the casting.Since the brass is softer than the cast iron it should wear without
making much of a mark if it decided to move and they would have to move up.
 
Leave it alone! High spots get scraped away. Small low spots in a surface cause no problems, so leave them alone. Get a Sharpie and write "not mine" with an arrow pointing to the gouges... You are just going to cause more problems by messing with it. Make sure it is low and let it go...
 
Thats even better news.
I already have a sharpie.
Thanks Bob!
 
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