Shaper Scraping Help

[eeler1]

Pete, DO IT!! Be open to an opportunity when it presents itself. And be humble, Richard is indeed an old crab, but he knows more about machine rebuilding than you or I.

Ok, now my question.

We usually use leveling to set up a machine and bolt it down in place. I get the three points thing, relaxing the cast iron and taking out the twist. Where I get confused is that at some point you are going to bolt that machine down to a bench or table or stand or the floor, at which time it probably won't be on 3 points anymore. So if you scrape it in when it is resting on 3 points, isn't that geometry messed up when you set it in place? Or are you creating new datum points for leveling in the same plane as the 3 points?

 

[Richard King 2]

I found this maintenance manual just now. http://vintagemachinery.org/pubs/1617/3678.pdf

It says to support it on the leveling lugs on page 5. I am assuming it has 4 and above the 4 is a hole you use to pull it down evenly. So pulling it down with one will twist the base. The Cinc. Shaper we scraped in FL had 6 - and we used wedge levelers under the lugs. Jon, he could scrape it sitting on one lug tight and the base will no doubt be twisted, match fit the ram and scrape everything square with the lousy square. Then unbolt it and move it, then try to align it back in the 1 lug position. Impossible. So before scraping anything you align it on the floor like the manual tells you too so after it is moved you can get it back to the same position.

3 points is used in many machine bases with only 3 lugs and smaller perimeter lugs to keep the machine or surface plate from twisting. We use 3 points on other parts to keep them twist free when sitting under their own weight. You and everyone knows cast iron bends whenLeveling a lathe and aligning the bed is done all the time and we use leveling screws to twist (bend) the cast iron bed. The ram is a noodle,even though we figure it is cast iron and won't bend. You should have seen the eyes of Keith Rucker and John the shaper owner when we retested the ram after we set it on 3 points. They couldn't believe their eyes. I have been using 3 points as far as I can remember as it is an integral part of machine rebuilding. You must have been napping when I taught 3 points in the classes you took? That's why I say using 3 points is also a "lost Art"

 

[middle.road]

As in inspection and basic geometry, (3) points determine a plane.
Large surface plates are mounted on (3) points and if you look at images of cast iron plates there's usually (3) bosses on the bottom.

 

[eeler1]

I may have napped a bit, scraping wears us old guys out you know.

Thats a good reference on shaper setup and operation, thanks for posting that. You may see a shaper in Vacaville.

 

[Janderso]

And he is an avid camper

 

[Pete301]

I found this maintenance manual just now. http://vintagemachinery.org/pubs/1617/3678.pdf

It says to support it on the leveling lugs on page 5. I am assuming it has 4 and above the 4 is a hole you use to pull it down evenly. So pulling it down with one will twist the base. The Cinc. Shaper we scraped in FL had 6 - and we used wedge levelers under the lugs. Jon, he could scrape it sitting on one lug tight and the base will no doubt be twisted, match fit the ram and scrape everything square with the lousy square. Then unbolt it and move it, then try to align it back in the 1 lug position. Impossible. So before scraping anything you align it on the floor like the manual tells you too so after it is moved you can get it back to the same position.

3 points is used in many machine bases with only 3 lugs and smaller perimeter lugs to keep the machine or surface plate from twisting. We use 3 points on other parts to keep them twist free when sitting under their own weight. You and everyone knows cast iron bends whenLeveling a lathe and aligning the bed is done all the time and we use leveling screws to twist (bend) the cast iron bed. The ram is a noodle,even though we figure it is cast iron and won't bend. You should have seen the eyes of Keith Rucker and John the shaper owner when we retested the ram after we set it on 3 points. They couldn't believe their eyes. I have been using 3 points as far as I can remember as it is an integral part of machine rebuilding. You must have been napping when I taught 3 points in the classes you took? That's why I say using 3 points is also a "lost Art"

I found this maintenance manual just now. http://vintagemachinery.org/pubs/1617/3678.pdf

It says to support it on the leveling lugs on page 5. I am assuming it has 4 and above the 4 is a hole you use to pull it down evenly. So pulling it down with one will twist the base. The Cinc. Shaper we scraped in FL had 6 - and we used wedge levelers under the lugs. Jon, he could scrape it sitting on one lug tight and the base will no doubt be twisted, match fit the ram and scrape everything square with the lousy square. Then unbolt it and move it, then try to align it back in the 1 lug position. Impossible. So before scraping anything you align it on the floor like the manual tells you too so after it is moved you can get it back to the same position.

3 points is used in many machine bases with only 3 lugs and smaller perimeter lugs to keep the machine or surface plate from twisting. We use 3 points on other parts to keep them twist free when sitting under their own weight. You and everyone knows cast iron bends whenLeveling a lathe and aligning the bed is done all the time and we use leveling screws to twist (bend) the cast iron bed. The ram is a noodle,even though we figure it is cast iron and won't bend. You should have seen the eyes of Keith Rucker and John the shaper owner when we retested the ram after we set it on 3 points. They couldn't believe their eyes. I have been using 3 points as far as I can remember as it is an integral part of machine rebuilding. You must have been napping when I taught 3 points in the classes you took? That's why I say using 3 points is also a "lost Art"

Hi Richard.
Thank you for your very kind and very generous offer to attend the the Oswego class! My wife’s health keeps me close to home so I have to decline, but I’m so touched by your offer.

They say you learn by your mistakes so maybe I’ve learned a little about how not to do things!
I never even thought about how I had the base bolted down. I’ll have to bolt it down properly and recheck and probably re-scrape. The base bolts to the table in 3 spots so I’m beginning to see the 3 points concept in practice.
So I should use linen grade phenolic instead of Trucite on the column flat ways. Another major mistake avoided thanks to you.
About scraping the ram. Yeah, I just had it resting upside down on the work table while scraping, certainly not on 3 points. I’m studying your pics to learn how to duplicate that setup.

You asked about my surface plate so I included some photos. (Staged just to show what I used).

 

[eeler1]

Is that a Leonard grind-r-lap in the background of that last photo?

Family comes first, bummer that you can’t make the class. Even a day of observation would be beneficial, if that’s possible.

 

[Pete301]

Is that a Leonard grind-r-lap in the background of that last photo?

Family comes first, bummer that you can’t make the class. Even a day of observation would be beneficial, if that’s possible.

I think it’s the same thing but marked “Cold-Grind”. A EBay deal, but had to make the diamond discs.

 

[Janderso]

Pete301,
I’ve been working on my own diy slow speed diamond disc lapping machine for putting the 5 degrees on carbide for scraping.
The shot of the Cold Grind has the same mechanical pivot design I was creating on paper.
The pivot point needs to be at the disc face. When you try to do that, you need to have relief cuts in the table.
This design allows for that movement.
Great timing and validation of my get to lapping machine. Two thumbs up!

 

[Richard King 2]

Ahhhh now I see you have a granite plate, I assumed you had a small plate and straight-edge. Did I miss where you showed that?. Jeff and Jon, Bob, John York, Rex, Ultra...what would be an obvious questions my students should ask about how the granite plate is sitting?

They have to start thinking a bit deeper now that they have taken the classes. I would like this to be a learning curve here for everyone. Pete if you could blue up the ram from the plate it would help too.