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Proper way to repair scoring damage to this shaper ram

12teethperinch

Aluminum
Joined
Sep 6, 2009
Location
Edmonton Alberta Canada
Kind of a long title buy at least it’s not vague. I have a nice little south bend shaper that has suffered a lot of damage to the gib side dovetail of the ram. The shaper was missing the felt ram wipers so that may be where a chip entered. The good thing is the damage appears to be contained to the ram dovetail and the gib plate and the female part of the dovetail in the body of the shaper seems fine. My question is if I were going to try to have this repaired what would be the best way . The scoring appears to be no deeper than .020” would having it surface ground be the the way to go Would the cost be reasonable? Would a well machined surface give acceptable results. I don’t have the equipment or expertise to attempt this so it would be being done by “experts” if I can find them. I would just like a little prier knowledge on the subject before I go out and find someone to do the work. Thanks to any who reply for your Expertise. By the way it’s a small shaper and the ram is only around 24 inch long (that’s a guess since I am at work and didn’t measure). Will attach photos in the edit.
Darrell
 

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I'm thinking Moglice.

It doesn't seem worth rescraping/grinding the surface just for that damage, plus you might run out of travel on the gibs if you do that.
 
Personally...I would run an india stone over it to knock off burrs being mindful not to "dig" it all out...just keep it smooth, and do dress ragged edges too. I think there's still enough contact area there to keep it working properly.
 
Ugly but looks fine to me...

Yes it looks real ugly, but it looks like there is still untarnished surfaces above and below where the damage is so it shoul dbe fine for what it is.

If you want to make it better and given the forces involved are not too great, epoxy with grinder dust should do the trick.

Mix a batc of a good and strong epoxy, others here will have many suggestione, thin it with alcohol and mix in the grinder dust.

Have the damaged area flat so the epoxy can pool, then be sure it is very clean and apply the epoxy, after is is cured for a few days carefully scrape or file the epoxy down to the ram, then use a hand plane with very strong blade barely out to gently shave the epoxy and do not scraping the metal.

Next loosen repair any damage to the gibs and clean it all up.

Leave the gibs real loose and ink up all mating surfaces, then assemble and tune the fit, as the gibs get tight the ink will rub off the high spots, shave the high epoxy until it is finished.
 
Grinder dust? As in abrasive dust left on a grinder base? You can't be serious. Mixing this in the epoxy makes a first class cutting tool in this location. It's just going to wear the slide out in no time.

I'm not at all for epoxy in this application in any way, shape, or form (including moglice). This is not a lathe slide or a ding in a mill table, this is a shaper ram. It is going to see some serious surface speed, enough to probably melt the surface of the epoxy. If it gets gummed up with epoxy, it's going to start to gall again when the gummy epoxy gets hung up in the works and generates heat, just like it was melted plastic (which it will be after curing).

Matt has it, hone down the rough surface and let it run. Additionally I'd throw it on a plate and scrape as much as I could back level, leaning to the low side on the worst part of the galling. Just let it serve as oil reservoirs.
 
Grinder dust! Drugs seem to have funny side effects. :D

Either do it like Mike C. says.
Or make it perfect and let rework the ram and maybe make a new and thicker adjusting gib. Luckily, the score is on that side.

You could use Moglice (I have no doubts), but that would require deepening the scores to real pockets 2 mm deep. With the area affected, a very invasive repair. I'd prefer the more expensive regrinding.

Third option would be metal spraying, but that would require grinding/scraping too.


Nick
 
Looks to me to be on the border line for repair. You could give it a good stoning and then re-fit.
I've used " Moglice " to repair scores like this before but you need to make the scores deeper so the moglice has a decent key. I once came accross some filler made by " Devcon " in the US, it was a two pack style filler that was actually designed to fill in the space behind some cast ni-hard liners in cracker mill chambers. We had to buy a minimum order which was much more than we needed so some was left over. About a year later a had some scores to fill in an emergency and I used the " Devcon ", it was brillant.
I used it for years but eventually it ran out. When I tried to re-order guess what- " Devcon " no longer made it ! So that's when I got into " Moglice ", not as good as the " Devcon " in my opinion. Regards Tyrone.
 
I don't agree on the "epoxy will melt" idea.

I assume everyone here has heard of this material called "oil"..... it goes between surfaces and lubricates them so they don't gall and do what happened there. (Yes that had help from some swarf or other stuff that got in).

The mass of the iron , if nothing else, will keep it from getting that hot.

Anyhow, you NEED to fill it, OR grind past it. If not, swarf or other stuff will get in AGAIN, set in that "pocket" and do it again.

Epoxy should work fine.... Devcon was great..... is it really gone? that stinks. Haven't used any for years, but it worked great.

You could, I suppose, machine it down and make a thicker gib. That would solve all problems, if it isn't too stupid as far as depth.... a shaper ram gets some up-force, and too thick a gib will tend to jam.

I think epoxy or similar will work fine. I don't "buy" the heating issue.
 
I assume that in use the scorred portion extends past the gib when the ram is fully extended. If not- I would do as oters have suggested and stone it down and use it.

If it does extend past the gib when in use it is going to wear faster. This is due to to the decrease in surface ares to bear the load.

One option not mentioned so far is to drill a series of threaded holes and locktite in some cast iron plugs. The plug head is countersunk so the threads are buried. If you put in enough plugs and overlapped them you cound fill in all the major scoring. The heads are then filed and scraped down to be flush with the surface.

The above would be a lot of work. I am not saying it "should" be done- but wanted to point out that it could be done.

Personally I would be tempted to do SOMETHING to fill the portion of the score which would extend past the ram wiper. The wiper is not going to be able to keep another chip out if it happens to land in the scored portion.
 
Thanks for the replys so far. Why given the shallow depth of the score wouldnt machining or grinding be good, there is plenty of meat and gib adjustment. Is it because staying parralell to the other side would be tricky?
As you can see in the photo I have another southbend shaper so I am thinking of selling this one but with that damage to the ram even if the shaper is useable and given the rarity of these things here I will have trouble breaking even. I have to think even if the grinding was done and was a thou or two off it could be tuned out on the macihine. If I had a shop do it and they gave a lick to the other side of the ram at the same time wouldnt that tale care of the parralell issue? There are a few companys here in town that say they do machine rebuilding, I measured the ram last night and its onlt 18 inches long so I would think even if there machines were not top notch they would be able to hit the tolerence. Thanks for your imput.
Darrell
 
Are you saying you want to clean it up before selling, because the scratches will detract from the value?

There's no doubt the scratches lower value, but the cost of repairing it might be as much as the value added to the machine. In my neck of the woods, I doubt you could get that precision ground for under $400-500.
 
If you are going to do one side- you should do the other- and this means machining and scraping both ram and base side of the dovetail ways on the other side also.

It is the non gib ways that guide the path of the ram and establish alignment. That side is going to be worn also, and needs to be made true before you can make the scored side parallel to it...

If the other side has minimal wear you may be able to do just the scored side. Determining this will take some carful examination and measuring, as you cannot tell just by looking.
 
If you have it machined or ground, that is only part of the work. After machining or grinding, it must be scraped to flatness and within a few tenths of parallel relative to the other side. If the ram slides are even a couple of thousandths out of parallel, the ram is going to bind unless left that loose, which will allow it to wallow around at long stroke settings and adversely affect accuracy (equivalent of a loose spindle bearing on a lathe). If you have no scraping and machine tool restoration, this is not the place to learn.

On the epoxies... yes, oil SHOULD keep the ram from galling, but it didn't work with cast iron (apparently). If the epoxy gets hot, it's going to make a mess. On a mill or lathe way, this is never going to happen, as the movement is very, very slow. On a shaper ram at fairly long stroke and high stroke speed, you are looking at surface speeds of 60-70ft/min or more. The ways of this ram are a linear plain bearing. Would you recommend someone with a SB9 lathe that has a galled spindle to just fill with epoxy, slick it down and slap it back together? That is exactly what you are proposing.
 
It does not HAVE to be scraped. It's possible to get it ground within necessary tolerance, same as lathe beds are ground. It's not cheap however (per my prior post)

Some smaller, less expensive machines were not scraped originally. This SB might have be one such machine. My Atlas shaper was not scraped.
 
If you can grind each side concurrently, it does not have to be scraped. If you can't do them at the same time, in the same setup, chances are that you will not be able to hold the tolerance required on the dovetail. That's how they are done at a factory. A flat surface would be much easier to grind than the dovetails.

Also, as you note, it depends on how fine the tolerance. To paraphrase Smokey Yunick... presicion costs money, how precise do you want it? I'd suspect it costs more to get it ground within .0005 parallel over 18" than the cost of an Atlas shaper with a good ram and gib. Grinding the ram without making a new gib is pointless.
 
I have a 20 inch cincinatti with bad scoring on the ram I stoned down the rough stuff and got out the old chips that caused the problem and left it. I use the machine daily for production it works great. You have a tiny south bend shaper that you or the future owner will use on occasion for fun, I would not mess with it just clean it up and use it. I used to agonize over this kind of stuff when I was a tool collector but now that I am a tool user, if it doesnt effect its ability to function I dont care. All that matters to me is if it is reasonably accurate and not totally noisy and thrashed.
 
From looking at the pictures of the scorring, and considering the machine and it's likely light use, I think I'd try this....

There is a metal backed teflon type material that was used in early NC machines that had scrapped ways. This was a total of maybe .030 to .040 thick and was fastened to the machines bed in one of two ways... a double sided tape or a thin glue. I do not remember the manufacturers name, but it was phoneticly called DuMetal... It amounted to a bronze strip coated with teflon... I'd stick a strip of that on the ram, and make a new gib from cast iron or bronze.

What do the rest of the ways look like?
 








 
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