Hi fellas, Hope every one is doing well.
I need some advise on a surface grinder I bought recently, the spindle seems ok , no noise or slop, but the saddle shows excessive wear. If you put an indicator on the table (with the chuck removed), pushing the saddle away from you, the indicator will drop off .002 in the first 1/2 " of travel then at about 1-1/2" it will gain .004". this is the worst spot that I have detected but it will gradually gain another .004" or so as you traverse the rest of the way across the table.
I ground a part 2"x 4" on the better part of the table ,it was tapered .001' across it's width and .002" over it's length. When grinding another part over the "bad spot" it was observed that the cut got lighter at first then stated to get heavier as the the saddle lifted the part into the wheel.
I wonder if it would pay me to disassemble and take the base and saddle to a grinding shop and have them surfaced? the table ways are removable and ride on ball bearings, I'd like to have them ground also. Any advise on this matter would be appreciated.If anyone can recommend a grinding shop in central PA that is up for this job that would also help.
oscer
Badly worn saddle ways on Chevalier surface grinder
Badly worn saddle ways on Chevalier surface grinder
"...that they are endowed by their creator with certain unalienable rights,that among these are life,liberty and the pursuit of happiness." Thomas Jefferson
"When the people find that they can vote themselves money, that will herald the end of the republic." Ben Franklin
"When the people find that they can vote themselves money, that will herald the end of the republic." Ben Franklin
Re: Badly worn saddle ways on Chevalier surface grinder
Anything I can offer is going to be of limited value since I've never been into one of the Chevalier grinders and don't know how the internals are designed. If the ways are worn that much then I'd bet the balls are as well. Are new sets available? Best advise I can offer is repeating what the Conelly books says. You have to do a proper survey of the machine, get some measurements of what's worn and how much, then you can decide what and how much needs to be done. Without getting into the head and bearings a surface grinder shouldn't be too hard. Pull the table and use the straightest straight edge you have and a good light on the ways and with that wear it should show up well. Since the Y axis gets a lot less use it may/may not be ok. But I'd check to be sure. That should give you a rough idea of how worn the machine is at least for the table area. If you've got better straight edges, large surface table, really accurate machinist's level, kingway tool, etc, etc then you can get some accurate numbers. A good level should show if the ways have any twist as well.Check the rack, cable drive, or whatever system it uses to cycle the table back and forth. If it's a hydraulic machine then that's way outside anything I know about.The mechanical drive types can get a lot of wear. Any lip seals if it's got them that keep the grinding dust out probably need replacing as well. Chevalier's are supposed to be fairly good machines so depending on the model parts might be easy to get. No idea about how proud they might be of them and where they like to gouge the customers though. If you do decide to get it reground. Pretty much all the threads I've read about rebuild shops that have the experience to do so say that the ones worth going to charge accordingly. So shopping by price alone usually isn't a good idea. I'd be checking for shops that do mention they do machine tool rebuilding and not just the ones who have large surface grinders for job shop type work. But with removable type ways that usually means there designed to be replaced and not reground.
Even if you have zero plans to get into rescraping it there's a few YouTube videos up about rebuilding SG's that might be well worth the time. This Old Tony has some that are well done from a home shop guys perspective. Pierre's Garage shows a few about replacing the balls and new cable drive. Depending on how much you know about using a surface grinder Shadon HKW and Oxtoolco have some good ones about getting decent results and a bit about what wheels there using. I've learned a great deal from them and have also learned there's way more to it than I'd thought. I'd bet Harold has more than a few ideas about wheel selection as well.
Even if you have zero plans to get into rescraping it there's a few YouTube videos up about rebuilding SG's that might be well worth the time. This Old Tony has some that are well done from a home shop guys perspective. Pierre's Garage shows a few about replacing the balls and new cable drive. Depending on how much you know about using a surface grinder Shadon HKW and Oxtoolco have some good ones about getting decent results and a bit about what wheels there using. I've learned a great deal from them and have also learned there's way more to it than I'd thought. I'd bet Harold has more than a few ideas about wheel selection as well.
Re: Badly worn saddle ways on Chevalier surface grinder
When I bought my grinder I read an article that had a few ways of mitigating some of the wear in the ways by regrinding the table .
I'll see if I can find it again , none of the methods was a "fix" for the worn ways .
But would return some use to a worn out machine
I'll see if I can find it again , none of the methods was a "fix" for the worn ways .
But would return some use to a worn out machine