Chinese 7x12" lathe, tailstock centers 1/8" above head stock center.

wahooo

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I know I have to level, check the ways, etc, but I got a new tailstock, same issue. So I gather that I have to mill down the base plate of the tailstock, to include deepening the V groove. I have no mill and the local shop wants a crazy $150to so this. I can probably get it done in a day with my height gauge, calipers, surface-block, angle griner, Dremel grinder, layout blue and files, I"m looking for an electric scraper for the ways and for finishing this base plate. Any other ideas and can I get such a scraper for sub $100? Source? Thanks, guys.
 
I know I have to level, check the ways, etc, but I got a new tailstock, same issue. So I gather that I have to mill down the base plate of the tailstock, to include deepening the V groove. I have no mill and the local shop wants a crazy $150to so this. I can probably get it done in a day with my height gauge, calipers, surface-block, angle griner, Dremel grinder, layout blue and files, I"m looking for an electric scraper for the ways and for finishing this base plate. Any other ideas and can I get such a scraper for sub $100? Source? Thanks, guys.
Power scraper will run out $1000-1500+ and require a lot of practice to do a good job. Also taking that much off by scraping would be insane. Does the lathe have a warranty? If you want a hand scraper, a Sandvik scraper runs about $85 on MSC with (1) carbide scraper blade. As a reference from a newbie, my first scraping job was leveling a 4" mill vise with 0.005" out of flatness. Took me probably 40 hours of work - for 5 thou!

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Honestly if the shop will do a decent job (especially if they'd grind it after milling), $150 is a steal. If the tailstock is split to allow lateral adjustment, it would be a lot easier to take material off of there. I wouldn't touch the V ways on the tailstock bottom unless there was no other way.

But #1, I'd be after the manufacturer to replace a defective component
 
yeah, but i screwed up and got it bargain basement on E bay. I ve been on other forums that indicate that even if you DO pay almost twice as much for the Grizzly, there's still massive issues. I 've got a couple of one-off issues and then I'll sell the lathe. It makes me sick how effed up it is. I had one of their millls and after I set the gibs, it was fine! GD them. Thanks for your reply. I'll have to do it with the grinders, file and layout blue.
 
Is there enough grip length on the headstock mount bolts to allow you to pad up the headstock?

Maybe use some old parallel bars?

TomKro
 
yeah, but i screwed up and got it bargain basement on E bay. I ve been on other forums that indicate that even if you DO pay almost twice as much for the Grizzly, there's still massive issues. I 've got a couple of one-off issues and then I'll sell the lathe. It makes me sick how effed up it is. I had one of their millls and after I set the gibs, it was fine! GD them. Thanks for your reply. I'll have to do it with the grinders, file and layout blue.
Yeah, you get a mixed bag of issues. The larger machines tend to be better quality, but the problems (where there are problems) are usually more involved to solve.

Sorry to hear about the lathe. Do share how you get it fixed up.

Also, use hi-spot blue NOT layout blue if you are going to be scraping. Hi-spot transfers between parts, layout does not.
 
Having similar issues on the mini-lathe, (higher tailstock), make sure you measure as many things as possible before altering your tailstock. I found that the top surface of the bottom casting was strangely machined. I measured 4 zones of the casting and found 4 different heights. It's tough to figure out your reference surfaces. Nothing on my tailstock seemed to be square. You are trying to align (or keep in alignment) many things. Vertical alignment, pitch, and yaw of the ram taper. I'm sure it can be done, although I haven't yet figured it out.

Before I do anything though, I'm going to completely disassemble my tailstock, clean and inspect it. No point of going through machining to correct errors, if something simple is awry.
 
i've had TWO tailstocks, same issue, and one of them is one piece, no removable baseplate. I"ve been told that shimming up the headstock can cause massive problems, too.
 
A one piece tailstock? Can't adjust the horizontal offset then. A mini-lathe tailstock is typically 2 pieces. The base, and main casting. The base has the pyramidal section and the flat that rides on the ways. The base also has a key. The main casting can adjust horizontally along the keyway. Typically there is a lock screw underneath. I modified mine so the locking screw comes in from the top.
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Shimming the headstock could work, but is less forgiving than working on the tailstock. If the headstock is not aligned, your lathe won't work well, you will cut a taper when you don't want to. Having a misaligned tailstock doesn't change how the lathe cuts UNLESS you are using a dead or live center. Then the misalignment will cause taper. You will have a terrible time drilling from the tailstock as well.

What makes it tough is the tailstock isn't really true anywhere. On the picture on the right, you can see 2 numbers, 31.6 and 23. That's the height difference in thousandths from the back left corner. If I recall correctly, the back right corner was 10. So you need to measure stuff and take some off in the right places. One good thing is if you go too far, height-wise, you can always shim it back. The other good thing is the tailstock castings are not hugely expensive if you screw it up. All I can suggest is to take a little off at a time and reassemble and see what happened and make your next move.
 
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For 86 bucks, I would skip all the irritation, and buy this instead. In doing so, you upgrade to cam-lock for the tailstock too!
You should confirm your headstock is at the right height, and not aiming downward. Put a rod in it, and see if the distance between the ways and the rod remains consistent the full length.

 
I would have called my credit card company and gotten my money back- no way you should need to fix stuff like that
Don't buy imported junk without a company behind you (like Grizzly or PM)
-Mark
 
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