Better Gibs for mini lathe

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Sound great any photos

Dave
I don't mean to hijack this post, but here are some youtube links of video of the compound issues;


So the original assumption about the slide not running straight was wrong, it's a hollow ground into the top, as figured out later and spliced and shown in spliced in video.
 
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I still need to test the sine bar angle set against a test bar chucked into the spindle chuck. I have a zero set, and of Bison brand that has very small radial runout. If you own a cheap import lathe, buy a decent chuck for it.
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Ohhhh THAT "mini" lathe! No wonder I could not follow - I have a 7x16. You are in a totally different class of machine than I am!
 
I made some of leaded bronze bearing material came in a rod , for my 9x20 been in use for years now with no problems my originals looked like bad bananas and were always coming loose or to tight in spots and i had to resurface some of the slides as they had high low spots i scraped them in smooth as a baby's butt.
 
Ohhhh THAT "mini" lathe! No wonder I could not follow - I have a 7x16. You are in a totally different class of machine than I am!
I started with a 10x24 bench lathe (Jet brand) back in 1976. In 2004 I purchased a new 18x40, but it never was a catalog item at Grizzly. It was internet online purchase only, and I could afford it. I think they imported a half dozen of these. They probably got them for scrap iron price, as I can see every incorrectly made part was assembled into these. I wanted a lathe with a large bore hole. I fix broken stuff, and this lathe at least turns stuff true (with good chucks), but everything else is an issue. The tailstock point's off to the right of the spindle. And that don't appear to be fixable. When you watch a drill wobble as it finds center, and you know you just adjusted that with the 60 degree morse taper mounted centers, I scratched my head, and figured it was a long drill problem. Then I stuck a alignment bar in the tail stock, and swept it with an indicator to see it not parallel to the ways (about 0.012 in 10 inches). I used my bridge crane to lift the top off the tailstock, you can't correct that, as it's machined channels that controls that alignment. I got a real bargain with this..........
And you can see, I have to fix them as I find them.
This all started with the original head stock adapter, not fitting in the tapered hole of the spindle. The specifications for the lathe, say that the taper is #6 MT. But that is smaller then the 80mm hole through the head stock. So after posting on metal working sites, I found out it is a 90mm metric taper. This is common in Europe, as it is a DIN standard.
I measured it to be machined wrong, it seemed like it fit, but it would 'rock' in the headstock. So the adapter was hardened tool steel and needed to be ground with a tool post grinder. That lead to being able to adjust the compound to an accurate angle. And after having much difficulty getting it to the 20:1 angle (40:1 half angle) of the taper, the compound issue needed to be fixed.
I did get it (the adapter) reground last week. And I found the spindle bore to have issues as well, as the taper has a hollow in it's middle area (another scrap part saved!). Now the adapter fits very tight, and takes a bit of hammer force from a brass solid rod to remove.
 

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