9X20 Chuck

[stioc]

If your lathe can't take more than 0.020" deep cuts in aluminum then you need a better tool, not a bigger lathe. My opinion, anyway.

You may be right @mikey , it feels like the tools rub if I try to go with heavier cuts. The AXA toolpost I got from LMS extends the original center stud using a hollow shaft that's threaded internally and externally on the two ends. I think that hollow shaft causes some of the flex.

I'll try to find some garage time soon and give the little 9x20 a good tune up and see what can be improved.

 

[mikey]

Hmm, maybe make a new stud? Your lathe is definitely capable of far more than you're getting. It is patterned after the Emco Compact 8 and I personally know that lathe can easily take a 0.070" deep cut in aluminum on the radius (0.140" reduction on the diameter) with the right tool. My Sherline lathe will take the same cut in aluminum and will take 0.050" cuts in mild steel. Your lathe should be able to do much better than my Sherline, right?

I am referring to HSS tools, of course, and I suspect that your lathe will perform much better with HSS tools vs carbide. You might consider switching tooling and see how that works for you.

 

[hman]

hman, yep that's the 7" 4 jaw I have too, and I agree it's a cheapo chuck. What brand of 3 and 4 jaw chucks did you get? were they a direct fit on the 9x20's spindle?

Also what lathe did you upgrade to and why? I ask because I've been thinking about getting a 12x at some point in the future. Not necessarily because of the work envelope but for rigidity so I can take heavier cuts than .010-.020" (aluminum with carbide insert cutters) at a time. If the bits aren't super sharp the stock tends to gal and/or jump out of the chuck with heavier cuts.

I bought both of the larger chucks from Enco back in 2014. The chucks had "plain" backs. Bought backplates from LMS and machined them to fit the chucks.

I used to divide my time between Oregon and Arizona, had machines in both shops. A Grizzly 12x14 lathe in Oregon and the Grizzly 9x20 in Tempe, AZ. We sold both houses late in 2017/early 2018 and combined into a new house and shop in Chandler, AZ. I decided I didn't need both lathes, so I sold the 9x20.

 

[C-Bag]

Hmm, maybe make a new stud? Your lathe is definitely capable of far more than you're getting. It is patterned after the Emco Compact 8 and I personally know that lathe can easily take a 0.070" deep cut in aluminum on the radius (0.140" reduction on the diameter) with the right tool. My Sherline lathe will take the same cut in aluminum and will take 0.050" cuts in mild steel. Your lathe should be able to do much better than my Sherline, right?

I am referring to HSS tools, of course, and I suspect that your lathe will perform much better with HSS tools vs carbide. You might consider switching tooling and see how that works for you.

There are just so many details to the 9x20 it's hard to come up with hard and fast rules as I think because of the lack of QC they can have different problems. Mine was bought used by a guy who liked the idea of the machine being a hobby in and of itself. There was a lot of stuff with the machine one being a big binder of the different websites on the 9x20 and all the different mod's. It's thick!

So one of the many things I chased was chatter when trying to take a decent cut in steel. The first thing I got from LMS was the heavy duty 4 bolt compound mount. That helped. Part of it was the sloppy way the compound was. It was not machined even close so it was really hard to get it where the dovetails were not floppy no matter how tight I got the gibs. I did a minor scraping on it and it was much better.

But I started noticing chatter again and it turned out that pivot bolt for the QCTP (which was solid, I guess he made) didn't want to really tighten good. I realized the pivot bolt under pressure pulled up on the top of the compound causing it to "dome" up under the middle of the QCTP making it not sit flat on the top of the compound. Took the QCTP off and machined a relief of about .020" off the bottom around the hole for the pivot bolt so the QCTP now sat flat on the compound.

So with each tweek it got better and better being able to take .060"+ cuts in steel no problem once I got the right configuration HHS tool bits. Then I tried to do a part which had gotten to be no big deal finally until this one. I just bulled ahead and things were not right after that. I decided to change the spindle bearings and that has revealed another kettle of fish. I just got done fitting the new back bearing to slide properly so the preload could be set properly which it seems is impossible the way it comes from the factory. Hopefully this will at least get me back where I was pre part chatter catastrophe.

 

[mikey]

Good points, C-Bag. One assumes the lathe is workable as is but as you pointed out, this is not always the case.

My good friend owns an Emco Compact 8 and that lathe is amazing for such a small lathe. It was built to a tool room DIN standard, or so Emco says. That sucker took a 0.060" cut in 304 stainless with no problem, which impressed the heck out of me. No hint of chatter or strain with that cut, either. We then took a 0.070" cut in 6061, then shaved 0.0005" off the diameter.

I tend to forget that although the 9X lathes are clones of the Emco lathe, they are not built to the same standards. Thanks for reminding me.

 

[stioc]

Do you guys use HSS over carbide for any particular reason? because carbide inserts are just so much more convenient.

I'll admit part of the issue is user error too. I have so many hobbies that by the time I come around to using the lathe for a project I forget the basics sometimes (same thing happens with my other hobbies too). See my previous comment was based on a couple of projects I had recently done and was less than impressed with the lathe. Well last night I checked and I noticed the spindle speed was set to 400 RPM which was probably fine for whatever I previously did but the recent projects were aluminum and I only use carbide insert tools so 400 was way too slow for that combination. I probably should've been around 1000 RPM minimum. The machine will do 2000 RPM but I usually don't run it that high because the gears sound noisy and frankly I don't want something to come flying at me at that speed. Even at 1k RPM I usually stand off the to side just in case.

I also built a beefy four bolt compound mount for my 9x20 (using my CNC mill) but I didn't notice a big difference to be honest. I think part of the reason I also want a 12x36 lathe is because they are just better built, require much less fiddling and improving so you spend more time making projects on the lathe than for the lathe. Like the hand wheels etc are so smooth and just feel higher quality.

Don't get me wrong the 9x20 is a fantastic lathe for the price (it's the little guy of the bigger lathes, doesn't feel like a toy) and it's all I can fit in my garage/budget for now but I do dream of *upgrading* when/if I have more room. In the meantime I'll be giving my 9x20 some nice cleaning, lubing, adjusting and spending time tightening the nut behind the lathe.

 

[C-Bag]

The whole clone thing is insidious and it seems a misnomer. I rarely ever see an Emco but tons of Enco. There are so many different tags on the 9x, HF, Jet, Grizzley, Busy Bee etc. and each one would have you believe there is a difference. Some would have you believe their QC is better and others get the rejects but I'm not sure that's true and it's not more about chance that all the details align and you get a good one. They have to justify the huge price difference. Now it seems the 9x is going away as almost nobody carries it anymore.

 

[stioc]

Look what I just found in the manual...I guess I wasn't too far off in my .020" cuts? Alum alloys says rough feed rate should be between .015" to .030". It'll probably do more especially with carbide but this is what they recommend.

 

[mikey]

Do you guys use HSS over carbide for any particular reason? because carbide inserts are just so much more convenient.

HSS is cheaper, sharper and can be ground to cut with much lower cutting forces vs a carbide insert. A good HSS tool will allow a small lathe to cut like a bigger one, and it will also take micro-cuts that and insert cannot make. I've been using HSS, brazed carbide and inserted carbide tooling for over 30 years and there is no question in my mind that for most applications on a small lathe, HSS is usually the better choice. Like I pointed out before, my little Sherline lathe will easily outperform your 9" lathe with the right tool. It isn't the lathe; its the tool that makes that possible. The only thing about HSS tools, good ones anyway, is that you have to learn to grind them. For all the benefits they provide, I would encourage you to do so.

... Well last night I checked and I noticed the spindle speed was set to 400 RPM which was probably fine for whatever I previously did but the recent projects were aluminum and I only use carbide insert tools so 400 was way too slow for that combination. I probably should've been around 1000 RPM minimum. The machine will do 2000 RPM but I usually don't run it that high because the gears sound noisy and frankly I don't want something to come flying at me at that speed. Even at 1k RPM I usually stand off the to side just in case.

I turn aluminum at 2200 rpm all the time, with both HSS and carbide. Higher speeds reduce cutting forces, regardless of the tool type so chuck the work up tight and have at it. Your lathe is capable of far more than you might think.[/QUOTE]

 

[mikey]

The whole clone thing is insidious and it seems a misnomer. I rarely ever see an Emco but tons of Enco. There are so many different tags on the 9x, HF, Jet, Grizzley, Busy Bee etc. and each one would have you believe there is a difference. Some would have you believe their QC is better and others get the rejects but I'm not sure that's true and it's not more about chance that all the details align and you get a good one. They have to justify the huge price difference. Now it seems the 9x is going away as almost nobody carries it anymore.

I suspect that what happened is that the Chinese cloned the Emco Compact 8 after Emco split off their smaller lathes division, which was taken over by Profi Heim. The Compact 8 is still made by the Chinese but it is called a Compact 8E. They are NOT made to a DIN standard like the Compact 8 was, nor are the clones. Trust me; the Compact 8 is a fine lathe built with attention to detail that no asian clone has. I do agree with you that it is really difficult to sort out the better ones from the herd, what with all the marketing hype.