Left hand threads on the LMS 3540 8.5x20 lathe

Four Corners

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I needed to cut some left hand threads the other day. In fact, I mostly wanted to try it. The manual says to swap one of the 42t gears with the spacer on the other shaft. Sounds simple. Not so much! I found that when I moved the banjo to engage the gear the A gear hit the spacer in its new position, or the B or C gears hit the box containing the electronics, or some combination of both. A quick call to LMS and Chris solved my problems. He said to ignore the chart in the manual and the one stuck to the machine, and use this instead: http://littlemachineshop.com/reference/change_gears.php. Brilliant! Just wanted to pass that along.
 
Good Find! I just got this same lathe about 2 months ago and have only had enough time to make one pass turning some aluminum. I am anxious to see what this lathe can do!
 
I am very pleased with my machine. I spent a ton of time aligning the tailstock (see Mr. Pete's vids), taking the slop out of the cross slide and compound and other bits and pieces like that. I fitted a cheap DRO from China, via eBay, and I'm very happy with that. I bought the four jaw chuck from LMS but stupidly didn't get the adapter plate. Won't make that mistake again. Making the plate was great practice, but never again! Making 1/2" thick, square pieces of plate round is no fun at all.

I hope you enjoy your machine. I am!

Check out Mr. Pete's video on the vertical shear lathe tool. Made one of those this evening. The finish it left on crappy steel from Rona was very impressive.
 
My tailstock appears to be very close but I havent checked it that thoroughly.
My cross slide is super smooth with no side to side or up and down play. It better be for all of the lapping compound I had to remove! My compound slide took a lot of adjustment to get it better than it was but it still needs work to meet my standards. The gib was bent pretty bad. I assume someone over tightened the gib screws while the slide was centered and the front and rear hanging because it bent the gib strip like a banana. LMS gave me a new gib strip but truthfully it all needs to be lapped together which will happen soon.
Where did you install the DRO? I have an extra igaging DRO scale I am thinking of putting on the tailstock. I measured each turn of the handwheel and I got about .038 to .0385 per turn. I need an extra hand to further check this and was thinking of adding a scale to the collar but I'm sure the DRO would be easier. Here is a link to Tom's Techniques and how he added graduations to a collar to make a dial.
Any specific Mr Pete vids you found helpful?

I forgot to add that I just purchased a used 4 jaw 5" chuck from LMS with the correct backing plate. The customer installed it and right away decided to go with a non-self-centering chuck so I got a great deal on it!
 
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The gib in my compound was also amazingly bent. Truthfully, I might have caused that. Don't know for sure. A few taps with a big hammer and some filing and lapping on water stones and it seems to be ok, ish now. I'm not totally happy with it, to be honest. It might be as good as I can expect from such a tiny machine.

This video from Mr. Pete is the one I was referring to in my post before:

The cross slide DRO is shown in the picture. Please excuse the mess. The machine is enjoyed a lot! The Z axis DRO is hanging off the back of the machine. I couldn't get a good view of it to take another picture. I'm sure you get the idea though. I'm glad I put them on the machine. That's how I realized how sloppy the cross slide was. It doesn't cut tapers now, unless I intend to.

There are so many more goodies at LMS that I want. Living in Canada means the shipping and border fees and so on means that buying anything from the US is a very painful experience. I had my machines shipped to Montana and i crossed the border and brought them back in my truck. It was still expensive, but it would have cost $1000 to ship them all the way from California. Crazy! Even a chuck on clearance would be stupidly expensive here. It's hard to even buy bits of metal to turn into chips. I might have picked the wrong new hobby.

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The DRO looks great. Are they glass scales? I have iGaging scales on my mini mill with Blu-Dro controller and a Android tablet. It works pretty good and I'm gonna add it to the lathe along with a carriage stop and lock. I've already drew up plans for a cam-lock carriage lock that pulls down on the carriage in the middle instead of the front or back.
I have some questions on how to adjust the tailstock specifically on this machine. Can I PM you or shoot you an email so I don't jack this thread. There aren't many users with the Sieg 8x lathes on the forums, well that I know of.
I also watched the MrPete vids on tailstock alignment and thats where I ran into several issues on other parts that effect the tailstock alignment.
Thanks
Brandon T
 
They are glass scales. The iGaging product with the BluDro look very good, but they are so expensive here, the regular DRO just made sense to me.

I'd be interested in your plans for the carriage lock. The one that the lathe has for the Z axis is not very good at all, in my opinion.

Please go ahead and PM me. I don't know how to receive those messages yet, but I'll figure it out.

Sent from my SM-N900W8 using Tapatalk
 
I sent you a message a while ago but I dont think it went through. When I click on your user name it gave me the option to start a conversation so I sent you a message. I dont know how to PM either. You can email me at 9t8z28@gmail.com I hope its allowed.
They are glass scales. The iGaging product with the BluDro look very good, but they are so expensive here, the regular DRO just made sense to me.

I'd be interested in your plans for the carriage lock. The one that the lathe has for the Z axis is not very good at all, in my opinion.

Please go ahead and PM me. I don't know how to receive those messages yet, but I'll figure it out.

Sent from my SM-N900W8 using Tapatalk
 
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