# mla tee slot cross slide



## eric chilton (Feb 5, 2019)

hi i was wondering if anyone has machined the metal lathes accessories tee slot cross slide for the atlas 10 /12 lathe ? ive had the casting for about 2 years and thinking about machining the part...........i know i can do it i just want to hear other peoples views on the complexity of the job ............thanks eric.......


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## jwmay (Feb 6, 2019)

I've probably had mine for the same amount of time, and have just recently begun reviewing the drawings and pricing end mills.   I tried to sub out one side of the thing, so I had one perfect flat side to work with, but nobody at work is interested. haha.  So maybe you and I can both try and work through it together.


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## eric chilton (Feb 6, 2019)

hi im trying to get Mr pete222 the YouTube shop teacher to do a series on it ..........i mentioned it to him and he didn't know it was available ..........there is a thread on practical machinist where a person named Paula does one for a south bend 9" lathe ...it very informative  with pictures and a lot of write up about doing it.........Paula did it on a seg mini mill/drill and it turned out great .......the problem im having is i have an enco Bridgeport clone with a 2speed motor.......i have a phase o matic converter running it .........but the converter do-sent recognize the lower speed of the motor....and in paulas thread im thinking the speed it was machined at was like 270 where on mine i can only go as low as 660 ..........i would hate to goof this up ...lol.............i have not machine a lot of cast iron .........i have bought all the tooling to do it just been putting it off .........the day i start on it im gonna have to lock the door and turn the phone off so i don't have any interruptions...................Eric


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## eric chilton (Feb 6, 2019)

jwmay look up the thread on practical machinist and in the mean time im gonna try and see if mr pete222 will do the series .......as free machining as cast iron is the only thing i see is getting under the crust layer ...........what i need to do is buy another one and send it to him ,,,,but right now funds wont allow ...............eric


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## yendor (Feb 6, 2019)

Here is a thread from another forum of a complete build.
The actual build and pictures starts about page 5-6 of the thread.






						MLA A-11 Milling Table - Machinist Web
					

MLA A-11 Milling Table Atlas Lathes



					www.machinistweb.com


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## jwmay (Feb 6, 2019)

So I'm thinking your intent is to fly cut it, or use a very large end mill for the facing cuts?  I only have a mill drill, so I don't suppose our plans will be the same.  You're going to be able to do it much faster I'm sure.  I'm going to read this link above.  I remember reading it before, but didn't know where it was at anymore.  Thank you yendor!


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## eric chilton (Feb 6, 2019)

jwmay i have an assortment of shars indexable r8 end mills from 1" to 3" im gonna use to mill mine with ......and i have the indexable dovetail cutter ......i just read thru the above link and im thinkin ..lol.....eric


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## jwmay (Feb 7, 2019)

The above linked isn't the one I've read before.  It seems to be written by someone like us, instead of this Paula you mentioned.  I've got an indexable dovetail cutter half made.  It's been that way ever since I got stumped on how to hold it while cutting out the insert landing...At least a year and a half.  Every time I run up against a wall that requires money to get over, the project stalls.  According to the PM article, we need a 5/16 t slot cutter, and a 1.375 inch 60 degree cutter.  I don't know if there's a difference with the Southbend MLA cross slide. I still have to figure out the professional way to sort out the 21/32" dimension with a 5/16 t slot cutter.  Up til now, I thought I had to use a 3/8" t slot cutter.  You've already got that stuff, so once again, you're ahead of the game, and I am behind the curve.


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## eric chilton (Feb 7, 2019)

jwmay can you hold the cutter in a 5c collet block in the vice to cut the land? i believe the cutter has a certain degree of clearance in that area .......from what ive seen on the south bend dovetail is taller than the atlas .....im not sure but just going by what i have seen in pictures of them .....on my atlas 12" 3996 lathe the cross slide dovetail measuring with a scale is a little shy of 0.3125 just by eyeballing it ........ i joined machinist web yesterday haha i should have along time ago but i have so  many websites and forums its hard to keep up with all the pass words and log in data lol........i read thru that thread and looked thru some others last nite that pertains to the mla a-11 cross slide..... the thread i was talking about is on practical machinist .......paula used an indexable apkt insert face mill to square the slide up with..............i know i can do this im just trying to figure out what cutters and speeds / feeds ...........i read on that other machinist web forum where they priced the job out and got prices of up to 1400.00 and the one guy the professor i think they call him said he would do one for 400.00 they estamated their time at about 24 hours to do it .......wow ..........im gonna have to do mine if it takes me a year ...lol........Eric...........


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## eric chilton (Feb 7, 2019)

jwmay you can mill it on a mill/drill ..........the link yendor posted they used a fly cutter and a  brased carbide bit to rough it out then finish cut it with hss.......... carbide to get under the crust /skin .......but carbide don't like an interrupted cut unless its a wmg type..............also they talked about the slide is got more material on one side if the dovetail area ..i havent had time to check mine yet ...and also they said that the tee slots need to be watched on spacing ..........................Eric


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## jwmay (Feb 7, 2019)

That’s a great idea! I’ll use a fly cutter for the dovetail. Thanks! I don’t have a collet block, or 5c collets. I do have an ER32 collet of the right size I think. I could probably turn a collet block on the lathe. I feel like I’m making progress already! Thanks again!


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## eric chilton (Feb 8, 2019)

jwmay the dovetail has to be cut with a 60 degree dovetail cutter or on a shaper......to mill it square you can fly cut it .......but the hss tool bit will get dull quick because of the sand in the casting on the outer layer .........go to shars tool and look up their 60 degree dovetail cutter i beleive it shows a spec on the clearances that you will need to make your cutter work right ...... also you could hold it in a vee block in the vice and take small cuts till you get to diameter ..................Eric.........


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## jwmay (Feb 9, 2019)

My shaper only has a 7” stroke, so that’s probably out. Although I imagine with careful setups, it could be managed. There are articles here about using a fly cutter for dovetails, so I guess that’s possible too. I did check my sparse collection of ER32 collets, and found one that may work. And I’ve got a suitable squarish block of metal to try to make a collet block from. Although at 20 dollars for one already made, I’m sure I’m not being efficient.


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## eric chilton (Feb 9, 2019)

yeah i hear you sometimes its cheaper to buy the tooling than make it .......banggood sells an er32 collet block ...........i have it but haven't used it yet ....i have the 5c collet blocks .........


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## jwmay (May 3, 2019)

I went ahead and got started.


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## eric chilton (May 4, 2019)

jwmay i still havent started mine .........business at my shop has picked up 100 % ......if you can keep posting about it .........i will really like to see the finished part .......thanks for posting that you started ...........Eric


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## jwmay (May 5, 2019)

Setting up to mill the slots. Pre traveled to every slot, and found a discrepancy I can’t reconcile yet. It seems like I’ve got 3 slots that’ll land correctly starting from the left and three that’ll land correctly starting from the right. I’m assuming it’s something I’m doing wrong. I’ve got more faith in the casting than in my skill.


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## jwmay (May 5, 2019)

This might be a very short and boring video of some work. Not really sure what I’m doing with YT. 

Any experts out there see a glaring error, feel free to advise me of it. I can see some less than professional things myself.


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## jwmay (May 6, 2019)

https://www.hobby-machinist.com/thr...slide-for-a-logan-11-as-promised.36473/page-2 

This just popped up recently, but it's a few years old, and it's a Southbend cross slide on a Logan lathe.  I'd say his write up is leagues better than what you'll get from me.  So, I figured I'd place it here for you to browse, in the event you didn't see it.


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## Buffalo21 (May 6, 2019)

I did one for my Atlas lathe, when I sold the lathe,the guy who bought it, threw the MLA piece in the pile for the scrapper. I thought it was a good product and it was a good project.


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## jwmay (May 6, 2019)

I’m definitely being forced out of my comfort zone with it. I assume that means I'm learning something. I can’t say I’ve got big plans for its use. I just remember the other Atlas I had was not quite as steady as I’d liked. This seems like an answer to that.


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## jwmay (May 7, 2019)

First t slot done. Not knowing what I’m doing, I decided forward progress was more important than equally spaced slots. Of course I will do my best, but the worst case is just not that bad. So here’s one down. Took an hour.


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## wa5cab (May 7, 2019)

The T-slot cross slide, other things being equal, is more rigid that the stock one with the compound.  However, without the compound and compound swivel, you can't cut threads properly.  So either adapt the compound and swivel to the T-slot or keep both.


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## jwmay (May 7, 2019)

Mr. Lofquist includes a drawing for a button to mount to the new cross slide which will enable the use of the compound.  As well as a new gib strip and set screws, he’s thought of everything it seems.


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## wa5cab (May 8, 2019)

OK.  Some of the T-Slot cross slides people have written up have been too tall to allow mounting of the stock compound with an AXA QCTP on it.


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## jwmay (May 8, 2019)

I’ll be sure and update the thread with what worked and what didn’t, provided I match print dimensions as specified.  My hope is to use the tool post that came with my Grizzly 4002. It’s larger than AXA, but I intend on mounting it directly to the cross slide.


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## Rob (May 9, 2019)

It will raise your compound considerably.  You will also loose your degree markings for setting the compound if you use his drawings for a button.  If you have a 12" lathe you can do what I did and go to a 10" compound and make a taller button.  I made it so it was the same height as my stock 12" compound and cross slide.  That way I don't have to reset the tool holders if I go back to the stock one.  I also put degree marks for all 360 degrees instead of just 180 degrees.


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## wa5cab (May 9, 2019)

Rob,

I know that the photos are just to show how you mounted the pintle and compound swivel.  But when you cock the compound aroud to 30 degrees, you should normally realign the QCTP square with the lathe's spindle axis.  The way that I do it is to temporarily mount a piece of solid round (I use a precision ground test bar that I have) in the chuck, slack the TP pinch bolt or nut, and advance the compound until the flat face of the TP is flat against the round bar, and tighten the bolt or nut.  With a Wedge type TP, you may have to put a #101 or 102 tool holder on the TP to register against the bar.


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## wa5cab (May 9, 2019)

And BTW, that looks like good work on the modification.


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## jwmay (May 9, 2019)

Unfortunately, I don’t have the 12” Atlas. Thank you for the pictures and explanation. I haven’t cut any sort of degree marks before. Honestly it looks both stressful and boring at the same time. In my case, with luck, the lathe will never be used for thread cutting. But I will keep the original compound and cross slide in case they’re needed. I use a protractor any time I need to set the compound accurately, so degree markings are also optional.


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## Rob (May 9, 2019)

One other issue you will find is that you will have to replace the square headed bolts with allen headed ones as it will be hard to tighten them against the MLA cross slide.


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## jwmay (May 9, 2019)

2 more slots done. I think each one is taking about an hour. This seems like a long time. I used a 5/16” corn cob type rougher on the “in progress” slot. I think this may help speed it up. And I’m pretty sure the t slot cutter will be dead by the end of this project. I’m probably doing many things wrong.


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## cdhknives (May 9, 2019)

I had to outsource mine.  It does stiffen the QCTP noticeably.  Overall I think you'll be happy with the end result.  I just use a protractor off the face of the chuck to set compound angles.  It is probably more accurate than the degree marks anyway!


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## jwmay (May 10, 2019)

Tee slots are done. The most efficient strategy was to use a 5/16 rougher at full depth, followed by a 3/8” 4 flute end mill at full depth, followed by the t slot cutter. This was at 317 rpm.  I’m estimating that cut the time in half at least. I’d started by slowly milling(3/8”) out the slots .020-.030” at a time. Which ended up being about  15 passes back and forth. So slow. Really no fun for me.


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## jwmay (May 10, 2019)

And here’s another remarkably boring video.


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## bill stupak (May 11, 2019)

wa5cab said:


> The T-slot cross slide, other things being equal, is more rigid that the stock one with the compound.  However, without the compound and compound swivel, you can't cut threads properly.  So either adapt the compound and swivel to the T-slot or keep both.


That is not necessarily correct, I have the MLA on my 12" Atlas with a solid block mount for the tool post and cut threads successfully just plunging straight in with the cross slide.  Stu


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## wa5cab (May 11, 2019)

Then you have been lucky or haven't had to thread across an interruption.  The reason for the practice of setting the compound around to 29.5 to 30 degrees is to insure that the half nuts are always pushed back against the leading edge of the threads on the lead screw.  If for some reason, you had to thread across a cross-hole, the carriage could tend to jump toward the headstock as the leading edge of the tool entered the hole with the trailing edge still cutting.  In general, you always want the reaction forces to be only in the direction to hold the half nuts firmly against the lead screw leading edge.  The same thing would tend to happen to the last half thread  if threading up to a pull-out relief groove.


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## bill stupak (May 12, 2019)

wa5cab said:


> Then you have been lucky or haven't had to thread across an interruption.  The reason for the practice of setting the compound around to 29.5 to 30 degrees is to insure that the half nuts are always pushed back against the leading edge of the threads on the lead screw.  If for some reason, you had to thread across a cross-hole, the carriage could tend to jump toward the headstock as the leading edge of the tool entered the hole with the trailing edge still cutting.  In general, you always want the reaction forces to be only in the direction to hold the half nuts firmly against the lead screw leading edge.  The same thing would tend to happen to the last half thread  if threading up to a pull-out relief groove.



I've never heard that explanation before, the common reason I'm aware of is that the cutting forces are less when the tool is just cutting one side of the thread. I do see your point and it does make sense. I've never had to single point with an interrupted cut before, so I'll keep that in mind. I can put the compound back on the cross slide, but much prefer the rigidity without it.  Stu


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## Shiseiji (Apr 30, 2020)

Do you have any suggestions for the gib? I managed to put a huge bow in mine. Still Haven't figured out how I did it but don't want to do it a second time. I held it in place with drill rod and adjustable parallels.


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## wa5cab (Apr 30, 2020)

Bill,

No.  The "common reason" is mostly false.  The volume of metal removed in either case is almost the same.  Feeding straight in some number of thousandths of an inch will be removing slightly more metal by volume (1/0.866 times what would be removed if the in-feed were done by the compound set at 30 deg.) and only half of it by the leading edge of the cutter.


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## wa5cab (Apr 30, 2020)

*Shiseiji,*

Which gib are you referring to?  If you mean the one for the T-slot cross slide, I assume that it came from the casting supplier as AFAIK the original Atlas 10-56 cross slide gib would be too short.  Or maybe he only supplied a drawing. And you or someone had to make the gib.  If you are talking about an Atlas 10-56, send me a PM.


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## jwmay (Apr 26, 2021)

Finished it.  But not really. I'm going to cut the sides down to match the width of the carriage. But it's useable. I'm guessing I've got 30 hours in it. I'm slow though. It was thirty hours over two years.


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## kcoffield (Apr 27, 2021)

jwmay said:


> Finished it. But not really. I'm going to cut the sides down to match the width of the carriage. But it's useable.


Why cut them down? I decided to keep the extra table surface.


jwmay said:


> But it's useable. I'm guessing I've got 30 hours in it. I'm slow though._* It was thirty hours over two years*_.


You were just very patiently allowing the it to naturally relax/stress relieve between operations....

Best,
Kelly


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## jwmay (Apr 28, 2021)

Seeing as how it took this long to get this far, I shouldn't make any promises on cutting the table more narrow. But if I get to it, it'll be for aesthetics.  I thought it might reduce levering forces on the dovetail as well.

Thanks guys!


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