# Setting Angle On A-11 Cross Slide Equipped 10f



## cdhknives (Apr 25, 2016)

One hitch I have found in using my new A-11 cross slide.  It does not have any easy way that I can see to implement a protractor without adding more height, and the standard Atlas compound doesn't have a nice flat face for a handheld protractor.  The top of the slide is already a quarter inch or more taller than the standard slide, and I don't want to lose any more clearance if I can avoid it, so something under the compound is not preferred.  It would have to be very thin, and keyed to a slot or the face of the slide to work anyway.

So how do I set the 30 degree angle for threading, or will I have to switch back to the standard Atlas slide for this?

One thing I was able to do is scribe a line perpendicular to the ways, so I have a nice zero reference.  I just can't figure out how to get a protractor from the edge of the slide to the compound to set an angle for threading.


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## wa5cab (Apr 25, 2016)

Yep.  That's one of the reasons that I never have gone to the trouble to install the original Atlas double-holder (turret) cross slide that I have.  Because of the back-splash, installing it requires removal of the cross-feed screw bearing.  I have an extra cross slide that I could machine to fit on top but suspect that height would be a problem.


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## cdhknives (Apr 25, 2016)

I might try something like these round ones:

http://www.mcmaster.com/#protractors/=124zeyd

Add a zeroing notch, and it might be close enough for thread setting...even if I have to cut out the center so it lays around the base.  Hmmm....


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## Rob (Apr 25, 2016)

Not sure what to do for a 10" lathe.  Here is what I did for my 12".
	

		
			
		

		
	





I used a cross slide from a 10" atlas.  This works great and I made the marks for the full 360 degrees.


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## cdhknives (Apr 25, 2016)

Thanks Rob.  I remember seeing that pic of your setup somewhere previously.  The extra height for my 10" is undesirable to say the least...but it might be the best solution.  I rarely thread anything over 2" in diameter anyway.

I assume you have a indexing head for the 360 scribe lines...???  I could use the Atlas bull gear indexing but I think I only get 60 lines at 6 degrees each that way.  Good enough for the 30 degree threading index however.


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## Rob (Apr 25, 2016)

This is what I used to do the indexing.  I got a piece of 5/8th all thread and 2 coupling nuts.  I turned one down to a MT3 and the other at just a sharp taper.  I can then mount a degree wheel or a saw blade to use for indexing.  I think with your setup I would look at just a thin piece of sheet metal and one of these.  http://www.mcmaster.com/#protractors/=1250w8q . I would then set it up to be mounted to the underside of the button and keyed so you could move it to different slots.


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## Mondo (Apr 26, 2016)

I use my A11 only when I need to do some milling and the Atlas Milling adapter is too small for the work.  For this I added a vertical sliding table:  http://www.ebay.com/itm/171917219136  For anything else I just put the standard cross slide back on.  Easy-peasy.  My back splash is a concrete wall 18 inches from the lathe.

Indexing a compound on top of the A11 is going to present compromises.

Spiral_Chips


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## pdentrem (Apr 26, 2016)

You should use an adjustable protractor/triangle. I have the triple scale version, and it is very accurate. It is on the page you linked to.
Pierre


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## cdhknives (Apr 26, 2016)

Pierre, I have both manual and digital protractors.  I can't figure out how to use them properly.  The tool bit will present too small of a face.  The compound and toolpost are too high over the slide without major gymnastics.  The compound lacks a nice flat face down low.  All i can see to use is the index mark, but I need a scale to compare it to.  I guess a big protractor cut into a half moon and laid flat, using my X and Y scribed lines on the slide top to 'zero' it, is going to be my best bet until I can manufacture something more permanent.  I'd like to use the A11 slide as a general everyday tool because of the added mass and width should equal better rigidity.


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## RJSakowski (Apr 26, 2016)

cdhknives said:


> One hitch I have found in using my new A-11 cross slide.  It does not have any easy way that I can see to implement a protractor without adding more height, and the standard Atlas compound doesn't have a nice flat face for a handheld protractor.  The top of the slide is already a quarter inch or more taller than the standard slide, and I don't want to lose any more clearance if I can avoid it, so something under the compound is not preferred.  It would have to be very thin, and keyed to a slot or the face of the slide to work anyway.
> 
> So how do I set the 30 degree angle for threading, or will I have to switch back to the standard Atlas slide for this?
> 
> One thing I was able to do is scribe a line perpendicular to the ways, so I have a nice zero reference.  I just can't figure out how to get a protractor from the edge of the slide to the compound to set an angle for threading.


Here is what I did to quickly and easily set the compound angle for threading.
http://www.hobby-machinist.com/threads/29-5-deg-angle-tool-for-lathe.34541/#post-299346


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## pdentrem (Apr 26, 2016)

How about this. Print a degree wheel on plastic film or paper, at the correct diameter and glue it to either the compound directly or to a thin steel disk which is then sandwiched between the slide and the top swivel. Naturally you would have to cut away the paper/plastic that is directly under the swivel and stop it from turning randomly, a small pin through the steel backer could do that.

I looked for a small metal degree wheel such as used for timing cam shafts on line but have not found one in a sub 4 diameter as of yet. Mac master Carr sells plastic ones in 3 and 4" in self adhesive towards the bottom of the page.

I found the Incra Precision Protractor. You could use it to scribe your lines via the built in slots on the protractor. Check out their YouTube video.
Pierre


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## cdhknives (Apr 27, 2016)

Been looking at the self adhesive ones...even if just to mark a dot for the 29 degree setting.  I've never had to set anything else.

RJ, neat idea, but there are no long flat edges on the Atlas compound for me to index from.  It's a casting and rounded at the base.  Your cut down angle bracket would have nothing to index against.


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## dgehricke (May 10, 2016)

This is what I did on mine, my lathe is an Atlas 10f I also made some special tool holders for the lathe so this height would not be a problem.
I purchased and extra pot slide from eBay and cut it down then I put it in a 3 Jaw by the spigot  and machined off the excess so heres the results. 
I'll post some photos of the tool holders later.
Regards
dgehricke


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## wa5cab (May 11, 2016)

I had been thinking of doing exactly that so that I can use the Atlas (actually sold as Craftsman since it fits a 12") Cross Slide Turret (double) without losing use of the compound.  But I was thinking along the lines of machining a key to fit the T-slots into the bottom.


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## dgehricke (May 11, 2016)

Thats exactly what I did to hold the piece to the slide if you look closely at the spigot there is an allen cap bolt ¼-20 holding it, works well.


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## Mondo (May 11, 2016)

With a mill and some clever aligning one could leave a raised guide on the bottom so the resulting plate will automatically index to the A11 slots.

Spiral_Chips


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## wa5cab (May 11, 2016)

That's the key that I was referring to.


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