# Information needed regarding "Carriage Feed"



## littlejack (Jan 9, 2014)

Hey fellas:
  I got the lathe (10" QC54) mounted and belts changed out last night. I also changed the drive belt to the biggest pulley on the  
  countershaft, to slow things down a bit.
  Afterwards, I was running it and checking things out. I put the "left hand" lever in E position, and the "slider" lever in the no. 9 hole. This is
  supposed to be the slowest setting for the feed, .0042.                                                             
  I set a dial indicator behind the carriage (tail stock end) and ran the lathe to take out the slack then zeroed the indicator. I then turned the  
  chuck by hand, one full revolution. The dial indicator read .008. I repeated this a couple of times, with the same .008 reading.
  Question: Did I do it wrong? Isn't it supposed to read .0042? 
  I need some tutoring.
  Jack


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## Mondo (Jan 9, 2014)

My interpretation of the charts (I do not have my 12" QCGB lathe assembled so I can't test this) is:
To get carriage advance of .0042" per spindle revolution:
LH lever: Position E engaged.
RH lever: Position 9 (extreme right)
Sliding gear on quadrant: OUT to engage the 16 tooth compound gear.


So check the sliding gear in the quadrant on the side of the headstock. It sounds to me like it is in the "in" position engaging the 32 tooth compound gear.


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## littlejack (Jan 9, 2014)

Spiral Chips, thank you very much for your reply. I will check that gear position when I get may chores/honey-do's done. 
  That shows how much I do not know about these machines. 
  I figured that when they say "Quick Change" all there was to do was to change the position of the two exposed levers.
  Now, knowing that there IS another procedure to change the carriage speed, that would explain why, when setting the TPI, that the
  feed looks to be too fast for cutting threads.  Would this be correct also?
  Is there any site on the net that goes through the procedures of setting the QC gear box for all operations? 
  I have the Manual of Lathe Operation, but it does not cover that.
  I am certainly glad that there are machine operators here that are willing to help the novice. Thank you all very much.
  Jack


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## littlejack (Jan 9, 2014)

According to my Atlas Parts List schematic from Clausing, the sliding gear shown is a 40-T. I checked mine, and it is indeed the same. So, I am right back where I started. 
 If anyone knows why the Carriage Feed on my lathe is a measured .008 instead of the proper .0042, it would be greatly appreciated if they would chime in.
  Jack


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## kd4gij (Jan 9, 2014)

Yes the slide gear is 40th meshes with a compound gear that has 32th in the back and 16th gear in the front.you wan't to be in the out position riding on the 16th.


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## littlejack (Jan 9, 2014)

By golly, you fellas nailed it.
 It took me some head scratching while looking at all those gears. The "sliding gear" literally slides, DUH?
  Now, there must be a pictorial book/manual that has all of this information? Where can I find one?
  Fellas, thank you very much for the help and instruction.
  Oh yea, I set up the dial indicator again, and it moved the proper .004 +/-. Imagine that. 
  Regards
  Jack


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## Mondo (Jan 10, 2014)

Yahoo groups has a very active Atlas/Craftsman machines group:  http://groups.yahoo.com/group/atlas_craftsman/
That group has a "Files" section that contains a plethora of Atlas/Craftsman lathe documentation.  There are three QCGB manual there that you can download in pdf format.   You may need to download all three and compare them to what you have to determine which is correct for your model.  

You will need to apply for membership in the group to gain access to the files, but that isn't much different than applying for membership to this forum.


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## mattygee (Jan 10, 2014)

I was able to squeeze an extra 40/20 compound gear into the train to give me a .0021 slow feed rate.  Handy when turning larger diameters. On the rare occasion (heck, its rare I even use the lathe these days) I thread, I just double the thread count on the QC.


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## littlejack (Jan 10, 2014)

Thanks fellas for your posts and information. 
I think I will be good to go (for a couple hours) until something else comes up. 
  Regards
  Jack


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## kd4gij (Jan 10, 2014)

Glad to hear it all worked out. Now have fun. Any other questions come up ask away. And remember The only dumb question is the one that didn't get asked.


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## wa5cab (Jan 11, 2014)

Jack,

Look at the chart on the front of your QC box.  Just left of center is a column headed "SLIDE GEAR".   From top to bottom, it reads IN, OUT, OUT, OUT, OUT.  This is the column that tells you where the sliding gear should be.  The IN position is only used when you need to cut threads between 4 and 7.5 TPI.  So 99% of the time, the gear should be OUT.  There is a drawing of the chart in the earliest 12" GB manual but not the latest and not in the 10" box manual.  I'm not sure about the middle 12" one as although I have a hard copy, I can't lay my hands on it right now and we don't have a scan of it.  

The Yahoo Atlas_Craftsman Group Files section has manuals on the ATLAS 1500 and 1570 10" boxes and the first and third version Craftsman 12" boxes.  This site (H-M) had the same files in Downloads but I haven't yet had time to check whether they survived the crash and the several month hiatus.  We are slowly getting it back up and running with new software (previous provider went out of business).

Robert D.


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## littlejack (Jan 11, 2014)

Robert:
  Thanks for the post. 
Leaving the slide gear in the "out" position, will make my life much more simple. I like simple.
  Jack


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## DennisV (Nov 4, 2014)

I'm very new to this. Would it be correct to assume that I can use a compound gear from a pre quick change atlas 10" machine to accomplish the slower feed speed?


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## Dranreb (Nov 4, 2014)

DennisV said:


> I'm very new to this. Would it be correct to assume that I can use a compound gear from a pre quick change atlas 10" machine to accomplish the slower feed speed?



You certainly can Dennis, you can also cut metric threads by changing one of the twin gears next to the g/box, I've done both and it works fine for me. 

However,  there is a simple way (cleverly worked out by Atlas-owner Carvel Webb)  to generate a limited range of the more common metric pitches. Because  the 30 t.p.i.,  24 t.p.i and 20 t.p.i positions represented the same  ratio intervals as 1 mm, 1.25 mm and 1.5 mm pitch if one could convert  the 30 t.p.i. position to 1 mm pitch, then the 24 t.p.i and 20 t.p.i  positions would correspond to 1.25m and 1.5 mm. Now, 30 t.p.i = 25.4/30 =  0.8467 mm. Close, but not close enough, so how to get this closer to 1  mm ? Using 52 and 44-tooth gears gives 0.8467 x 52/44 = 1.0006 mm -  which is almost spot-on. The tumbler gears in the Atlas set include a  32/16 shielded gear driving a 40 tooth sliding gear which in turn drives  the box through a back-to-back pair of 48-tooth idlers. Because the  52/44 combination fits neatly in place of the 48/48 idler the job can be  done. With the 40-tooth sliding gear engaging the 52-tooth gear to the  box, the 52-tooth gear is acting as an idler (with the 44-tooth gear as  its spacer) and the gearbox operates in its normal `Imperial Mode' - but  with the exception of the coarsest (seldom-used) range. However, with  the 40-tooth sliding gear in the other position, it engages the 44-tooth  gear of the 52/44 combination and introduces the 52/44 ratio into the  train. The 30, 24 and 20 positions, or 60, 48  and 40 positions, become  the desired 1 mm, 1.25 mm and 1.5 mm pitches, depending upon whether the  52-tooth gear of the 52/44 pair has been placed closest to, or away  from, the headstock. However, placing it away from the headstock  maintains the bulk of the t.p.i. and feed settings (as per the chart on  the gearbox). It also means that it's not necessary to remember to  double everything - as would be the case if the sliding gear was driving  off the 32-tooth part of the shielded tumbler gear. All that is now  required to switch between the normal "Imperial Mode" and the "Basic  Metric Mode" is the few seconds it takes to loosen the yoke and to move  the sliding gear in or out.

This was taken from this excellent site: http://www.lathes.co.uk/atlas/page11.html

Bernard


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## DennisV (Nov 4, 2014)

Thanks Bernard, for the help. I'll start looking for the gears and stud as time permits. thanks again


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