can anyone identify this model?

i believe they are closing properly? I don't believe there supposed to close right tight together? hard to tell in the pic I put up but there doesn't seem to be a lot of thread depth there...
 
I don't know the intentions of the Logan designer but have always assumed that half nuts should close completely. Take your pair (loose) and clamp them closed around the lead screw down near the right end where there shouldn't be an wear on the screw threads. Measure the end float of the nut. Do the same thing up in the area where the nut would be when the carriage is near the chuck. The difference is screw wear. Repeat the two tests with a new pair of half nuts if you can. The differences in end float between the two sets of half nuts would be attributable to nut wear.

Install the old nuts and then the new nuts in the apron, position the carriage so that the half nuts are in the same location on the lead screw as in the second test and measure the carriage end float. The difference between the half nut end float and the carriage end float will be due to looseness and wear in the half nut closing mechanism. Not having a parts manual I can't say which parts you might want to replace.
 
i'll have to take the apron off and remove the half nuts to try that properly I guess.. is there a certain gear the lathe should be set in for general work....not thread cutting? I know mine was set slow as hell and I was trying to diagnose things so I put it on a different gear setup to move things along.... I really think new half nuts are in order but I'm not in a hurry for that....broke the belt today, now gottta look into where a person gets leather belts? seems I'm 1 step fwd and 4 back on this thing
 
RA,

Typical feeds per spindle revolution are perhaps in the range of 0.002" to 0.008". On my Atlas 12", I usually use 0.0042 or 0.0044 (which are its two slowest feeds) for finish and 0.0078" for roughing.

On some machines, it is possible to pull the half nuts without pulling the spindle. However, in you case I would pull the apron first so that you can see what it is doing.
 
wa5 I'm new to all this so your .0002" doesn't mean much to me...I would need to add subtract gears to make it work for a certain thread... no knowing what speed that would be? pulling the apron is not a bad job I will maybe try to find time tomoro... still need to track down a belt b4 I can do anything...
 
wa5 I'm new to all this so your .0002" doesn't mean much to me...I would need to add subtract gears to make it work for a certain thread... no knowing what speed that would be? pulling the apron is not a bad job I will maybe try to find time tomoro... still need to track down a belt b4 I can do anything...

rambin, There are three belt options. Logan sells a glued belt that requires spindle removal. Some folks have also used serpentine belts from the auto parts store, but that option also
requires that the spindle be removed. Logan can also sell you a belt with a clip that can be used without removing the spindle: http://store.lathe.com/drive.html. If you decide to order
from Logan, be sure you have your serial number handy when you call: they'll ask for it.
 
RA,

Carriage feed rates are independent of spindle RPM. They are measured in inches per one spindle revolution. The speed that the carriage moves to the left is a function of both feed rate and spindle RPM. But how much it moves for each revolution of the spindle is not.affected by RPM of the spindle.
 
rambin, There are three belt options. Logan sells a glued belt that requires spindle removal. Some folks have also used serpentine belts from the auto parts store, but that option also
requires that the spindle be removed. Logan can also sell you a belt with a clip that can be used without removing the spindle: http://store.lathe.com/drive.html. If you decide to order
from Logan, be sure you have your serial number handy when you call: they'll ask for it.


the leather belt that broke appeared to be stapled together somehow...since I don't know how to remove the spindle im probably going to look into a belt with a clip. I know the local menonites use a lot of belt driven tools im thinking they might be a source foor a replacement leather belt.. will have to look into that when I get a chance...
 
RA,

Carriage feed rates are independent of spindle RPM. They are measured in inches per one spindle revolution. The speed that the carriage moves to the left is a function of both feed rate and spindle RPM. But how much it moves for each revolution of the spindle is not.affected by RPM of the spindle.

the carriage feed speed is controlled by the gear combinations(no quick change on this machine), am I not correct? im asking what gear settting I should normaly run in...what combination
 
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