# Logan 200 Lead Screw Speed And Chuck Removal



## vincent52100 (Mar 4, 2015)

Good evening. I have a Logan 200 with a couple of issues. They may be a lack of knowledge on my part. The lead screw speed seems to be a bit fast. I can't really get a good finish, it looks kind of like threads although very close together. The gear on the lead screw is 72 teeth. The gears on the idler are 60 and 32 teeth. Does that seem like a good speed?  
Also I can't remove the 3 jaw chuck. I'd like to install the 4 jaw but don't want to damage anything getting the chuck off. Thanks


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## TomKro (Mar 4, 2015)

I can't help with the gear selection, but there's a number of things you can do to remove the chuck.
I locked a long hex nut (a threaded rod connector) in the chuck and used a socket and a breaker bar to pop it loose.  I was also worried about breaking parts, so I avoided locking anything up.  I believe other folks used soft wood into the gears to jam them up to have something to turn against.


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## vincent52100 (Mar 5, 2015)

Thanks, I'll try the rod connector method.


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## Mister Ed (Mar 5, 2015)

Look at the following. I usually run in some configuration of figure #3. Which figure is your lathe set up now? And what gears do you have where? Also, do you have a full set of gears? If not what do you have?


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## vincent52100 (Mar 5, 2015)

Thanks for your answer. If I'm looking at figure 1 right the spur gear is 18t, the big idler gear 60 and the small is 32, the screw gear is 72. I don't have any other gears. The machine came with a set of change gears but their not for this machine (the PO said that they would not fit). I intend to make a list of them and see if someone can identify. Maybe I'll be able to trade them with someone. I'll post pictures and dimensions. Thanks


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## vincent52100 (Mar 5, 2015)

I meant to attach a picture of the gear train.


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## Mister Ed (Mar 5, 2015)

LOL, I was just going to say post a pic ... and you did before I posted. That configuration is not even on the charts ... had telling what thread pitch you are actually cutting. Here is what the lathe would have had for a full set of gears. You don't need all of them, acquire them as you go and as the need arises. But to start with I would get a 24, 54, & 48 ... that way you could set up like pic #3 and have your 32 on the stud and the 72 on the screw. That would give you .0092"/rev.

I do have some extra gears, I can inventory once the temps break and let you know.
Oh, nice looking lathe as well (presuming its the one in your avatar).


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## vincent52100 (Mar 5, 2015)

Thanks! Yep, thats the one. Really happy with it. I've done a couple of small things with it, not complicated parts but expensive to buy.


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## Mister Ed (Mar 6, 2015)

Oh and to set up like diagram 2 or 3, you will need another stud assembly like your 60 & 32 are mounted on.


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## vincent52100 (Mar 6, 2015)

Looks like I'll need to do some shopping


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## vincent52100 (Mar 7, 2015)

I've listed the change gears I have in a separate post (Logan 200 change gears)


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## Mister Ed (Mar 7, 2015)

Just sitting here (wasting time) you are running a feed of about .0171"/rev or 58.3 threads per inch.
Calculated as follows:
18:60 = 0.3000
30:70 = 0.457143
Reduction in one rev = 0.137143 (reductions above multiplied together)
Since Logan leads crews have a pitch of 8tpi (0.125) multiply the reduction by the 0.125 "/rev.


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## vincent52100 (Mar 16, 2015)

Would these be the stud aasy I need? Thanks
http://www.ebay.com/itm/Logan-10-La...931?pt=LH_DefaultDomain_0&hash=item2eddea180b


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## Mister Ed (Mar 16, 2015)

To me, something does not look right ... missing bushings and spacers at minimum.
I am remembering something more like these:
http://www.ebay.com/itm/Logan-10-La...376?pt=LH_DefaultDomain_0&hash=item58bee6ea68
I think in the pic, the top one, has the bushing on backwards.

You must have one on your lathe now (has the 60 & 32 gear on it) pull it off and have a look.


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## vincent52100 (Mar 18, 2015)

Will do. Thanks


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## Mork (Jul 4, 2015)

My Logan 200 came with 6 gears. Fortunately it was configured for a slow feed rate. After scratching my head for a while I realized i was missing quite a few gears and a stud to configure like Fig. 2 of the gear chart. After three ebay transactions I now have the 17 gears needed for all combinations. Realistically 15 is enough but you will be taking apart stacked gear combination. Having 2 extra gears help speed things up when changing gears.

I'm not sure what the Lathe originally came with but here's what I recommend. For most work leave the lathe configured for "next to the slowest" feed rate. The slowest rate is fine also but will require you to move more gears when you want to thread. This allows you to leave the 72 tooth gear on the idler shaft for most threading. The 72 tooth can be used in other positions for slow feed rates but they really are not that important.

Here's the gears I think you need:

24 tooth
32 (need two of these)
36
40
44
46
48
52
54
56
60
72 (on idler stud)
24/48 stacked gears on bushing
18/54 stacked gears on bushing

Here's a picture of the gears I have (note the 72 tooth on the stud) and what I would call my standard configuration.


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