Finally Threads !! How do you set change gears on mini lathe for threading?

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V 45

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How do you set change gears on mini lathe for threading? I have a 7x16 Micro mark lathe. I want to cut 7/16"x 20 threads. Looking in the booklet it states (A)= 40 and (D)= 50 ... on the change gear cover it states (A)=40, (B)=65,and (D)=50 !!! So which one do you use ? Also, I have tried to match these up on the lathe and none of the combinations line up to make any contact with (D). I loosened the bracket that (C)and (B) ride on and still no contact...what am I doing wrong here ? This will be my first threading on my lathe.
Thanx again for help !!
V 45

Here is where my post went...So again after a few trials of failure I finally made my first threads !! My biggest issue was I had my compound set at the wrong angle...59 instead of the 29 1/2 degrees !! I had used the gauge on the compound not realizing it wasn't the 29 1/2 I was needing. I got that corrected and made my first threads...made the gadget with the nut in the middle. These threads are 7/16 x 20. It was a very good learning project.
Thanx again for everyones help !!!
V 45


Threadsfinally.jpg


threadgadget.jpg

 
Hi V

Send us a picture of the end of the lathe with the banjo bracket and gears and perhaps we can help.

:)

Dave
 
Here is one with a 45 on (C) and doesn't touch (D) I don't have any others that would come close. I'm adding the following...A has a 40, B has a 65, and D with a 50...with C being 45

with45gear.jpg
 
OK

I see what appears to be the screw gear on the lower right...is that correct?

Assuming it is, is there any room to slide that intermediate gear behind it and get it to mesh?

Then rotate the banjo up to mesh with the stud gear?

Whats the spacer on the other side of the screw gear look like?

Dave

 
Steamer... The Bottom right is the lead screw gear.... Behind that the spacer is fixed to the shaft (I think) or at least pressed on. I'm guessing that you are calling the intermeadiate gear the one in the middle with 2 gears on the stud. That is pushed up to mesh with the drive gear on top. There is no room to just mesh with the B gear (inner one on stud) if that makes sense?
 
Hi V

Take the gear set in the middle out...the ones next to the leadscrew or "screw" gear.

Whats behind that ...is it mounted in a slotted rail?

Dave
 
Usually change gears have a double keyway on the bores....the spacer probably has that two...but I can't tell from your pictures...yet. ::)

Dave
 
Dave I have a micro mark lathe the screw gear has a sleeve on it. When you pull the gear off you can flip the sleeve over to get the gear to mess with the Idle gear. This is how you use three gears. The compound gear is not used.

Don
 
HI Dave, Shows how little I know about editing !! So here are a couple more.
Banjoplate.jpg


side view
plate2.jpg


Thanx again,
Dave
 
V45 the screw gear shaft has a sleeve on it pull it out and place your gear into the shaft and put the sleeve inbehind the gear. This will set you up for three gears then adjust the slotted bar to mess them.

Don
 
Thank you Steamer and Don...I will try it tomorrow...Need my beauty rest for work...believe me I need it :D
 
Not sure how I did that but my reply went into the very first post I made...see update in that one...Thanx again !!
 

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