Is it posible to make a thread chasing dial?

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tarmo120

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The lathe I got doesn't have that dial, you would use when threading. And because of that I need to keep the halfnuts connected and run the motor backwards after each cut.
I really hate that. This got me thinking, would it be possible to make my own thread chasing dial.
If this is not possible, I'll just have to live with what i've got.
 
It should be possible. All a thread chasing dial is, is a gear that engages with your leadscrew, a dial with markings (usually 8), and a mount. The gear needs to be the right pitch to engage your leadscrew. It doesn't need to be a tight fit, just enough so that it doesn't jump around.
 
Yeah, easy enough to make. Just count your leadscrew pitch and make your dial gear to suit, *important bit* keep the gear pitch in ratio relationship to the leadscrew. ie if your leadscrew is 8tpi then make the gear 16 or 24 tooth. for a 6tpi leadscrew, then 12, 18, 24 etc. Makes for easier re-engagement calculations on the threading dial marks.

Cheers Phil
 
What kind of lathe do you have? Would it be for metric, SAE threading, or both? It will make a difference as to how many teeth you need and the markings on it else, as the others have said, it should be pretty easy to make one.

-Ron
 
If it's for that same Nova lathe you posted, you can see on the PM version what their's looks like. PM1127VF

May be easier to just purchase one but not sure if you'd be willing to spend that much on one. Grizzly has this one in stock for $117 which is for the G0602. I assume your lathe would have a metric leadscrew so you'd have to verify the gear pitch or just replace it. I only referenced Grizzly cause their the only one I know that lists & sells replacement parts online. Maybe try calling someone in your area.
 
In my opinion making this can be kept simple you dont need overkill. A couple of basic tools. I have
done this and worked better than expected. A block of mahogony an old exhaust valve and a piece of
delrin or similar. The thought is, that this will not be towing a Mack truck. It practically has no load on
it. I counter sunk the valve & drilled the block for the valve stem. I brushed on the blackest grease/oil
on the lead screw and rolled the delrin to get the imprint (mine is acme) die grinder with cut off I cut
the teeth on the bench vice. As you get a pretty good mesh thats good enough. I dont know If you
have a mounting hole like south bends or you will have to drill one for a pin. Valves are hard so I cherry
redded it so I could stamp lines and numbers (8). The plastic driven gear is only hand pressed on the
valve. I dont have to index or time this because I placed a large washer on the top & around the
valve with a witness mark so when I engauge the half nut just notice where and turn the ring or
washer to the number you wish to use. Couple coats of kilz couple coats of gray and nobody can tell
its made out of wood. I should Have said I counter sunk the valve with a forestner <(spelling) bit.
I suppose if you have a flat spot on your cross slide you could glue a magnet to the new dial block.
As I hate all the math most do for a simple little gear, the simple things are overlooked a foot print
is a footprint it will reveil all the angles pitches fingerprints no math it works.
 
Yes I was wondering if I could make it for the Nova lathe. I would have asked around locally, but I bought the lathe from Finland and they don't sell any lathe with this dial.
So that means, they wont have any dials available.

I am very interested in your method, GK.
Could you explain to me how you cut the mesh on the pinion.
Did you make up a special cutter and milled it on a rotary table or what?

Oh yeah, and I'm 99% sure this lathe has a metric leadscrew. I can thread metric and imperial/inch threads with changing the gears.
I'm going to where the lathe is on friday, so I could check that leadscrew it is.
Is it written on something or in the manual or just look at it?
 
This is one I made years ago for a South Bend lathe. I was fortunate enough to buy the gear just before South Bend folded.

Ken

T_DIAL1.jpg T_DIAL2A.gif
 
This is all very nice and now I'm convinced I can make one. But my question is how did you cut the gear.
Because I'm confident you or I wont find a macthing gear.
If I have a matching gear for the leadscrew, the rest is very easy.
 
It doesn't have to be an exact match, because you are not transmitting a lot of load. Figure out if your leadscrew is imperial, or metric, then figure out the pitch. Find a 16tooth gear with the same pitch,and it should fit, no problem. Even if you can't machine it, you may be able to find a small plastic gear for sale, or somebody on the board may be able to make one for you.

Making gears isn't too hard, Brian has a nice thread on building the tools and cutters needed to make clock gears.

[thread]9737[/thread]

I'm guessing your lathe is going to have a metric leadscrew that will mesh nicely with a standard metric gear.
 
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