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Lead Screw issue

grover99

Plastic
Joined
Nov 14, 2010
Location
missouri
Hello: I am very much a newbie when it comes to machining. I have a 9C south bend lathe and a 60s era bigger lathe. I’m slowly getting better using the lathe.

I am now trying to get an older mill working. The machine itself seems to work fairly decent. However, the lead screw and nut for the side to side movement is stripped out. It is also is missing the spacer piece(jib maybe), for one side of the bed. The lead screw is metric. I believe it is a 3 acme thread.

Does anyone have any recommendations on how to get a new screw and nut and where to get the spacer piece.

Another thought we have, since we are only going to be doing small pieces, is to get a compound vice and mount it to the bed and not use the controls for the bed.

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What is the brand of the mill? Model and year too.

Compound vices are just next level garbage in general.
 
I remake lead/feed screws, if you can’t find a replacement let me know and I can probably help you out. But as stated above to even begin to look for a replacement we need more information on the mill.
 
I will post a couple pics tomorrow. It is an older machine. I haven’t been able to find it online, but I don’t have the model number at home. I do know that it is a Drillmaster and the speed change control looks similar to an enco that I have seen.

Chris
 
A bit of a clue for us all would be what graduations there are on the handwheel (ie what one full turn would be) and how many starts there are. That would help to find the correct pitch/lead. Also is it left or right hand. I just got a 2 foot length of 3/4" x 10 tpi left hand acme threaded bar from Roton to make a new cross feed shaft and bronze nut for a friends Kerry. Roton might be a good start to save you having to make the screw yourself. You may be lucky enough to find a tap. I wasn't and had to screwcut it, which was no problem once the tool was made
 
A bit of a clue for us all would be what graduations there are on the handwheel (ie what one full turn would be) and how many starts there are. That would help to find the correct pitch/lead. Also is it left or right hand. I just got a 2 foot length of 3/4" x 10 tpi left hand acme threaded bar from Roton to make a new cross feed shaft and bronze nut for a friends Kerry. Roton might be a good start to save you having to make the screw yourself. You may be lucky enough to find a tap. I wasn't and had to screwcut it, which was no problem once the tool was made

Honestly if he needs to make the screw himself and it’s a nonstandard dia/pitch, if possible I’d just use a standard dia/pitch thread that matches the original pitch. Say for example if it’s something like 7/8-8 LH, it’d be easier to use 3/4-8 LH provided everything would fit appropriately.
 
Here is a pic of the mill. There are no model numbers anywhere.
 

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Almost looks like someone married a Clausing drill head to a mill/drill base. If so, the drill head is not suitable for use as a milling machine.

Tom

Tom: Since I don’t know much, how would I tell if this is a mill or drill press? It doesn’t seem to be a marriage of 2 different machines, but I don’t know for sure.
 

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What’s the taper in the spindle? Is there an easy way to quickly remove a tool from the spindle? Are there collets?

If it’s a Morse taper without a drawbar then you can be pretty sure it isn’t for milling. But really the vertical column looks to me like a drill press.

Tom: Since I don’t know much, how would I tell if this is a mill or drill press? It doesn’t seem to be a marriage of 2 different machines, but I don’t know for sure.
 
What’s the taper in the spindle? Is there an easy way to quickly remove a tool from the spindle? Are there collets?

If it’s a Morse taper without a drawbar then you can be pretty sure it isn’t for milling. But really the vertical column looks to me like a drill press.

It takes R8 collets.

Chris
 
there is no such thing as a 3mm acme thread

US leadscrews are often eight threads per inch, which would be 3.175 mm pitch, close enough to 3mm to be confusing.

I'd measure the leadscrew pitch by counting turns over its whole measured length, and doing the math. Or, use a thread guage, if available.
 








 
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