POTD- PROJECT OF THE DAY: What Did You Make In Your Shop Today?

[Alcap]

Like most members we start one project but need another to get the first one done . My cross slide screw was worn on my 5914 lathe , running the carriage in exposed the nasty looking threads , Another member on HM did a repair on his by getting a length of 5/8”-10 LH and mating to his . Ordered it last summer but was putting it off ,we’ll time has come to get going . Needing to machine the new threaded rod thought this would be a good time to make a spindle spider , my lathe has 3 taped 10-32 holes on the end of the spindle . I found a scrap that would make a nice spider . I counter bored it tried out the dividing head for the first time to drill and counter bore for the socket head cap screws . I was hoping to use 4 screws to hold work pieces . My cardboard template doesn’t give me any hope so unless someone has another way I’ll just use three screws .

 

[woodchucker]

Like most members we start one project but need another to get the first one done . My cross slide screw was worn on my 5914 lathe , running the carriage in exposed the nasty looking threads , Another member on HM did a repair on his by getting a length of 5/8”-10 LH and mating to his . Ordered it last summer but was putting it off ,we’ll time has come to get going . Needing to machine the new threaded rod thought this would be a good time to make a spindle spider , my lathe has 3 taped 10-32 holes on the end of the spindle . I found a scrap that would make a nice spider . I counter bored it tried out the dividing head for the first time to drill and counter bore for the socket head cap screws . I was hoping to use 4 screws to hold work pieces . My cardboard template doesn’t give me any hope so unless someone has another way I’ll just use three screws .

Three should be fine, that's what a steady rest is.

 

[finsruskw]

I don't quite get how that would work.
You advance the cross slide instead of the compound then?

Is there a discussion here for just treading questions?

 

[woodchucker]

I don't quite get how that would work.
You advance the cross slide instead of the compound then?

yep, but you have to keep track of where you were last cut, so you can gauge how much to advance.
eh..

 

[finsruskw]

I will try that.
I have just been cranking the cross slide out one turn, hit reverse to return leaving the 1/2 nuts engaged, then advancing the compound like .005, then returning the X slide back to zero and taking a cut.

I thought that was the correct way.

 

[davek181]

Ask ten machinists how to do one thing and you will get fifteen answers. Most or all of them will be right.

 

[savarin]

I thread at 90' because I have replaced the top slide (compound) with a solid plinth so there is no other way.
Yes advance the cross slide to give the cut.
as 99% of my threads are metric but using an imperial leadscrew I also dont use the thread dial but keep the halfnuts engaged.
It goes, half nuts disengaged, move to start of thread, engage half nuts, take first scratch pass, stop at end of thread, retract cross slide, do not disengage half nuts, reverse back to start, check its the correct thread, advance the cross slide for the first real cut, start the cut, stop at the end, retract the cross slide, reverse back to start, advance cross slide for next pass and so it goes.
The solid plinth instead of the top slide is to improve rigidity on my flexi 9x20

 

[woodchucker]

I will try that.
I have just been cranking the cross slide out one turn, hit reverse to return leaving the 1/2 nuts engaged, then advancing the compound like .005, then returning the X slide back to zero and taking a cut.

I thought that was the correct way.

well, that is one way.
I just roll the carriage back... I assume you don't have a dial?

 

[mksj]

well, that is one way.
I just roll the carriage back... I assume you don't have a dial?

Doesn't work for metric with an imperial leadscrew, as the threading dial registration is not the same. Using the compound is used more on smaller lathes, also depends on the thread cutter and the material. Using the cross slide there is a direct reading of thread depth vs. using the compound. CNC machines may use a combination of threading movements. If you use a dial or DRO for the registration of the stopping position in the thread relief, the stopping with the compound the position of the cutter changes as it is advanced, so the thread relief needs to be wider. Since I use an electronic stop, the position of the cutter needs to not change as the cutter is advanced. The method one uses suits the type of thread, material, machine and operator. Example below is a longer tool post with a M16 base thread I made for a forum member, factory post is on the left and the new post/threads with minimal relief on the right using O1 steel rod.

 

[brino]

compound vs cross slide is a religious type of argument. some do one, others do the other.

Nope!
It is pure science! (see * footnote below)

Both work,

That depends.........

Feeding with the compound at 29.5 degrees means that you are only cutting on the left-hand side of the tool.
On lightly built or worn and sloppy lathes, that can mean reduced cutting forces giving less flex and less chatter.

On my previous lathe I had to do that.
On my current lathe, I still had to do that......... until I got the gibs cleaned-up and adjusted properly.

Yesterday I cut threads for the first time in a while.
I used only the cross-slide and it went very well.

*footnote
Of course, there is also the aspect of "doing it the way you were taught".
Although you might have been taught on a very different machine than you use today......

Brian