# Screwcutting Vid



## Bogstandard (Jan 12, 2008)

On my usual troll thru u-tube I came across this little vid.
It is totally boring, but if you have never tried screwcutting (and we have talked about this before) this shows it is really not difficult to do, and saves a lot of time and money for those one offs that you would go out and buy a die for and only ever use the once.



[youtube=425,350]0q_q53wsyHU&rel[/youtube]

Plus everything is concentric, not always possible when using a die.

Maybe we can have a bit of follow up on this for those who haven't got this under their belt yet. It is definitely worth trying.

John


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## jgarrett (Jan 12, 2008)

Traverse speed is a little too fast for me....Would use about half that speed...I learned to thread on a Maximat 5 which had no way to slow the feed down so I had to turn the spindle by hand. I was threading camera adapters. Now that I have a Emco V10 threading is a breeze.
The best way for someone who is learning is to just wade in a give it try with some scrap. Threading can be fun and rewarding.
Julian G.


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## Brass_Machine (Jan 12, 2008)

I have yet to give it a go. After I get some other stuff done I am going to try to thread on my lathe.

Eric


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## rake60 (Jan 12, 2008)

That slow tearing of metal is exactly how threads were cut by a single point tool
in 1920. Everything needed to be hand fit and threads were often filed to fit by hand.
It works, but if you want clean threads that don't require a file to finish them a higher 
surface speed will give you that. My own threading on soft material looks like this:
[youtube=425,350]pAwy6CUnzJ8[/youtube]

It's like learning to dive. Start out slow! As your confidence in the machine and your
own skills improve, work up to a speed that will give you the best finish that you are
capable of working to. 

My method has been publically called "insanity" 
It all boils down to what *YOU* feel safe and comfortable with.

Rick


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## Powder keg (Jan 12, 2008)

We thread that fast at work. Sometimes slower. Some of our shafts don't have a thread relief on them. You just pull out when you get to the end. (No jokes:O) I think they look better that way? I have a great thread chart I'll scan and post. It tells you how much infead you need for a certian pitch thread. You just stick a indicator against the cross slice and dial in that amount. (Not all at ounce:O) Marv has a program that does the same thing, I think?

Later, Wes


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## S_J_H (Jan 19, 2008)

And then there is cnc threading. ;D
I cut this thread at 500rpm on the cnc bench lathe I built, It was an early test of the machines threading capability






http://i109.photobucket.com/player.swf?file=http://vid109.photobucket.com/albums/n48/S_J_H/cnc%20bench%20lathe/cncthreading-1.flv
Steve


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## Powder keg (Jan 19, 2008)

Great job on your CNC. I can't wait till I can get started on my mill. 

Wes


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## Brass_Machine (Jan 19, 2008)

S_J_H, I am so gonna build one of those.

Eric


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## BobWarfield (Jan 19, 2008)

SJH, nice video!

You didn't mention what the material was, steel?

Seems like you could cut with a lot more rpm, at least 1000, no?

A faster speed might make for an even more interesting video.

Best,

BW


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## S_J_H (Jan 19, 2008)

Bob, it was 12l14 steel. I'll take a vid of it cutting threads at 1000rpm rpm in the near future. 
The only problem with threading and Mach3 is I don't think you can stop and check the fit and restart. So sometimes manually threading would be a better choice. 

Since I built the machine I honestly have used it very little. I have been rebuilding a S/B 9" for the last few months. That is finally finished as of this weekend so I can play with the cnc lathe a little now.

This has to be one of the best featured forums I have ever seen!
Steve


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## rake60 (Jan 19, 2008)

Now that's the way to cut threads. 

The Mazak I run for a paycheck will cut a thread right up to a hard shoulder.
I find it very difficult to watch that first pass. 

Nice set up you have there Steve!

Rick


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## jgarrett (Jan 20, 2008)

S_J_H, Do you have a picture of the bit used to cut threads that close to a shoulder???? I saw the other post asking how to thread to a shoulder but I am interested in seeing the tool required to do that. Could not download the vid. because I am on dial up.
Thanks,
Julian G.


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## S_J_H (Jan 20, 2008)

Thanks Rake!

Julian, I just used a 3$ cheap brazed carbide bit in that vid. Style ER.
You can get them cheap at Enco-
http://www.use-enco.com/CGI/INPDFF?PMPAGE=154&PMITEM=383-6302

Steve


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