Electronic Leadscrews?

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ctwo
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Re: Electronic Leadscrews?

Post by ctwo » Mon Apr 02, 2018 10:23 am

The main controller IC of this system seems to be an ATmega 1284P (used in some Arduino kits). It's interesting that to cut shape profiles there must be some level of 2D machine control, and threading is going to require a spindle encoder. They state it's not CNC as it's not a g-code interpreter, but aside from that the operation seems the same to me.

I'm sure you've seen Tubalcain's electronic lead screw that he featured years ago, and Stefan's electronic Z drive?

I have much of the same electronics in my powered rotary table system and have thought a lot about building a similar type of controller for my Bridgeport CNC so I would not have to boot up the PC and run a complicated CNC program - just simple dumb number control/display with a few knobs to make it move - and maybe up to 20 or 100 "moves" that it could remember and perform in sequence. Then I'd be tempted to make an input streaming g-code parser.

Oh, and I don't agree with all of their reply - maybe the display would be challenging, but otherwise it's just a smop to translate units, and then still display to the 3rd decimal just the same.
Standards are so important that everyone must have their own...
To measure is to know - Lord Kelvin
Disclaimer: I'm just a guy with a few machines...

John Hasler
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Re: Electronic Leadscrews?

Post by John Hasler » Mon Apr 02, 2018 10:45 am

ctwo writes:
> Oh, and I don't agree with all of their reply - maybe the display would be challenging,
> but otherwise it's just a smop to translate units, and then still display to the 3rd decimal just the same.

I agree. Units are not relevant to the control loop anyway.

p pfeiffer
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Re: Electronic Leadscrews?

Post by p pfeiffer » Sat Apr 28, 2018 9:28 am

Weston Bye has a great article on a "home made" threading device (electronic) that he worked up for his Sherline lathe. As far as I know, it was published in Digital machinist at Village Press. these are the same people with Home Shop Machinist. I got my copy in a book of his articles by Village Press. I think it's called the Mechatronist. There is a stepper motor to control the lead and some dialable counter that controls the lead. He admits it's not set up for metric threads, but it COULD be done. Weston is rather good at what I like to call "putting the cookies down on a shelf where I can reach them"!

pete
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Re: Electronic Leadscrews?

Post by pete » Sat Apr 28, 2018 6:57 pm

Hmmm, that's something I didn't know that it wasn't set up to do imperial thread pitches so thanks Will. Seems strangely lacking to not have a system capable of either. I'd have very little need for nor would I want a metric only system.

WJH
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Re: Electronic Leadscrews?

Post by WJH » Sat Apr 28, 2018 7:08 pm

pete wrote:Hmmm, that's something I didn't know that it wasn't set up to do imperial thread pitches so thanks Will. Seems strangely lacking to not have a system capable of either. I'd have very little need for nor would I want a metric only system.
I haven't seen his article on it, but was it done analog style? Using a microprocessor, imperial or metric would simply be a divison problem on one line of code.

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pete
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Re: Electronic Leadscrews?

Post by pete » Sat Apr 28, 2018 7:53 pm

My thought as well about the division problem since afaik today about every industrial cnc machine is using metric ball screws. Imperial parts are just oddball metric sized to get those imperial dimensions or there's a possible built in program that allows the direct conversion such as when threading. This system isn't full cnc of course but still???? Electronics wise I'm below zero on having any real knowledge so anything I think will be incorrect. Europe must still have loads of older North American built equipment so imperial thread pitches certainly aren't unknown there. Metric only seems very limiting to me. Besides my car the only metric I ever make use of are on 3 of my machine tools and I wouldn't be making replacement fastners for either. If it's tracking the spindle and leadscrew correctly then it should be capable of screw cutting as accurate as the leadscrew is. Seems to me with my less than complete knowledge the brain box just needs the ability of inputting the leadscrews pitch into it for imperial or metric then chosing the pitch. His system is set up sort of building block style and you can add one or two axis. With the 2 axis some limited part shaping can be done such as tapers, ball shapes etc. That's all programable apparently.

Like John mines a change gear and mine has what's called a semi norton gearbox with only 3 threading pitches and feeds available unless I start gear juggleing. I didn't buy it because it's threading capabilites were the best, I bought it because it was the lightest (imperial) machine I could find that had the rest of the features I was looking for. ELS at a sane price would vastly improve what I have and where it's lacking. I have too much of the imperial taps and dies and am happy enough with imperial that switching over to only metric wouldn't be cost effective at all.

Magicniner
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Re: Electronic Leadscrews?

Post by Magicniner » Tue May 08, 2018 2:23 am

Will's 2882 wrote:
Mon Apr 02, 2018 9:44 am
I sent a request about getting a unit that would cut in inches.
1" = 25.4mm
Armed with this revolutionary information, and possibly a calculator, you can cut imperial threads on a metric system which allows dimensions set in .001mm increments

Magicniner
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Re: Electronic Leadscrews?

Post by Magicniner » Tue May 08, 2018 2:25 am

John Hasler wrote:
Sat Mar 31, 2018 8:07 pm
I can't see it as most of the way to CNC, though.
You're buying and fitting steppers, drivers, PSU, shaft encoders and a controller................

Harrzack
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Re: Electronic Leadscrews?

Post by Harrzack » Thu Aug 01, 2019 4:23 pm

Greetings!

This thread is a bit old - but I thought I'd throw in a little update. I have the latest version of the Rocketronics Electronic Lead Screw (ELS3) on my Little Machine Shop LMS 3536 (Seig SC4) lathe. Once installed - it does work very very well! And it is NOT a replacement for CNC. It is a (once you learn it) more accurate and efficient way to do manual turning.

Here is a link to another builders work - VERY well done and documented: http://bit.ly/2Tmhk2H Not a commercial unit - but he does give plenty of details.

With the carriage controlled by steppers & software, you get very accurate positioning, and for example - if you are turning to a shoulder, it ALWAYS stops at the same point making a clean shoulder automatic! Thread cutting of ANY pitch is just a dial setting away - but have not tried the yet. There are some good you tube vids of this working.

Currently my biggest prob is that the maker does not wish to REALLY sell to US customers (much red tape) and so the manual has not been translated to English yet. I did put the German PDF thru Google translate - but it is still hard to decipher.

If you are a skilled machinist with years of practice - something like this would prob be not for you. I think the software control adds some accuracy and repeatably that a hobby machinist may not have the time-on-machine to acquire.

I have some pix of my install if anybody is interested...

=Alan R.

pete
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Joined: Tue Feb 10, 2009 6:04 am

Re: Electronic Leadscrews?

Post by pete » Thu Aug 01, 2019 6:04 pm

Many thanks for the additional information Alan.

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