Clough42 ELS on PM1130V

[javaduke]

I've been lurking here for quite a while but decided to make a post (and ask for a suggestion too). Just a month ago I got my PM1130V lathe and decided to build an ELS for it, because the space in my garage is tight and changing gears each time would be tricky. Here are some pictures of my setup:

Oddly enough, everything worked as it should right away - well, at least, the electronics part. The issue I'm having right now is that the gear ratio from the servo to the shaft is 1:1 - which is definitely not enough. Since the machine also has an internal gearbox, my plan is to have 1:3 ratio to the shaft and leave the internal gearbox at the C setting which will give me a total of 1:6 reduction. The question is where can I buy the correct gear? It has to be metric, 14mm bore, 5mm keyway, module 1.5 and 60 tooth count. My google fu has failed me again, I cannot find anything like this, at least not for a reasonable price.

 

[ivel03]

Woah - that's a really neat idea to mount the stepper motor at a right angle like that. I've mounted mine above the gearbox input shaft with the shaft end towards the lathe. It is belt driven and i will have to drill a hole in the end of the cover to get it to fit on there. Your solution is brilliant eliminating the need to drill that hole. What stepper motor are you using?

Back to the gears - Maybe you can find something here that will work:

1:2/1:3 Metal Motor Bevel Gears 1.5-3 Modulus 15-54Tooth 90° Pairing 45# Steel | eBay

Find many great new & used options and get the best deals for 1:2/1:3 Metal Motor Bevel Gears 1.5-3 Modulus 15-54Tooth 90° Pairing 45# Steel at the best online prices at eBay! Free shipping for many products!

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Bevel Gear 1 /1.5 / 2 / 2.5 / 3 / 4 / 5 Modulus Various Number Of Teeth Choose | eBay

Find many great new & used options and get the best deals for Bevel Gear 1 /1.5 / 2 / 2.5 / 3 / 4 / 5 Modulus Various Number Of Teeth Choose at the best online prices at eBay! Free shipping for many products!

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This one might have the correct ones without modifications needed:

Steel Bevel Gear Ratio 1:3 Select Module 1, 1.5, 2 and 15, 45 Teeth | eBay

Find many great new & used options and get the best deals for Steel Bevel Gear Ratio 1:3 Select Module 1, 1.5, 2 and 15, 45 Teeth at the best online prices at eBay! Free shipping for many products!

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It'll take about a month to get any of those from my experience.

 

[javaduke]

I'm using the iSV57T-180 integrated servo that James recommended: https://www.omc-stepperonline.com/s...-20-50vdc-brushless-dc-servo-motor-isv57t-180
I didn't have any issues with it though, apparently they have upgraded the software and the documentation, and programming the servo really took 3 minutes. All I had to do is to change the microsteps param from 4000 to 1000.
Unfortunately with 1:1 ratio it doesn't work at all, it barely spins the leadscrew and after a short while it just stalls and the alarm LED is blinking, indicating the overload. I ordered the gears you linked below, it says I should get them by May 12th, lol But thank you anyway, I guess I'll have to find a new hobby to keep myself busy for the next two months )))

 

[javaduke]

Here's the most recent picture, with the lathe side cover in place and the electronics box mounted on the side of the stand (it is actually held in place by magnets, so that I can reposition it if needed).

 

[ivel03]

@javaduke - how did the bevel gears work out? Any pics of the finished product?

 

[markba633csi]

I guess you will have to change the motor mount (but hopefully not the motor) ; a larger gear will move the motor towards the rear
You can't increase the motor voltage or drive current? I presume you've already looked into that..

 

[javaduke]

@javaduke - how did the bevel gears work out? Any pics of the finished product?

I gave up on bevel gears and ended up using pulleys. I was able to squish the servo right between the casting and the lathe motor, there's just enough room there and it's very snug.
1:3 pulley ratio plus 1:2 gearbox setting seem to work just fine, but I'm going to try 1:5 pulleys and see if it works better. I'm also going to add a tension arm and bearing.

 

[WobblyHand]

How do you determine the correct belt length when you have unequal pulley sizes?

 

[javaduke]

There are pulleys calculators out there online, but I cheated, I just took a length of thread, wrapped it around the pulleys, measured the length, and knowing the tooth pitch I figured out what belt I needed. And, of course, after I make the tension arm, I will have a bit more wiggle room there.

 

[WobblyHand]

There are pulleys calculators out there online, but I cheated, I just took a length of thread, wrapped it around the pulleys, measured the length, and knowing the tooth pitch I figured out what belt I needed. And, of course, after I make the tension arm, I will have a bit more wiggle room there.

Sometimes the simplest solutions are best!