Printable View
Hi Everyone,
This forum has been set up to serve as a support location for the ELS product.
Unlike the Yahoo E-Leadscrew group which deals with all different kinds of methods for controlling a lathe lead screw I'd like this forum to concentrate specifically on the ELS design and be the place were specific support questions and photos can be posted.
I won't be ignoring the E-Leadscrew group but I think this forum is a bit more user friendly.
Thanks
John Dammeyer
http://www.autoartisans.com/ELS/
Hi,
I want to build a backguage controller for my guillotine.
The back guage is currently controlled by a motor connected to a leadscrew and has backward and forward motion.
I basically want a controller whereby i key in the measurement i require and the back guage must move to the correct position.
The maximun travel of the backguage is 1020mm
any ideas
You bet that's possible. It's the next project on my do list for the ELS for my own shear and bender. I have already made up the sprocket hubs and cast one carrier block.
The attached photo shows what the guide assembly would look like. The motor would sit in the middle attached to both screws with chain and sprockets. For bending metal I'd include the K factor, thickness and bend depth. For shearing just the cut depth. The motor would move the fence to position.
The spindle sensor input will be used to calibrate the fence location although it may be possible to use stock ELS software and just set a measured position. Something like shearing a piece, measuring it and then entering that value into the ELS. At that point while power is applied it would remember where it is.
John
Brilliant,
I want to use it on a paper guillotine but it works the same way as in your application.
i had a look at my machine today and noticed it has a single lead screw in the centre and two slides on both sides of the leadscrew. The motor is 3 phase and connected via a small gearbox to the leadscrew. i have two buttons up front for backward and forward.
would I have to remove the current motor and gearbox? What else would I need to get the whole setup running?
Say i have a sheet that's 500mm in length and i want to cut different sizes out of it. Would I be able to enter 500mm first and just press (-) and the size i need? instead of calculating and entering measurements
My machine is about 25 years old and works 100%. Its a german product and built very accuratley. With a computer controlled back guage it would reduce my cutting labour time by 60%.
Comercially available systems cost about USD$5000.00 which is more than what the machine cost so I am seriously considering your product. However I want to get all the info I can before I buy it.
I would replace the motor and gear box with a Stepper Motor. It's difficult to say how large it needs to be. You might have to do some experiments by attaching a lever and hanging a weight to see how much torque is required to turn the screw. Or just take a chance on the motor.
The ELS can drive a stepper motor up to 3 amps. So you would need a power supply of about 24VDC to 45VDC. Ultimately some sort of switch for a Predefined position. It doesn't have to be HOME for 0.000.
As to how to use it, that's hard to say at the moment since I haven't written software for a backfence yet.
The only automated motion available is a move to HOME. (0.000" or 00.00mm) so if you could program in the current position (which isn't possible at the moment) you could then tell the ELS to take the Z axis to HOME.
Stay tuned. I do want to have something like this working soon. Meanwhile, start figuring out how to connect a size 23 or size 34 stepper motor.
What I have learnt from the other systems available.
One you install the setup you just move your back guage to the min and max positions and enter the measuremnts. This is stored in the system and will not change
You can load a full sheet into the machine by inputing the size of the sheet and work backward by minus the size you need.
Sound quite simple but guess its not when you building a standalone controller to do this
please keep me informed on ang progress
There's no guarantee that the unit won't be turned off. At that point, it's unknown exactly where the fence is. So on power up I would (on request from user) move the fence until it reached a home switch. At this point the system knows where the fence is because the operator has already calibrated the system that the home switch is at X.Quote:
Originally Posted by Bread_O
The operator has also told the system what the maximum and minimum distances are relative to X.
To me working backwards from the sheet size is odd but I can understand why a system might work that way. The cut off pieces are in front and haven't dropped down into a bin.
Seems more logical for most non-production line applications to ask for a specific size and then have the fence move to that location. That's because the size of the piece of metal picked as raw material is unknown or hard to measure accurately (to the nearest 0.001").
For fixed size paper products I can see why it's done the other way. No reason the software couldn't address both.
John
OTOH
Hello,
I know exactly what you're talking about - paper cutters. I worked at a shop when they bought a new expensive, really nice cutter.
It had an air table - little check-valve balls on the table surface every 5" or so that opened when pressed down by the paper. Anyways...
The ELS as an electronics kit would be well suited for this application.
It would ideally need different firmware unless you want to key in each distance (which you don't since you mentioned production time.)
What you want is a set of user "programs". Each program is a series of back-fence distances, advanced after each cut. Each program is a specific pattern of cuts to start with a standard parent sheet size and end up at whatever is needed.
I visited that shop a few years back and checked out the fence positioning motor setup. It looked like maybe some kind of DC or 3ph brushless motor and a separate rotary encoder off a timing belt from the single leadscrew. Motor size was surprisingly small.
Encoder is pretty important - there is some back-driving going on when jogging the lift of paper against the backstop. That machine would detect that and reposition in that case: increase distance then sneak up to the exact distance.
Another thing I remember is that sometimes it was useful to have the backfence push the paper out, but now that I think about it, that sounds a little weird.
-Matt
The backfence I'm building for my 3:1 metal brake/shear is going to be pretty crude I think. Two lengths of 10TPI acme all-thread with nylon nuts to reduce backlash. Each lead screw will sit under the guide rod and they will be connected with a chain which is driven inbetween the two with a stepper motor.
The fence brackets will use bronze oilite bearings although I should probably use linear bears or rails with cars. Attached pictures should give you the idea of what I'm trying to do.
However, work-work has been so busy lately I haven't found myself in the shop now for several months.
John
OK I'm very interested in this one. My question is;
Does the design have the ability to "map" the leadscrew? That is, can it add a correction factor for any given point along the leadscrew. I would like to be able to get ball-screw accuracy from all-thread rod.
Thanks,
Bob B.
Alas not. This would only be possible if there were an encoder or some sort of index pulse off the leadscrew too so the computer could keep track of where the lead screw is from a cold power up start. It doesn't. And then even mapping it would be difficult.Quote:
Originally Posted by 40fordcoupe
A more advanced unit would probably work better to have a linear encoder on the carriage and use the position as feedback. But the ELS isn't that powerful.
Sorry.
John
I would also like to make the back fence on my paper guillotine automated. At present it is hand operated and one turn of the handle moves it 10mm.
What I want it to do is add a stepper motor to move the leadscrew which is fairly simple but what about a controller? I see reference to an ELS, or is it easier to go the PC route, has anyone done this before?
Thanks Peter
Hi PeterQuote:
Originally Posted by peterb33
I have a pile of castings, the polished rod, bronze bushings and #35 chain and sprockets all ready to be assembled once I finish machining the castings. The goal was to put the ELS onto my 30" 3:1 roller/brake/shear automating the back fence for the shear.
I was also going to add things like K factor and bend radius etc. as parameters to the ELS so that the back fence could be set up to the brake for simple folds. Now granted there are so many variables for bending metal that ultimately one would have to test bend anyway but even just for 3" outside tab on 22g aluminium to have the fence go to pretty close for that initial trial bend would be so nice
But then in December 08 the 2010 Olympics came along and for the next year I was busy doing LED lighting projects (like the rings) and the machine shop took a back seat. Only today, for the first time in over two years have I cast something.
So the short answer is yes. The ELS can even do it now although there's no distinct home switch to automate things. On power up you'd have to move the fence to the zero position and zero the scale. After that you can key in a BEGIN position and press START. With the X axis disabled, the ELS will always stop and ask you to move the tool into the workpiece. At that point you'd shear what you wanted. Press the BEGIN button again and enter a new position, press OK. Press TURN and START and the fence moves to the next position.
It's kludgy but it would work. My initial tests with the ELS and my 3:1 tool will be done that way. Then I'll add support for a home switch which can have an offset attached to it so that when it's been found the axis is set to the correct distance from the fence. I'll have a Shear or Bend button pair instead of a Turn or Screw pair so the correct fence offset is used.
Sorry to be so wordy. I've been planning this for quite some time and really want to get it done. But I've been sidetracked into building a JGRO CNC router for pattern making and automating the drilling and milling all the holes in a box for the ELS.
John Dammeyer
Hi John,
Thanks for the reply and explanation of why there was a break, I wondered what happened and the olympics looked really great!
The guillotine works really well so it would make sense to add electronics rather than change it and I need to do a lot of repetive cutting which involves changing the settings manually. We all know how easy it is to misread dials under these conditions so what I was looking for was to step to the various sizes once these had been programmed.
It looks like your els will do this now from your explanation but adding the other features would be a bonus.
I plan to do the alterations soon so no desperate panic really, how many of the kits have been produced?
Peter
I currently have 12 kits available and 4 assembled units. However, I"m off to Greece for a holiday this week and won't be back until the 18th.
Since much of the brake/shear type operations include repetitive operations where a number of bends or cuts are made, it would make sense to add a list of say 8 or 10 XY positions that you could cycle through.
John
John,
Final question. Is it possible to add this list of that I could cycle through to the els as it stands now?
Think what I need is to get a unit and play with it or at least become familiar with the instructions.
Hope you enjoy your hols---sounds like you have earned it!
Thanks Peter
I've not given much thought on how I'd add that to the Lathe ELS. It would fundamentally change how it behaves. I'll ponder on it over holidays.
Thanks for the suggestion.
John