electronic lead screw

The z axis moves rather than the tool. Likewise, the x axis will move taking the place of a conventional cross feed. The y axis wouldn't normally move but it could be used to access other tools. The primary reason for doing this is to allow CNC turning with a piece of equipment I already have. The only requirement is to remember that because the work is moving rather than the tool, the G code is reversed. If drilling is required, drills can be mounted vertically on the table, ditto with boring bars.

I'm not sure of the origin of the holes in 1-2-3 blocks. I tried digging into the history of them but was unable to find any information. Like a lot of tools we have, they sprung from the necessity by a machinist and became commercialized. The blocks that Tom Lipton, Ox Tools, made are a superior design.

I don't think that using the ELS will cause any more wear other than the fact that I would use it more. I haven't used the power feed much in the past, largely because it was such a pain to be changing from feeding to threading and back. Now that it is just the push of a button, I'll be more inclined to do so. My plan is to cut power to my driver unless I plan to use the ELS which will stop the lead screw rotating when not in use. This will cut down on gear case wear.

Re: the auto release, there is a discussion in post #2 in this thread. https://www.hobby-machinist.com/thr...ops-or-disengage-mechanism.79084/#post-675769
I decided to use a mechanism similar to a firearm or crossbow trigger rather than a simple mechanical action. The seer is released by a solenoid (the rectangular box) and an extension spring will pull rod to the left and in turn, pull the pin on the half nut lever to release the half nut. The rod is slotted to allow the half nuts to be disengaged manually. Engaging the half nuts will cock the mechanism. The solenoid will be activated by a microswitch or possibly an optical or Hall effect sensor.

Unfortunately, as Clough as discovered, there is no easy way to use the ELS to trigger the mechanism. His design has the encoder adding counts whenever the spindle is turning, performing an occasional subtraction to avoid overflow. Using the ELS to stop z axis movement would require keeping the half nut engaged all the time. Otherwise, positional information will be lost. I think it is possible to keep track of the total number of counts but it may require some sort of homing circuitry for the carriage. We'll have to see what Clough comes up with.

Actually, it should be possible to keep the half nuts engaged at all times and use the enable and steering circuitry on the driver to to disengage and reverse the lead screw motor.
 
The z axis moves rather than the tool. Likewise, the x axis will move taking the place of a conventional cross feed. The y axis wouldn't normally move but it could be used to access other tools. The primary reason for doing this is to allow CNC turning with a piece of equipment I already have. The only requirement is to remember that because the work is moving rather than the tool, the G code is reversed. If drilling is required, drills can be mounted vertically on the table, ditto with boring bars.

I'm not sure of the origin of the holes in 1-2-3 blocks. I tried digging into the history of them but was unable to find any information. Like a lot of tools we have, they sprung from the necessity by a machinist and became commercialized. The blocks that Tom Lipton, Ox Tools, made are a superior design.

I don't think that using the ELS will cause any more wear other than the fact that I would use it more. I haven't used the power feed much in the past, largely because it was such a pain to be changing from feeding to threading and back. Now that it is just the push of a button, I'll be more inclined to do so. My plan is to cut power to my driver unless I plan to use the ELS which will stop the lead screw rotating when not in use. This will cut down on gear case wear.

Re: the auto release, there is a discussion in post #2 in this thread. https://www.hobby-machinist.com/thr...ops-or-disengage-mechanism.79084/#post-675769
I decided to use a mechanism similar to a firearm or crossbow trigger rather than a simple mechanical action. The seer is released by a solenoid (the rectangular box) and an extension spring will pull rod to the left and in turn, pull the pin on the half nut lever to release the half nut. The rod is slotted to allow the half nuts to be disengaged manually. Engaging the half nuts will cock the mechanism. The solenoid will be activated by a microswitch or possibly an optical or Hall effect sensor.

Unfortunately, as Clough as discovered, there is no easy way to use the ELS to trigger the mechanism. His design has the encoder adding counts whenever the spindle is turning, performing an occasional subtraction to avoid overflow. Using the ELS to stop z axis movement would require keeping the half nut engaged all the time. Otherwise, positional information will be lost. I think it is possible to keep track of the total number of counts but it may require some sort of homing circuitry for the carriage. We'll have to see what Clough comes up with.

Actually, it should be possible to keep the half nuts engaged at all times and use the enable and steering circuitry on the driver to to disengage and reverse the lead screw motor.
So when the LS is reversing, whats the Chuck/encoder doing? They would have to stay in sync to retain the 'start position' (better wording needed here, but hard to express!) Of the thread.
I am considering the Russian ELS
By Oleg A., as it has cross slide X axis drive, whole threading process is automatic.
See https://www.cnczone.com/forums/arduino/328770-cnc-posts.html
Thanks for the auto release link! And hint re Ox tools too.
Could u clarify re ''G-codes reversed'', maybe an example, if thats OK?
 
I assume you are referring to my last paragraph or two. I haven't thought this through as yet but the idea is that it should be possible to know what the spindle history and the lead screw history are by virtue of their encoders. When reaching the end of a threading pass, the stepper driver would be disabled stopping the lead screw. The spindle encoder count would continue to accumulate. The cutter would be pulled out and the stepper driver reversed, reversing the lead screw and counting down the stepper encoder. Meanwhile the stepper continues to accrue counts. when the carriage has moved far enough to the right, it would be stopped, presumably by a user command. The cutter would be positioned for the next cut. Now the stepper encoder is way behind on counts so the controller would have to do an adjustment to resynchronize the counters, based on the count ratio for the required thread pitch. This would be analogous to using the thread dial to resynchronize.

It seems kind of messy but something similar must be happening with the the Russian ELS, the German ELS, and with a CNC lathe. It's all a matter of accounting. The spindle is in effect controlling all the motion based on a preset program entered by the user.

Re: the G code question, I sent a PM
 
Bob, am Having trouble when on the pm page, problem is cant find how to get back here to this point on my mobile ph., or even with the PC.
 
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Bob, am Having trouble when on the pm page, problem is cant find how to get back here to this point on my mobile ph., or even with the PC.
You should have an envelope icon in the upper right corner of the page. If you click on that, it will open the conversations list. Select the one you want to view.
 
Bob, am Having trouble when on the pm page, problem is cant find how to get back here to this point on my mobile ph., or even with the PC.
On my phone, the icon is to the right of my personal icon.
 
Sorry should clarify, by back here I mean back to main forum after viewing PM's.
 
[QUOTE="RJSakowski
[/QUOTE]
Am fiddling with various settings, on cloughs control panel, does the power button on the 'led&key' board do anything on yours?
(All other buttons are working here).
 
re: navigating HM Apparently, you figured it out. I don't use my phone for viewing HM for the most part. My thumbs are all thumbs when it comes to typing.
 
The power button isn't activated. I believe tha Clough had said so. The settings button just brings up a "no settings" message.

It is interesting that the led key board allows control of the individual segments of the display. The to extra buttons could allow a large number of options. If the Power button was used to scroll through a menu and the settings button and/or the up down buttons used to change settings in the various menu items, it would be possible to use this display to set limit positions or trigger a reversal of the lead screw.

One possible scenario would be thread to a point and stop the lead screw. the operator pushing the settings button after retracting the cutter would switch the direction of the lead screw, moving the carriage for another pass and there it would stop. Pushing the button after setting the cutter would start the next pass. But again, there is going to have to be some additional computation done in the controller to keep track of the synchronization.
 
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