[SCzEngrgGroup]

Ray, any clue on a potential price point yet for the new ATC?


Nate
Fine Line Automation
Home - Fine Line Automation

Nate, Hasn't been set yet, but it will be in the same ballpark as the Tormach. Unfortunately, you really can't do a quality ATC for much less.

Regards,
Ray L.

[SCzEngrgGroup]

Ray, any clue on a potential price point yet for the new ATC?


Nate
Fine Line Automation
Home - Fine Line Automation

Nate, Hasn't been set yet, but it will be in the same ballpark as the Tormach. Unfortunately, you really can't do a quality ATC for much less.

Regards,
Ray L.

[SCzEngrgGroup]

Boy, was this one of those days.... Went out to make the rest of the new coupler parts. Halfway through the first one, the Y axis faulted, with an encoder error. I removed and re-seated the connectors at both ends of the encoder cable, but no change. So, I swapped all the cables between the X and Y servo drives, to isolate whether the problem was in the motor/encoder or drive. But, after the swap, it's worked perfectly for hours, so I have no clue what happened this AM. Weird...

Got the rest of the couplers done, and installed, and they work really nicely. Only problem is after just a few minutes of testing the little servo motor died - one of the windings opened up. Sadly, that is the ONLY motor for which I don't have a spare on-hand, so I may be down for few days until I can get another one in, unless I can manage to repair it. But, the couplers work really nicely - they center the tool to the coupler motor, which is exactly what I wanted - not only providing accurate, repeatable location, but also locking it in place

Two steps forward, one back....

Regards,
Ray L.

[mklotz70]

Ray....I'm right there with Air Gunner. I really look forward to updates in this thread!!

Are you familiar with Coil Springs Manufacturer - Stock & Custom - MRO & OEM | Century Spring Corp. centuryspring.com ? Tons of great info and options. My local hardware stores carry some of their stuff, so I've been able to find what I want online, then pick them up locally.

Get well soon,
Mike

[SCzEngrgGroup]

Now that the forum finally seems to be back almost to normal....

The last week has not been as productive as I'd hoped. I was sick for several days, then had out-of-town company for several more. I do now have the new transfer arm fork made, and today I re-made the lower end of the transfer arm drive, which includes a radial support bearing for the transfer arm shaft, re-located gear-motor to provide proper tension on the belt drive, and the encoder has been moved from the motor down to the belt drive, inside the (sealed) belt-drive housing. Backlash on the transfer arm is now very greatly reduced. In fact, it is considerably less than I expected.

Unfortunately, all the little changes end up rippling through other parts, so there are a few more parts I have to re-make, including the transfer arm shaft. I also have some changes to make to the lift drive, to incorporate the encoder into the thrust bearing housing.

I got the new 10X+ faster MCU boards last week, and it only took a few hours to port the firmware over to the new processor. Unfortunately, I now have to rip up and re-do part of the electronics, as the new MCU is 3.3V, while the old one was 5V. So, I have to remove all the level-shifters I had to add so the 5V MCU could talk to the 3.3V FPGA! But, the new processor will give me a lot more capability, so well worth the bother.

Here are a few quick pictures:

New Transfer Arm Fork:

Attachment 240970

Transfer Arm Encoder tucked away inside the belt drive housing:

Attachment 240972

New Transfer Arm Drive "Bottom End":

Attachment 240974

Also had a small problem with my machine today. I think I mentioned that about a week ago my Y axis servo threw an encoder fault. I swapped the X and Y axis drives, to narrow down whether the problem is really the encoder or the drive, and it's been working fine since. But today, the Y axis again threw an encoder fault. Since it's now happened on two different servo drives, clearly the encoder has a problem. Luckily, I have a Pulsar as well, so I stole the X axis motor and encoder from the Pulsar, and swapped it into the Y axis of the Pro, and had no more problems the rest of the day. Swapping motors only took about 20 minutes, so not a big deal. I'm not sure if it's possible/practical to replace just the encoder, as it's integrated into the motor. So, I may have to get a complete replacement motor.

Regards,
Ray L.

[engnerdan]

Also had a small problem with my machine today. I think I mentioned that about a week ago my Y axis servo threw an encoder fault. I swapped the X and Y axis drives, to narrow down whether the problem is really the encoder or the drive, and it's been working fine since. But today, the Y axis again threw an encoder fault. Since it's now happened on two different servo drives, clearly the encoder has a problem. Luckily, I have a Pulsar as well, so I stole the X axis motor and encoder from the Pulsar, and swapped it into the Y axis of the Pro, and had no more problems the rest of the day. Swapping motors only took about 20 minutes, so not a big deal. I'm not sure if it's possible/practical to replace just the encoder, as it's integrated into the motor. So, I may have to get a complete replacement motor.

Regards,
Ray L.

I have taken apart several servo motors in the past. While some use an custom PCB based encoder. The last couple I have opened all had an off the shelf optical encoder mounted under the rear cover. It should be nothing for you to do. Start by carefully taking the back cover off and see what is inside.

[SCzEngrgGroup]

I have taken apart several servo motors in the past. While some use an custom PCB based encoder. The last couple I have opened all had an off the shelf optical encoder mounted under the rear cover. It should be nothing for you to do. Start by carefully taking the back cover off and see what is inside.

Normally, that is exactly what I would do. But Novakon is sending me a replacement motor and encoder.

Regards,
Ray L.

[mklotz70]

.....so can you take apart the bad one when it gets replaced so we can see what's in it? I know you're busy, but I'm sure we're all curious.

I look at those beautiful parts you're making and get excited about what I can make with my Pro! Thanks!!

[SCzEngrgGroup]

.....so can you take apart the bad one when it gets replaced so we can see what's in it? I know you're busy, but I'm sure we're all curious.

I look at those beautiful parts you're making and get excited about what I can make with my Pro! Thanks!!

I did actually open it up, but didn't take any pictures - really not much to see. The cover comes off with four screws, and inside is - SURPRISE! - an optical encoder. Coolant had gotten inside, and the encoder was wet with condensation. I dried everything off and left it open for a day to dry out. I then put it on the Pulsar, and it seems to be working fine again. Oddly, the connectors are all IP67 rated (i.e. - waterproof), yet the housing itself was not even gasketed. At some point, I intend to take all of my covers off, and either add gaskets, or sealant, to ensure this does not happen again.

Regards,
Ray L.

[mklotz70]

I did actually open it up, but didn't take any pictures - really not much to see. The cover comes off with four screws, and inside is - SURPRISE! - an optical encoder. Coolant had gotten inside, and the encoder was wet with condensation. I dried everything off and left it open for a day to dry out. I then put it on the Pulsar, and it seems to be working fine again. Oddly, the connectors are all IP67 rated (i.e. - waterproof), yet the housing itself was not even gasketed. At some point, I intend to take all of my covers off, and either add gaskets, or sealant, to ensure this does not happen again.

Regards,
Ray L.

Thanks! Optical encoder....I get the picture
Maybe a wrap of silicone tape or good electrical tape will seal the cover well enough for now?

[SCzEngrgGroup]

This has been a couple of weeks filled with the "thrill of victory", as well as the "agony of defeat". I'm now running on the MUCH faster MCU, which has enabled me to greatly speed up the servo loop. I"m now running at 2 mSec (it was 10 mSec), and I'm confident I can easily run at 1 mSec. I've been able to simplify and speed up the servo code, and also made changes which further improve the positioning, and better deal with the "stiction" and backlash. The carousel is now working very nicely, and reliably, and it can be run as fast as I see any point in running it. The tool "lock" is also working nicely, and does a great job of pulling the tool receiver to exact final position, and holding it still as the tool is inserted and removed. I re-made several parts of the transfer arm drive, mounted the new high-resolution encoder on the output shaft, and got proper tension on the belt drive. I also made a second pass through the FPGA and made some minor improvement there, and the electronics as a whole have been working perfectly for some time now. I haven't even blown up a single motor H-bridge!

I was able to go through the entire toolchange sequence quite a few times over the last few days. though I didn't have a chance to capture a video. The *only* potential problem I see getting close enough alignment between the tool in the transfer arm and the tool receiver and spindle. Unlike "real" ATC toolholders, like ISO, CAT and BT, TTS is very unforgiving on alignment. the tool MUST be pretty well centered before it can be inserted. A little off-center, and it WILL cause jam. The tolerance is only about +/-0.05", which is not much. I REALLY wish I could do this with CAT30 instead of TTS....

The one fly in the ointment is the motor and gearbox I've been using for the transfer arm are simply not up to the task. There is too much backlash, and nothing I can do in software mitigates it adequately. This makes getting adequate alignment of the tool to the spindle extremely difficult. Today I swapped out the gearbox for the same one I use in the PDB, which only required a few very minor modifications to a couple of parts, and a simple mounting adaptor. This one has lower backlash, and also has the advantage of a very wide range of selectable gear ratios, and a very wide range of motor choices. However, even with this, I think I will also have to give up on my dream of being able to position the transfer arm based solely on encoder readings, and will instead have to provide a "hard stop" to set the final alignment to the tool receiver and the spindle. This is quite trivial on the carousel, a bit trickier on the spindle, but it still do-able. Unfortunately, I ruined my last spare timing pulley, trying to bore it out for the new gearbox, so I'm dead in the water for a few days until I can get a replacement in.

All in all, I'm pretty far behind where I'd hoped to be by now, but I see few potential obstacles beyond this point. I have a good feel for what remains to be done, and none of it appears terribly daunting, the worst of it being the problems with the transfer arm. So far, everything - hardware, electronics, software - is proving to be quite reliable, and behaving at least consistently. That at least gives me confidence there should be no major surprises down the road.

BTW - I don't know how many of you guys are signed up as "Novakon Demo Centers", but I signed up a while back, and I've been surprised at the number of contacts, and visitors, I've had. I've had, so far, four people come visit over the last few months. Most just want to look at the machines, and talk about the "Novakon experience", a few had specific operations they wanted to see demonstrated, ,so I setup a demo for them. Average visit has been on the order of 2 hours. Its actually been kinda fun, and the people I've met have all been very nice. I'm confident at least a couple of them will be buying machines. Seems like most of the interest is in the Pro, though one guy was looking at the Pulsar, mostly because he didn't have room for the Pro. Seems to me like a nice way to meet other potential Novakon owners, or just CNC geeks, in your area.

Regards,
Ray L.

[tmarks11]

BTW - I don't know how many of you guys are signed up as "Novakon Demo Centers", but I signed up a while back, and I've been surprised at the number of contacts, and visitors, I've had. I've had, so far, four people come visit over the last few months.

Since I was one of those people who visited Ray, I gotta say thanks for opening up your shop so I could see the equipment.

[bill south]

Ray;

With the importance of massive coolant flow, I would think Novakon would step up and offer a set of gaskets for the servos. Unless protected, the coolant will go everywhere and most often, where it shouldn't be!!!
Thoughts?
Bill

[SCzEngrgGroup]

Well, I was able to graft an encoder onto the motor of the new gearbox/motor assembly, and do some testing. Backlash is well within the acceptable range, and with a 100:1 gear ratio, it's more than fast enough, with more than enough torque. It is a bit noisier than I'd like, but there are ways that can be mitigated Positioning accuracy is very good, despite the relatively high friction that comes with the high gear ratio. Fortunately, it seems to be "dry" friction, rather than stiction, which is FAR more difficult to deal with. On the plus side,the friction acts as a built-in damper, which appears to make the servo tuning relatively non-critical. My one concern at this point is how much backlash is added by the belt drive. But, if need be, I can, with some difficulty, eliminate the belt drive. I also know from experience on the PDBs, that these gearboxes are VERY rugged, and do not show any measurable signs of wear, even after long, hard service.

Hopefully I'll have the new pulleys quickly, and be able to test the whole assembly, with belt drive.

Regards,
Ray L.

[SCzEngrgGroup]

Some forward progress - I found a pulley in my junk collection that I could modify to get the belt drive going.

But, that bit of good luck is balanced out by a bit of bad luck - there is too much backlash in the belt drive! It's a 3/8" wide 0.200" pitch XL belt. The belt is MORE than tight enough - enough so that it's not easy to assemble the drive. Yet there is MUCH more backlash than with the arm mounted directly to the gearbox. The belt actually moves within the pulleys, so either the teeth on the belt are too narrow, or the grooves on the pulleys are too wide. Either way, its not acceptable, so the belt drive will have to either use a different belt profile (like GT2), or be removed entirely, which is a bit of a complication.

Regards,
Ray L.

[SCzEngrgGroup]

It's now working, albeit with the sloppy belt drive. Ignoring the backlash, positioning is excellent, and, most of the time, good enough to work. With a small change (about 0.020") in one dimension, I can swap out the XL belts and pulleys for 3mm GT2 equivalents, which should eliminate the backlash in the belt drive, and I should then be all set. Back to the SDP-SI web site....

Regards,
Ray L.

[SCzEngrgGroup]

After a little tuning, I'm happy to say I'm completely satisfied with the servo performance on both the arm and carousel. With a little bit more damping on the carousel, and the belt/pulley backlash removed from the transfer arm drive, they will be basically done. Both reach position very quickly, and settle in under a second to within 1-2 encoder counts of correct position - more than good enough. Both drives are "stiff" enough I don't expect any significant issues when running with heavy tools.

Regards,
Ray L.

[chevalier]

Ray,
I have been following this thread for some time and really appreciate your explanation of the design stages. The development videos are great to watch too. I wish I had your electronics knowledge. Could it be adapted to retrofit other brands of machine? I am from Australia and have a Syil X7 (BT30 spindle, air draw bar) just crying out for a decent ATC. Indexing of the drive dogs (VSD on standard asynchronous motor) could be an issue, but I have seen a similar machine run the spindle at 50 RPM (next to zero torque) and drive the dog up to a mechanical stop. So, I would have no issues retrofitting a spindle orientation arrangement. Anyway, I understand if its only for Novakon machines. Looking forward to seeing the fully functioning video.

Thanks in advance
Greg

[SCzEngrgGroup]

Ray,
I have been following this thread for some time and really appreciate your explanation of the design stages. The development videos are great to watch too. I wish I had your electronics knowledge. Could it be adapted to retrofit other brands of machine? I am from Australia and have a Syil X7 (BT30 spindle, air draw bar) just crying out for a decent ATC. Indexing of the drive dogs (VSD on standard asynchronous motor) could be an issue, but I have seen a similar machine run the spindle at 50 RPM (next to zero torque) and drive the dog up to a mechanical stop. So, I would have no issues retrofitting a spindle orientation arrangement. Anyway, I understand if its only for Novakon machines. Looking forward to seeing the fully functioning video.

Thanks in advance
Greg

Greg,

The basic design was designed specifically so it would be easily adapted to almost any machine by changing just a few very simple parts. It was also designed so that it can easily support 30 taper tools rather than TTS. However, It won't be offered for anything but Novakons until the Novakon versions are in production and fully sorted out, which, realistically, will be late next year at best.

I should have the first full-function video in a few days, as soon as the new pulleys and belts show up. I could do one right now, but it's not very nice to look at, with the backlash on the arm.

Regards,
Ray L.

[MichaelHenry]

Greg,

The basic design was designed specifically so it would be easily adapted to almost any machine by changing just a few very simple parts. It was also designed so that it can easily support 30 taper tools rather than TTS. However, It won't be offered for anything but Novakons until the Novakon versions are in production and fully sorted out, which, realistically, will be late next year at best.

Ray, was that a typo or do you think it will really take 18 months before the Novakon version is in full production? Seems like you are pretty close right now.

Mike