[4]

New PM-25MV Mill

[3]
[10] Like what you see?
Click here to donate to this forum and upgrade your account!

macardoso

H-M Supporter - Silver Member
H-M Supporter - Silver Member ($10)
Joined
Mar 26, 2018
Messages
297
Thank you! Currently the stock 1 HP BLDC motor

I'm impressed! You can certainly hear it bog down at the start of the cut, but it really moves some material. I'm excited to see how your ATC turns out! We might have to exchange notes!
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
I'm impressed! You can certainly hear it bog down at the start of the cut, but it really moves some material. I'm excited to see how your ATC turns out! We might have to exchange notes!
I appreciate that! The spindle motor does seem very slow to react when a load is applied, and I noticed that even before it was CNCd. Taking manual cuts with the motor pulleyed in its stock configuration, it would still take a second to ramp up the torque. I am hoping that the new motor solves those problems. I know that the currently spindle isn't straining with those light cuts though. Most of them were under .25 WOC, .05 DOC, and 35 IPM which is only .4375 in^3/min. It managed 1.25" WOC, .05" DOC, at 52 IPM which is 3.1875 in^3/min which is 7x the cut. After that the belt slipped, but the motor was still pushing.

Hopefully I can get the ATC up and running soon! Besides the tool fingers (3 parts for each of the 10 fingers...) I only have 6 more parts to make. We should exchange notes for sure. I will have a few questions about the programming, since I think you mentioned you already did that part.
 

macardoso

H-M Supporter - Silver Member
H-M Supporter - Silver Member ($10)
Joined
Mar 26, 2018
Messages
297
I will have a few questions about the programming, since I think you mentioned you already did that part.

I think the motor bogging down has more to do with the control electronics than the motor horsepower. It takes the slow control loops in the stock motor electronics a bit of time to "catch up" when a load is applied. Not sure there is much to be done about that.

The software to control the ATC isn't too bad. Are you running Mach 3?
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
I think the motor bogging down has more to do with the control electronics than the motor horsepower. It takes the slow control loops in the stock motor electronics a bit of time to "catch up" when a load is applied. Not sure there is much to be done about that.

The software to control the ATC isn't too bad. Are you running Mach 3?
I agree completely. The new spindle motor is a servo, so in theory it should catch up faster.

I am using linuxcnc.
 

macardoso

H-M Supporter - Silver Member
H-M Supporter - Silver Member ($10)
Joined
Mar 26, 2018
Messages
297
I am using linuxcnc.
I did my ATC with Mach, so the configuration won't match, but the concepts should be the same. I wish there was a well documented, feature filled, and stable machine control software for us hobbyists.
 

GunsOfNavarone

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jun 26, 2018
Messages
275
Man! The last few post here i had to read twice each...thought I was reading typo's, come to find out I'm just stupid on this subject. That video, I could watch that for a very long time....mesmerizing...
Well, I will definitely be hitting you up for some help when the time comes, great work there brother!
 

phazertwo

Active Member
Registered
Joined
Dec 31, 2016
Messages
202
I recorded the machine making a few cuts. Most of them are pretty light, but it should give you an idea how it is running.

Just watched your video. Good looking stuff you got going on there. Who's cutter is that 5/8 2 insert endmill?

Have you tried turning up your non engaged speed when running an adaptive tool path? It almost looks like you're cutting faster than the linking moves.

PZ
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
Just watched your video. Good looking stuff you got going on there. Who's cutter is that 5/8 2 insert endmill?

Have you tried turning up your non engaged speed when running an adaptive tool path? It almost looks like you're cutting faster than the linking moves.

PZ
I usually bump it up to 80-100, but it looks like for that one, I left it at 35, the same as the cutting feed rate. I agree though, it does look like it is cutting faster.

The end mill is made by Zenit and uses ACMT inserts. I think I have ACGT inserts in it at the moment. I got a deal on ebay for a .375" single flute, a .5" single flute, a .625" 2 flute, and a .75" 3 flute, plus 40ish inserts for it for $50.
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
I got around to working up a mist coolant system out of an older RO filter I had around from fish tanks. I only needed a few extra parts to get it going. That included 1 connector, a block to mount everything to, 2 pressure regulators, a solenoid valve, a needle valve, and a locline kit from ebay.

It works the same as any other fogless mister where there is pressure on the air line and the coolant line, then they come together in a block with a needle valve on the coolant line. I adjust the pressure on the two independently, then adjust the needle valve until I get a decent amount of coolant in the stream without fog. The machine will control the coolant using the solenoid valve, and the locline will let me redirect it anywhere I want.

The coolant tank is one of the filter bodies and I put a piece of copper pipe on the output line with an aluminum adapter. This way, the input puts pressure on the air on top, which forces the coolant down, through the copper pipe, and out to the machine.

I haen't had a chance to test it on the machine, but off the machine and using water, I was able to get good coolant flow with very little sputtering and very little fog.

Here are all the extra parts I had from taking apart the RO filter along with the 2 pressure regulators.


Here is the adaptor that fits the copper pipe into the filter body.


Here it was with the copper pipe forced through it.


Then I made this little block out of aluminum and that connector you see on top for the air line. This screws into an existing hole whos original function I have yet to determine...


At the very least, this means I will not need to sit there with the air gun spraying out at is interpolates holes. Hopefully, with coolant it will be able to run reliably without me keeping an eye on it.
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
Looks good, and way nicer than my setup! Again, good work!

PZ
I appreciate it! Funny that you mention that, I was actually mimicking your mist system, and your post where you said

"I like to pretend I'm a tough guy, but let me tell you... I giggled like a 3rd grade school girl at a sleep over... for the ENTIRE TIME it was cutting. Watching the mill chew up that material with out me needing to do ANYTHING but watch, freakin' amazing. Mist coolant is THE BOMB! "

is what made me say "Ef it, I need to get a mister set up!"
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
I ran into a bit of snag with the ATC. I had a plan to machine the fingers that would minimize set up time and hopefully get me an accurate part. The critical part is the thickness of the area that needs to fit into the groove of the tool holder, and the distance from the top of the finger, to the top of the groove. It needs to be repeatable so that when the head lowers down to grab the tool, it can go to the same position each time and have the spindle face contact the tool holder shoulder.

The plan was:
1. Cut the 2"x.25" stock to length in the band saw.
2. Use a simple program to drill the 2 .25" holes in the mill while leaving extra space for error.
3. Make a fixture to hold them 2 at a time using the .25" holes to locate them and 2 screws to hold them down.
4. Face the fixture and use that height as the zero reference.
5. Machine the fingers 2 at a time.

Well something didn't work.

I designed the holders to have fingers that are .085" thick to fit into the .09" grooves on a TTS holder and leave a little room for error. I ran the first two, and that thickness came to .103 with a .013" tab left on the bottom of the holders. I measured the bare stock at .252 in most places and .255 at the worst area. I adjusted the zero height for the Z to bring it down .013" (.013" + .005" = the .018" they were over). Ran the next 2, and this time, they came out to .065". Weird, adjusting the height down .013" changed it .038". I tried adjusting the zero again to bring it up .02" and the next 2 came to .059".

So something is wrong with the Z axis losing steps somehow. I think it could be the motor struggling some places and losing steps when the head rapids up. It could also be something with the computer, but I would think if it was a latency issue, the X and Y would have problems too, since they move way more than the head does. It could also be that the ballscrew end supports are loosening up, the coupler to the motor, or maybe some stickiness in the ways. I will need to isolate this issue before I try again to make the fingers. Luckily, I ordered enough stock to make 24 fingers, and I only need 10.

I think finally putting the big 1000 oz in motor I have waiting on the Z will fix any issues with a lack of torque, and I need the current motor to rotate the tool changer, so that may be the next project. I need to make an adaptor plate and open up the coupler from .25" to .5".

The new spindle motor needs 240 volts (I got the go ahead to steal the line that runs to the hot tub) so it might make sense to plan to replace the 2 motors at the same time so I only need to deal with the wiring and such one time.

Here is the fixture.


The drilled finger blanks.


Mounted in the fixture.


After machining. These aint gon work.


I keep getting ahead of myself and forgetting about other stuff that really needs to be done before I should be working on the ATC. This includes:
1. Way oilers and ballscrew greases. I don't think I will get an automatic unit, but I would like to plumb everything so I can get to it easily to add the oil.
2. X and Y motor covers. I have some plans made up for these, hopefully keeping the chips out of the motor coupling and the ballscrew bearings.
3. Straighten ballscrews, remachine the ends square, make new spacers, and machine the mating surfaces. I have some ideas for getting the ballscrews working a little better. I also have some cheap linear scales I could try ballscrew error mapping with after.
4. New electronics enclosure. I am out of room in my current box, and I need to add more. I need to add the stepper driver for the ATC, the servo drive for the new spindle motor, another power line to get the 240 VAC to the servo drive, some connectors and fans. In NC summers, it can get hard to keep the electronics cool. Right now I have the door off completely and a box fan blowing straight at it. This isn't ideal since it will blow chips right into the electronics if the chips escape.
5. I need to finish making all my tool holders.

So there is a lot to be done to say the least. I am not completely sure at what point I will throw in the hat and say that's enough, but each improvement makes the machine run better and I am enjoying that so I will keep improving.
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
More parts, more progress, more problems!

I have been itching for some of those Mitee Bites Talon grips since I saw them on NYCCNC and how they securely hold the part using only .06". Unfortunately, for 2 jaws and 4 grips, it is about $200. They are relatively simple parts, so I made some. The jaws were very easy, made from aluminum and should last a very long time with the use my machine sees. The grips are scrap yard mystery steel, probably 1018 or A36. It machined nicely and didn't warp at all when I cut it down to size, so that makes me think hot roll. I started with 7 clamp blanks, then lost once since I drilled the center hole off center, and then one more was pulled from the jaws and marred up when I was cutting them to length. I ended up with 5 grips. I have not had a chance to test them yet, but I see no reason they won't work.

I made a manifold to distribute the compressed air to the machine. It takes 90 PSI from the compressor and connects to the 4 pneumatic systems the machine has (or will have) which are the mister, the power draw bar, an air gun, and ATC (when that is done...). Each line will have regulators and solenoids down stream to control the air.

I made the new mounting plate for the Nema 34 motor for the Z axis. Fusion has been being a little bit weird since the last update (as is always the case with Fusion) and has been giving me inconsistent heights with 3D adaptives. It doesn't make a lot of sense to me, since it will take a cut lighter than its maximum step down and leave extra material that it doesn't come back to cut. This is with stock to leave set to 0 and "machine shallow areas" checked. Anywho, the 2 contour for the motor face was at the right height, but the adaptive was about .02" too shallow. It should still work, but its not a good look and isn't ideal. I don't think that dimension is critical though, so I won't worry about it. I just need to either make a new coupler, or open up the current one from 1/4" to 1/2". I am not sure if it will fit, so a new one might be needed. Then I can wire it up, give it the full 7 amps the drive can handle, and the head should be zipping along.

The enclosure has had some milage put on it, and even with the back ATC section still open, and only 1 door, it catches most of the chips. I filled a 20 gallon storage container with chips contained in the enclosure, and in that time, the chips that escaped were maybe 3 inches deep in a 5 gallon bucked. If I can just figure out the door mounting, and then mount the rear panel, it should contain nearly all the mess.

I know I have mentioned a new spindle motor a few times, but I left out the details until everything was squared away. Another member here offered me a screaming deal on a servo motor and I just couldn't pass it up. I don't know if that person is ok with me crediting him for it, so for now I won't say who it was. The details were worked out and the new motor and drive are scheduled to be delivered tomorrow. The motor is a 2 HP 6000 RPM AC synchronous servo with a matching drive. The motor checked off all my boxes and then some (I wanted at least 1.5 HP, 5000 RPM, under 20 lbs, and fits on my machine). I plan to step up the spindle speed again, likely to 7500 or so. I plan to use the current pulley arrangement to see how the spindle responds to higher RPMs. With the current arrangement and faster motor, the spindle will get up to 13,200 RPM. My bearings are rated for 13,000 and 17,000 RPMs, but I don't think the spindle is nearly well made enough to handle that without excessive vibration. I would like to get it to 10,000, and maybe some balancing can make that possible. As a side note, its insane the difference in documentation between the cheaper hobby stuff and the industrial stuff. The hobby stuff comes with one 4"x4" sheet if you are lucky telling you basic dimensions and wiring. Or if you are unlucky, you can't get any information at all about the motor has a 100 page manual detailing every aspect of the motor including wiring, duty cycles, torque curves, etc. I have never used real equipment like this before so this was surprising to me. I already have the mounting plate designed and once I verify the motors dimensions, it I just need to make the one plate, wire everything, and figure out how to program and control it.

Since the new spindle motor is a servo, it can be run in both velocity and positioning mode. This opens up a number of new possibilities such as:
1. Rigid tapping
2. Indexing during tool changes
3. Holding position for using lathe tools with ATC
4. Indexing and holding for broaching corners

It would be pretty cool to be able to get the machine to hold a lathe tool in the spindle, cut a part using a lathe attachment, then use the ATC to switch to a drill or end mill and cut without me needing to do anything. I may need to add a brake to the spindle to keep it held strong if I want to make this work. But I couldn't be more excited for this thing and the things it may allow me to do. At the very least, 2 HP and 6000 RPM should let me remove a lot of material very quickly.

I also tore the Y axis way cover. When the table is close to the column, the way cover bunches up and gets caught between the vise and the Z axis way covers. I guess the rubbing wore a hole, and at some point that hole got snagged and now there is a big jagged gash in the cover. I would like to replace it either with accordion ways like the Z axis uses, or maybe some sheet metal or machined aluminum V covers.

Have some pictures!

Here are the jaws and grips. I don't have the correct screws yet, but they just need 10x32 countersink (what are the ones with an angled head called?) screws.


Pneumatic manifold/distributer/splitter/air thingy, whatever you want to call it.


Z axis motor mount. I didn't want to remake the entire Z axis motor/bearing block assembly, so the mounting plate for the larger motor also serves as an adaptor. The holes inside the circle will attach the plate to the current nema 23 mount, then the larger outside holes will attach the motor.


Here is a drawing of the new motor mounted on the head. With the air cylinder, spindle motor, and nema 34 Z axis motor, everything is a bit of a tight fit.
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
I made a little more progress after being out of town for a week. I made the mount for the servo motor and I am getting going with programming it. The drive needs to be tuned and it all needs to be wired in to the controller so the computer can run everything.

I can confirm that the talon grips I made work. I used them to make the motor mounting plate and the part didn't budge while cutting. You might notice that the outside of the plate is a little bit rough... When the tool was profiling it, I forgot to set "stock to leave" to .015" so the finishing tool would have some material left to remove. Oh well, it doesn't look terrible and it works, so I will use it as is.


Finished product fresh outta the vise.


And in her first public appearance, the new Lenze servo spindle motor all mounted up and dwarfing the the Nema 23 Z axis motor.


I have been instructed by the landlords (Aka Mom and Dad) to hold off on breaking into the breaker box to steal a 220v line to run the motor at full speed, so for the moment, I am stuck using 120v power. It works fine, but the speed is cut in half (Max speed of 7000 down to 3300) and torque suffers a little. At the very least, it is still going to be more powerful than the stock spindle motor, and the max spindle speed is bumped up from 5500 RPM to about 7250. Once I get the thing programmed and tuned, I will make some test cuts and see how it does.
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
I am still working on the Servo drive. It has an old version of the firmware that does not have autotuning. To get the new version of the firmware, you need a new version of the firmware already installed. I might be stuck trying to tune it manually I am thinking. I have sent 3 different emails to Lenze an all 3 were ignored (first sent 3 weeks ago) so I might be SOL in that department. I also tried calling them, and their system puts me on hold for about 10 minutes, then sends me to voicemail. No response there either.

Getting a little tired of working on the motor, I decided that I need to make something that isn't machine related on the mill. Its been too long since I made something that wasn't an upgrade or a part for the machine. With all this talk of "Ghost guns" in the news recently, I was inspired to make an AR-15 lower. It would give me a chance to use all the upgraded parts I have added to the machine and hopefully let it run on its own for a while.

The first side needed 9 tools to complete. They were

1. 3 flute .375" carbide end mill
2. 90 degree spot drill
3. 3 flute .250" carbide end mill
4. 3 flute .125" carbide end mill
5. 2 flute .625" insert end mill
6. .250" twist drill
7. .201" twist drill
8. .156" twist drill
9. 4 flute .375" ball nose end mill

This is the first time I used the mist coolant with actual coolant in the tank (in this case WD-40). It worked well for the most part. The only problem I had was that the flow of coolant would stop occasionally and I needed to open the needle valve on the side of the head to get it flowing hard, then turn it back down to where it was. I am not sure why it is stopping like that, but I will figure it out eventually. It was also very smokey. The garage filled up with smoke from the WD-40 burning off pretty fast. The door needed to be opened and fans run to keep it down to a more manageable level.

I used the mitee bite jaws on the vise and they did their job. I had to switch one of the jaws to the outside of the moving jaw. I couldn't tighten it too hard or the aluminum jaw would start to bend back. That didn't seem to be a problem since tightening lightly held it in place very securely.

For the first side, the mill ran for about 2 hours. There were only 2 problems that needed to be corrected. First, the .625" insert end mill started rubbing once it got down past 1" deep. I had to take it out, machine away the shoulder that was there on the lathe, then put it back in. It was nice to be able to pause the program, pop the tool out, fix it, and pop it back in and resume without any fuss. The second problem was that I roughed to profile first, then roughed the features in with the .375" 3 flute end mill. With less than .1" left on the bottom of the part and being held in the vise, and the tool extended out of the holder to reach the 1.5" depth around the part, there was a lot of chatter. I probably needed to back off the DOC and increase WOC instead.

Here are all the tools used.


Here is how it started. I just faced it flat before starting.


Here is the profile after the profile was roughed.


Here is the modification that was needed on the insert end mill.
Before:


After:


Righter after it finished roughing the features in the top. It is a good thing I paused it here to take a picture because while it was paused, we had some power flickers (a lot of storms in NC recently) and though we didn't lose power completely, the control computer rebooted. If I hadn't paused it, it would have crashed in the middle of the finishing pass, dropped the head, destroyed the part, and probably damaged the vise.


Here it is all done with the first side. Next it needs to be flipped and the second half will be machined.


Here is a close up of the first 3D rounded contour I have ever done. This was with the 3/8" ball end mill and I think it turned out very well.
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
Nice work!

Here is the coolant I'm using. https://www.amazon.com/gp/product/B00R9M0110/ref=oh_aui_search_detailpage?ie=UTF8&psc=1

1 gallon should last you quite a while once you get the mister dialed in. The difference between WD40 and coolant is impressive, and I would imagine much better for you lungs! Though coolant is not good to breathe either, so I wear my respirator when running mist.

PZ
I was hoping to avoid the respirator by getting it to run without fog... Does the coolant smoke at all when you are cutting? I need it mostly to keep the chips from sticking to the tool, actually cooling isn't as much of a concern. Does it lubricate the cutter as well as WD-40?

Also, do you dilute it at all before using it? Any discoloration on the part after using it? I can't remember which one it was, but one of the coolants turned aluminum parts brown.

I want to get some real coolant though. The WD40 is just what I have used with a spray bottle for the longest time and I had a gallon jug of it.
 

macardoso

H-M Supporter - Silver Member
H-M Supporter - Silver Member ($10)
Joined
Mar 26, 2018
Messages
297
NICE WORK!

Which indexable endmill do you use? How does it perform in aluminum? I'd like to use one, but I haven't found something that works well in aluminum and I can't justify the cost of a Tormach shearhog.
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
NICE WORK!

Which indexable endmill do you use? How does it perform in aluminum? I'd like to use one, but I haven't found something that works well in aluminum and I can't justify the cost of a Tormach shearhog.
I have a set of Zenit end mills that use AP?T (I think G but not sure). There is a .75" 3 flute, a .625" 2 flute, a .5" single flute, and a .375" single flute. I snagged the set of 4 of them, plus around 20 inserts for $50 shipped on ebay. They work well for what I do, but I am not sure how they would compare to a shear hog. I want one of those too, but also can't justify spending $240 on a single tool. With the new motor, they are ripping through aluminum pretty hard. The biggest cut I took after getting it set up tonight was 4.35 in^3/min, so at the very least they do as well as the shear hog if you can spin them.

NYCCNC recommends .2" wide, .2" deep, 40 IPM for using the shear hog with the Tormach 440. That is 1.6 in^3/min. The 440 also weighs at least double what the PM25 weighs, so I have trouble imagining the PM25 would be able to do much more than the 440 with the shear hog.
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
The spindle servo is up and running!! I can't believe how crazy this motor is compared to the stock motor. Right now I am running it with 120v instead of 240v, so it is not achieving its full 2 HP rating and its speed is cut in half. With the motor running at 3000 RPM, the spindle is moving at 6600 RPM. I did a few test cuts with my insert end mills and it was moving!

My standard roughing cut with the original motor was .3" wide, .05" deep, 35 IPM. That gave me .525"/min MRR and the spindle motor would get bogged down a little bit at the start of the cut. When I did the same cut with the AC servo, it didn't even notice it was cutting something. I had a motor RPM readout on screen, and I think at the very beginning of the cut, it fell 2 RPM for just a second. I started bumping it up until I got to the max feed which I had set at 96 IPM. At .75" wide, .05" deep, and 96 IPM, the motor dropped about 200 RPM and stayed there. It didn't sound like it was struggling but it was definitely working hard at that rate. That was 3.6"/min MRR. I had to reconfigure the controller to let me move the axes a little bit faster to see where the motor started to complain. I got it up to 116 IPM (4.35"/min!!) before I backed off because the lights in the garage were starting to dim. I am honestly not sure how that happened because the motor and drive were on their own dedicated 15 amp circuit, independent from the one the lights were on. But I didn't want to risk it and destroy something just when we were getting going.

I did a few test cuts that were deeper, but none of them sounded as good as .05" deep or could get close to the MRR before the motor started to struggle. I did manage to stall it once, cutting .15" deep, .35" wide, at 70 IPM. It only stopped for a second, but once I stopped feeding, it started right back up again. I thought I would need to reset it if it faulted, but there was no recorded fault and it kept going when I slowed the feed down.

I am running the spindle with an analog signal from LinuxCNC and it uses a relay to enable and disable the drive. The breakout board has an onboard relay, but I couldn't reach the headers to wire it in, so I connected it to an 8 relay board I have in the box.

I used the same pulley I had on the stock motor, I just needed to open up the bore a little bit to fit the larger shaft. If I stick with the same pulley arrangement, the spindle will go 13,200 RPM once I hook the drive up to 240v mains. I think it would shake itself apart at that speed though, so I will need to slow it down a bit and make a new spindle pulley.

Here is the new motor next to the old motor next to the new Z axis stepper next to a 2.25 HP treadmill DC brush motor. The new AC motor isn't much bigger than the stock motor, only slightly heavier, and at least twice the power. German Horsepowers are a lot stronger than Chinese Horsepowers.


The huge chips from the .15" deep cut. These were very loud running into the enclosure door.


I recorded a few of the cuts. I really like the .05" deep one at 96 IPM. The motor doesn't care, there is no chatter, the chips are cleared well, and I love the sound... I regenerated the tool path I used for roughing the AR15 lower, and the old one took 1 hour and 2 minutes. The new one, using the new speeds and feeds finished in 15 minutes, 32 seconds. Almost exactly 1/4 the amount of time!

I am going to mess with more feeds and speeds soon. I think these inserts just like a shallow depth of cut. There is a lot of space to explore between .05" and .1" deep though.

Huge shout out to @phazertwo for providing the motor at such a great price and @macardoso for helping me configure and tune the drive! This wouldn't have happened without them!
 

phazertwo

Active Member
Registered
Joined
Dec 31, 2016
Messages
202
I was hoping to avoid the respirator by getting it to run without fog... Does the coolant smoke at all when you are cutting? I need it mostly to keep the chips from sticking to the tool, actually cooling isn't as much of a concern. Does it lubricate the cutter as well as WD-40?

Also, do you dilute it at all before using it? Any discoloration on the part after using it? I can't remember which one it was, but one of the coolants turned aluminum parts brown.

I want to get some real coolant though. The WD40 is just what I have used with a spray bottle for the longest time and I had a gallon jug of it.
I diluted it 10:1, and it seems to be working great. It does lubricate well, and it didn't change the color of my parts. Hopefully I can get the mister dialed to the point that I don't feel like I need to wear a mask, but for now it's not constant enough.

Nice work on the motor, I'm very excited by this! I'm glad you're putting it to good use! Those cuts are looking really good, if you gear it down a touch like you were talking about you should find a bit more torque which will help. Of course getting it setup on 240v would be killer. You've really got me thinking about what to do with the other one!

As always, great work!

PZ
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
I diluted it 10:1, and it seems to be working great. It does lubricate well, and it didn't change the color of my parts. Hopefully I can get the mister dialed to the point that I don't feel like I need to wear a mask, but for now it's not constant enough.

Nice work on the motor, I'm very excited by this! I'm glad you're putting it to good use! Those cuts are looking really good, if you gear it down a touch like you were talking about you should find a bit more torque which will help. Of course getting it setup on 240v would be killer. You've really got me thinking about what to do with the other one!

As always, great work!

PZ
I will check it out, thank you for the tip! Their price does not seem at all unreasonable. When I was dialing in my mister, the pressure had to be crazy low to stop the fogging. I think I have it set to 8 PSI on the air line and about 10 PSI on the coolant tank. Even with the air line set to 15 PSI, it would fog like crazy.

I would love to see what the motor can do on a 940. I think I am going to run into rigidity problems long before I find the limit for the motor. I don't have a way to balance the spindle and tool holders at the moment, so I think I will limit the speed to about 8000 RPM. Right now it is geared 1:2.2. Their torque curve for the motor and drive at 120v stops at 2500 RPM (I was running at 3000), but if that graph is accurate, the motor was able to produce 3.39 Nm, which translates to 1.54 Nm at the spindle. Once hooked up to the 240v line, I will be going to 1:1.3 gearing, which at the same 6600 RPM at the spindle will give me about 2.25 Nm at the spindle. If I drop the motor down to 4000 with the spindle at 5200, it should give me 3.5 Nm at the spindle. The torque curve claims that at 2000 RPM, the motor can put out about 8.75 Nm, which should be plenty of torque at lower speeds. The motor also claims to have a top speed of 7000 with a slight reduction in torque, so that would give me 9100 RPM for using smaller cutters if I can balance the spindle a little better.

My Dad will be home this weekend and he is going to help me run the 240v line to the drive. I am going to make a separate electrical enclosure for the spindle drive to try to avoid noise and avoid building a new enclosure big enough to fit all of the electronics. Let me know if you need any of the info I used to get it running. Again, I can't thank you enough! This is a massive upgrade and I couldn't walk away from the machine since I was having such a blast turning scrap aluminum into chips.
 
Reactions: Z2V

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
I didn't realize I hadn't posted anything for so long... Whoops!

Since my last post I have:
1. Connected the servo drive to a dedicated 220v line (I keep saying 240, but I think its actually 220).
2. Run an AC line to the shop, no more 100 degree 80% humidity afternoons. Also I am not having any trouble with drives overheating.
3. Straightened the ballscrews, cleaned up the ballnut faces, and shimmed the nuts to increase preload.
4. Cut down the Y axis nut mount a little to slightly increase travel. I got about .375".
5. Started machining parts for a lathe attachment using the stock motor and quill bearings.
6. Machined a stepper coupler to connect to the Nema 34 shaft and mounted the Nema 34 Z axis motor.
7. Machined the second side of the AR15 lower.
8. Made a threadmill tool and threadmilled for the first time on the mill.
9. Made all 10 tool fingers for the automatic tool changer.

Connecting the servo motor to the 220v line did several things for me. First, it increased the output of the spindle motor to 2 HP from 1(ish) HP and the speed from 3000 to 6000 (Max speed actually 7000). Second, it took the spindle load off of the 120v lines in the garage. I was using 2 15 amp 120v lines to run everything in the shop. This meant that I could not run 2 of the larger power consumers at once (Milling machine, lathe, bandsaw, or air compressor) since any 2 at once would cause both of them to strain, or if the mill tried a heavier cut while anything else was on, it would trip the breaker. If I split the mill between the 2 120v lines (Spindle power on 1, control power on the other), when the air compressor kicked on, it would cause enough of a power flicker to cause the control computer to reboot. No bueno when it is cutting. Now, I have a free 120v line that can run the other machines while the mill is cutting on its own. So I can leave the compressor on to recharge, I can prep stock on the bandsaw, or work on the lathe while the machine is doing its thing.

AC in the garage is possibly the greatest thing I have ever done. In the past, I would soak through multiple shirts with sweat in one day and the machine would occasionally overheat the stepper drives. Now, its still warm, but much more tolerable. I have not yet insulated the door, but I can keep it around 80 to 85 degrees with the inside thermostat set to 75.

The X axis ballscrew was starting to concern me. The tail end would wiggle at least .250, if not more, when the table was farther to the right. It was also way too far out to support that end without binding issues. To straighten them, I took a pair of V blocks and a dial indicator and put them on my X2 table. I measured the point of max runout on the screw, then used the mill head to push on the highest point until it didn't spring all the way back. That took a fair amount of force. With the V blocks placed about 12 inches apart, the highest point was about .025" out and roughly 3/4 of the way down the screw on the drive end. Once I got that down to .005 or so, I just kept moving it back and forth until I found what point was the most out of round and pushing and working the screw into somewhat straight. Initially, I found 1 major bend, and 2 more minor bends (about .01" each). After straightening, I was able to get everything in to about .003" at the worst points. I didn't measure the machined end, but I wish I had. Once reinstalled, the far end of the screw wiggles maybe .01" and there is no longer an audible oscillation while the table moves.

I re-cut the faces of the nuts using soft jaws on the lathe. Most of the faces were rough machined and not ground, and looked pretty bad. The front of the flanged nuts on both were pretty bad too. I had to go off the assumption that the ball races would run true with the ground body of the nut. This may not actually be the case, but I didn't know how to measure off the ball races, and its not like I could make them much worse.

Here is the set up for the nuts facing. The nuts were definitely hardened, but cut well with carbide. In theory, the soft jaws ensure perfect (or at least very very good) concentricity.


Here you can see how far out the face of the nuts were. I had to take off about .015" to get it squared up.


Oh yea thats much better.


I always forget just how many fasteners the machine has and how many little components there are.


The extra shims preloading the nuts let me get the backlash on X and Y from about .0035" to .0015". I would like to get that even better, but I am happy with .0015.
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
I started working on a lathe attachment/4th axis for the machine as well. I am using the stock 1 HP BLDC motor and the large bearings from the quill for it. I have an idea for getting it to index automatically, but I don't think it will have full 4th axis capabilities. But 3+1 would be possible.

The 2500 rpm motor is going to be pulleyed down to 1000 RPM which should provide plenty of torque. I don't ever run my lathe faster than 1000, so I figured that would be plenty.

As with most of my projects, I started with some scrap plates. All of them had to be cut to size on the bandsaw before going on the mill. Who would have thought a little $150 bandsaw would be used so much and make my life so much easier?




I had to open up the bearing pocket for the front plate by about .002" for a heavy sliding fit (is that a thing?) I am very happy with that surface finish.


The rest of the parts were cut using a super glue fixture. Machining them was pretty uneventful and the machine ran on its own for a while with no issues. It probably ran for at least 6 hours that day.




Here is a look at almost all the parts and stock that will be used. I have not decided if I want to put a tapered bore on the spindle. I am trying to find a 2 piece jaw 4" 3 jaw chuck, but I have been unsuccessful so far.


I used a fixture to machine the second half of the AR15 lower. This was also uneventful (which is good) and it cut very well. Everything lined up nicely and it didn't move at all in the fixture.


I think there is a little bit of nod in the head somehow. It is trammed well left to right, but it might be off a little front to back. I am still happy with these finishes though.


This was one of the more interesting set ups I have done. I clamped my 3" toolmakers vise in the 4" vise, then used a clamp to hold the lower upright against the 3" vise. Here it is threadmilling the rear thread.


Its not the prettiest thread, but it works. I will need to buy a decent threadmill. They are a bit expensive though and I don't often need to threadmill.


I am thinking I will add another line for dedicated air coolant. With the mist, there is not enough pressure to clear chips from deeper pockets and it starts to recut chips if I don't blast them out with the air gun. I will just need some more locline and another solenoid valve.

I bought some stock to make a sheet metal brake to bend some sheet metal. I am going to try to make new way covers for both the Y and Z axis, as well as a cover for the head to keep chips out of the pulley and upper bearing. I have not decided how exactly I will do these covers, but I will figure it out as I go.
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
I got the 4th axis close to ready today. I machined the spindle shaft, finished the back side of all the 4th axis plates, drilled and tapped some holes, and did a quick test assembly. It is short 2 pulleys and 2 lock nuts before it can run. Then I need to find a 4"chuck with 2 piece jaws and/or come up with a vise to use with it.

Here is the shaft after everything but the front end machining.


Here is the backside of the rear plate being machined. It is cutting the face that will mount the motor.


Test assembly.


There's the repurposed spindle motor.
 

macardoso

H-M Supporter - Silver Member
H-M Supporter - Silver Member ($10)
Joined
Mar 26, 2018
Messages
297
Nice finish on the 4th axis spindle! What steel?
 

macardoso

H-M Supporter - Silver Member
H-M Supporter - Silver Member ($10)
Joined
Mar 26, 2018
Messages
297
Very nice! Just a thought, but you could either machine the pilot diameter for a front mounting bolt-thru chuck, or you could put a 5C taper in it.
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
I always thought that given enough time, these machines will pay for themselves. I had my houses backflow preventer inspected recently and it failed the inspection because one of the check valves was leaking. They said the ears used to install and remove them had broken off so it was damaged beyond repair. A new one runs anywhere for $250-$350. So I said to myself "I have all these machines, there has to be a way to repair this item that is damaged beyond repair."

First thing to do was remove the damaged check seat. It actually wasn't too hard. I just used the lathe to turn down a rod to the ID of the check seat, then superglued the rod to the rubber seat, and twisted it out.



I got a new check seat (actually an entire service kit with 2 check seats and o-rings and such) for $21. Turns out putting the new one in is kind of hard. But wait, they sell a tool for it! For $160... I said not today, parted off the part of the rod with the superglued seat on it, stuck it in the mill and cut 4 little grooves in it, then boom 5 minute later, the new seat was installed.



In my eyes, the 2 machines just earned at least $230 (a penny saved is a penny earned right?) with about 20 minutes of work. A shop rate of $690/hour isn't bad right?
 

shooter123456

H-M Supporter - Gold Member
H-M Supporter - Gold Member ($25)
Joined
Jan 20, 2016
Messages
396
In an attempt to finance some new machine parts, I thought to myself "Self, lets try to make a few kits for sale! Maybe there is a market out there!" So I have had the machine choochin hard for a few weeks now trying to get a few parts that looked great and make sure I have the programs all tuned in right. It is basically the same design as the one I have had on the machine for 7ish months now, except I added some chamfers and radii to try to make it look a little nicer.

I wonder if my idea regarding the kits is any good though. I would welcome feedback here. My thought is "I make the custom parts that need to be machined, then the user sources the hardware like ballscrews and bearings that are available through 100 different vendors." Theoretically, if you were looking to convert a machine and could save $200-$300 over the other offerings by sourcing your own hardware, would that be an attractive option, or would you prefer to pay a bit more and get everything all at once from one person?

Here's a few pictures of the parts so far. They all need a bit more work done and I need to make some flanges. I love how the chamfers from the 3/8" spot drill look. So much easier and cleaner than deburring by hand. The pics are a little dark because I turned a few lights off. Otherwise you can't see much on the part besides the reflected glare.





 
[6]
[5] [7]
Top