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phazertwo

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#1
If your only interested in pics/tech/the good stuff… skip this next paragraph, trust me, I’d do the same thing. Also you will find a thread index at the end of this post, it should be useful for navigating to what you want to see and skipping all the BS :eagerness:

I’m FINALLY getting around to making a upgrade thread on my PM-940-CNC-VS, but first a little background. I have been interesting in fabricating ever since I realized a drill bit could cut metal, not just wood. Just out of high school I got a job as an apprentice machinist working for a crazy SOB, but I got plenty of hands on experience learning the ins and outs of, as some would call it, a “clapped out old Bridgeport milling machine” and some junky Chinese lathe. Later I was working for a different company where we had access to a small prototype machine shop, with a much nicer Bridgeport and a much nicer Cincinnati lathe. My interest in manual machining peaked during this time, after I made a few parts for my Toyota Pickup, which was modified for rock crawling. While working this job I was introduced to CNC machining via a vendor I became friends with… Fast forward years, and years, and actually over a decade later and 3 more jobs where I was always on the edge of learning CNC and I finally decided to take the plunge and buy a 3 axis bench top unit.

I had been thinking hard about buying a CNC, and of course dreamed of owning my own Tormach 1100, but not only am I not rich, I tend to be pretty cheap. So when I stumbled across the PM-940-CNC-VS (from here on out will call it the PM-940) I suddenly felt like I could actually own my own machine… That was in Januaryish of 2017 and the mill was in my garage setup and running by February…

Loaded on the trailer.

Wanted to put it in the truck as it would have been a smoother ride, but no way to get it out of something that high at home.

Didn't take any pics of unloading it. I had 3 buddies waiting for me when I got home and we made it happen in about 30min. It's current home:


Inside the cabinet:



I got a clamp set and a vise with the mill (forgot to take pics), turns out that the vice I ordered was out of stock, so they upgraded me for free BOO YA!

I do have to say, Precision Mathews has been an absolutely awesome vendor to work with. Questions answered extremely fast, all my pesky little OCD questions answered (like 20 emails worth)! I HIGHLY SUGGEST them. Keep in mind that I have had this mill for over a year before I even considered starting this thread and I still say that. The mill was completely functional out of the box, all upgrades that I’ve made or are making are because I’m serious tinkerer and I have a passion for precision/accuracy.

Anway, this thread will follow my adventures of upgrading this machine to hopefully be a bad-mamba-jamba that can keep up with a Tormach 1100, but for less money and with me learning a great deal more about CNC!

Here are two similar (like SUPER similar) threads that I follow, and that have inspired me:

cut2cut:
https://www.hobby-machinist.com/threads/my-pm-940-cnc-modifications.57976/

pburgh:
https://www.hobby-machinist.com/thr...ontroller-conversion-to-centroid-acorn.65196/

More to come!
PZ

Thread Index:

 
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phazertwo

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#2
Right out of the box I was impressed with the quality of the machine. Everything was smooth, and short of some flaking paint was in good order. I promptly loaded Mach 3 on a computer and started setting up the machine. At the time I was eyeballs deep in a engine swap for my Toyota and desperately needed some custom fuel line clamps, so I designed them based on a piece of UHMW I had laying around and started programming. This was the first real part that I ran, and I ran 5 at a time, with profiling since I didn’t have the correct size ball end mill. I was ecstatic. I worked under the truck the whole time the machine was running and just listened for it to stop, at which point I would change tools and set it back in motion.




One of the finished parts:


At this point I was all smiles!

PZ
 

phazertwo

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#3
The honey moon didn't last long though. I had some issues that probably could have been resolved, like getting the limits to work right (which could have actually been loose wiring), the machine being very "jerky" and last but most importantly, I couldn't get the e-stop to be an e-stop. I would hit the e-stop and good two seconds would co buy before the machine would actually start to decelerate. After messing up a corner of my pretty vice and trashing two test parts and some mills when the machine didn't stop on time, I had had it. The nMotion and M3 were just not cutting it. So I started doing research on better controllers, you can read about some of the options and the decision I ended up making here, on page 2-3 of cut2cut's thread:
https://www.hobby-machinist.com/threads/my-pm-940-cnc-modifications.57976/

The Centroid Acorn was at introductory pricing at the very end of 2017, so I ponied up and made it happen!

While I was waiting on it to ship... This happened:


Never again would a lack of e-stop destroy a part, tool, or vice.

PZ
 

phazertwo

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#4
ACORN!

When I went to install the acorn, I realized that the back plane in the cabinet was setup for 3 or 4 drives, which makes sense because PM offers a 4th axis. So first things first was to move all the drives over to make some extra room.
Before moving the drives:


After moving the drives and with the Acorn in it's final resting place:


I used a simple piece of 1x2x11ga rectangular tubing and the original mount for the nMotion to mount the Acorn. It’s not the prettiest thing I have ever made, but it works quite nice.

The Acorn does not rob 5v from the computer, so a 5v power supply is needed. I used this cheapo mean well from amazon, seems to do the trick just fine. It mounted quite nicely behind the Acorn. I should have enough from for a 4th axis drive if I ever get one.



One thing I did that was against the recommendation of Centroid, but has caused no issues so far, is a shielded bulkhead connector for the ethernet cable. I would have liked to send it out the bottom, to keep crap from falling in it, but I didn’t have enough cable to pull it off, so its sticking out the top.


The specs for the computer to run the Centroid software is well above M3, so a new computer was in order. I was able to order components to upgrade mine for about $350. Hind sight being 20/20, I converted my dads router to Acorn as well and was able to buy a computer for $100 that worked perfect. Anyway, I shoved the computer back in the same cabinet near the mill.


Here is a list of the parts I used:

Meanwell 5v power supply

Shielded ethernet bulkhead connector

Shielded ethernet cable

PZ
 

phazertwo

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#5
Wiring the Acorn is a pretty simple thing. I think I re-used all the wiring from the nMotion, however you do need to add the 5v power supply. Acorn provides great schematics specifically tailored to different drives, so I just picked the Leadshine schematic and went for it. I didn’t make any changes to the VFD wiring or settings, just simply tied it into the analog output terminal of the Acorn and it worked flawlessly.


With the nMotion I could never really get my limits to work, and they needed to be switched form NO to NC. So I tore into that next, and it turns out that there were a few broken wires, and most of the terminals were loose. So I went through the entire machine and found that a fair number of the wires were loose. I would suggest to anyone who has a 940 CNC to check all your terminal connections to make sure they’re gooten-tight. After that the limits started behaving correctly.

This is how the limits need to be wires for Acorn:


Last thing had to do was change the settings in the Acorn to work with the normally open (NO) e-stop. An NO e-stop is quite dangerous, so I ordered up a new e-stop from the goold ol’ amazon and swapped it out two days later. All the wiring in the PM was quite nice, the loose connections could easily be from transport from China. The ONLY thing that I really didn’t like was the NO e-stop. I’ve been witness to a pretty bad industrial accident, and several smaller ones… don’t mess with e-stops and safeties. They are normally closed (NC) for a good reason.


After all the wiring was complete the Acorn fired right to life and connected to CNC12 no problem. I was up and running!

Parts used:
New E-stop

PZ
 

phazertwo

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#6
And I apologize, I didn't realize there was a time limit on editing posts... so the thread index in post one is dead. Unless there is a super nice/awesome/cool Mod out there that can either bestow upon me the access to keep editing, or just toss some links in there to keep up!

PZ
 

phazertwo

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#7
The Acorn was very easy to setup and tune. It still took me a night of dinking with it, but after setting up and tuning M3 it was no big deal. I wouldn't say it easier or harder, just different.

After all the tuning was done it was time to make some chips. I found myself at a loss of what to build, so I just made a gizmo in Fusion and had at it. I had some blocks of UHMW laying around, which I hate machining, but I figured what the hell, good for a test. I used all brand new HSS tools, so it worked out okay, but not perfect.



I ran most of it with a 4 flute 0.5" end mill at 3200 RPM and about 0.004 IPT with a 0.35" step over. It was a little nerve racking to watch this setup that I had done nothing but basic tests on run at 51IPM just chewing thru material.... Worked perfect, no hick-ups.

So I made a mating part, they fit super tight...






With just this one run under my belt, my confidenice was already higher than it ever was with the nMotion and M3!

PZ
 

phazertwo

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#8
After the plastic went so well, I setup to make and aluminum test part. I was worried about speeds and feeds for this, so I kept it simple. Just grabbed a scarp block of aluminum, faced it and put a slot in it.



Worked out perfect, and I was pretty happy with the surface finish of the walls of the slot. Next I flipped the block over and made something more complicated. Something that had some different features I could measure, and push my S&F's a little bit further.



Everything seemed to come out with in 0.002" or so, I'm thinking I measured the end mill wrong. It was the first time I programmed the fly cutter and it did great.... Except I didn't deck the scrap far enough, you can still see a little bit of the slot that was running through the center of it. This was also the first time I used the chamfer tool to deburr the part, if you haven't tried this I strongly suggest it, I do it on every part now. All and all for a test part I was very pleased.

PZ
 

phazertwo

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#9
From the factory PM states that the 940 is capable of 100 ipm in the x and y, and 75 ipm in the z. However I was never able to get the z to 75ipm. Sure it would run 75 ipm, but it would miss steps regularly.... and it ALWAYS misses them moving in the positive direction, which means your tool always ends up lower than it should be. NO GOOD. So one day, I was cranking the manual z crank and was thinking "damn this is tough, no wonder the motor misses steps" then I realized that the motor is turning this 90° gear and it really doesn't need too... So I tore into it, and I removed all the guts for the z manual (sorry I didn't take any pics of this). Then I built an actual real FUNCTIONAL part to block off the opening.

I had an awkward shaped piece of 0.5" black anodized aluminum that had a spot in the middle of it just perfect for the cover plate. I drilled the three holes with the closes drill bit I could find to the actual OD of the bolts, and punched the pattern in the plate, including the counter sinks. Then I was able to cut the rough shape on the band saw and bolt it to a fixture plate. Quick program to clean out the outside and it was done.



Surface finish was pretty good, though no picture ever really shows it right. Defiantly getting better at this!


After I pulled it off the fixture plate I used the pistol drill to drill the holes out to the proper clearance size and everything fit perfect. Installed in it's new home:


All and all I highly suggest this mod. It made the whole z move smoother, and MUCH quieter. Not to mention I can run 75 ipm now, without worrying about it. The only down side is that you CANNOT move the z unless you power up the machine. I make sure I always leave it in a good spot when I power down, and a few times I have had to power it up just to move the z up or down while working on the mill. Not really a big deal to me.

PZ
 
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phazertwo

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#10
So, as it turns out, as a hobby machinist I'm on a budget. I consistently scour Amazon for tooling, and have some favorite tools I found there... here they are:
You might notice that all of these tools are 4 flute, which I like because I can move faster with the same IPT, however they tend to gum up with aluminum and I have to hit them with WD-40 a lot, or just take very fine cuts. I decided to start looking into mist coolant.

This is the the story of that.

First off, I ordered a solenoid from Amazon. The Acorn’s output wasn’t rated for enough go juice to run it so a new relay needed to be installed. I had some very small relays left over from some industrial gear I de-commissioned, so I removed the fwd and rev relays that were much larger than they needed to be and replaced the with these tiny guys.
Before:


And with the new, smaller relays:


Next I got a simple mist coolant nozzle from Amazon… it’s cheap. We’ll see. I removed the factory bracket for flood coolant and built a nifty replacement out of the same 0.5” black anodized aluminum as the z cover plate. Again, it turned out awesome, and mounted right up.

The bracket:


Mounted in place:


And with the nozzle base attached:


After the nozzle was mounted, it was time to mount electronics and pneumatics. I decided that I want a regulator on this setup, so I used an old filter/regulator setup and just mounted it to the side of the machine. I also bolted the solenoid and a manifold to the machine. The manifold gives me some ports to grow into for some other cool things…



I had some water bottle sized/shaped tanks that were used to collect waste ink, and they even come with a mount! I pulled them out of the scrap pile when the company went under and have been holding onto them for 10 yrs… glad I didn’t pitch them. A simple 0.5” spacer and some 1/8NPT holes to allow air in/out and it was good to go.



The idea here is that I can control air pressure from the regulator, and coolant with the ball valve that lets air back into the coolant tank… I was worried that it would siphon coolant when the head is lower than the tank (it did), and that the ball valve would not be able to control the flow of make up air coming into the tank (it couldn't). I figured I needed to start somewhere, so I let if fly just to see what happens.

Ran the lines along with the z home switch wires, the ¼” pex tubing helped stiffen up the whole bundle which helps keep it from getting snagged on stuff… just an added bonous.


Then it was time for a test part...

Parts used:
Solenoid
Nozzle and base
Coolant

PZ
 
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phazertwo

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#11
I had two big steel parts that a friend had given me over a year ago to fix, and I was feeling bad about still having them and having done nothing to fix 'em! So I decided that this would be a good test for the coolant, because I would need to build an aluminum fixture that would need a fair bit of material removed.

I programmed it a little more aggressively than any cut I had run so far. I used my favorite roughing end mill, and I knew for a fact that the flutes would gum up far before this with out constant WD-40 spritzing... Game on!

Tool path:


And the details:


That's 0.003 ipt, at 38.4 ipm, with all the RPMs the 940 can muster. 0.1125 step over (30% of cutter Ø) and I'm leaving 0.020" to clean up with a 6mm carbide, but I'm bringing it right down to the deck. Fixtures don't need to be pretty.

Finished fixture:


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!

However... the setup needs work to be perfect. When the head is down it siphons pretty bad, and the ball valve on the tank cannot meter the coolant at all. I was putting out way too much coolant with the thing barely cracked. On the next few parts I manually opened and closed the valve to conserve coolant.

Fixture worked perfect. Look close at the closest hole, it's an oval, that's one of the things I needed to correct. One of the parts that needs fixed:




Here is the other plate... the water jet that cut the part crapped out before finishing:


After machining:




Again I pushed the mill pretty hard one this one. 0.002 ipt 0.075" WOC, 0.500" DOC. Everything seems to work really well... until the tool started pulling out. Backed it off to 0.250" DOC and it cut just fine, next time I will likely bump the WOC.

That pretty much brings us up to date, which means things will slow down a little bit, and I will include far more of my research planning, and questions.

My next step will be spindle upgrades...

PZ
 

phazertwo

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#12
After months of going back and forth and back and forth... I finally decided on AC bearings for the spindle. I was looking at P5 tapered roller bearings, but wasn't real excited about the limiting RPM and that P5 is about the highest grade you can ever get...

I ended up going with some NSK AC bearings:
7206CTRSUMP3 - NSK Precision Angular Contact - 30x62x16mm
7207CTRSUMP3 - NSK Precision Angular Contact - 35x72x17mm

It was about $240 for the two. These should be very high precision bearings, and are rated to 18k RPMs greased. I don't intend to get anywhere near that kinda of speed, but it will at least allow me to hit my goal spindle speed range of 100 - 7500 RPM with two speeds.

I have not yet figured out exactly what I'm going to do for "gears" besides that I want to use J profile ribbed belt/pulleys. I would REALLY like to come up with a nifty way to change pulleys automatically, so if you've seen anything cool feel free to drop a line or a link here so I can take a look. To start I am just going to make a sliding motor plate and run just the high set of pulleys, as I will need to get the mill back up and running to make what ever parts I will need for an automatic gear changer... thingy...

PZ
 

WyoGreen

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#13
My wood lathe uses varible pitch pulleys (with a V belt) to vary the speed with the twist of a lever. My wifes hybrid uses the same setup for it's transmission, using a metal belt. The same setup is used in Snowmobiles, again with a heavy rubber V belt. So the setup can take considerable torque.

It might be something to check into, Steve
 

phazertwo

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#14
I'm actually well versed in the world of snowmobile clutches, and the idea of a change on the fly infinitely variable setup sounds awesome. Due to the nature of my controller, I would have to know the gear ratio that it's operating at, and have a way to change it to pre-set "gears" if that makes any sense. I know the CVT's used in cars these days are computer controlled, unlike a snowmobile/4wheeler that uses springs and weights to actuate the clutch as it spins up. If I could figure out how to control one like a car does... that It would be the ticket... Honestly though, it sounds like a whole bunch of parts and complexity.

Good idea though! Keep em coming!

PZ
 

phazertwo

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#15
The head of the mill is torn down, and cleaned. The oil that came out of the head looked/smelled/felt just like the stuff in the automatic oiler. It was full of grime and crap, after I got the top popped off I found that the gear case was full of gunck including metal shavings and other small particles. It could be sand from the casting process, but I doubt it because the rest of the casting is free of sand. Anyway, the top bearing on the spindle was in really rough shape for a bearing that has >20hrs on it (almost all of those hrs at max speed). Here are some pics.
Here you can see the rings of "stuff" on the edges of the oil:


Under the cap:


A look at the "stuff" left over in the bottom:




Another look at the "stuff" and the weird grease that was in the bearings, and here you can see that the rollers actually don't have much grease packed around them... turns out when I got them out the bearings didn't have any grease "packed" into them:



And the bottom bearing, again you can see not much grease "packed" in the rollers:


Upper race, you can see serious scaring near the middle of it... If I had to guess I would say the pre-load was too loose:


And the upper bearing itself, scared to match the race:


Lower race and bearing looked perfect, so I didn't take any pics. Also didn't take any pics of it clean, but you should be able to see it in the re-assembly pics.

All and all, the fit and finish on all of the machined parts in the head were quite nice. The spindle and quill fit together nicely and the press fit on the bearings and races were good. A little more cleaning before oil, some better bearing packing, a touch more pre-load on the bearings and it would be about perfect... I still think that bang for buck you couldn't beat this mill with a club, considering that all of the heavy metal (un-replaceable parts) seems to be good quality.

I've also started getting the head in Fusion... it's a bear of a job trying to get everything dimensioned properly, but it's coming along nice.

PZ
 

phazertwo

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#16
Brown Santa left me a nice little gift this afternoon.


I never would have guessed that I would think bearings are sexy... I was wrong. These are marked to show the max run out with an o, and the outer race has a V that tells you which way to install it, and where the max run out is. SUPER cool, though I'm not sure it's going to help me because I don't know where the max run out is on the spindle and quill. Also the -2 indicates the deviation in bore size in microns... that 0.002mm... or 0.000079" freaking cool!


Getting excited to put this thing back together.

PZ
 

navav2002

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#17
I am replacing the bearings in my PM932m mill. I'm interested in what grease you are intending to use on the roller bearings??
 

TomS

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#18
I am replacing the bearings in my PM932m mill. I'm interested in what grease you are intending to use on the roller bearings??
When I converted my PM-932 to AC bearings I used Kluber Isoflex NBU 15. Not cheap but highly rated. My mill has 8800 rpm capability and I've run at that speed for more than an hour on numerous occasions with no problems.
 

phazertwo

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#19
I am replacing the bearings in my PM932m mill. I'm interested in what grease you are intending to use on the roller bearings??
Like Tom did, I'm going to use Kluber Isoflex NBU 15. It certainly is expensive, however the precision AC bearings were a lot more so it's not worth it to cut corners IMO. I was able to by a small amount of it from The CNC Specialty Store so it wasn't too bad.

https://cnc-specialty-store.com/gre...m-tube?zenid=c288e5e92d51aa4139e3195aff46151a

PZ
 

phazertwo

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#20
Well I chickened out big time today. I was going to install my new bearings, but realized a few things that held me up. First was that the upper bearing will just be open to the world, anything can fall down in to it.


Even if I put the seals back in, the seals are a Ø35mm ID and the spindle is only a Ø28mm, not only that, there will still be an opening at the splines that will allow crud through.

Second, I was looking through all the gizmos I keep around the press for tooling, and I have nothing that will work well to pushing these things in. I'm sure I can get them in there, but I don't want to push on these beautiful bearings anything but the right way...

Unfortunately I need the mill to make the proper press tooling and a new seal adapter to plug the opening on the top... Kind of a catch 22. So I ordered a set of VXB ABEC-5 AC bearings to run in the mean time. They were about $90 for the set instead of $240, so I figure these can be a practice run, and buy me some time to get other parts made...

Today wasn't a total loss though! When I first started this, I ran the motor while it was chucked in the vice to figure out how many poles the motor has. It didn't sound so good, and was actually vibrating, so I ordered new bearings for it at the same time I ordered the spindle bearings. I DID have all the press tolling I needed to get that done (pretty easy). Now she sings, and is smooth all the way up to 150hz. And in case anyone was wondering, it's a 4 pole motor (1800RPM at 60Hz). before I put the motor back together, I took the time to tap the holes on the cap that hold the fan assembly to 10-32.


I had tightened these screws so many times trying to keep the thing from rattling that they were all stripped out. With the larger threads, and some blue Loctite I don't think I will have to listen to it rattle ever again... but only time will tell.

PZ
 

phazertwo

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#21
Well... I've been busying doing everything BUT working on the mill. We had a knarly wind storm two weeks ago and it put the finishing touches on my crappy fence. 2 days 9 posts, 30 stringers, 240 pickets, 1600lbs of concrete, one earth auger, and two DAMN good friends later, I have a fence again.
Building Fence.jpg
New Fence.jpg
It's much improved, not only because it's not falling over anymore, but it also has a gate. That means I can put MORE **** in the backyard!
:rolleyes:

I also had to do a fire drill re-gear of the front and rear differential of one of those buddies Land Cruiser...

While all that was going on some parts did come in. The new VXB bearings (I just noticed that for some reason the pictures of the NSK super precision bearings are gone..) and they are going to work perfect for a "test" run. The quality is surprising, however they are no match for the NSK bearings.
Left is the upper NSK, right is the upper VXB:
bearings.jpg

Also, the pulleys for the "test" belt drive showed up:
Pulleys.jpg

They are sitting on some 0.5" aluminum plate that I will use to build a "test" motor mount, and the rod to the side is to make a new quill lock. My plan is to get the mill up and running again with minimal machining, since I will have to borrow a friends manual machine to make parts while it's out of action. Once it's back in action, I will re make a lot of these parts, and add a power draw bar, and a two speed system. I will also make special press tooling to allow me to push the NSK bearings in with out messing them up.

Unfortunately progress will likely be slow for a while. We're coming up on our annual trip to Moab UT, and I have to get the truck ready to go. Hopefully I can get some time here and there to work on it, but most likely nothing significant until June...

PZ
 
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TomS

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#22
Do you ever slow down? I'm getting tired just reading through your post! LOL.

I had the same issue with the upper bearing on my PM-932. After thinking a while the light went on and I realized that the spindle drive pulley acts like a slinger and prevents most anything from getting past the splines during operation. This proved to be true because about six months after I did my conversion I opened up the gear head and the interior was as clean as when I assembled it.

I don't remember reading what your upper RPM goal is but seals have a RPM limitation. My upper limit is 8800 rpm. I didn't find any seals that would live at that speed.

Hope this is useful information.
 

phazertwo

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#23
I try to keep busy...

It is very useful information! I did consider that the pulley would be protection, but my spindle pulley is so small (67mm) that I figured it would still be a problem. What size is your spindle pulley?

Here is the seal I plan to use, should be good over 10k rpm:
https://www.mcmaster.com/#5154t122/=1cp1m10

My goal is 7500rpm on the top end, and I should be able to hit that at 120hz. Theoretical top speed should be 9000rpm at 150hz, but there is no torque up there.

PZ
 

TomS

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#24
I try to keep busy...

It is very useful information! I did consider that the pulley would be protection, but my spindle pulley is so small (67mm) that I figured it would still be a problem. What size is your spindle pulley?

Here is the seal I plan to use, should be good over 10k rpm:
https://www.mcmaster.com/#5154t122/=1cp1m10

My goal is 7500rpm on the top end, and I should be able to hit that at 120hz. Theoretical top speed should be 9000rpm at 150hz, but there is no torque up there.

PZ
My setup uses a two step pulley. The large pulley is 5"diameter.

16,300 rpm, Wow! When I was looking for a seal the highest rpm rating I could find was about 5,000 rpm. Thought about using a labyrinth style seal but the price was a bit much.

Lack of torque at the upper rpm range hasn't been a problem for me. Usually I'm running end mills 3/16" and smaller in aluminum so no need for much torque.

Good luck with your retrofit project. Your thread has been a good read.
 

COMachinist

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#25
Hi PZ
Could post the numbers and the place where you bought the NGK bearings I want put ne bearings in and up grade to 2hp 3ph moto for better control on my rpm. I like to run a faster on the aluminum parts I make.
Thanks
CH
 

phazertwo

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#26
I ordered them for qualitybearingonline.com. 7206CTRSUMP3-NSK, and 7207CTRSUMP3-NSK. They are out of the UK, so I had to pay in lbs, but paypal handled the conversion for cheap.

I decided to go with them even thought there is probably someone closer that deals in good ol' $$$, but they were quite helpful while trying to find precision tapper roller bearings.

PZ
 

phazertwo

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#27
Well I got back from Moab Saturday afternoon and was back working on the mill last night!

First I got the VXB bearings out of there packaging and cleaned up. They are nicer than I first thought, which is fantastic.
IMG_20180604_194619.jpg

Then it was time to load them up with the ISOFLEX. I'm pretty particular about the way that I pack bearings. I pack them from one side until the grease comes out the other side. Then I just smear it all over.

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The 50g tube is just the right amount for the two bearings.

Then came the hard part. How to press them in with out pushing on them wrong. I found some press adapters from another project that worked just right. It's like $15 bucks on the Amazon.

IMG_20180604_213245.jpg

The larger of the adapters worked great for the big bearing and the smaller for the smaller bearing.

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Then I ground down the old cone race so it slipped in and out of the quill.

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Coupled with my Harbor Freight 3/4" press adapter... I mean 3/4" drive socket set, it worked like a champ.

IMG_20180604_201616.jpg

Don't forget to put the set screw / collet key in before you put it all together... It's a pain in the ass to do afterwords, ask me how I know...

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For the smaller bearing I had to rely on the angular contact. I had to push on the inner race even though it was pressing against both races. Seemed to go just fine.

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After that I set it up so I could tighten the spindle nut. It also allowed me to spin the whole setup, and man is it just SMOOTH!

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None of the fingers on the spindle nut keeper were even close to lined up... of course. So I found this on the ol' Amazon, think it should keep the spindle nut tight.

https://www.amazon.com/gp/product/B00UHE3DHG/ref=oh_aui_detailpage_o00_s00?ie=UTF8&psc=1

Feels real good to have some progress after working on other stuff for the last few weeks. Next step is to try to get some mill time on my friends mill so I can make the motor plate. That's the last piece I need before I can get it choochin' again.

PZ
 

phazertwo

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#28
Well a month later and I finally have a very small update.

I ended up at my parents house for Independence Day, and was looking at my dads home brew CNC router and thought, why don't I make a temporary motor mount plate out of wood... Maybe it will work, maybe not, but hey it's what is holding me up at the moment and it' something to do.
IMG_20180704_192716.jpg

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My plan it to use this to make an identical motor plate out of 0.5" aluminum. I'm hoping it will last long enough to get it done... or maybe the motor will fall off... I guess we'll find out.

PZ
 

phazertwo

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#29
Got an incredibly small amount done yesterday. I mounted the motor to the wooden motor mount, and got it all attached to the mill. I will defiantly need to trim the casting, which I knew I was going to need to do. Unfourtunatly I ordered the largest pulley that I could fit in the head, which was 140mm... With the belt on it only gives me ~2mm/side of clearance. I am going to have to step that down to a 132mm pulley to feel comfortable running it...

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I'm very glad that I made the first motor mount out of wood. We'll call this one REV p1, the aluminum REV A will rotate the motor a bit to help get the electrical connections in a better spot, along with have some large holes to help get the belt on the back side of the pulley.

In case anyone was wondering why my progress has been slowed to a crawling pace... we are expecting our first kid at the end of October and I have been spending most of my time with house stuff getting ready for a half pint. That along with some crazy weather (wind/hail) that has caused damage to our house/vehicles I've been very tied up. HOPEFULLY I can get the mill back together and making parts before half pint shows up and my time in the shop takes a digger!

PZ
 

phazertwo

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#30
OH MAN!

Guess who showed up early!
IMG_20181022_203058.jpg

Born 10/21/18 at 1:10am. Mom and baby both did great, and everyone is now home trying to figure out how this all works!

In preparation for the little man showing up, I cut down a big cottonwood tree that was dying in my front yard. We had to rig most of it out so we didn't hit the house, it was a ton of fun.
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Those are just a few pictures of the 6hr time lapse we took... maybe some day I'll turn it into a vid.

Then I had to build a shed, which was much less fun, but it's done none the less. The shed is a big deal because it will allow more space in the garage, which hopefully will make it easier to work out there when I do actually get some time!!

IMG_20181014_093606.jpg

In the mean time, I've been working in Fusion trying to get the new belt drive system finalized... Hoping to have that done soon so I can order parts and get the mill running again. We'll see how it goes.

PZ
 
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