Bolton ZX45 Conversion

[gd.marsh]

Exactly the point!

Just wish I'd have reached that conclusion before buying the first set ..

I'm no engineer or even a machinist for that matter. Just a guy who enjoys tinkering around in the garage to see what I can accomplish. If this is the worst mistake I make on this project .. I've got it made!

[Shev]

I think you are wasting your money on abec 7 bearings...abec 5's are prolly pushing it in a chinese mill. The spindle and housing aren't machined accurate enough...

[gd.marsh]

After cleaning & repacking with Kluber .. I reassembled the splined shaft & spindle. Then proceeded to do a run in sequence starting at 500rpm in forward for 20min then in reverse for 20min. Bumped the speed up to 2000 & repeated .. continued to bump up in steps of 1500 & repeat until I got to 8K. About 4 hrs. of run in time all together.

Hottest temp measured during the entire process was 110 Deg. right at the bottom of the spindle, shortly after hitting 8K .. After a few minutes it began to drop down again finally settled at about 104-105. I could not get a reading over 100 anywhere else I measured.

Everything seems smooth .. Even passed the 'Nickle test' right on the head at all speeds except in the 5200 range .. (Stand a nickle on edge with out tipping over while machine is running)

I am getting some rattle from where the splined shaft fits over the spindle. It's a rather loose fit so I'm not sure what I'll be able to do about it.

Measured the runout inside the bevel on the spindle and could barely detect any needle movement with my .ooo5 Chinese indicator. I'll break out the .0001 Mitutoyo tomorrow & see how it reads.

Guess it still comes down to how well things hold up under load .. I'll just have to see when I get there. Still a long way to go on this project.

Gary

[AiR_GuNNeR]

Thanks for the update Gary. I'm sure I speak for everybody that I'd love or this thread to keep going with updates!

[BobWarfield]

Very promising break-in. Now you'll have to make some chips!

Cheers,

BW

[gd.marsh]

Fixed the rattle between the splined collar & spindle .. Everything running quiet, smooth, & cool ..

Double checked run-out inside spindle taper = .0001 as measured with a Mitutoyo indicator ..

Please don't follow my lead, I don't really know what I'm doing = your results may vary!

Gary

[gd.marsh]

I know it's a terrible quality video .. my phone is the only means of video I have at the present time ..

My intention is to give a perspective on what 8K sounds like on one of these mills .. it's moving!

[gd.marsh]

Here you go BW ..

Got my hands on a video camera so it's a little better quality than the last.

8000 RPM
3/8" 2 Flute End Mill
Approx: .050 - .060 DOC
Approx: 20 - 25 FPM

One added bonus .. after making the video I fired it up again and let it run at 8K for another hour .. highest temp is now down to about 103 ..

Perhaps making some cuts helped seat the bearings a little better?

Anyways .. so far = So Good!

[cornbinder23]

I haven't even watched the video yet, I am still stuck on the 20-25 FPM!!!
man thats smokin FAST

[BobWarfield]

I haven't even watched the video yet, I am still stuck on the 20-25 FPM!!!
man thats smokin FAST

Heh, it should be able to go even faster. In the video it was just loafing along making tiny little chips and very little sound. According to G-Wizard, you should be able to go a full diameter (0.375) deep at 20 IPM and still have a little safety margin with a carbide endmill.

In other words, that machine is gonna sing.

Cheers,

BW

[gd.marsh]

Guess I meant 20-25 IPM .. not FEET!

Duh!

Gary

[mattbesquare]

where do you measure the temp at? - sorry, dumb question. just watched the video. You may also get some added thermo sink if your gearbox is still sealed and you fill it. My entire machine gets really hot when I run it (stock powertrain), I havent measured it though. I was thinking if I ever decided to uprate it I would mount an oil cooler and a couple of case fans to the back...maybe I should measure mine to make sure it isnt overheating.

May I ask how much torque you are using for your washers? I have read all kinds of answer to this one, but wanted to see what someone who actually built an rf45 changer is using.

[gd.marsh]

mattbesquare,

By how much torque I'm using for the washers .. I'm guessing you mean the Belleville washers? Haven't used any yet! .. don't have the power drawbar set up.

I believe Hoss has mentioned in one of his posts that he only ran about 750# on the X2 Freak which was sufficient for load on that machine ..

I don't really know what it's going to take on the 45 .. Tormach claims they have 2500# on theirs .. but they use a 4" triple stack air cylinder to compress it.

I'm planning to add the power drawbar after I get the machine up & running in CNC mode. Will experiment at that time with how much my 4" single stack cylinder is capable of compressing.

Gary

[mattbesquare]

mattbesquare,

By how much torque I'm using for the washers .. I'm guessing you mean the Belleville washers? Haven't used any yet! .. don't have the power drawbar set up.

I believe Hoss has mentioned in one of his posts that he only ran about 750# on the X2 Freak which was sufficient for load on that machine ..

I don't really know what it's going to take on the 45 .. Tormach claims they have 2500# on theirs .. but they use a 4" triple stack air cylinder to compress it.

I'm planning to add the power drawbar after I get the machine up & running in CNC mode. Will experiment at that time with how much my 4" single stack cylinder is capable of compressing.

Gary

Well, with your RPM I would definately consider more lbs of torque.

As far as force capacity for your 4 inch cylinder that depends, with a direct connect you are looking at about 12.5*psi so 100 psi is about 1250 lbs of force. this is from their manual, but they do not go too much into units so assume I am wrong. I need to refresh my physics anyway...Ill get out my book tomorrow.

Of course you can increase your force with a lever. I am going to mount a 2" bore/2" stroke cylinder to the right of my gearbox a la Hoss (are you tired of hearing this yet Mr Hoss?), and with a 2" stroke should have no problems leveraging to 1-5 hundredth.

Give me a lever long enough (and a 2" bore/stroke Bimba at 100 psi) and I will move the world...just not very much

I was planning on starting at 1200 lbs and moving up (I read it somewhere, so I assume it too is wrong)... I have a lexan sheet for a shield and never go to the back part of the shop without glasses-just a habit. Still, I am not pulling 8k rpm.

[gd.marsh]

Thanks Matt,

Good information there ..

Since I have little understanding of physics .. I planned on setting up a test rig & finding out what this cylinder will do. If the single stack doesn't have enough punch to handle it .. I guess I'll either be shopping again or re-designing my system. I'd like to keep the cylinder plunger directly over the drawbar so I can squeeze the Bellevilles with push/pull force rather than put all that downward force on the spindle bearings.

My experience in the woodworking industry (35+yrs) has left me with the distinct impression that a faster spinning cutter increases centrifugal forces for sure, but actually decreases the lateral force needed to move the cutter through the material.

As has been mentioned in earlier posts .. I won't be spinning any large tools at 8K .. When I do use that speed it will be for engraving, or with smaller end mills on aluminum or plastic ..

I seem to recall the Tormach video I watched. It says they found 2500# to be necessary to hold a 1/2" end mill while cutting through 1" of aluminum in 1 pass! Pretty impressive, but I just can't see myself even trying such a stunt as that ..

Gary

[gd.marsh]

Just couldn't bring myself to pay $276 for Tormach's 1-1/2" 4 flute face mill with an extra set of inserts.

Went this route instead ..

Shars 2" - 5 flute with 3/4" straight shank holder & Tormach conversion kit.
$170 including 5 extra inserts.

[sfrankland]

Just couldn't bring myself to pay $276 for Tormach's 1-1/2" 4 flute face mill with an extra set of inserts.

Went this route instead ..

Shars 2" - 5 flute with 3/4" straight shank holder & Tormach conversion kit.
$170 including 5 extra inserts.

Have you tried it out yet. Been looking at the samething.

[gd.marsh]

Actually I have not used it yet .. been too busy with other things for the time. Soon as I get a chance to check it out, I'll post a quick review. The APKT inserts sure do look nice. I'm quite impressed with the whole set-up.

[gd.marsh]

OK .. I stuck the face mill in the manual mill for some initial testing ..

First cut = .030 doc /1200 rpm /25 ipm .. Nice!
Second cut = .025 doc /3000 rpm /35 ipm .. Nicer!

I'm fairly confident this thing will do a beautiful job on the CNC machine at higher rate of feed.

G-Wizard says it should cut .025 @ 1843 rpm & 64 ipm ..

[sfrankland]

Very impressive. I have been eying this Glacern FM45 2.5" Face Mill, but the setup you have would work a little better with my MT3 spindle.