well here is my Mill! It will probably take decads to build ;) but I will post pictures as I go. Sorry for the photo quality but my phone is the only camera I own. Gues I will have to go buy one just for this!

enjoy!

hear is a concept of the finished product.

last upload didn't take. here it is again

damn the file attachement aint working.. anyone want to tell me how to attach jpeg files?

Should work ok unless it is a big file?

Don't forget to click "upload" after browsing for the file.

Is that mill a scratch build or did you start with something?

Eric

I started with a very used Ruttland round column bench top mill. Motomitch's square column conversion inspired me to do the same. The one thing I'm doing alot different is using a Air cyclinder as a counter balance insted of a large weight.

I tried to upload the jpeg file (converted from solidworks) the same way I did the initial photos and it dosen't seem to work.

I am giving it another go so if there is a picture then.....

here is some more progress on the very expensive not enough time in the day hobby project! :D The first is a close up of the spindle assembly and the second shows the spindle assemble with a spindle motor mount.. which i should have bolted up by tomorow But I still haven't got the pullys (do to lack of brainpower in ordering). ;)

wow those realy shrunk quite abit I will post them again with a little biger picture!

here are the bigger pictures TIR was Much less than .0005 (Didn't have a .0001 gauge handy :) )

Is that the spindle assembly from the Ruttland mill??

the actual spindle is from the ruttland. I have just removed all of the casting and the lame quill down feed and re-used the spindle and the housing for the spindle. I have replaced the bearings with high quality Nipponees bearings. and use Kluber highspeed grease (the best on the plant @115.00 tube, I got it free :D ).

With this bearing grease combo i got very smooth action and have no perceptible deflection and in the tenths runout. (didn't have a .0001 gauge handy but will recheck soon).

The onlything I have to still do to the spindle assem. is make a front grease seal as the original is either non existant or missing. I plan to run flood coolant so this is a must!

here are some preliminary picts of the Z-axis column with the IKO linear bearings on. It was a little bit of a pain to true up but after assemble the rails are very smooth with no perceptible deflection with my 185lbs of weight on it.

Can wait to try it but there are still so many part to machine so I will keep pluging away in my non existing free time. :D

Oh and a pic of the x-axis table extensions. What a ***** that was to do, Had to line up the dovetails on machine table so that the matched to the chinees junk. I got it done and trued everything together but I would hate to have to disassemble everything and reline it up again. (nuts) that would be nuts. But you know how murphy can be (the gremlin man not you ;) ) So I will probably get some practice lining it up in the future. (machining those pin bosses dosn't sound all that bad of an idea now ) :D

I recently had someone email me these questions (which I will also post in their thread).


Hi Michael

Great job on your round column mill conversion. Thanks for putting the pictures up. They help allot. If you have anymore I would love to see them. Do you have a web site?

I am starting on my round column mill in the near future and I am just trying to get some ideas of the best way to go about it. I have been looking at that round column of this mill for along time trying to figure out what to do with it. The limit of 5 inches of Quill for Z travel is just un-exceptable, especially when trying to change tooling. I knew what I wanted to do with it but everyone told me that I was nuts to try it. Now that I see other guys doing it, (like you) I don't feel as bad to give it a try.
I have some questions which I hope you don't mined me asking about your conversion.

(1) What size is the vertical tube that you used for the replacement column?
(2) I see you welded some bars onto the front edge for mounting the linear
rails. Did you have any problems with these warping anything after welding?
(3) What did you have to do to true everything up after welding? I am limited
to what I can machine and the column would be to large. I guess I could take it
to a machine shop to get it trued up if needed.
(4) What size are your linear rails? They look massive. Wow, six bolts per
bearing.
(5) What are you planning to use for a spindle motor?
(6) Do you have a good place to get replacement bearings for these spindles?
(7) What are your thoughts on trying to keep the coolant out of the lower
spindle bearing of these cheaper spindles? I don't think my spindle even has a
proper seal in it down there. I think it has a rubber washer that screws into
the bottom of the spindle body? And I am planning to put the mill in a fully
enclosed cabinet and use full flow coolant. So there is going to be lots of
coolant flying all over the place. What about making some kind of aluminum
adapter that would fit onto the bottom of the spindle that you could put air
pressure to for a positive pressure to keep the coolant out. Something like
what the big boys do on their spindles? A type of air purge? Any thoughts on
this?

I have lots of other questions, but I will wait for another day. I have ask to many questions now. I really appreciate all your help with my questions. Thanks.

Talk to you later.

Bill Blackburn

Also known as Willyb


1. The tube I used was just laying around and measured 6x3" with 1/2" wall thickness I dont have the length on me but the travel on the slides will be just over 21"

2. the base plate and the top plate are machined before welding. then while welding you make damn sure to sqare everything up and tack it together and check it again. (I think the stress got to me here because I must have check the thing about 20-30 times before finale weld ;) ) After welding I let the thing sit in the sun outside for a couple of weeks for some heat cycles (a heat treatment would do the same thing, better but, I was being cheap) Then I put two kurt style vises in my VF-2 and machined the Rail pads being sure to true the column BEFORE MACHINING to the Base. This column was so thick I doubt seriously if the warpage was all that serious to begine with.

3&4. I have a machineshop so in effect I cheated with professional machines. but I only had a vf-2 at the time and had to compromise on the length of the support pads. if you look at the picture you can see the rails hang off a little (the vf-2 only has 30" of travel) and the rails are IKO linears LRX25 (basically 1" wide rail) I actually was looking for the next size down but those were almost 2 times the price do to availablity.

5. the spindle motor is a 2.5hp continuous duty treadmill motor wich is massive. I have pictures but they will have to wait till this weekend to get posted as I cant find the charger and dont have time to look for it (just moved)

6. Any bearing house should be able to help you. The ones I listed previously in this thread are some of the best on the market. The Nipponees rate their bearings lower than abec specs so you can get them to perform at the next higher Abec standard than rated. (i am tired hope that makes sense).

7. Hadn't realy though of an air purge that actually might be a good Idea. I was going to make an oil seal similar to an oil seal on the crankshaft of a car but probably a double seal insted of single. Will give some serious thoughts on the air thingy though! glad you mentioned it.

Miljnor

I have been looking over the pictures of your spindle head. Are the main plates made out of steel?
How thick?
What is the width of the box?

I am going to a steel plant tomorrow and hope to pick up some stuff to start building the new column. Will get the tube, linear rail mounting material and plates for mounting the column to the base. I will let you know how I make out.

Willyb

The main plates are 8x10x1" thick and the welded are 4x10.5x1" and the side plate is roughly .5" thick to cover the rest.

The whole thing is steel except for the shiny white looking stuff ;) thats Aluminum.

only a few more parts and the mechanical will be ready for compleate assembly!

I have the z-axis almost complete. ballscrew in place with top thrust bearing pack, idler bearing and balscrew. would show the ballnuts but its very tight in there! will take some pictures of the ball nut assemble on the next teardown.

Hi Michael

Thanks for the pictures.

(1) What are you using to hold the bottom of your Z axis ball screw, is this somekind of adjustable mount to put some tension on the ball screw?

(2) What is the idea of the little side plate covering the side of the bottom right hand linear bearing? There dosen't sem to be one on the left side?

(3) Do you know what the length of your Z axis linear rails are?

(4) What size did is your Z axis ball screw?

Thanks again for all your help.

Willyb

Hi Michael

Thanks for the pictures.

(1) What are you using to hold the bottom of your Z axis ball screw, is this somekind of adjustable mount to put some tension on the ball screw?

(2) What is the idea of the little side plate covering the side of the bottom right hand linear bearing? There dosen't sem to be one on the left side?

(3) Do you know what the length of your Z axis linear rails are?

(4) What size did is your Z axis ball screw?

Thanks again for all your help.

Willyb

The bottom of the ball screw shouldn't have any tension. That is mearly an idler bearing to keep the end from flopping around.

The small plate on the spindle sub plate is for the counter balance to anchore to. I am using a pressurized cylinder for this.

I don't have them here but I believe the z-axise rails are 30" long giving me slightly under 22" of travel.

The ballscew is a 5/8" - 5tpi Roton ballscrew with dual preloaded ball nuts. I also bought the longer ball nuts for the added load rating. Although I don't know that I will need it as everyone else seams to buy the other shorter ball nut. I guess only time will tell but if there is a money shortage then the short ball nut is probably the way to go, as teh long one is roughly 3+ x's the cost.

thanks for the interest. Just wish I had the dang thing working!

Its been a long journey and I know It will never be done but I would realy like to have it running so I can start cutting some chips and making peices for the next upgrade! :D

Well here is the z axis column with most of the part on.

It was almost complete and then I found that I ordered the wrong length bolts for the column base! Its always something! ;)

I would have all the machanicals done this weekend but the dang bolts are going to hold me up. And I don't realy know if the cheesy bench I have everything on will hold it. It weighs in at just under 900lbs, and thats without tooling and vise!

Looks like I am going to have to make a metal bench with some sort of retractable wheels for mobility. But first I think I will get the electronics done and see how it moves around then do the table and big disassemble and reasmbly with everything loctited in and then away we go!

here are some more pictures. Enjoy!

Wow, that is beautiful work!

awww shucks! twernt nothing! ;)

Realy though I wouldn't go that far! if you want beutifull look at the sweeds web sight! 5bears something. just google it. I am a professional machinst, I don't know what Sweed does for a living but his machine puts mine to shame!

Thanks for the positive comments though makes me want to finish it faster! :D

Hi Michael,
Your mill is looking good and heavy duty.what software are you going to use to run it?
I was using Qstep to run mine,and then I switch over to windows xp and couldn't get Qstep to work right anymore :bs: so I got mach 3,got it back up and running that mach 3 software is some good stuff. :D

mitch

That's the nicest conversion I've seen. Nice work. Keep us up to date on it please, can't wait to see it cut some parts.

nervis1 thanks for the kind words man. will definitely take lost more pictures. I still have to take the thing apart for final assembly (need to loctite everything ) So I will endever to take assembly pictures (but no promisses on how many ;) ).

I am going to use mach3 as I bought the license before the price went up :D. and have been using it on a little el cheapon 7x10 lathe. I have been using the lathe to familiarize myself with the software and its been working great.

amazing how bad my typing gets when i am watching my spastic kid by myself without the wifey to run interferanc! (flame2)

here are the latest.

except for unforseen things and waycovers it's done mechanicaly (although I already want to change the servo mounts so they don't stick outward).

Now for the electronics. Hopefully since i have all the parts (I think :rolleyes: ) it shouldn't take more than oh say another week to 10 years :tired:

here are some updated and new pictures and enjoy!

I had to change the servo mounts for the x and y! They just stuck out too far. Now they are all tucked away, although I had to modify the brackets twice now and it looks like the Y axis is going for a third rework. but here are the most recent upgrades.

Dont have the belts yet but they should be here by wed..

Well I had to change the X-axis motor mount once again! (chair)

Now I think I have it in its finale resting place. I had to move it to clear the way covers that I bought (you can see the one for the front of the Y-axis, although I haven't made any anchores for them yet.)

here are the pic's, Enjoy!

Very nice, Mike, looks like it will have no problems cutting just about anything. Very heavy duty, nice job! How many RPM will it end up cutting at?

covers are the worst part
I could have built another machine in the time I took to cover the mini mill

I just got the controls active now I am working on the limit switch locations.

Yes the Way covers are being troublesome I already have the Bellows covers that fit very well, but, they interfere with all of my limit switches! So more design changes are needed.

The spindle will operate at 7000rpm Max and the lower limit I have no Idea. depends on how the motor performs.

I have been able to test rapids to 170ipm and feeds to about 120ipm without load. Anything higher on the feeds and the software has problems with the hardware excel (i I think.) But as I don't think the spindle has the HP to push anything other than the lightest cuts at 120ipm I don't think there will be issues!

more pictures will be forthcoming but haven't had the motivation to post and will probably wait till way covers are present.

That mill is looking sweet, now that I,ve seen that you welded your base and column together I think I,ll do the same. What are you using to control the spindle motor speed?

Actually he welded the base to the column tube, then bolted the whole assembly to the base. I wouldn't recommend welding cast iron without the proper knowledge, heck, I wouldn't recommend it at all.


Jon

Oh I,m sorry forgot to mention my base and column are steel construction.

Great Job Miljnor!!!!
Your mounts are impressive. Did you cut those on a CNC??? Nice Job!
Would it be possible to post Pix's of your limit switch installation. I'm doing that to my lathemaster this next week and to be honest, I need some ideas. The way covers are going to be a pain I already see. But, beats chips in the ballnuts!
Soon to be making chips!
billyjack
Cheers!!!!
:cheers:

My project has been stalled for a couple months/weeks do to other projects (on the house and RC planes).

As far as limit switches go. I have locations picked out for them but haven't installed them yet as I need to finish the way covers first. And I recomend you finish the covers first as well as they represent the biggest hurdle in interference with the limit switches.

It has been a realy PIA to get the way coveres worked out on this beast. I think I have it but need to finish the outside trim of my house before I can get to it. So it might be another few days to a week.

If you think way covers are easy on a metal machine think again. I recomend if your doing a scratch build to really think hard about covers before you make anything do to the complexity and difficulty in making something work.

I new I was screwed because I was using a modified machine not a ground up build.

As stevie How long his took and you will see. They take as long as the whole machine does to do.

As far as the welded column. Its all steel and I agree with Jfettig on the cast welding. But if your going to weld either you can make it work here is a link to another like mine (my inspiration actually, as he did it first)

http://www.cnczone.com/forums/showthread.php?t=7564

you will probabaly have to ask for a repost of the pictures as they are generally not available because they are on his own webpage.

also as far as controling the motor I have a variable speed controler from surplus center that will control a 2 HP brush motor and you need single phase 220v to it and then I will use the cnc4pc speed controler hooked to it. Eventually I will make a speed controler (we already got a thread started for it, but until I read more I was in over my head and hadden't finish testing it)

i have almost all the way covers in place and should be at least up and running without limit switches soon.

I can see the light at the end of the tunnel. Although the little niggly stuff always takes the longest. So that light could very well be another train! ;)

here are some pictures.

Nice Mike. I remember when it was just a pile of parts in your shop. Your allmost done! So what RPM will you end up with at the spindle? I got one of those same motors.

its a 2:1 ratio so I can get 7000 rpm but the one my employee has actually spins at 4k so it might be 8k rpm. time will tell Hopefully by the end of next week I will have a test cut.

Great work Mike.

"I thought I saw the light at the end of the tunnel, but it was just my boss with a torch bringing more work" :)

thanks for the positive feedback.

"I thought I saw the light at the end of the tunnel, but it was just my boss with a torch bringing more work"

wouldn't want you guys getting bored! :D

and it does pay the bills right! :cheers:

Hey where did you get your way covers from? Any more progress?

I got a little more progress but no photo's as I have too many projects going right now!

The weather has been nice for flying so I have been getting as much stick time in as possible (RC airplanes). And unfortunately it takes away from my machinery building time.

Not only that but to run power to my spindle I will need to wire 220v single phase and that means allot of rearranging the garage to get the conduit in. And if I am rearranging then I will put the cabinets up that have been sitting on my floor forever!

So needless to say I am being lazy (in a way). Will try to get power by this weekend (no promises).

The way covers I bought from MSC. The ones for the upright is a square bellows that I cut into two pieces and used half for the bottom and half for the top.

very nice mike
seems like you thaught a everything didnt you
my compliments and respect for this one to me it looks as nice as the 5bears machine anyway

well i wouldn't be meself if i wouldn't spoil the fun but i m goin to ask anyway since your free not to answer here goes :how much did you pay for your spindle bearings

i dear ask cause i just haven't been able too find any pricelist anywhere i been true rockwell's bocabearings and lots a dutch sites and too get a quote you've gotta know first what it is you need exactly wich i haven't got a clue of only thing i can find is the wholesalers here in amsterdam and they rip ppl off.if it would spoil your fun posting this i understand m8

thx for sharing and good luck

Always happy to help.

Unfortunately I don't have any thing special as my bearings. Other than replacing the original mills bearings with high quality replacement bearings, I just transplanted the whole spindle from the original mill to this one.

My reasons for using the old set up were:
1. See how long taper bearings last at the usage levels I am going to be using it at.
2. wanted to see if accuracy was good enough for home use.
3. It was convenient and very cheep, as I got the bearings from one of my partners (who owns a bearing house) for nothing.
4. This is in no way an industrial application and I feel anyone trying to duplicate a commercial spindle for something that amounts to a hobby machine is spending money in the wrong place.

I know for a fact you can get similar accuracy out of tapered bearings to a cheeper commercial mill. But the qualifier is how much load are you putting on them and what is your duty cycle and the most important (Ask NC cams) how anal are you about assembling them and getting the right fitment?

Commercial units are made a certain way for lots of reasons, low maintence, longevity and accuracy. I don't realy car much for the first two (although it would be a bonus) and the third I will be happy with .0005" tolerence as my closes fit on my parts so spindle run out is not as critical except maybe to tool life (although I did get very little tool run out, I think in the tenths but its been a few months)

Cost is always a bad question to ask me as I spend money on weird things, waste it on other things and get even more things free.

Hi Michael

I've just seen your way cover solution and am very impressed. I have a Tormach PCNC1100 on which the way covers are a bit iffy to say the least, so I am looking to make an improvement. I would very much appreciate if you could share some general information on how you solved the problem.

Best Regards
Phil

..........

It has been a realy PIA to get the way coveres worked out on this beast. I think I have it but need to finish the outside trim of my house before I can get to it. So it might be another few days to a week.

If you think way covers are easy on a metal machine think again. I recomend if your doing a scratch build to really think hard about covers before you make anything do to the complexity and difficulty in making something work.

I new I was screwed because I was using a modified machine not a ground up build.

As stevie How long his took and you will see. They take as long as the whole machine does to do.

you can buy bellows from msc.com

i used this one for the z axis: and cut it in half to make 2 covers. One for the top and one for the bottom.

http://www1.mscdirect.com/CGI/NNSRIT?PMAKA=63415947&PMCTLG=00

and I used these ones for the y axis covers:

http://www1.mscdirect.com/CGI/NNSRIT?PMAKA=63416200&PMCTLG=00

and
http://www1.mscdirect.com/CGI/NNSRIT?PMAKA=63416218&PMCTLG=00

but you better be sitting down when you look as they aren't cheap!

But spending a huge amount of wasted time on ones that don't work will make you think they are cheap! Don't ask! :D

Well after draggin my feet for almost 5 months I have begun the final leg of this project!

Took my first test cut on some wood this morning and will try to post some more pictures later tonight.

I kinda micky rigged my speed controler just to get a test cut in and improve my motivation position (to get her done). works good but I don't think it puts out enough juice, but time will tell.

I was wondering what is the status of this conversion. I see the last post was on august 2006 and i just found this as i am doing research to convert my round column to square and i am also looking to use the motor from my treadmill to power my spindle but i have some concerns. will the treadmill motor be strong enough to cut through steel without problems also what meterial did you use for your column it looks like a piece of rectangular tube if so what size and is there any deflection when machining any help would be appreciated

Well I've been using this mill on and of for a little while now, never have installed limit switches but havn't really notice any problems...just got lazy after it started working as it runs great without.....But Now I'm moving and wont have a place to store it So am selling it and the enclosure as is....So if anyone is interested just PM me or put your info in this thread