[miljnor]

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!

[miljnor]

hear is a concept of the finished product.

[miljnor]

last upload didn't take. here it is again

[miljnor]

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

[kong]

Should work ok unless it is a big file?

[balsaman]

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

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

Eric

[miljnor]

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.....

[miljnor]

here is some more progress on the very expensive not enough time in the day hobby project! 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).

[miljnor]

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

[miljnor]

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

[ViperTX]

Is that the spindle assembly from the Ruttland mill??

[miljnor]

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 ).

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!

[miljnor]

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.

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 )

[miljnor]

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.

[Willyb]

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

[miljnor]

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.

[miljnor]

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.

[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

[miljnor]

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!

[miljnor]

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!