[Bird_E]

I have begun the conversion of a Lathemaster RF45 Clone. I have some pictures on a new web site that I just started.
Check it out if your interested. I should be adding alot more content in the comming days /weeks.
http://www.rlberg.com

Thanks!
Bob

[acondit]

Bob,

What servos are you using on this conversion?

Alan

[pete from TN]

I have the same lathemaster mill and I am getting ready to do my own conversion. If you do not mind where did you get the servos and how much were they, what are the specs? Which ballscrews did you get and where, any and all details would be great. Like the ultra beefy mounting you are doing. Only thing I might have done different is the z mount, a friend has the same machine as well and he did his out of aluminum for the z and had to redo it in steel to get it to stay where he wanted it and also to not flex I think he said. Nice work and the machining looks very well done. Are you surfacing these parts on the other cnc and with an endmill or facemill? What are you gonna do to keep swarf and coolant off the motors and belt drives? Inquiring minds wanna know.... Peace man...

Pete Matos
865-363-9218


P.S. if you can gimme a call, I love to chat with other guys with similar interests let alone similar machines.. Peace

[pete from TN]

Can't wait for another installment....peace....

[BrendaEM]

In the RF4.5, how did you surface the end of the base to accept the plate? Did you use the SX3, with its head turned 90 Degrees?

[Bird_E]

The internal Zmount is still using the the original cast iron. I used an 1" alum. adaptor to mount the ball nut. The Z and Y Axis are all made from 1" 6061 alum plate with back to back angular contact bearings.
The base was machined on a large monarch VMC tha guys at work did for me. This is going to allow me to mount the Y axis to the back of the base instead of the from. I should get 10 -11" of travel in Y when all done.

I'm about to start the X axis soon. I need to still come up with a plan for protecting everything from swarf.

I just scored a Bijur automatic oiler from ebay so I need to work out the lubrication system as well.

The ball screws are 3/4" 5 TPI Ground. I also found them on ebay.

More to come
Bob

[pete from TN]

So you are gonna go thru the back of the machine with the y axis mount. I thought from the pics that was the front but it is hard to tell. I like the idea of going out the back to keep junk off the motor and drive. What kind and size servos are you using and where did you get them? Again, really like the beefy mounts you are doing. I am going to be starting my conversion after I finish this current job I am working on that needs the mill for some serious hole boring using a boring head as well as some profiling. Are you gonna attatch the encoders to the screws or the motor shafts? I am really interested in your buildup because I am going to be using ideas from this one and a few from another mill already under power. Lots of neat ideas and differing ways of accomplishing the same thing. So you are saying you machined the z axis ballnut mount and finished the bore to accept your bushing a-la Industrial hobbies website. I like the look of your mounts for the ballnuts, the preloaded nuts are beefy and look very professional in your machined mounts. Nice workmanship there. The nut carrier is aluminum and the bush is steel? Thanks for the information man...peace...

Pete Matos
865-363-9218
[email protected]


p.s. where are ya located?

[Bird_E]

I have just posted some more pictures and information on my site. It should answer some more of your questions.
Erie, Colorado.

[Bird_E]

In the RF4.5, how did you surface the end of the base to accept the plate? Did you use the SX3, with its head turned 90 Degrees?

I started to do it with the X3, but it was taking too long. So I brough the base into work and had it done on a big Monarch VMC.

[jalessi]

Bob,

I was wondering if you are leaving the ballscrews floating on one end or will they be supported?

Your CNC Controller "rack mount chassis" is really thought out well, superb layout! The cleanest I have ever seen.

Awesome Work!

Jeff Alessi
[email protected]

[Bird_E]

I'm going to leave the screws floating at one end. Based upon my X3 conversion which also has them floating, It has never caused an issue. The screws will never really spin that fast to be a concern.
Bob

[jalessi]

Bob,

Are all three axis floating?

With the ballscrew floating will the machine hold a .001 tolerance?

I like the idea of the floating ballscrew, without the additional bearing support and only a 1/2 length screw the difference in cost and time for the all three axis should save several hundred dollars.

I am always short on cash for toys so a couple of hundred dollars is alot to me.

Thanks for taking the time to explain your work.

Sincerely,

Jeff Alessi

[Bird_E]

My X3 will hold .001 with floating screws and they are rolled. I don't think it would be a problem with the rf45. If I was concerned about it I would have supported them at both ends. The only thing it's going to prevent is screw whip, but my screws will never run at an RPM that will cause it to happen.
Bob

[jalessi]

Bob,

Is the x axis ballscrew full length?

Jeff...

[pete from TN]

height of the center of the ballnut mount on these installations. Obviously careful measuring but is there a trick to it? With your setup going out the back you can determine the height yourself but when you go out the front as most do you have to recreate the original height exactly or the screw may bind or am I missing something? I like the idea of going out the back like you did and I guess I can have my buddy machine my casting on his larger bridgeport mill. I see you put the x axis carrier on it to keep it flat. Could you not just lay it on the top of the casting where the area between the y dovetails will rest on the mill table? It appears to be a machined surface.... Man I wish you had bought your components from a particular supplier so I could just get the same stuff but oh well. I am not too knowledgeable on this stuff so I would like to follow some known working designs wherever possible. It seems that if you are making controllers for your work then you are fairly experienced with this. Of all this stuff it is the electronics I fear the most. The controller looks like a large pot of multicolored spaghetti to me. Oh well if I can get a design down I can solder pretty well it is just the wiring diagram that I will probably need to get mine done. Thanks for all your assistance and I look forward to seeing your machine under power very soon!!! Ya are gonna post a video of it running righthttp://www.cnczone.com/forums/images/icons/icon7.gif
Smile anyways, nice work and good looking stuff...peace man..

Pete Matos
[email protected]
865-363-9218

[Bird_E]

I did some rough, well as good as I can get, measurements for the ball nut height and drilled a 1" rough hole in the back of the casting. It's not that critical, heres why, build the ball nut mount, attach it, then attach the screw. Now the screw sticks through the hole in the back of the casting, now install the bearing plate on the screw and use some camps to hold it nice and flat against the casting. Don't clamp it too tight, also don't tighten the ball nut mount too tight. Now run the table back and fourth, everything should settle into place. Once it's smooth as silk, tighten down the ballnut mount bolts, and tighten the clamp up on the bearing plate. Run the table back and fourth a few more times to make sure everything is smooth. Then, use a transfer punch to transfer the mounting holes in the bearing plate to casting. take it apart, drill and tap then put it all back together....Sweet!

Don't worry about the electronics.... I think thats the easiest part.
I have built 5 controllers on the past using Geckos servo and steppers... it's really pretty easy.
There are some really nice servos for sale at www.homeshopcnc.com. I would have used these if I didn't have what I have already.

I have two extra servo motors the same ones I'm using for the Z axis, I would be willing to sell one if you are interested, I want to keep an extra for a spare. They are pretty big!

I may need to put a break on the Z axis so it doesn't fall when the power is cut to the Z axis. I'm not planning on using any counter weights at this point.

He also has ball screws.

Bob

[pete from TN]

I have never built anything like this and I am not sure about a great many things. That controller you built is sick looking, nice work. I like the idea of setting the y like you said and running it back and forth until it feels right. I guess you would just measure the screw at the front of the travel and then at the back and make sure it is square with the ways and then lightly tighten it up. Then just transfer the marks once you are feeling good about it. I am assuming you feel like there is enough meat in the back of the mill casting to mill it flat as you did. I was thinking that If I were to do it that way I might not remove the lower part of the skirt and just make a mount that has a step in it to keep some extra rigidity on the perimeter of the casting. It is pretty thick back there is it? you would know better since you have it all apart. Just how thick is it post machining in that area now? I like the servo motor drive out back very much. I guess from what you are saying you will have the screw unsupported in front and I guess just put a plug in the factory hole. Could you possibly make the screw come out the front and put a long sliding fitment on the screw for a front support bearing and put a handwheel to have some modicum of manual (I know I know you will not want it once the cnc is working)? I really love my mill and I am anxious to get things going. shoot me an e-mail and we can talk about the servo motor. I may use it for the z....peace man and thanks again for your informative posts.....

[pete from TN]

Did you put a bush in the factory z slide like the Industrial hobbies website depicts to stave off slop? I now understand the way you used the factory cast iron z bracket and made an adapter to accept the z ballnut, nice looking setup BTW. But I am talking about where the cast iron part interfaced with the z slide...peace man...

[Bird_E]

Pete,
Yes, I made a new bushing for the Z axis out of steel as noted on the IH site. As far as the back of the Y axis casting, the very lower part of the skirt the lower 1/2" is thin, about .150. But it steps up to about 1/2 thick most of the way. It more then beefy enough!

You could easily punch a hole in the front of casting and fit it with a support bearing of some sort and a hand wheele. That would be really easy to do in this setup. But you won't need it, but very good idea!


I add some more pictures to my site with more detail on the Y axis, it should give you a good feel as to where the front of the screw is in relation to the original hole. and the back end of the casting.
I finished up the motor mount tonight for the Y. Need to get as design for X

I have most of the parts I made designed in solid works, if you need any dimensions or anything let me know.

As far as the controller in the pictures, that has alot of crap packed into it.

including the PC, Hard Drive, PC power supply, Network switch, G100 , stepper drives etc.......

The one I'm building for this machine won't be nearly complicated. I will keep the PC external to start with.

Bob

[pete from TN]

It looks like the y is now about an inch or so lower than it was before. The z looks very nice. I guess with the computer packed into the controller as well it does look pretty cramped. How difficult do you think it is to do that tho as it seems you might be able to use the power supply from the computer for some things. Plus the cases are pretty cheap and come in varying sizes and shapes. I think I gotta get some parts on order soon so I can start this thing. I am just needing the mill to complete some custom scope sidewheels I am making which is gonna help me pay for all this stuff. Pretty soon tho.... Keep up the good work and I would get the solidworks info from you but I do not have solidworks so I prolly could not view it anyway. Thanks man and I am sure i will have more questions as you go so if you don't mind I really appreciate it....peace and have a good night..