I was tossing the idea around of buying a desktop mill which I would convert to CNC. I've seen the plans at http://www.stirlingsteele.com/millplans.html and those looked pretty nice. Has anyone bought and used these plans? Any comments? I see they also have a belt drive kit available too. Any comments on that?

I'm sure there are many other plans available for various mills to convert. I wanted to hear from some people that have experience using these mills and converting them to CNC to see if there certain mills and/or plans that are more favorable than others.

I'm looking at milling aluminum, plastics, wood, etc mostly, but would like to have the ability to cut light steel as well if I ever had the need. It would be ok if it cut steel at a slow rate; just as long as I could do it. I don't plan on using steel very much.

So if anyone has any information that they think would be valueable to me, please let me know. Including plans to stay away from, plans that are "excellent", etc.

Thanks,

-Jaime

I'm currently building a Micro-Mark version of the Sieg x2 mill to the Ron Steel plans. The plans are very well laid out. I have bought all the components and am cutting all of the mounting hardware right now. I expect to be done within two weeks. My useage plans are similar to yours with my main target being aluminum.

I got the 3 axis kit from HobbyCNC ($275 US). The other pieces I got from McMaster-Carr for about $150. The Al stock for mounting hardware is less than $50 or cheaper if you can find someone that has it as scrap. The last thing I need to do is go fastener shopping. The plans have everything listed pretty good (in-depth and complete). On McMaster Carr there was only one item that was outdated and the suggested replacement popped up on the website.

So far so good.

Rob

Allistah,
Actually, you have given us part of the equation to be able to give you some ideas. You have indicated the type of material you want to cut, but I do not see the "envelope" that you want to be able to do.
Is the size of mill you have indicated in your opening remarks able to handle the "biggest" size of material (not necessarly part) that you want to machine?
You are about to embark on a piece of equipment that you will have to live with for some time and will kick yourself severely if you get a machine that is to small to do your everyday work.
Personally, I went the path of the mill/drill that you see so often on this list and there have been several times that I have kicked myself for not getting a bigger machine to begin with. It would have cost me about the same to cnc a full size bridgeprot as it did to do the mill drill! Yet I am limited to a fairly small set of axis movement especially in the Y axis when I throw that 6" vice on the table and try to mill a piece and hit a limit switch:(
Just my .02¢

Thanks for posting guys. I plan on using this machine for hobby purposes. I have two of those 3 axis HobbyCNC boards now. One I have used for my micro mill that I just finished for milling out PCboards. The pics are here: http://www.pirnie.org/gallery/view_photo.php?set_albumName=album20&id=Pictures_027

I don't have a lot of room so I don't want a full size mill. Well, let me rephrase that, if I had a bigger mill, I'd want it on some kind of casters so I could move it around the garage and I wouldn't want to use any special wiring for it so that would limit me to standard 110v plugs. I just don't want some huge beast that is stuck in one spot in my garage. I'd want to be able to mill the biggest envelope that I could while keeping within those mobile and power restrictions. I don't want to spend $1k either, but then again, I don't want to be kicking myself wishing I would have bought a bigger machine either so I guess $1k isn't out of the question.

Crap, I guess I could go to a full sized mill. I don't ever want to regret anything with a smaller mill and wish I would have bought a bigger one.

Ok, so now that I would go with a bigger mill, any recommendations?

Does that answer the questions?

Again, thanks for taking the time to help me out.

-Jaime

Jamie,
Ok, now I have a better understanding of your limitations and it sounds like the original proposal may be the best solution for you at this time!

I wish you the best and as always, let me know if I can help.

I was talking to my brother about this and I asked him "Where do I stop?" when it comes to choosing a mill so that I won't be kicking myself that I didn't get a bigger one. I still don't know what I want to do. *sigh* Does everyone go through this?

The way I looked at it was that if i talked myself into a bigger mill and saved up for it and by then talked myself into a bigger mill and saved up for it and then talked myself into a bigger mill and saved up for it... well anyway you can see where that is going. I got a Micro Mill to play with along with working on a router. The micro isn't the smallest work area around, although it is pretty small, but it is cheap and I already had tooling for it, so I figure I can cnc it and get the experience plus the machine however limited it might be and alot of the parts will be interchangable as I step up to a slightly bigger machine...

I would go with the biggest work area you can afford that is not absurdly oversized for any current ideas you have.... even if you have money left over from purchasing slightly smaller i guarantee you will still use it. tooling, supplies, etc

....I want to do. *sigh* Does everyone go through this?

Yep!

I'm not sure what your physical size limitations are as far as you work space. Me I'm stuck in the cellar at the moment, so that is a huge limiation unless I build up something down there.

The bigger issue is to think about what you expect to do hobby wise. There are a huge number of possible avenues for one to pursue. Somebody into model airplanes has needs that are significantly differrent from the needs of a steam engine builder for example.

So you need to sit back and reflect a bit about what you intend to do.

As to the hugeness of say a bridgeport type mill it really isn't that bad if you think about it. The space covered is about the same as a large mill/drill on a work bench. Sure you loose the work bench but that isn't a big deal. If you end up pursuing the machining of sheet goods a bridgeport starts to look very small compared to a gantry mill big enough to handle 4x8 sheets. Either of these is way to big if you expect to work on watch size parts.

Further I do hope you give up on the idea of putting your machine on wheels. A mill should be leveled and kept that way to extremely tight toolerances. In other words use a machinest level. The only exception would be the extremely small mills that are relatively stiff for their size.

So it comes down to figuring out what you want to do and finding a mill that can handle that. Or find a smaller mill and live within its limitations.

Dave

someone asked the right question - what work envelope do you want? on the x2 mill i can do just under 7x4x2 in aluminum, mild steel, and the lighter stuff. i'm preparing to offer plans my version of an x2 cnc converison that maintains manual operation. lots of pictures and video on my site. hope this helps you. i was in the same spot when i first started. pictures helped me the most. unfortunately, there really aren't too many out there.

I was tossing the idea around of buying a desktop mill which I would convert to CNC. I've seen the plans at http://www.stirlingsteele.com/millplans.html and those looked pretty nice. Has anyone bought and used these plans? Any comments? I see they also have a belt drive kit available too. Any comments on that?

-Jaime

I haven't got an X2, although I was considering one but ended-up with an X1L [long table version] which has a larger table than the X2 [albeit at a reduction in rigidity]. I did a fair bit of investigation and regarding the X2, my primary concerns were regarding the small table size / travel, the rack and pinion Z axis and the reports of a particularly fragile and noisy spindle drive train.

Please note: There are no perfect solutions! There are drawbacks to all mills, in terms of cost, mass, bulk, performance & etc.

So regarding the belt drive upgrade from www.stirlingsteele.com, I have purchased and intend to implement their mini lathe CNC plans. These plans look very good and are recommended. I fully expect that the spindle upgrade they offer should be to the same standard.

First of all it should offer a significant increase in spindle speed which is useful for engraving or using small diameter cutters.
Secondly I believe that it offers significantly increased robustness and reduced noise.

If I had an X2, I would be getting this upgrade or one like it.

The X2 and probably most other small mills probably need better lubrication - haven't heard much about this. This would be important for regular CNC use.

I'm looking at using [head mounted] oilers feeding oil via suitable flexible plastic tubing to the slides, lead screw nuts, pillow blocks & thrust bearings and quill.
In effect the machine should be dripping with oil. If you are only intending light use, an oil can may well be sufficient.

The X2 and X1L both need a higher spindle speed than offered especially for small diameter cutters and proper lubrication [especially if CNCd!]. Regarding high speed spindles, I'm looking at the Proxxon IB/E available from www.kdntools.com [USA], Axminster Power Tools [UK].

Which ever mill you end-up buying, don't forget to strip it down, perform the ceremony of the sacred removal of the evil red [Communist] grease and remove all traces of casting sand, swarf and btw grease those gears! Applies to Sieg and related variants, may or may not apply to others.

Milling steel, ali and brass no problem as long as you take it steady.
Definitely get the belt drive kit, its well made and easy to install - not worth making one yourself.
I converted my mill over to CNC and its the best thing I did, have look here:
http://www.cnczone.com/gallery/showgallery.php/cat/500/ppuser/16732/perpage/12/sort/2
I used L297/L298 chips as the basis for the driver cards, built an opto isolation card to decoupled the PC from the power side of the drivers, found some motors on eBay and linked the X and Y axis up directly. Z axis is driven with a ball screw and purpose built mounting plate bolted to the column.
Software is EMC/Ubuntu Linux running on a scrap PC - works really well and the EMC forum is really helpful and friendly.