CNC Knee mill and some tooling for $10k can it be done?

[M4RK_23]

Ok I started asking questions here about small cnc mini mills then went to bench top and now full size knee mills. I want to take my approach into cnc as a buisness seriously and it's definatly best to start big as possible. I'll start small doing 3d engravings and 3d contouring small bits like dealer buttons to get aquainted with software and machine. Then I have avenues at making gun parts and motorcycle parts for a couple people so getting work shoundn't be a problem. I have a $10k allowence for machine and some getting started tooling like a clamp down kit and some bits maybe a vise should be about all for now. PC and software is no problem I already have a more than capable pc and laptop and software is whatever I want I can get don't ask how. I would perfer to run from a laptop if possible as my mill will be in a unheated shed only to be heated when working keeping a pc out there wouldn't be good. On that note having a machine in a shed with a plywood floor supported by 2x6's I'm not sure if it could support a 2-3000 lb machine. I could cut out the floor and pour a slab but would perfer not to. So I'm in the market for very good condition used knee mill to either do a conversion or update an already cnc equipted mill. I not really not familiar at all with what to look for in a used mill and further more what parts to use and how to do a conversion. I am a very mechanically inclined person so if you guys can explain it I can do it. I want a nice as possible machine as I can get that I can run from a pc, 220 line, and be able to cut perfect circles and do 3d contouring with zero backlash. Ok I'll ramble on some more after you guys give me some input. Thanks -Mark

[M4RK_23]

opps didn't realize I put this under bench top maybe someone can move it for me.

[trevorhinze]

I bought my benchtop cnc mill complete from Chris Rosequist at (cnctools.net) about a year ago for a little over 5 grand and I have been very happy with it. I know he is also selling knee mills now and I am pretty sure that the price complete is under 10k. His website is still under construction, but it has some good info and pictures along with contact information. I have no affiliation with him at all, besides the fact that I am a happy customer. I have been very pleased with the quality of my mill. I think all of his mills feature servos/ballscrews/Gecko drives/Mach 2 software. Good luck with your search.

[M4RK_23]

theres a decent looking cnc bridgeport on ebay $10k a little steep on my budget but probably worth it. http://cgi.ebay.com/ws/eBayISAPI.dll...MEWA%3AIT&rd=1

Then there are a few various manual mills for under $5k perhaps one of them could be converted for less than another $5k? like this Jet mill http://cgi.ebay.com/ws/eBayISAPI.dll...MEWA%3AIT&rd=1

There a a couple small jets also maybe more affordable. I'm looking for quality like the tormach has but with a bigger envelope and keeping ease of use on a pc with cam software also like the tormach.

[tpworks]

Check out this mill .

http://industrialhobbies.com/

[wizard]

If you are seriously thinking business here then cash flow and the feasbility of running the products on smaller machines has to be taken into consideration. For example if you expect good sales rates for custom dealer buttons then you will want a machine sized well for that. While well out of your price range something like a HAAS office mill OM series might be very productive in that sort of application. That is engraving and machining plastics with small cutters.

What I'm trying to say is that you mentioned a few products that may require differrent hardware (machine tools) to allow you to compete effectively in the market place. For example the above mentioned mills might be good for engraving a gun but would likely perform poorly machining components for a firearm. A good argument can be made that a CNC toolroom mill such as a HAAs TM might be a good start for a business. I'm not sure if you follow what I'm saying but what you intend to do with the machine dictates what the machine will be.

The other issue for business purposes is that the machine itself is only a small part of the startup experience. Or maybe better said only a smallpart of where the money goes. Raw materials, development time, expendable tooling, instruments, software all enter intot he equation.

As to the conversion mills you are looking at there are likely to be good deals out there, I haven't looked so I can't say. The problem you have to address is will the spindle on one of these mills do what you want or will you need to adapt it for the dealer buttons. I ask this because I suspect that the finished apperance of the part is extremely important. I fully understand that you could always clamp a high speed spindle onto the mill for this specfic project but it could be seen as a hidden costs.

So back to the size of the mill. Yeah a bigger mill has advantages especially if you get into alot of varied work, but going to big can work against the finacials of the business. The idea is to make money of course, so is it reasonable to spend $10000 on a machine to spit out dealer buttons if that is all the money you have to invest in the business? I'd say no myself.

I'd consider two things. One would be a low cost machine that you build up from a new chinese machine. This machine would be designed to handle your dealer buttons primarly. The other idea is to find a used CNC mill with a high speed spindle and start up your business that way.

Thanks
Dave

[M4RK_23]

The dealer buttons are really more less a joke as for a long term buisness avenue. Ya if all I were going to do would be thoese I would get a quality router with high speed spindle. While I may make some money from them as a start it will only be till I figure out what I really want to do. I guess it's really not reasonable to buy a mill before you know what you really want to do with it. If I can get into a decent knee mill say 9x49 that can be cnc fit with high quality parts like ground ball screws with double ball nuts making a really good zero backlash system then although I may only use it to make little acrylic and aluminum buttons now. I'll be able to down the road make things like custom clutch covers or scope rings things that demand real precision. The tormach is very nice and at the kind of quality I want but some of you suggested I could get a used knee mill of equal quality and retro fit it or just replace some electrinics and end up with a better bigger machine. So I agree and would like to try that. I know it seems like I'm not thinking about enough tooling and such but there will be more money for that above the $10k. The $10k is just a figure for what I'm able to spend on a mill and some very limited tooling for now like the tormach cnc tooling system 20 or so end mills clamp down kit maybe a vise. I have some calipers and software is not a cost problem acrylic and aluminum are cheap materials to get started with and practice on. If I thought all I would end up making is small parts then I would just get a tormach it would even be good for small gun parts like scope rings but what if I end up wanting to make something big like clutch covers then I'm stuck with an incapable machine where if I had a bigger mill I may just need to get more tooling for a special task. Thats why I want to get as big of a mill as possible so later when I want to do something all I may need is more tooling. Thats all I can think of for now so lets see where that get me and go from there. Thanks -Mark

[wizard]

It almost sounds like you have two interests. Specfic products you want to make such as the dealer buttons and scope rings and more or less parts that might be associated with a job shop. If you are just starting out then it would be best to have amachine that can be used well both manually and as a CNC machine. Manual can be read as manual like the old days and also as a CNC controller that allows for easy manual use.

As to the engraving of the buttons this is not impossible on a metal working mill with limited spindle speeds One could simply attach an air driven spindle to the head stock. Or some other speed increasing device, assuming that you have the horse power. This would give you the ability to use small engraving and machining tools on the plastic buttons. Yeah it is an additional expense but you will still have a CNC machine at your disposal for metal work.

As to the actuall machine figure out how much you are willing to invest in your products. From that take awy the cost of materials to produce them, the start up cost of materials and fixturing and any other cpaital requirements. Give your self some buffering cash wise and see how much you have left for the machine. I'm willing to bet it won't be much.

That is one way too look at it, many would suggest that the capital equipment would best be fiananced over time. I'm going to suggest that you don't have a business plan for that yet. This would free up some ofthe cash up front for more business related items, not the least of which would be marketing these products. Marketing would be huge for things like the dealer buttons as I see the real money there being in custom products, which would be difficult to sell over E-Bay. In any event as mentioned below I don't see a busness case for fianacing approval.

As to the "as big of a mill as possible" I think that attitude is clouding your business sense a bit. Rather think about what you want to do and get a mill that can cover that demand well. To large a mill and you will never be able to cover the expense of keeping and maintaining it with your products. Some of the items you mentioned would be very compatible with a smaller CNC mill and if produced in high enough quanities could be very profitable. Produce enough profits at startup time and you could easly expand your operation with a larger machine for future endeavors. Get saddled with a machine that causes huge debt and is not productive for the parts in question and you end up selling out three years down the road wondering why you never made any money. This is why I believe that your best bet is a really small used CNC machine, assuming that you have the ability to power it.

Thanks
Dave

[M4RK_23]

Well my dad is a maunfactering consultant and yesterday he talked to an engineer at one of the places he goes to and he advised to not buy a used machine. He said they have done that in the past and it took a few months to get it running cause so much work needed done. So it looks like my only route will be to go new which leaves me in the bench top market.

[wizard]

Well buying used does inply that you are able to determine the state of the machine. The number one issue beign tht it runs.

I don't really want to get into the specifics of buying used as that is rather hard to do over the net. What I do wnat to point otu is that there are at times many machines available n the market that have vey low hours on them. Machines from schools, research labs, government installations, too and die shops and others can be in very good condition. The other thing to realize is that numerous shops have gone out of business recently and as a result machines are hitting the market place in good condition and reasonably priced.

I don't dis agree with your fathers contact, you can end up in a world of hurt buying used. The thing to realize though is that the market is signficantly differrent now than it was even two years ago. A reasonable person would not discount the possibility.

Now as to doing a retro fit or home building a machine, that is not out of the question either. I happended to be at Cabin Fever this weekend and had the good fortune to talk to a gentlman that had started his business with a home built CNC machine. He now has two HAAS CNC machines plus he is farming out work to a local shop. This to support customers world wide. So you shouldn't be discouraged going the home built route either. The cases of success are out there.

The only problems I see with a retro fit is that it is a good deal of work, maybe even more so than getting a used machine up and running. Not only do you have to buy and integrate the CNC hardware, you have to deal with the mechanical nature of these cheap machines. You could easily spend as much time on a doit yourself conversion as would have been spent on a used machine. Do consider a kit or a already converted machine to shave a lot of time off the project.

By the way Cabin Fever was excellent if not a bit crowded this week end. There were several companies demoing various CNC hardware. One to look out for is PMDX, they have a very nice way to integrate Gecko drives into a CNC controller. There was also another venodr there with an X3 conversion system, unfortunately I did not get much in the way of documentation from either.

Thanks
Dave

Originally Posted by M4RK_23 Well my dad is a maunfactering consultant and yesterday he talked to an engineer at one of the places he goes to and he advised to not buy a used machine. He said they have done that in the past and it took a few months to get it running cause so much work needed done. So it looks like my only route will be to go new which leaves me in the bench top market.

[wizard]

Hi Mark

As I posted in another thread I have forgotten completely about one alternative you may want to consider. Smithy has a new CNC mill that is apparently ready for sale. I saw the prototype at NAMES and I have to say it does look nice.

This is not a knee mill at all. It is a small / light mill designed for CNC from the begining. It is certainly worth looking into, if you are willing to go with a machine of a completely new design. Small is realtive to a full scale CNC machine, capacity wise it seems to be rather capable.

Dave

[Cycle Start]

Hello

I saw a cnc knee mill on ebay in January price seemed low. At last minute put in the winning bid. I knew there would be tooling, electrical, and misc. costs, but I was sure suprised.

First, my incomming service was underpowered to begin with. Once the electric company engineer gets involved he wants to know everything that I want to run(house and garage) he doesnt care what it is he just wants to supply me with enough amps. He determines that i need 400 amp primary service(200 house/200 garage). I am thinking this is great I will have enough power for future machine additions. Where the costs come in is that it is my responsibility to install everything from the incomming primary wires. By the time I was finished I had $1500 in wire, 400 amp meter socket, and new service wires to house and garage. Add on to that i had the cost of a phase converter $700(10hp american rotary works excellent).

You will want to keep heat in your shop to some degree. CNC machines have much the same electronics as computers. I would not put a machine anywhere I would not be willing to put a PC

I hope this helps
Joe