New BP mill vs. Used BP Mill

[Perp]

I have a basic question that has been asked a hundred times I am sure. I did try to search but I could not find anything relevant.

I am very interested in learning to machine parts and I would like to purchase a Bridgeport knee mill (Hardinge...) to teach my self on. I learn best with a combonation of hands on and research, so i am trying to decide what is best for me for the hands on part. I can (with a little work) round up the money for a new or a used mill.

My question is should I buy a used one, so i can worry less about crashing and drilling into the table; or should I go for it with a new one and not have to worry about hidden damage, inaccuracy, rebuilding costs, updateing etc.

I fabricate things from steel for roll cages and suspension parts, make tools for work and build my own trailers and truck beds. So I am mechanically inclined, metal work wxperienced, and I am sure i will not loose interest or be discourage in the learning process, so this would not be a good argument to buy used.

I have also learned the lessons of life about you get what you pay for, a warranty is worth the cost of buying new, and nothing works as well as a new tool or machine. (learned all of these from buying first a used and then a new forklift).

I definetly want full CNC.

I want to be able to machine steel, not just aluminum.

Again I am very new at this and any advise, suggestions, or criticisms are welcome and I will not be offended.

BTW, just to make sure I am not setting my self up for a suprise, what exactly does a new CNC mill cost. I have a good guess but i will wait to see what the responses are. I am also leary of import clones, as i have owned other things made by the asians from Harbor freight and while cheap, they mostly turned out to be a pile of junk
Thanks in advance
Doug

[HuFlungDung]

It might take some looking, but buying a good used mill is always the method I have used. Mind you, I'm not afraid to delve into it and fix the issues, but I do stop short of re-machining bedways, etc. Checking out that part of the machine condition is relatively easy, though.

New cnc's are like cars, in that they depreciate fairly quickly. So, it might take you a couple of years for you to get up to speed, and by then, your new machine will have depreciated significantly. Don't expect anyone to give you next to new price, when the warranty is almost up.

Having said that, the cnc mill market is kind of weird: they are worth a lot, or they are worth next to nothing. Trying to find a good cnc mill in the $20K range is next to impossible, because it will be a really beat down 'modern machine' or an overpriced dinosaur, in most people's opinion, anyway.

Knee mills are not what I would recommend for full cnc. An enclosed machine with a toolchanger is much more convenient to use. Knee mills lack (often) a large range of Z movement, unless you elevate the knee from time to time. This might be like a 6" working height range for a given position of the knee. It is possible, but selecting tooling that will fit above the job, and reach all the way to the bottom can be a bit of a struggle.

If you've got a hot product to sell, it makes sense to buy brand new (maybe $40k on up in a VMC).

If you buy used, sometimes you might be able to haggle some kind of a 50:50 warranty where the seller pays half the cost of repairs for the first 6 months or so. This might help alleviate your fears of flakey electronics. You would still have to trouble shoot and repair it on your own nickle, though, as well as crashing the machine is your own expense.

Used is nice in the sense that you don't have to worry about a paint chip here or there, or scratching the table, or dimpling it with a tool, etc. You want to buy it to use it, not worship its showroom glory.

[Perp]

What kind of enclosed machine would you recomend I look at. I have no knowledge of these and am looking for a research starting point. i should say I have seen them and watched them work, I just have no clue what is a POS and what may be a good brand. Please help point me in the right direction.

Some background info that may help you:

I want to learn on it, but as I get proficient at it I would like to already have a machine capable of producing precision quality parts.

As mentioned before I do not want to be limited to the type of material I can machine (If this is possible).

I do not really have a size or weight restriction.

I don't want to buy something I can outgrow quickly.

I would think a MINI mill would be too small, I would like a full size.

Where do I start looking?
Thank you

[HuFlungDung]

www.machinetools.com
Click on these various headings over there:

machines-metalworking
machining centers
machining centers, Vertical
Used or new, your choice

Haas is good, and you can go to their website, and learn as much as you like about running one.
www.haascnc.com.

I am only recommend Haas because you can get lots of online support from other Haas users if you run into trouble, and most everyone thinks they are very user friendly to set up and operate. I like mine a lot, and I graduated from a couple of old cnc knee mills myself. Its really not fair that you get a VMC right off the bat, you know

[phantomcow2]

A VMC is really the way to go for full blown CNC, making pretty much anything. Of course this is only worth it for a business. I'de look at a used bridgeport, they last a very long time. THe one I use often is 30 years old and I can easily still hold .0005" any dimension, its great. They are made to last. And, a used bridgeport is a lot cheaper than new. Grizzly has a few decent looking full size knees also.

[Perp]

Huflungdung,

Thanks for the links. the machine tools site has ALOT of stuff, just wish the prices were posted. As for the HAAS site, they have some very interesting looking machines and a ton of info. I am going to look seriously at there products.

Phantomcow2, how do the grizzly mills (new) compare to the Bridgeport mills (used) as far as quality for the dollar in general in your opinion? I have read both good and bad about the grizzly my self. I do think you both have me talked into a VMC though.

Thanks for the responses, anyone elses opinions are welcome too.

[lakeside]

also when you surf machinetool.com all of the pages will have a link to the complete or posted invetory of that company on the bottom of page

[phantomcow2]

Honestly, I have no idea how the GRizzly knee mills compare. They are most likely made abroad. I own their X3, but this is only a benchtop mill. THe quality is top notch in my opinion. They slack a lot on the non critical stuff. Maybe the mills closer to the top dog on theGrizzly's site are better with that too.
VMC's are great, thats what every shop now uses. I just hope you know how much they cost. Like I said, its not worth it unless you are doing some sort of business. These things run off 240v as a minimum.
Here is a typical example:
http://cgi.ebay.com/Fadal-CNC-Mill-3...QQcmdZViewItem

The newest one at work is beautiful. Its got all the bells and whistles, 35HP motor, and cost about as much as a small-medium house

[peter.blais]

I'm loving my BP series 1 retrofit I bought. Being a full time college student, this lets me tinker and run a small side business without totally busting my ass to make payments. I bought it from a guy who is very very meticulous and its probably the cleanest BP1 i've ever seen, the ways and screws are perfect.

BUT, it hasn't been all smooth sailing, the ancient industrial PC's that ran it were built into the case, and miscellaneous parts kept dying on me. First it was a couple of video cards, then a motherboard. It came with 4 spare whole PC's but the majority of them turned out to be junkers as well. Long story short, I basically ended up redoing half of the computer / electronics side of the retrofit, but hell I learned a lot about how 'nc mills work.

So, I'd say, buy used if your not in a huge panic, and aren't afraid to get your hands dirty. Just remember, this is like- working on a car, a house, and an aircraft, all rolled into one.

[NC Cams]

It all comes down to money.

A decent "starter" CNC mill for the rank beginner if you can find one used would be a Bridgeport Eztrak with 3D.

If a degreed mechanical engineer can learn to read the instructions and operate it, anyone can. Probably $10k-$15K on ebay if you can find one.

Figure a few thou for a "tune up". If you go this way, we can offer assistance as we just did ours

Next for me would be a Haas Tool Room mill. Same controller as their VMC's and 3D capable. Probably $29K-$32K new equipped to the nads.

Does pretty much ANY race car stuff you'd need EXCEPT 5D cyl head machining - might do 4 though. Hard core tubing notcher!!!

Used "value" VMC's that I'd look for are BPT's VMC800-22 or VMC1000-22. Dunno costs. They use DX32 control which is the same identical control as Eztrak only with more gingerbread - 4 axis a bolt on, Don't think 5th is possible.

Next would be Haas VMC (pick your poison). Neighbor has 3 VMC's and 2 Haas lathes and they just run. Service guy was here 1 time in 4 years.

There is NO SUCH THING AS PLUG AND PLAY ANYTHING IN CNC.

Check here for discussion before you buy ANYTHING:

Great NC controller thread - NC vs PC’s

http://www.cnczone.com/forums/showth...852#post182852

[phantomcow2]

Originally Posted by NC Cams It all comes down to money. A decent "starter" CNC mill for the rank beginner if you can find one used would be a Bridgeport Eztrak with 3D. If a degreed mechanical engineer can learn to read the instructions and operate it, anyone can. Probably $10k-$15K on ebay if you can find one. Figure a few thou for a "tune up". If you go this way, we can offer assistance as we just did ours Next for me would be a Haas Tool Room mill. Same controller as their VMC's and 3D capable. Probably $29K-$32K new equipped to the nads. Does pretty much ANY race car stuff you'd need EXCEPT 5D cyl head machining - might do 4 though. Hard core tubing notcher!!! Used "value" VMC's that I'd look for are BPT's VMC800-22 or VMC1000-22. Dunno costs. They use DX32 control which is the same identical control as Eztrak only with more gingerbread - 4 axis a bolt on, Don't think 5th is possible. Next would be Haas VMC (pick your poison). Neighbor has 3 VMC's and 2 Haas lathes and they just run. Service guy was here 1 time in 4 years. There is NO SUCH THING AS PLUG AND PLAY ANYTHING IN CNC. Check here for discussion before you buy ANYTHING: Great NC controller thread - NC vs PC’s http://www.cnczone.com/forums/showth...852#post182852

There is such a thing as plug and play CNC, you just need to pay more than your annual income for the machine

[NC Cams]

Sorry, plugging in a turnkey CNC'd anything is called "cash therapy".

Big difference 'tween that technique and plug and pray.. sorry, play.