How do People Find Used CNC Machines That Are Worth Buying?

Chips O'Toole

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Every so often I get the urge to get a CNC mill, and then I forget about it, because new ones cost a great deal of money and I don't know how to check out a used one.

When people go to forums and ask for opinions on low-cost machining centers, someone usually says, "Instead of buying that toy, you could spend less and get a used Haas." Something like that.

Here is my question: how is a person who is new to CNC supposed to be able to tell the difference between a good used CNC machine and one that is being unloaded because it's hopelessly obsolete or no longer able to do good work? My bet: the very suggestion is totally unrealistic.

Sometimes people say, "Make sure you take an experienced friend to look at it." That's great, but most noobs don't have any experienced friends, and you can't really go out and make a friend just to get a machine looked at.

It's bad to spend $30,000 on a new machine, but it's also bad to spend $7000 on an old one that doesn't work very well!
 
Sometimes people say, "Make sure you take an experienced friend to look at it." That's great, but most noobs don't have any experienced friends, and you can't really go out and make a friend just to get a machine looked at.

While I agree that going out to "make a friend" strictly for the purpose of appraising a machine for you would not be a good thing.....Ending up with a Friend after the fact around different circumstance Would not be objectionable!
Hit up a few of the local machine shops and ask around to see if anyone would be interested in helping out for a few bucks. Invite them out for a drink at the local watering hole to chat them up in a way to evaluate their knowledge, get to know them and work out the details for the job. I dont think it would hurt to try and like I said, you may just end up with that Friend and a new to you cnc mill!
 
I don't own one but I'm thinking there's two reasons why people get rid of them- the electronics and software are obsolete and clunky and/or the machine is physically worn to the point it won't do super accurate work anymore. Neither of these reasons may be a deal breaker for a hobby machine. You may be able to retrofit the electronics and the accuracy may be good enough for you. Depends on what you want. You obviously won't get a like-new machine for a fraction of the cost, but you might find a "little old lady who only ran it on Sundays" type of deal.
Mark
 
I get tempted at almost ever auction I go to. Majority of the ones I see don't sell and go to a machinery wholesale place. I do see some get loaded on trailers going to Mexico but for the most part their arnt bids on them. New business most likely won't buy, to big for the average hobbiest so they sit. If I had the room I would be dangerous! Maybe one day. A tip at least for auctions is if the place is closing cause the owner is retiring most likely the equipment is old and worn, if it's out of business because of business or else relocating equipment is usually good And current.
Trying to find someone that runs or ran a machine your interested in is a good idea but can be a challenge finding. If really serious I would call a service tech from that manufacturer and get a service call evaluation on auction inspection days. The money saved from a auction purchase I could pony up a 500 dollar service call on a 5k purchase for a 40k machine.
 
You are correct that it's very risky. One little mishap, and you can end up spending a lot of time reverse engineering an orphan. I soon will be able to speak from experience. Almost there.
 
What size are you looking at? There's every thing from desktop "CNC Routers", Benchtop CNC's built on Dovetail Ways, to Production level Haas's.

I have a Syil X3, which was built on the Sieg SX3 castings. Ball screws and dovetail ways. Fits my needs as a hobbyist. Not fast by modern cnc standards, but fine for my non production uses.

There are a number of kits to convert various manual mills, if you want to build your own, (and then you'll know the condition of your machine).
 
I'm sure if you do your research, and are patient you can find what you're looking for. One of the biggest limiting factors with used machining centers is even if you have the space do you have the power to run it?

There are plenty of folks on this site with production experience who I'm sure would be glad to help, there was even one member a little while back who was trying to find a buyer for machines his boss was selling.

Like looking for any used machine patience is your friend. If you know exactly what you're looking for, and what you are willing to spend you'll get what you need. Read Jim Dawson's threads if you want to know about retrofitting new controls into an older machine, it can be done and good machines can be had for a bargain if you are willing to put the work in.

Cheers,

John
 
Yes, I basically did what Cadillac and matthewsx said. Be patient. Be ready. I'm sure every situation is somewhat unique - I will share my experience with this.

I was several years in the place where is seems you are - "wouldn't a CNC mill be cool?" I agree, a decently capable hobby machine is still quite a bit of coin. In those several years, I got a number of the potential issues sorted out:
- I built the larger shop space. It was not specifically for getting a CNC mill, I built because I had some machines and I wanted to get some more machines, I wanted more work space etc.
- I knew that power would likely be an issue. The old RPC had served well, but I really couldn't run the high speed motor setting on the lathe (the RPC overload tripped on ~2nd start in a couple minutes). A power upgrade would be nice.
- I had a number of transport options sorted out - depending on what came along.

So I started asking people about CNC mills. I put the word out. I looked at a few machines. I found out that in my area, old CNCs are very difficult to sell (too large, heavy and hard to power for a hobby setting and issues with obsolescence or even minor glitches and the productivity of new machines means that a commercial operator won't touch it).

I got a 20 year old 4 axis VMC 1000mm in the x-axis - it has all the stuff (enclosure, flood coolant, ATC, conveyor, auto lube, a decent tool selection). The move was easy (simply $$ cash), the power upgrade cost as much as the mill + moving it. The machine was local to me - easy to look at and still under power. The machine had a number of issues that turned out to be minor. The programming (G-code) is challenging, but not insanely challenging - I read lots, watch the videos, try stuff - works fine.

For the price of a modest hobby machine (the all in machine + moving it + powering it and necessary repairs ~$17K), I now have a very capable industrial machine. Of course there is plenty more I could buy for it (and probably will) - but to date I have been thrilled with the results. It has been a great learning experience and brought about a whole new bunch of opportunities. I have two good manual mills (powered, set up, well tooled), now I rarely touch them.

Let us know how you make out. David
 
 
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