CNC Router/Mill

[Andy L]

We are in the process of hopefully getting a grant from our school district. Today our teacher told us that we need a list of tools that we want by tomorrow, after searching for a while we have failed to find what defines a good CNC Router or mill(still not sure what the difference is,sorry) so we decided to take the easy way and go to reliable Chief Delphi for a place to buy a good CNC mill.

[sanddrag]

Budget determines everything. Have a number?

[Andy L]

apparently its like $100,000 but we're going for a midlevel CNC. A nearby school got $20,000 for theirs so we're expecting something around that maybe a little less

[Cory]

$20,000 is right in no-man's land between benchtop mills, converted knee mills, and full blown machining centers.

Does that include tooling? You're going to spend at least $5,000 on tooling.

[bwobo]

Ok well for something a little better, what would you suggest? There is a meeting being held soon where our school needs to tell the district what we want. We will include tooling in final costs. Within $20,000-$40,000 (including tooling) what would be suggestible and most advantageous.

[Doug G]

We went with a CNC Jr from CNC Masters (www.cncmasters.com). The control software is a bit buggy and irritating, but now we've played with enough to figure out how to best use it. The whole setup is less than $10k, so you get what you pay for. They're located in SoCal, which is nice and they've been very helpful by phone with any of my needs and questions. Last year, during build season, we blew out a control board when the power to our building went out (yes while the CNC was running). I packed up the control board and sent it to them on a Thursday and had it back the following Wed. Not bad service!!

We've become better with MasterCAM, which is a really cool tool that can speed up and expand your capabilities on a CNC - so don't forget to add on a license or two for that. I think you can get a edu version for about $1k.

There is also microkinetics which has some really cheap CNC offerings. I have one of their desktop mills which will do a lot, but it will do nothing fast and nothing that big. I've made transmission plates on them, but you have to do 5-6 passes for 1/4" aluminum - YAWN!!

Good Luck.

[bwobo]

Thanks for the help. Yes, we would want something consistent, reliable, and efficient....(obviously), but, I will look into that. I know I still have a lot to learn about different specs and such. What kind of range is good to have on an X,Y,Z axis? And, what kind of rotary table, in the sense that, I have seen different options on them, like detachable, 1 degree, etc...?

[Cory]

Originally Posted by bwobo

Thanks for the help. Yes, we would want something consistent, reliable, and efficient....(obviously), but, I will look into that. I know I still have a lot to learn about different specs and such. What kind of range is good to have on an X,Y,Z axis? And, what kind of rotary table, in the sense that, I have seen different options on them, like detachable, 1 degree, etc...?

I think a rotary table is a bit beyond your spending range, if you want a solid CNC mill that will last the lifetime of your team.

We got one with our VMC last summer, and it totals about $10,000 from Haas. We have yet to even use it. It's nice to have, but not a necessity. You can always put a manual indexer or rotary table on your mill. Odds are any 4th axis work you do is indexing, not contouring.

[Doug G]

Update to my other post, now that I saw the budget... CNCMasters has a Supra CNC which is a more familiar bridgport like knee type mill. A big package is around $10k, add a bunch of tooling and extras (MasterCAM) and you'll be right there around $20k.

[Cory]

I'd go for a Haas TM-1

You'd be getting a very versatile machine--something with a lot more power and speed than a knee mill, or a benchtop machine. It has the advantages a knee mill has, in that it's got a large table, is familiar (mostly) and can be operated via handwheels, just like a manual mill.

We have a Haas VF-1, which is a machine geared more towards production, but it has the same control. The Haas control is very easy to use, and comes with templates to help you write code, and "quick code" that you can program most simple parts just by entering values into data boxes.

Out the door you're looking at somewhere between $28,000 and $36,000 depending on the options you choose. Haas offers a educational discount as well, I believe. Probably 5-10%.

For tooling I'd say you're looking at around $4,000-$5,000. You can spend a lot more, or a lot less, but for tooling that will actually take advantage of the capabilities of your machine, I'd say around $5,000.

There's a lot of variables to consider. I spent a LOT of time researching every manufacturer out there when we were going through this process. Literally months of time sorting through all the information out there. It can be very daunting. Let me know if you have any questions. I'd be happy to help you out.

[edit] as Doug says, be sure to budget for CAM as well. You can't run the machine very well without CAM. We use MasterCAM also. I've tried CAMWorks and GibbsCAM, but I find MasterCAM the easiest. I think it is right about at $1k for an educational license like he mentioned.

[bwobo]

Ok thank you very much for help/suggestions. Yes just from a lot of personal research I have done already I can tell the the extent of research that is good to have. I will definitely keep in touch with questions as they come up. One thing I saw on the TM-1 is an option of CT or BT taper type, what do those mean?

[Cory]

Originally Posted by bwobo

Ok thank you very much for help/suggestions. Yes just from a lot of personal research I have done already I can tell the the extent of research that is good to have. I will definitely keep in touch with questions as they come up. One thing I saw on the TM-1 is an option of CT or BT taper type, what do those mean?

CT taper is common in the US. BT is in the rest of the world.

The short answer is they are interchangeable. As you are in the US, you'll buy a CT taper because it's the standard. The actual taper on the toolholder/spindle is identical. The only difference has to do with the drive dogs on the spindle face, and the thread on the rear for the pull-stud is metric on a BT holder.

[bwobo]

Ok, I understand that now. I will look more in to that Haas and do some more personal research. As for tooling. Say, with the TM-1, just get tooling straight from Haas then? Because I saw in the "Build-a-Quote" you can add on tooling like CAT-40 Tool Package. for $2100, as well as 24 Pull Studs (CT40) for $300. Would that be advisable for tooling? And possibly any other accesories to help make it a complete and long-lasting system? Thanks for all of your help so far!

[artdutra04]

Originally Posted by Cory

I'd go for a Haas TM-1

You'd be getting a very versatile machine--something with a lot more power and speed than a knee mill, or a benchtop machine. It has the advantages a knee mill has, in that it's got a large table, is familiar (mostly) and can be operated via handwheels, just like a manual mill.

One of the dozen Haas CNC machines on my campus is a Haas TM-1, and it's definitely a good machine for doing all different kinds of work.

The best thing about it is having the ability to machine plastics (Lexan, delrin, HDPE, UHMW, etc); on most enclosed CNC machines you cannot machine plastic because it'll clog the coolant pumps. On the TM-1, since the coolent pump is "separate", you can machine plastics and still be able to vacuum off the machine.

Just remember, the TM-1 only has a partial shield around the table. So if you set your coolant pump to ludicrous speed when machining metal, then you will spray coolant everywhere, especially to the left of the machine. Most of the time you can avoid this by just adjusting to a slower coolant speed.

And one more thing. Go up in your attic, basement, or garage and dig out all those 3.5" floppy discs, like all those free ones that came with AOL 3.0. Many CNC machines still use floppy discs to load NC programs (these are the programs of G-code that tell the machine how to make your part) onto the machines; the only ones I've seen that have support for USB Flash drives are the larger models, like the Haas VM-3 or VF-4.

Originally Posted by bwobo

Ok, I understand that now. I will look more in to that Haas and do some more personal research. As for tooling. Say, with the TM-1, just get tooling straight from Haas then? Because I saw in the "Build-a-Quote" you can add on tooling like CAT-40 Tool Package. for $2100, as well as 24 Pull Studs (CT40) for $300. Would that be advisable for tooling? And possibly any other accesories to help make it a complete and long-lasting system? Thanks for all of your help so far!

When purchasing tooling, just remember that the TM-1 only has a ten-tool changer. Ordering 24 tool holders seems like a bit much.

I would recommend three (or four) drill chucks, five to seven collet tool holders, and three or four tool holders which use a set screw to hold the cutter in place. The drill chucks tool holders are useful for center drills or regular drill bits. The collet tool holders are versatile and can hold any size end mill. The set screw tool holders are useful for something like a face mill, which will most likely just stay in the tool holder.

Also, remember than one of those ten spots in the tool changer will usually be a part probe. At both machine shops on campus, we always leave the probe in T10 (the last tool spot) in the TM-1 and Haas Mini Mills, and T25 (the last tool spot) in the Haas VM-3 and Haas VF-4, which all cost in the $50-$60k and upwards range.

Also, getting good tooling can sometimes mean doubling the price of the machine. That also includes things like vises. A good Kurt vise can set you back up to $700, and if you want to machine long stock, you'll need two vises.

Then there is the question of drill bits and end mills... These start adding up very quickly.

[Andy Brockway]

Another option can be found at http://www.tormach.com/Product_PCNC_main.html. This may be a little smaller than what you are looking for but may fit your needs.