Vertical Mill for FRC

[FrankJ]

Getting a mill with digital readouts (DRO) is worth the extra money.

We have a Enco value priced mill with DRO at the build site. Within its limits it does better than my heavily worn Bridgeport at work & takes less skill to use. The skill part is knowing how to compensate for the wear more than one machine being easier than the other. We also have a 1940s vintage Southbend 9A lathe . I am really fond of it, but having it to do over again, I would have bought a new value priced lathe. While it nice to have industrial quality tools, you are not putting the same hours on them as commercial facility would.

Most of the small mills & lathes can run on less than 1 hp which means single phase 110 or 220 is a possibility. Best with a dedicated circuit though. You can get a single phase VFDs to convert to 3 phase if that is what the motor is.

[Teamcodeorange]

Originally Posted by sanddrag

3476 Code Orange has a very similar (if not identical) mill to the Grizzly one linked, and they're pretty close by to you. I bet they'd be willing to show it to you.

Yes. We do have one, however I can not recommend this model. It worked okay during the season, however it is prone to breaking and is cheap in general. Go for a used vertical knee style milling machine instead.

[kellymc]

Check out the Seig machines offered by DRO pros as well, you can also get a DRO from them at the same time

[kaliken]

To add to the discussion.

Yes, buying a nice knee mill is good and likely a great option if given the chance. 294 has been extremely lucky that our main sponsor Northrop-Grumman has donated a couple of old Bridgeport knee mills for our shop.

However, I totally hear the things that need to fit in the shop. While our build area was under renovation in 2013 we were displaced into a portable classroom. Realizing we have lost our machining resources and we didn't want to use up all our sponsors time to make tons of brackets or spacers, we purchased a mini-mill and lathe. Namely a G0704 and an Micro-Mark 7x16 lathe.

For all the crap people spout on them, they were a godsend to our team.

Now I will be honest, the lathe turned out to be more of a dud. The tail stock was poorly designed and couldn't maintain alignment even after being trammed. We had to do a lot of adjusting to get the lathe up and running. The mill was absolutely great. Are you going to cut giant pieces while maintaining 1 thou tolerances. no. could you cut simple brackets with semi- tight tolerance holes? actually yes; even without a DRO (we actually taught kids about backlash and how to compensate) you could machine some pretty decent things.

But the biggest thing, was that these little machines turned out to be super student friendly and turned into major workhorses during out 2013 build season. We would have never survived without them and I feel that getting one is not a bad idea. The big caveat is that you need to give them a little bit of TLC. Spend the time disassembling, tramming and dialing things in. Just like you need to do on any machine, a little will take these machines a long way.

Also.. to make things even more interesting. Once we moved back into our normal build space, we decided to convert our G0704 to a CNC. With a little help with the home machinist community and the huge amount of online resources we successfully turned out a pretty nice little CNC machine. Obviously its not a HAAS VF2, but it seriously churned out every bracket, gusset plate and heck even our custom 3CIM gearboxes. Heck it got just as much use as our standard Bridgeport machines. Not too shabby for such a small mill.

[magnets]

Personally, I'd avoid getting any Grizzly tools. They really are crap. My experience is that they fall apart, have manufacturing defects, and are really weak/sloppy. A higher quality mill will be much, much more rigid.

Get a bridgeport, it's really worth it. If you can't get any 220v power, use a VFD converter. A DRO is really nice to have, but not 100% essential.

As for tooling, try asking local companies. We get an incredible number of reground endmills in all shapes and sizes from our sponsor once they have been reground too much and no longer meet their spec, but they work just fine for us.

If you don't have a lathe, I might consider getting one before a mill, but that's just my opinion.

[Cory]

You can polish a turd and you can make decent to good parts with a crap machine, but there's really no objective argument that the mini mills sold by grizzly (and most other rebadgers of Chinese equipment) are not somewhere between bad and terrible.

Having the ability to spend a bit more money makes a huge difference in maintainability, ease of use, resistance to damage by novice users, and lowers the amount of effort required to produce good parts.

[Mr. Mike]

Machinery Parts Depot has a kit for $500 to convert a Bridgeport to single phase power. Its hard to beat a knee mill for flexablity.


http://www.machinerypartsdepot.com/s.../product/SP2SP

[Tristan Lall]

Originally Posted by Mr. Mike

Machinery Parts Depot has a kit for $500 to convert a Bridgeport to single phase power. Its hard to beat a knee mill for flexablity.

Surely a VFD with 3-phase output is cheaper than that? (And less annoying than having to modify the pulley.)

[kellymc]

I mounted a 1hp 90V DC motor on my knee mill, with the speed controller on the wall, instead of changing pulleys I can dial in my speed

Kelly

[CENTURION]

Originally Posted by Tristan Lall

Surely a VFD with 3-phase output is cheaper than that? (And less annoying than having to modify the pulley.)

Yeah, a VFD like that is like $150. Plus you get easier speed control (easier than step-pulleys anyway.

[Qbot2640]

Originally Posted by kaliken

Also.. to make things even more interesting. Once we moved back into our normal build space, we decided to convert our G0704 to a CNC. With a little help with the home machinist community and the huge amount of online resources we successfully turned out a pretty nice little CNC machine.

I'd love to see some information about this...want to eventually do the same thing with ours.

[George C]

Try industrial auctions. Some are bankruptcy/liquidation sales and some are just a method of selling surplus equipment. A quick google search for huntington beach industrial auctions gave several hits.

[protoserge]

Originally Posted by Qbot2640

I'd love to see some information about this...want to eventually do the same thing with ours.

http://www.g0704.com/G0704_dvdrom.html

[kaliken]

Originally Posted by stinglikeabee

http://www.g0704.com/G0704_dvdrom.html

Exactly. This is pretty much where we ended up. Hoss has been super helpful to me and to many others. He is quick and responsive to emails and is willing to help out.


There is a ton of info and several knowledgeable people at cnczone as well.
http://www.cnczone.com/forums/benchtop-machines/

For the electronics we ended up going to
www.cnc4pc.com

The owner Arturo Duncan was super helpful. And he knows all about FIRST as his daughter was part of SPAM's 2012 championship team!

For the control, we had an old PC that we put Mach 3 on. I would recommend getting the Ethernet smooth stepper as it made life super easy not to have to deal with the parallel port.

For the CAM we use HSMworks. if you contact the development team you can request the full version. You need a teacher to do this as they need to be registered through a school district or university. They also have the post processing files for Mach3 so we were able to make chips pretty quickly


As for the conversion. You learn an awful lot about the machine. From tear down to reassembly, you will get to know its weaknesses and strengths. Understand that there are limitations on the machine. Set expectations on what you want out of it. Like I said above don't spend time trying to turn it into a HAAS. It just wont get there.

For us, it turned into a great little machine in which we plan to use to get our students into CNC machining. Thus our students can see and experience the work that goes into making a CNC part, rather than send the part out and the CNC machining fairy brings something back. For future builds we will do simpler parts in house now and send complex parts to our main sponsors.

Best of luck

[AdamHeard]

Originally Posted by kaliken

Exactly. This is pretty much where we ended up. Hoss has been super helpful to me and to many others. He is quick and responsive to emails and is willing to help out.


There is a ton of info and several knowledgeable people at cnczone as well.
http://www.cnczone.com/forums/benchtop-machines/

For the electronics we ended up going to
www.cnc4pc.com

The owner Arturo Duncan was super helpful. And he knows all about FIRST as his daughter was part of SPAM's 2012 championship team!

For the control, we had an old PC that we put Mach 3 on. I would recommend getting the Ethernet smooth stepper as it made life super easy not to have to deal with the parallel port.

For the CAM we use HSMworks. if you contact the development team you can request the full version. You need a teacher to do this as they need to be registered through a school district or university. They also have the post processing files for Mach3 so we were able to make chips pretty quickly


As for the conversion. You learn an awful lot about the machine. From tear down to reassembly, you will get to know its weaknesses and strengths. Understand that there are limitations on the machine. Set expectations on what you want out of it. Like I said above don't spend time trying to turn it into a HAAS. It just wont get there.

For us, it turned into a great little machine in which we plan to use to get our students into CNC machining. Thus our students can see and experience the work that goes into making a CNC part, rather than send the part out and the CNC machining fairy brings something back. For future builds we will do simpler parts in house now and send complex parts to our main sponsors.

Best of luck

We've had a similar experience.

Made a decent size metal router, fixed up a 2x2 wood router than 294 (thanks!) gave us years ago, and recently converting a full size knee mill.

I know you like your little machine, and your points are all valid... but I think everyone would agree that the biggest (And closest to full size machine) you can get, the better.

Certainly that machine versus no machine is AWESOME though.