IH vs. CNC masters

[dlenardu]

Hi everyone,

I would like to get everyone's opinion. I am looking at the IH cnc mill www.industrialhobbies.com and the CNC Masters Supra Mill www.cncmasters.com They are both about the same money. The IH uses servos and Mach3 where the CNC masters uses Micro-Steppers and their own software. I like that the CNC Masters can also be used manually. They also have a 5600 rpm spindle VS. IH spindle speed of 3600 rpm. I am mostly machining aluminum and a little bit of steel. I machine decent size parts. I like both machines, the travel size is right (using IH's travel extension) but my biggest concern with the IH is the spindle speed. A couple of parts that I machine have a 2mm o-ring groove in them so I need high rpm for this. What are your opinions?

Thanks

[DRD]

I have no experience with ethier of the machines you pointed out. I have owned many manual and cnc machines, small to large, and will say, buy a machine that you will be able to use down the road so to speak.
It seems that we buy a machine, you say months later, man I should have got something bigger. The purchase all depends on how much money you can spend. But for example, for 10k, you buy a new small machine, most likely with steppers motors, or buy a older vmc, or knee mill conversion, with servos. Look at the big picture down the road. IF I knew what I know now 20years ago, I could have saved myself alot of time and money for sure.
Good luck on your machine purchase.

[pzzamakr1980]

Well, mach3 cannot be beat. There is a reason it has become the gold standard for hobbiest and light production work. It comes standard with Tormach and almost any other cnc'd mill that would fit the hobby genre. As far as the spindle rpm goes, take a closer look at what IH offers. They have a vfd and a motor that will push the spindle up to where you want. Just talk to Gene at IH and he will tell you. After purchasing some parts from them for my X3 (optical limits), and experiencing firsthand the level of customer service and the beautiful well made product that they provide, Im already saving up for my IH cnc mill. Also, a mpg from candcnc or LMS will easily provide you with that manual feel for very little money. The last remark, look at how the z axis is done. The cncmasters supra mill only drives the quill which means severely limited z travel and a possible lack of rigidity.

[all4anm]

We bought a CNC Maters Jr. last year. I've been very dissapointed.
The software is very limited and hard to work with. You can't pause and rezero a new tool then continue. Every tool will need a separate program. They have told us that they have no plans of updating their software.
As far as using the machine manually, Good luck. You have to disconect the motors from the controler, and there is no way to measure your movement. How it actually works I don't know. Never tried.
There is also about a quarter inch of play in the z axis were it only uses the weight of the spindle to plunge before the motor forces the spindle down. It took me 6 months to figure out why my drill holes didn't go as deep as I wanted. When I asked them how to fix the problem, they just said it is what it is. If this problem exists on the full size maching I don't know, but I wouldn't doubt it.
I don't know anyhthing about the other machine, but I would think twice about the cnc Masters machine.

kl

[mcarvey]

I've never used a CNC master's mill before so unfortunately can't give you too many helpful comments about them.
I have been using the IH mill with CNC kit for around two years in a non-production environment and have been pretty pleased with it. I have an older version and I hear that the newer versions are more rigid and have a few more features. Most VFD's can output a drive frequency greater than 60hz and the limiting factor is typically in the motor/gearbox/spindle bearings. Definitely call IH and ask what the upper limits of spindle RPM are. They use their machines to make all of the kits so they know how much they can squeeze out of them. I've called them on a few occasions and have been pretty happy with their customer support. IH also offers to show people their shop to anyone who is interested. If you're willing to make a trip to Connecticut, you can watch the machine in operation and get to know its capabilities/weaknesses before you drop ~9K on it.
One thing that I do like about a large tabletop mill is that you can put it on a big table with a basin, and flood coolant doesn't get all over the place. I haven't used a knee-style CNC'd mill with flood coolant so I don't know how much of a problem it is.
Since I've never done manual machining on a mill that has ballscrews on it, I don't want to jump to too many conclusions. One of the big reasons that they put ballscrews on the machines in the first place is to get the drive efficiency up. By definition, this means that they are able to backdriven fairly easily. I suppose if you're taking really light cuts this may not be a problem and I think they used to do that on some of the Bridgeport EZ-track's so I'm not sure how big of a problem it is.
I know you aren't looking at the CNC Jr, but I have a mill/drill that is a very similar design and don't think it would be suitable for CNC.

I hope this helps,
Matt

[dlenardu]

Guys,

Thanks for all of your input. I will give IH a call when I get back in town