School teacher needs help

[carman]

Hello.
I am new to all of this and need some help/answers.

I have a Minitech CNC minimill/2 (made in Atlanta Georgia)that I am thinking about buying for the school. The mill seems nice but I do not know much about the software it will run. Does anyone on this board have this same mill? If yes what software are you useing? Will it function with master cam?

[sansbury]

Since no one who knows what they are talking about has responded, I will try.

From what I can tell on the website, the Minitech driver-controller will take standard G and M codes which is what Mastercam and pretty much every other CAM application will output. That's the simplest take--often you will want to look at post-processors as well and there is a decent chance there are posts available for that mill. These are used to further tailor the CAM output for the specific mill they will be run on.

The minitech looks like a very nice machine but for $7500 new I'd rather buy two CNC'd Taig mills and then the kids can make twice as many chips

Other crazy idea is to find a local machine shop or manufacturer or college to help you out with all this. Machinists are becoming extremely hard to find due in large part to the fact that we keep trying to send boys to college for degrees they don't want rather than introducing them to skilled trades that they might really enjoy.

[blackbeard52]

Carman

It appears to me that a build would be a great education tool for your students. A Joe 4x4 would serve you well for the forseeable future and if you build it you can fix it.... Software can be bought or downloaded from virtually anywhere. Just find out what is being used in the industry around your target area and use that, I however would recommend Mach as a controller its easy and cheap. But just using this machine to teach basic CNC the budget should be way less than $7500. Now I realize that getting a budget for a build project may be a bit sticky in the school system but sell the point for the build, repair, and CNC education!!! The only reason I suggest Joe's 4x4 is that it is a sturdy well designed and fast build using tools you would have at the school in the Wood shop or simple maintenance shop. And it comes with a complete set of drawings. There are certainly many more options here for DIY builds but for your application the powers that be will be more impressed with the end results having students do the build.

And lastly if you do have problems here is the place for support!!! I havent seen so much enthusiasm and dedication to fixing someone elses problems on known machines either built or bought.

AND Joe may cut you a deal on the plans and a kit!!! (sorry for that Joe)

Bob

[Stepper Monkey]

I was just noticing in your post that you seem to have a basic misunderstanding of the underlying interaction between mill and software.
I guess the direct answer to your question "would the mill work with Mastercam?" would be a yes. More correctly, there is no direct link between mill and CAD/CAM software, there is an interstitial layer in between.
In short, CAD software solely models the image, CAM software is what converts it into a machining path (many packages can do both), the CNC software is what physically oversees and controls machine movement.

Here is an image that might help simply explain, shamelessly hotlinked from our friends at Flashcut because I'm feeling lazy today....



In reality, almost any mill will work with Mastercam, and vice versa, and by the same token just about any other CAD/CAM package, simply because the transition between steps 2 and 3 here involves a translation into a fairly universal command set called G-code.
Though many manufacturers try to bundle it all together in a package and lead people to think mills and software suites are exclusive or interlinked, the only real proprietary part of the whole mess >can< be the final CNC level interface, and even that is not a given as universal configurable programs like MACH3 can come into play there to replace them, or things called postprocessors to integrate with them.

In other words, you can get about any brand software you want to work with about any brand mill you want, and almost without exception do it quite easily.

As for machine suggestions, a Minitech is an awesome, accurate, and well-built device, and the cost reflects it. For production-level duty for high-tolerance parts there can certainly be a big advantage. It is a very professional machine.
For what you want to do you could just as easily go with a machine many times cheaper and not notice the difference. The earlier suggestion of a Taig is an excellent one. It is very robust and of very good quality, but is not as accurate, and that is a big part of where the extreme price difference comes in. It would not be a trade down for educational work in terms of reliability or capability or anything like that. It is very well-suited to task.
Also, as the Minitech is essentially a hand-built machine, and the Taig more or less mass-produced, the replacement parts are also very much cheaper and more readily available should students write bad code and mill bits of the machine off, and it will happen! So cost and ease of maintenance might also be a consideration toward a Taig. With the same budget as the Minitech/2 you could get about four or five Taigs, including a decent stock of accessories and spare parts for mishaps.
There is also another option. The costs are about the same as the Taig, and many companies catering to the educational market for CNC machines have tended to go with a company called Sherline for many of the same reasons stated above. Given my preference, I'd stick with the Taig, but both are very well suited for educational uses.

[cyclestart]

Originally Posted by carman Does anyone on this board have this same mill?

Few if any. Most of us expect more metal at that price. Cheapskates many of us. The components are less than exciting to read, acme screws, round rails , mystery electronics. Let's assume they are all very high quality. The machines have the no-nonsense look of serious machinery.
http://www.minitechcnc.com/machine_tscale.htm

If yes what software are you useing? Will it function with master cam?

Looks like they supply Mach3 (at an extra cost?) for the cnc bit. Stepper Monkey covered the rest extremely well.

[carman]

Thank you all for the advice. I went and looked at the website for the Taig. They are a lot cheaper price for sure. It would be nice to have several mills working at the same time.If I end up having to replace what I have then that could be an option. I have one of the older Mini mills’ that has been in the class room since 1992. I can not complain about the mill because it has worked well. The problem I have is that it needs to be updated to run on a Windows XP machine (not Dos or win 3.x). They said they would rebuild and update the machine for $1200. The students do not enjoy writing code but do enjoy making chips. That is why I was thinking that Mastercam Would let them carve their name and make an island fairly quickly. Once I have them hooked then I can teach them more about the nuts and bolts. I figured since the Local votech had Mastercam that I would try and mimic their program. From what it looks like (great example stepper monkey) that it should work.

Next question. Is there an easy to use and real cheap cad cam program that I can load on several computers for thestudents to use? Will LAzycam work like a cad cam program?

[sansbury]

CamBam will generate all your basic 2.5D G-code pretty well and the basic version is free and actively maintained. The developer is a member here--I think his name is 10Bulls. It is mainly a CAM program but it does have some *very* basic drafting functions as well as TrueType lettering so it might fit your bill well.

Mastercam is a very capable application and would no doubt be able to generate proper G-Code. But it's probably overkill by a factor of 10 at least. Sometimes very powerful applications have a very steep initial learning curve that can make them discouraging.

Working with G-Code I sometimes feel like I've come full-circle. We had Apple IIs in the classroom from when I was in first or second grade and they had us programming them in LOGO to move the "turtle" around and draw things on the screen. Makes me wonder sometimes why they waited another six years to start teaching algebra.

[cjdavis618]

Carman, My advice would be to contact Alibre for a demo. They have a free version of software and also a version of a cam package that integrates into it. It has a much smaller learning curve than most other packages and they are "School Friendly" It is limited in features, but the price is right.

Check out Alibre.com and I am sure you will find all the help you will need. You will still need a controller, but you can use the demo version of Mach 3 as well and contact them about licensing for Schools as well, they are a great company.

[sansbury]

Stay away from Alibre unless you're trying to teach 3D parametric modeling. If all you're trying to do is carve names and make a few 2.5D parts, then it's like using a dump truck to pick up a single sack of gravel. It's a great application but I am a software developer and I found it extremely complicated to get started with, as I'd expect it to be given what it is designed to be capable of.

[cjdavis618]

Well, I have to disagree. I am a Network Consultant with no background in CNC or cad and picked it right up. I looked at autocad and several others and found nothing but confusion. Alibre, I was able to get parts done and procedures down in a short time frame and at a great price. The tutorials that come with the program are a great way to start and you can work in 2d if you choose. Pick a plane and draw. That is why there are 2d tools and 3d tools on the menus.

It certainly won't hurt him to try it.

Edit... So far, all of the parts that chips came from were 2.5d parts. And your right, I might need a dump truck to move them.

[cjdavis618]

Carman, It appears that we really don't know what your goal is for the students. The machine you have mentioned may not be the better choice for your task. The taig mill is a very capable machine, as are the table type, cnc router plasma systems.

You mentioned carving a name and making an island (3d?).. What are your ultimate goals for the students? What are your thoughts for the class program and is this a program course or just a "teaser" course for the students to give them options for the following years? You mentioned having the old mill for use by the students. Are you looking for something bigger or similar to the same size with more capability?

Your options are limitless. Some school programs break the class into groups and have them make individual parts for assemblies. That is real teamwork and helps them understand the manufacturing process. In that regard, Alibre would shine. But in simple names and carvings, the program would be overkill.

You wouldn't be limited in features with Alibre if you were to expand the program though. It can certainly do simple as well. We just need to know more of your goals in this arena.

[sansbury]

Originally Posted by cjdavis618 Alibre, I was able to get parts done and procedures down in a short time frame and at a great price. The tutorials that come with the program are a great way to start and you can work in 2d if you choose. Pick a plane and draw. That is why there are 2d tools and 3d tools on the menus.

Well, I will have to take another look at it then. I ran through it about a year ago, and while I really liked the capabilities, it seemed like the workflow to just do a simple 2D projection was a bit much. Going from a simple idea (e.g. 4" square with 2" circular hole in center) to a DXF required a lot of "yak shaving" or at least that's how it appeared to me.

Generating the DXF in particular seemed to require a moderately long series of steps as the only way I found to do it was by creating a projection from a 3D model. This got annoying quickly as I often wanted to go back from the CAM to tweak a dimension in the original DXF.

I kept looking for a 2D-only mode and couldn't find it. I will say that the full 3D parametric modeling aspect seemed pretty well done. I haven't worked with SolidEdge or anything on that level so I can't compare it to much, but having worked with Autocad R/10 long ago, the whole idea of parametric modeling was a revelation, like going from arithmetic to algebra. It certainly wouldn't be a bad thing to introduce the students to if that was the idea.