[Ray C]

Hello...

My name is Ray and I have an EE/CS/Math background but, my passion has always been machine shop work. I have a full manual machine shop with all modern manufacture, light industrial sized equipment and am also setup for heat treating as well as precision tool and surface grinding. I just purchased a full 4 axis CNC machine and after it's setup, plan to teach myself how to use it. It's probably worth mentioning that I have a reasonble background with Alibre Professional CAD. They recently released a new version and I'm about to upgrade to that (fortuantely, I pay the annual maintenance contract)... I gather Alibre's CAM partner is MecSoft. Anyhow, I hope to meet new folks and learn more things here. In the beginning, it's not likely I'll be able to contribute much so I'll do my best to read as much as possible before killing bandwith with newby questions.


Ray

[awerby]

Hi Ray. It sounds like you've got the optimal background for someone getting into CNC - I wish I knew all that stuff when I got started! Alibre, as you may have heard, was recently bought by 3D Systems, but not much has changed besides the name - the pro version is now called Geomagic Design. If you want to get the Mecsoft CAM program that plugs into it, please let me know - I offer a significant discount. What kind of CNC machine did you just get?

Andrew Werby
www.computersculpture.com

[Ray C]

Hi Andrew...

Yes, after many years of operating manual mills and lathes, it will be nice to learn CNC. I do some work for local shops; mostly one-off fabrications or repairs on existing parts. Recently though, I've had requests for small quantities and CNC is probably more appropriate -even though the parts are not very complex.

As for Alibre, I've been using it for a couple years and it serves my purposes well. I haven't yet decided on a CAM program. There are many out there and I'll read a lot here to gain insight. At the onset, I'll probably just write some simple G-code. I'm not familiar with it but, have programmed various forms of assembly languages which have a roughly similar structure like many other procedural languages.

All of my major equipment for the past 5-7 years is from Precision Matthews (aka. Quality Machine Tools Home) and the CNC mill is this one: PM-45M-CNC which is a Rong-Fu clone that's been fully CNC converted. I've ordered the "full-blown" model as I've learned over time that incremental upgrades are very time consuming and often more costly to add later on. This unit natively comes with an R8 spindle but, I believe a NMTB-type is more appropriate. Would you recommend a #30 or 40 spindle? I gather these are the more common size for machines like this. The spindle is easily changed in this unit and can upgraded in about an hour to NMTB at a very low cost.

Ray

Hi Ray. It sounds like you've got the optimal background for someone getting into CNC - I wish I knew all that stuff when I got started! Alibre, as you may have heard, was recently bought by 3D Systems, but not much has changed besides the name - the pro version is now called Geomagic Design. If you want to get the Mecsoft CAM program that plugs into it, please let me know - I offer a significant discount. What kind of CNC machine did you just get?

Andrew Werby
ComputerSculpture.com ? Home Page for Discount Hardware & Software

[awerby]

If your parts are really simple, I suppose you can code them by hand. It's good to learn G-code, and you can follow the evolutionary progression of machine tools through the 20th century that way. But if you've got a CAD program and can use it effectively, you can unlock its potential by getting a CAM program that automates the rather tedious steps required to make even fairly simple parts. It's great to be able to design something in CAD and then watch the machine carve it out automagically. If you decide to make more complex parts, it will really save you a lot of time, and make things practical that wouldn't be otherwise. Granted, CAM-written programs tend to be a bit less efficient in terms of lines of code and machine movements, but since you're not cranking the handles, that doesn't really make much difference.

The machine you've chosen seems pretty good, and if you've got an ongoing relationship with the vendor, they'll be more likely to be forthcoming with tech support and customer service. But I wonder if you won't end up wishing you'd got something with an automatic tool-changer. The choice of a spindle configuration really boils down to the power of your spindle motor. If the motor can handle larger-diameter tools, then go with the larger (NMTB-40) system. A "fast" taper like that makes it easier to change than the R8 style, since you don't have to bang on it to get it to let go. It's probably going to be cheaper to get a collet chuck for it than to outfit yourself with a whole set of tool-holders, but you might find a great deal someplace.

Andrew Werby
www.computersculpture.com