View Full Version : Newbie Another new to CNC


Garage Dog 65
09-11-2008, 10:20 PM
Hi all !

I'm new to the cnc world and looking for some guidance. I'm planning to startup a cnc business here at home and looking for some help on equipment and software choices.

Plans are to start with Solidworks as the design tool and MasterCam as the CAM tool. For the equipment I'm looking at the Roland mxd-540 with reverse engineering capability for prototype/modeling and small runs - with the Tormach pcnc 1100 for production. Once business supports a larger machine - I'd move into a Haas VF3 and a separate building on my property.

I live on the west side of Indianapolis In - which has a huge amount of motorsports activity that's growing every month. I beleive there is an opportunity to provide low cost/low volume parts prototyping and limited production to those race shops and street/hot rod shops in my area. I have checked with local machine shops on my own car project needs and they are interested in large runs and/or large accounts and shun prototyping work volumes.

Couple questions for you to ponder:

1. Is MasterCam the best choice for a small shop as described above ?

2. Is there a machine like the pcn 1100 that has the reverse engineering function that would allow me to skip the desktop Roland and instead invest those dollars in the large machine and support tooling ?

3. If no to question #2 - is there a better decktop unit with the reverse engineering capability ?

I have been reading your forums for the past week now and the amount of info and guidance here is quite staggering and very usefull. Thanks to all for your input and any additional guidance, comments or concerns would be greatly appreciated.

Jim

Stepper Monkey
09-12-2008, 12:05 AM
I've seen some of the purpose-built and ungodly complex and expensive (six figure +) reverse engineering setups with a crapload of axes, but they are a somewhat different animal from what is done on the Roland and other CNC RE packages. They basically are just the addition of a 3D scanner that fits into a collet, and scanner software to the base mill package. You can just buy those separately from a number of companies and use them with any mill just as well.

Someone who has actually used this specific Roland system in practice (I have only had the Roland setup demoed to me by a rep and didn't purchase - I wasn't impressed) might know differently, but it appeared to be nothing more than a standard 3D scanner and software plugged into the mill. The only thing it did that I haven't seen with other setups was that it had macros that pretty smoothly automated a couple of the basic data manipulation and export format steps to make it more convenient (i.e. idiot proof) to use. Macros aren't even always a good thing, depending on whether you want to do with the data exactly what the macro wants to do with it...

I would suggest that you are correct in thinking the best option is just getting a probe or laser scanner assembly and some good scanning/RE software to chuck into the Tormach or whatever system you eventually get. It will do all the same things, if maybe with an extra step or two of file handling or format conversion depending on how slick the software you are using is. The scanning capability is the same thing exactly though.
I don't see what an extra CNC mill dedicated just to having the probe chucked into it permanently would accomplish for you, and an expensive one to boot in this case. Especially since it is too small to do anything useful for your needs other than scan.

Just as another note entirely, the 3D scanning setup I did purchase from another company, I sold after a couple of years finding it was so seldom used as to just be taking up space. Not that it was a bad product, it did EXACTLY what I bought it for, its just that I found much faster and better ways to RE items without scanning them. Unfortunately, scanning gives you a great set of incoherent data, so you can duplicate directly (even then not always!), but it is impossible to alter that data easily. Especially if what you are trying to repro is a worn or damaged part. Even just smoothing off casting flash, pits, or stamped/raised characters is a serious pain. Machining models of cast parts sucked as it wanted to duplicate the casting grain structure.
It was just far easier to sit down with a mic and coherently model the part from scratch, or even just to scan the item in a flatbed scanner and use it as a template to overlay actual vectors. I was doing similar jobs as you want to with gun, auto, camera, motorcycle, and jewelry parts and I found almost no jobs where it actually saved time, lets put it that way.
Your mileage may of course vary, but I wouldn't get locked into any five figure system purchase until you've tried it out and know it will work well in practice for what you use it for!

jalessi
09-12-2008, 12:13 AM
Jim,

Welcome to the Zone.

The Roland 540 is fine for really small parts like jewelry however not for prototype race car parts.

For reverse engineering there is no problem attaching a digitizer probe to 99.999 % of any CNC machine that runs Mach3 including the Tormach.

Mach3 has a Digitizing/Probing Plugin.

http://www.machsupport.com/plugins.php

Then all you need is a digitizing probe and point cloud software to go along with the cad program of your choice.

Jeff...

Triv
09-12-2008, 11:14 PM
Mastercam is probably the widest marketed and sold cam package. That means it may be easier to hire someone skilled with them.

Also, try to not infringe on somone's patent rights when reverse engineering. It may get messy in the courts.

Triv

sansbury
09-14-2008, 01:43 PM
Forgive me if I'm being presumptuous but I have more questions about your business plan than the machinery side of this. My perspective here is as a business owner (different industry) who has learned some hard lessons along the way :)

The number one problem in any business isn't supply, but demand--sales, not manufacturing. You've found out that no local shops want prototype jobs. Why? Perhaps they're set up for production runs because that's all buyers there want. Or maybe it's because no one is willing to pay what it costs to make small volumes.

I'd do another round of interviews but from the other end--go talk to race teams, garages, the places who might buy from you, and ask them where to get stuff made. One thing you may find is that there are other guys in their backyards cranking out parts who simply don't advertise. Second I'd ask them about how much work like this they actually might have to give you. Take whatever they say and cut it in half. Multiply by the number of places like them you can find in the yellow pages. This gives you some sense of what the potential market is really like.

The thing that kills small-run/prototype shops is the cost of sales, which can be very high relative to the cost of the first job it brings you. Prototype shops tend to be established and heavily supported by word-of-mouth and longstanding relationships. If you're going to break through those you will need to offer something special.

The flip side is that small independent operators can work with very low overhead, no OSHA, insurance, overtime, etc. Some guys are genuinely happier making $15/hour working for themselves than $20/hr for someone else. Nothing wrong with that but worth keeping in mind the economics of why it works and whether that's really what you want.

Last, I wonder a little given your "new to CNC" statement and talking about getting a whole pile of expensive software and machinery. Are you a machinist just moving to CNC or a hobbyist who thinks this would be a fun way to make money? I've spent most of my career building software companies and I know how they work, where the costs and leverage come from, etc. By comparison I know almost nothing about machining. I know a little of the trade skills and some of the business dynamics from talking to friends who own shops.

If I was going to do this as a business, my first move would be to get a job with an established shop and learn more from the inside. If you have some capital to work with, one angle might be to try and partner up with an established smaller shop, maybe one with an older owner (not uncommon here in New England) who might want to retire and sell. Buying machinery is the easy part. Any idiot with cash or a credit line can do that and many do. Being able to crank out real work and selling that capability is the hard part.

awerby
09-14-2008, 07:52 PM
Jim,

Welcome to the Zone.

The Roland 540 is fine for really small parts like jewelry however not for prototype race car parts.

[The MDX-540 has travels of more than 15" x 15" x 6"; that's a bit large for jewelry, although it could be used for that. It's a fairly massive machine that can cut plastics and non-ferrous metals, although it's not recommended for steel. Depending on what race-car parts you're talking about, it could work well for them.]

For reverse engineering there is no problem attaching a digitizer probe to 99.999 % of any CNC machine that runs Mach3 including the Tormach.

Mach3 has a Digitizing/Probing Plugin.

http://www.machsupport.com/plugins.php

Then all you need is a digitizing probe and point cloud software to go along with the cad program of your choice.

Jeff...

[Roland's piezo-electric digitizing probe works better than the typical deflection switch probe, being both physically finer and more sensitive, and the software to produce mesh files from the scans is included with it. They also include CAM software which, while it doesn't have all the features of MasterCAM, isn't nearly as difficult to master. For someone without a lot of machining background, it's a pretty good way to get started with all this. But you've gotten some good business advice here; making stuff isn't the hard part - making money for making stuff is what's hard...]

Andrew Werby
www.computersculpture.com

Garage Dog 65
09-20-2008, 10:54 PM
THANKS to everyone for the info, comments and concerns !!! All very good comments and valuable advice for sure.

I do not have machining in my background. I'm a 35 year airline mechanic and electronics/electrical specialist who for the past 15 years have (had) been the business manager of the training department with a 5 million budget - recently displaced when the airline closed..... Aviation is an unbelievable mess now with everything being sub-contracted out - almost to the point where the airlines are just ticket agents.

At 47 - I think it's time for a career change and to start my own business and do the stuff that I am most passionate about. Living here in Brownsburg and near Indy, I'm in the center of some pretty serious racing operations - So that's what led me to a business plan of a home cnc for this local industry and producing parts for the cars I build. I also have a bunch of car builder friends that need/want one off custom parts for their projects like what I build - but don't want to wait weeks for their stuff and/or are scared to approach a machine shop with a thumbnail sketch for their part and feel stupid.

I have always been involved with racing, auto restoration and fabrication (currently working at a restoration and hot rod shop) - with a little manual machine operation along the way to manufacture parts for my own usage, (mills, lathe etc) - I'm a certified welder and also have 3 years of composites training. (My current project is a 65 Porsche 356 coupe - that I split down the middle and added 9 inches in width - built a custom dual tube frame and added a 2002 C5 corvette drivetrain (with 6 spd mnl transaxle) and the complete C5 vette suspension). Plus all the chassis jigs, jig table, tube bending - etc.

I have been here for the past 30 days on this great site reading just about every post on the topic and consuming as much info as possible - and have decided on just the Tormach machine with the deluxe tooling/equipment package, Solidworks and SprutCam - with their digital probe for RE if needed. I will go through and do a complete interview of the shops in the area as recommend by Sansbury (great post sir !!) before I start to spend a ton of money. (my wife is also a CPA, director of a finance department of an international company and a business unit manager too - and has to 'approve' all my purchases :)

As a displaced aviation employee - the state of Indiana has also provided a grant to our company employees for transitional education and degrees. So I plan to use my grant for a machining technology degree - while working part time in a local shop getting hands on experience.

Hope I didn't bore everyone with all my background - just wanted to give you some detailed info on me so that you would be able to provided additional comments if you'd like.

Thanks again for all the help and encouragement !!!

Jim