To CNC? Or not to CNC?

[sanddrag]

Well, to have a cnc you would need many thousands of dollars. The absolute cheapest one I have found is this http://www.maxnc.com/page3.html and it is extremely small. You couldn't make very big stuff with it. Plus, there is no automatic tool change or coolant or anything like that. You'd be better off getting yourself a nice set of manual machining tools.

The advantages of CNC are:

Very precise and accurate
Quick
Numerous parts of the same are easy
Can make very complex shapes and large cutouts and bores

Disadvantages of CNC:

Cost
Programming time/expertise needed

For your machining needs, see if there is a college nearby that is willing to help you out. That's what we did and they give us full support of a half dozen manual mills and lathes, 3 CNC mills (one of them is 710 ipm 30 hp vector drive) and a CNC lathe plus several other tools. We only have to pay the class fee of $24 dollars per student per semester.

CNC mills can be made from manual mills but the cost vs. benefit may not be worth it. Here are a couple links of people who have done it.

http://www.bmumford.com/cncmill/
http://www.embeddedtronics.com/metalworking.html

[kacz100]

Well a CNC can be a huge money spender but I used to be on team 40 and we had a great sponsor Intelitek, they make some great machines that are tabletop and are just as good as the other larger counterparts. Well enough of me jabbering; here is the link for all you CNC mill and lathe people

Intelitek website

[indieFan]

Here are just a few comments:

As someone who has a CNC to work with in "my" college lab, I can tell you right now that if you don't have anyone who is experienced in running one, you will find yourself extremely frustrated during the season trying to make parts. I have been coding everything directly into the CNC using straight G-codes and have now broken a number of tools due to incorrect speeds, incorrect feeds, or my personal favorite, incorrect Z-heights. Please do not make the mistake of thinking you will be able to learn to run a CNC quickly the way I thought I would. I read all of the manuals cover to cover before I took a one week training course at the company, and I still had no clue what I was doing while I was there.

There are also people that say there are programs out there to make life easier, such as MasterCAM, but they are only giving you a small part of the story. You still need to understand how that software gets integrated with the hardware of the CNC, esp. when it comes to the Z-axis. Until you gain that understanding, the software is worthless. (Yes, I still have to learn how MasterCAM and/or EdgeCAM is integrated with my lab's CNC.)

Other people have commented in part on the cost of the CNC so I'll only add that the tooling that was set up for the one in my lab cost $15,000 for just toolholders and what were considered the standard tools that we would be using. I do not know what the tooling costs would be like for a smaller CNC.

indieFan

[Jon K.]

This year RAGE was lucky enough to have CNC Software, Inc. The creators of MasterCAM as one of our sponsors. I am lucky enough to be able to use the machine donated to our team and the use of MasterCAM software. It does take a while to learn the basics of the machine, but we have two people working it and between the two of us we know most of what needs to be known. We also have the President of MasterCAM teaching us how to use the software and the CNC machine. We are very lucky this year and are hoping to be able to create aluminum sprockets to sell to FIRST teams in the near future. But we are also helping out a few teams this year by creating sprockets for them as well as our own. I have found the CNC machine to be very easy to use when you get used to it, but like I said we have someone with a large knowledge base in the field to help us.