Big is better?


Recommended Posts

Already there are two threads posted about building what look to me to be really big CNC platforms.  I get that a bigger table provides more work area, but is ther something more to the size of these units?

And what's with the smaller units  one sees in the stores?

Link to post
Share on other sites

It's mostly about available space. The cost difference between a 2 x 4 and a 4 x 4 is minimal, since it's mainly just more steel or aluminum once you have paid for the spindle and drives and controller. For hobbyist applications you may never need more than a 2 x 3 or 2 x 4 work area. But the larger the table, the larger the possible projects. That said, most software allows for jobs to be tiled - breaking the job down into whatever capacity you have. 

Kind of like jointers, I guess. Buy a 6" and you'll long for an 8". Get an 8" and you'll want a 12".... 

The router that Carl and I are getting up and running is larger than most hobbyists would need or could justify. But Carl also has a complete Felder shop, so there you go.

 

  • Like 2
Link to post
Share on other sites

I don't really think of my machine as being that big.  The cutting area on my machine is approximately 27.5x20.5x8, with a footprint of 32x39.5  I would consider it more mid-range.

There were three factors in determining size for my build.  1) Room in my shop.  2) The size of the work pieces I will be putting on the machine.  3) Finally, the cost. 

That said, size doesn't necessarily make the machine better, it really comes down to what you use it for.  I know someone building a machine that he is going to be cutting brass parts.  He needed rigidity more than anything.  This machine has a very small working area, but it is super rigid being made from aluminum plate.  

  • Thanks 1
Link to post
Share on other sites
15 hours ago, Mick S said:

The cost difference between a 2 x 4 and a 4 x 4 is minimal, since it's mainly just more steel or aluminum once you have paid for the spindle and drives and controller.

Well i think that's the main difference, as the area grows, you need to add stronger steppers, more rigidity, longer leadscrews and stronger rails. Rails and leadscrews aren't that cheap either, longer axis means more $ for them, and in smaller machines you can work with an Arduino+shield+nema17 so you end up saving a lot on stepper drivers and motors.

In my case, I just bought most of the parts as I calculated I would need. The largest cutting area I can get is 2' x 3', keeping a reasonable speed and torque, while using nema17. Absolutely right on the available space though, we just need to maximize whatever components we can get our hands on through the design of the machine.

Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.