I'm trying to figure out the optimal distance between the bottom of my Y- axis cross member and the top of the table. Of cource the design of the Z-axis will play some part in the design. Is there a rule of thumb to follow or similar?
thanks
I'm trying to figure out the optimal distance between the bottom of my Y- axis cross member and the top of the table. Of cource the design of the Z-axis will play some part in the design. Is there a rule of thumb to follow or similar?
thanks
I make mine high enough to clear the thickest part you'll have mounted. Imo, for a router cutting wood, that's probably about 3". But I'm making it ~5" to allow for jigs or fixtures. The lower it is, the more rigid the machine will be.
Once I pick the gantry clearance, I then determine Z axis travel. I want to be able to reach the table with a bit sticking 1" out of the collet, and clear the gantry with a bit sticking out about 3". For 5" clearance, that's 4" down, and 3" up, for a Z travel of about 7". Then add 1 more inch or so for rapid clearance.
Gerry
UCCNC 2017 Screenset
http://www.thecncwoodworker.com/2017.html
Mach3 2010 Screenset
http://www.thecncwoodworker.com/2010.html
JointCAM - CNC Dovetails & Box Joints
http://www.g-forcecnc.com/jointcam.html
(Note: The opinions expressed in this post are my own and are not necessarily those of CNCzone and its management)
Thanks Gerry, I was looking at 4" or 5.5". I didn't figure in the height of the benchdogs.
For the most part, the greater the distance between the table and gantry, the greater the chance of frame flexing.
John
I'm about to take my Aluminum to the machine shop to have the gantry sides made (holes drilled). I was hoping the elite here would give me some comments.
I will be using 2 x THK25A bearing blocks per side. The HSR25 rail will be mounted to the lower slot of a piece of 80/20-3030. I have made sure all measurements comply with the measurements on the FLA machines as I want to use their bearing blocks with my design. The Y-Axis will be a piece of 80/20-3060.
The distance from the top of the 3030 to the botom of the 3060 will be 6.75" and with a 1.5" spoil board on the 3030 the clearance will be 5.25". The Aluminum is .75" thick by 8" wide and 18.5" long. I'm drilling .3281dia clearance holes for the 5/16 bolts, is this the correct diameter?
The THK25A blocks call for an 8mm bolt so I made the clearance holes .3125dia.
Thanks everyone