Position of Z carriage on PRT Alpha w/router

[blackhawk]

I have a 9648 PRT alpha with a PC router. I am the second owner, so I inherited the position of the Z carriage. I am talking about the vertical position. There are 4 holes on each side of the steel frame. My Z carriage is mounted to the aluminum extrusion using the two uppermost holes. If I cut something much over 2 inches thick, I start getting close to the top limit of travel when you count in the cutter length. I would like to have a little more height.

I just wanted to hear if other people use the center 2 holes instead to raise up the carriage about another 2 inches. The only drawback that I see to this is that the Z carriage will be extended out another 2 inches when you are cutting at the table surface. Has anyone seen that extra 2 inches of extension cause deflection while cutting?

[blackhawk]

I know there are people out there running a PRT with a PC router. I just wanted to hear where the majority of people mount the Z axis. Pros and Cons of raising it up to the next set of holes?

[scottcox]

Brad,

I move my spindle up and down the plate as required for different types of jobs (and different bit lengths).

Your cutting strategy will determine the deflection in either position, but I've never experienced negative results from the extended position.

[blackhawk]

Scott - So you unbolt the entire Z assembly from the Y carriage extrusions from job to job? Isn't that a hassle to dial in the vertical alignment every time you move it?

[scottcox]

No, I just move the spindle up the mounting plate, so the Z axis alignment doesn't change, just the height.

I also have a PRT Alpha, btw.