View Full Version : Question for Brady and other G4 upgrade and PRS Owners

11-10-2007, 11:11 PM
Ok So I have a 60X120 PRT standard with Milwaukee Router. I was considering upgrading to the 48X96 PRS Standard with 4hp HSD Spindle. What would I gain over adding the G4 controller welding and bracing my Gantry and adding a spindle to my existing set up? The Money seems pretty similar to do, little cheaper to upgrade maybe 1K less and minus shipping.

Brady Watson
11-11-2007, 02:13 PM
My original 5X16' PRT has been upgraded to PRS Alpha specs. I have the original non-modified table and a PRT Alpha style gantry. Aside from the new PRS table and gantry being a bit stiffer than my PRT one, performance is the same.

A 4G upgrade on your tool would be a no-brainer. Gussets and stiffeners are a good idea, but you don't have to go crazy with this. Your tool will be like a completely different CNC, cutting smoothly and quickly. You'll pickup 2.5X more resolution from the motors and about 1.5 to 2X more cutting speed. Your jog speeds will be in the 10-14 IPS range.

If your worry is that you will waste money on the upgrade, rest assured...Even if you want more performance out of the tool (say you decide to get a new PRS Alpha in a year) - the perceived value of your PRT went up more than the cost of the upgrade...So your tool would be worth more if you were to sell it. I cannot think of one negative thing about the 4G upgrade and think it is an absolute steal for $800 or whatever it is now.


11-11-2007, 04:33 PM
Does this 4G upgrade affect 3D carving quality? In other words, is it a big noticeable difference in speed. Our setup is the prt alpha 48 with Mwk router. I still want to keep this machine even though we are wanting a larger one.

Brady Watson
11-11-2007, 05:24 PM
The 4G (or 4th Generation PRT) controller is for non-Alpha machines only. Your direct drive Alpha is good, but for $750 (or whatever the going rate is now) you can upgrade your X & Y axes to PRS Alpha specs with 7.2:1 gearbox motors. These will effectively give you 2X the torque and about 2.5X the move resolution that you have now. The Z axis stays the same, although you can optionally purchase a 7.2:1 motor for your Z axis as well. This would essentially give you a PRSAlpha drive system on your PRTAlpha. This is the exact setup that I run. Resolution and performance are much better in my opinion than the 1:1 setup...plus in all of the cutting I have done, I have never been able to knock the 7.2:1 Alphas into 'Alpha mode' - meaning that they are much more powerful than the 1:1 motors you run now.