PRS and PRT

[kevinkev4]

What is the difference between the PRT Alpha And the PRS Alpha?

Kevin

[Brady Watson]

Depending on the year of the PRT, here are major differences:

PRS has:
AL extruded table
AL extruded gantry
7.2:1 geared motors
Hardened rails

PRT:
Steel table & gantry (later models had AL extruded table & gantry)
1:1 direct drive motors
non-hardened rails

-B

[kevinkev4]

Thanks Brady,
This one bought in 2006 PRT Alpha http://www.talkshopbot.com/forum/messages/11097/30707.html?1210786320 looks to be a good deal compared to a new PRS Alpha. Would it run ass fast and do as good of a job? Or would the difference in cost be worth paying for a new one?

[Brady Watson]

Kevin,
That is a nice machine. Be aware that while it has positional feedback (via Alpha electronics) that it is direct drive. The PRS Alpha has 7.2:1 ratio gearboxes which give much improved edge quality on plastics and very dense materials. I'm pretty sure ShopBot still offers an upgrade kit that replaces the X&Y 1:1 drive motors with the PRS 7.2:1 motors for a reasonable cost. You'll have to call for details on the price & availability. That may be a factor in deciding if a new tool or this one is right for you. In all, it looks like a nice machine.

-B

[scott_smith]

You’ll also want to add $600 or so (I didn’t check the current pricing) for CAM software. I’d throw out the part wizard and go with V-Carve Pro.
Scott

[erik_f]

Long term I think going with the PRS is the smarter choice...even if you had to go with a standard. Resale is going to be a lot better on the PRS and you should have less problems with the PRS because it is made better. I have owned a PRT and just got my PRS BT48...while in the world of CNC Shopbot is a Tonka toy...to me, the PRS embodies more of the same ideas used in the larger CNC machines than does the PRT. But the used machine is alot of machine for the money. I personally would go with the PRS even if I had to get a slower machine, but I'm coming from and old PRT with 300 ipm job speeds...so having 600 ipm jogs with the PRS standard is huge for me.

Erik

[kevinkev4]

Thanks for the info. guys. Very helpful.

Kevin