Upgrades

[f0bic]

is it possible to upgrade a pr96 to a pretty decent machine with the PRT 4g upgrade?

[bleeth]

I believe that Dirk H did a similar upgrade with his gecko board on a PR. You will jog faster and get a better cut resolution due to the improved stepping numbers and upgraded SB software, but your cutting speed will still be limited by the stiffness, or lack of it, of the gantry and rails.

[f0bic]

so speed will be the major loss between this idea and a newer bot...? I'm sure the new bot will be better all the way around, but I hope for the best quality not speed...

[bleeth]

Best quality will come from a newer rig than a PR.
If I were looking to spend as little as possible with best quality I would get either a new PRS standard or a PRT equipped with the 4g and running the latest SB software. More specifics can be determined by what you are planning on primarily cutting and what your real budget is. The gearing in the PRT motors results in smoother cuts with gecko boards than the 1:1 older Alphas. If I had an Alpha I would take advantage of SB's current upgrade offer for the new motors. If you are involved in intensive 3-d work you will always be speed limited by the short distances traveled in each code line, but the quality will be much improved by a combination of microstepping, operational software, gantry stiffness, and router/spindle trueness. With the upgrades available now the biggest limitation becomes the configuration of the structure and how much it will take without flexing. Any of the older style gantries and cars, when welded, immediately increase performance and accuracy of cuts. My nearly 4 year old PRT with a spindle and gecko board cuts cab parts with zero finishing required on edges and perfect part squareness.

[f0bic]

I would really like to have the PRS standard and the price is not the problem... the problem is the wait....I can get my hands on a older pr96 now....does anyone know the wait on the 4g upgrade??

[bleeth]

An old saying goes move in haste and repent in leisure. If it takes six weeks to get a PRS you are only 6 weeks older-not much in the overall scheme of things. I would wait for delivery of a new machine if I were you. You will be able to fill the time learning software. When I bought mine I bought Artcam Pro with it and got delivery of that quickly. Whatever cad-cam software you get it will take time to learn how to use it effectively. Learning software and putting together your new machine and learning operational methods all at once doesn't happen anyway. Call Shopbot Monday for answers to delivery schedules.

[gene]

Dave
What type cf cutters and what materials are you making cabinets from ? What is the design software are you using? Have you upgraded the motors to the 7.21 - 1 motors . Is there a site we can see your work ? Thanks

[bleeth]

Gene: I'm using a 5mm bit from Centurion for all my box side machining and cutting. I cut in two passes. I use melamine, plywood, and mdf cores depending on the specs of the project. I have original PRT geared motors. Site under development but here is a pic of a playroom in a children's hospital we did:


25486.jpg

The equipment vents were a couple of minutes on the bot too.

[gene]

Dave,
The playroom looks great . Do you have a link for centurion tooling? I have an alpha 48x96 and i am trying to get a better quality edge that i dont have alot of sanding or prep for edgebanding after the parts are cut . Could you recommend a tool # and speeds that you are comfortable with. Are you cutting 3/4 materials? Thanks for your help.

[bleeth]

Thanks Gene: I'm not the only botter using Centurian by far. There is much about them in the suppliers section of the forum. Here is their link:
http://www.centuriontools.com/
Yes I'm cutting 3/4. I have a PRT and if I cut over 1.8 ips with that bit it gets a little rough. I run the spindle at 18k. Takes about 1/2 an hour to completely machine 9 upper sides out of a sheet with all shelf holes, hinge plate holes, and dados. Less for base sides.