ShopBot PRS alpha Converted to Acorn

Post your completed retrofits for the world to see.

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Gary Campbell
Posts: 2164
Joined: Sat Nov 18, 2017 2:32 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: Acorn 238
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Marquette, MI
Contact:

ShopBot PRS alpha Converted to Acorn

Post by Gary Campbell »

Circa 2007 PRSa, commercial machine with Acorn Closed Loop retrofit

GCnC Control
CNC Control & Retrofits
https://www.youtube.com/user/Islaww1/videos
cnckeith
Posts: 7166
Joined: Wed Mar 03, 2010 4:23 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: Yes
Oak CNC controller: Yes
CNC Control System Serial Number: none
DC3IOB: Yes
CNC11: Yes
CPU10 or CPU7: Yes
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Re: ShopBot PRS alpha Converted to Acorn

Post by cnckeith »

Need support? READ THIS POST first. http://centroidcncforum.com/viewtopic.php?f=60&t=1043
All Acorn Documentation is located here: viewtopic.php?f=60&t=3397
Answers to common questions: viewforum.php?f=63
and here viewforum.php?f=61
Gear we use but don't sell. https://www.centroidcnc.com/centroid_di ... _gear.html
Gary Campbell
Posts: 2164
Joined: Sat Nov 18, 2017 2:32 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: Acorn 238
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Marquette, MI
Contact:

Re: ShopBot PRS alpha Converted to Acorn

Post by Gary Campbell »

Scott has had some time to do a little tuning. Kicking up the rapids and playing with the acceleration and smoothing. A tweak here and another there. Looks pretty good for a "kid" with only a few weeks on a new system:

GCnC Control
CNC Control & Retrofits
https://www.youtube.com/user/Islaww1/videos
Gary Campbell
Posts: 2164
Joined: Sat Nov 18, 2017 2:32 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: Acorn 238
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Marquette, MI
Contact:

Re: ShopBot PRS alpha Converted to Acorn

Post by Gary Campbell »

By email request, which was to show both videos, side by side so that the user can see the difference.

Same machine, material, same bit, same feeds, same rapids. What's different? Double the resolution, increased acceleration. How the controller handles curved vectors, how the controller accelerates the tool. Watch for the almost unnoticeable slowdowns on the SB controller as it struggles to spoolup data for circular cutting action. Of course this file is full of circular cutting action.

Another item you may notice is that when cutting in 2D offset mode (G52), the SB controller must return to the X0, Y0 position to apply the positional offset.

GCnC Control
CNC Control & Retrofits
https://www.youtube.com/user/Islaww1/videos
Gary Campbell
Posts: 2164
Joined: Sat Nov 18, 2017 2:32 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: Acorn 238
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Marquette, MI
Contact:

Re: ShopBot PRS alpha Converted to Acorn

Post by Gary Campbell »

This video, another with side by side action, shows identical files at identical speeds. You can easily see the difficulty that the ShopBot has maintaining feedrate when cutting circular vectors. The additional code required to transmit that many small segments to execute an arc, will always slow the tool down.

Note that even with a minor half second head start, it doesn't take too many curves for the Centroid Acorn controller to pull ahead.

GCnC Control
CNC Control & Retrofits
https://www.youtube.com/user/Islaww1/videos
Sword
Posts: 652
Joined: Fri Nov 30, 2018 1:04 pm
Acorn CNC Controller: Yes
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Hickory CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Thorp WI

Re: ShopBot PRS alpha Converted to Acorn

Post by Sword »

That machine looks awfully familiar, as well does the wall of misfits! :lol:

I guess it's about time I jump in here and say a "BIG THANK YOU" to Gary for mashing up these videos and for putting together a top notch control box! They're truly a work of art and a pleasure to work with when installing and getting everything hooked up and running! Another "BIG THANK YOU" to the Centroid team for putting out a quality hardware and software solution that just WORKS! It's so nice to have a solution that is current, maintained and updated, and doesn't crash or lose connection on a regular basis. I decided to give the NEMA23 motors and 5:1 gearboxes a try and so far, I'd say that they seem to perform very well. My rapid rates are the same as before, but with much better acceleration. I haven't had the jobs to really push them yet, but I would say that they easily perform over and above the old NEMA34 motors. That turkey call job and it's three separate operations ran non-stop for about 10 hours without a hitch (well, one, but it didn't count ;). Resolution and edge quality on the final pass, a 7 degree dovetail bit around the perimeter, looked really good. The master file calling up and offsetting the related files was a breeze to put together and repeat over and over and as you can see, the motion control handles it all with aplomb!

I have several 3D jobs coming up along with other stuff, so we'll get some good quality time to tune and tweak. ;) Here's a little v-carve action on a customers part. A little tweaking to the smoothing params and v-carving runs great. https://drive.google.com/open?id=1yqJx9 ... bPkfhdJ64s

I still have a few things to do with the conversion, hook up my cross hair laser locator, the fixed tool touch off, and various user macros, but all in all, it's been a breath of fresh air and a blast getting it going. Oh, and that MPG thingy, that's worth the price of admission right there I tell ya! If you don't have one, you need one! 8-)

Thanks again Gary and Centroid, CNC life is good again!
Scott
Scott
Gary Campbell
Posts: 2164
Joined: Sat Nov 18, 2017 2:32 pm
Acorn CNC Controller: Yes
Allin1DC CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: Acorn 238
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Marquette, MI
Contact:

Re: ShopBot PRS alpha Converted to Acorn

Post by Gary Campbell »

Scott...
Now that you have had around 6 months of daily use with the Centroid control, how about a bit of a review comparing the two controllers.
GCnC Control
CNC Control & Retrofits
https://www.youtube.com/user/Islaww1/videos
Sword
Posts: 652
Joined: Fri Nov 30, 2018 1:04 pm
Acorn CNC Controller: Yes
Plasma CNC Controller: No
AcornSix CNC Controller: No
Allin1DC CNC Controller: No
Hickory CNC Controller: No
Oak CNC controller: No
CNC Control System Serial Number: none
DC3IOB: No
CNC12: Yes
CNC11: No
CPU10 or CPU7: No
Location: Thorp WI

Re: ShopBot PRS alpha Converted to Acorn

Post by Sword »

Two controllers? Oh, that one, I almost forgot completely about it! ;)

Well, while going 6 months without a comm error would be enough, we also have better resolution, equal or more torque, improved motion control out of the box with much better\easier motion modifier options by way of smoothing presets for various cutting situations, better feedrate and RPM control, etc. etc. Because of all these, substantial time savings for production runs and 3D relief cutting has been proven as well. The full featured G-code set opens up a plethora of optional programing with less effort (and a lot less commas). Last, but certainly not least, a greatly improved user interface experiance (with the exception of that drippy faucet ;) :lol: ) that is actively maintained and improved upon.

All in all, it has been a smooth seamless painless transition and any ShopBotter contemplating an upgrade to their aging controller/software and it's inherent issues should take a serious look at the options available to them with a Centroid/Acorn system upgrade!
Scott
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