Upgrading the PRT-Continued from 2007 Archive!!!

[bleeth]

Wow-I had no idea that's how long it's been since I last did anything to "old faithful" but so much has changed conceptually since then that entire plans and concepts have been reworked. In the interim, after Dirks "Bot Rod" controller and the hardened Y rails were installed she's just been humming away with a couple of idiosyncrocies that we got used to and compensated for.
But now the parts are rolling in and the rebuild is in progress. Possibly disappointing to some I decided finally to adhere to a modified version of the PRS design built on my PRT steel frame. So therefore the original angled steel x rails are going away and being replaced by a 1.5" x 1.5" 80/20 extrusion with a solid aluminum pillow block on it that is 2" x 3/4". The extra thickness from the PRS design is to allow for GW3 hardened rails from Superior Bearing and their correspondingly larger wheels. By pre-assembling the three components it should be stiff as a-----well you get the idea!
Leveling and making sure they are straight and parallel will be fairly straightforward. Original racks will be used but its time for pinions anyway. I got ShopBot standard endplates and an extrusion from Bosch for the Y. Again larger rails and wheels (already have the rails and wheels) and re-use the original pinion.
I also, given the parameters of the rest of the design, asked SB to sell me a y/z car with no motor or Spindle mounting plate and will, once it comes in and I verify some critical measurements, modify the wheel holes for the larger wheels or use a different size pillow block and make the adjustment there. For the aluminum spindle plate, I want to engineer my own for the final step in this stage which is to add a small spindle to the front of the Columbo mounted to an air activated linear slide for use as a drill.

The additional extrusion, thicker pillow bolock, and larger wheels on the x will raise the whole thing higher off the existing table height and my purpose of this is to raise the table base higher off the ground. The reason for the secondary spindle is to use it primarily as a drill and be able to rig up end panel boring. The overall goal is to end up with an easy 36" clearance off the ground to the top of the table surface so I can bore cab bottoms and stretchers for dowel construction. Also, of course, I can do all my Euro 5mm holes with the spindle/drill and cut faster and smoother with a 1/4" bit for back dado and parts cutout. I'll post some shots shortly and if any of you other PRT guys would be interested, I'll send you parts lists as it is updated. As things are being wrapped up I'll also put on the Columbo speed controller.
A special thanks to Ted who helped guide my needs and some explanations of the current engineering through SB.
I'm really going to enjoy bugging him when this is done to work out a functional toolchanger!!
It may be easier to sell my rig as is and just buy a new one but then there's no fun involved.

[bleeth]

Well, we're really moving now! A friend of mine volunteered to drill and tap the 1/2 x 2 aluminum flat bar for mounting my new hardened rails for the x axis since he has a custom metal shop and I always use his services for bar rail, sneeze guards, custom metal glass racks etc. Dropped off the rails last week and a couple of days ago he brought them by. He not only did all the drilling and tapping for me but he picked up the cap screws to screw the rail to the flat bar and had it done for me!! Unfortunately the holes to bolt it down to the extrusion were 3/4" from the wrong edge of the flat bar!!! He's taking care of it but I really feel bad for him. These guys are known for their absolutely gorgeous and perfect metal work and this is the first time in over 10 years that something wasn't right.
The Y beam came in from Bosch Rexroth via UPS about a week and a half ago. You would think that a 67" hunk of aluminum that costs as much as this would be packed for shipping, right? Wrong. Several large knicks and a huge ding on one corner knocking the whole thing out of shape!! Well the distributor got ahold of Bosch, Bosch had the beam picked up and sent out a new one in a day. Great service. Not only that, but the distributor came by a couple of days ago and had the Bosch Factory rep (who definately knows Shop-bot-He saw an endplate in my office and immediately asked me if the part was for a SB) with him. I told them how great I thought their customer service was and how nice it was that they stopped by.
So today after normal hours I finally started putting parts together. Tapped out one end of the extrusion for the M-12 bolts, screwed on the end plate, got out my machinist square and checked it out. Perfect! We're cookin now! So I'm standing there looking at the beam and sliding a bunch of T-nuts and springs in it for the y flat bar and looking at the bot and after looking back and forth a few times I take a measurement. The beam is 69 7/16" long!!!. Go in the office, turn the computer back on, check out my parts list and sure enough-part ordered was 67 3/8"!!! Called the rep. First question he asks after hearing the issue is "What's my tolerance if he knows a local machine shop to cut it down". I wonder what part of 1711.25mm and absolutly square he didn't hear!!

I will say that the GW3 size v bearings are a bear and I reccommend doing the other minor modifications to use them if you ever need to replace your bearings at least on the x.

Stay tuned for more fun and games as we continue on the path of ever better botting!!

[ken_rychlik]

Dave, Take us some pictures. I am running a prt daily and am very interested in your progress. I had thought about building a machine before I found this one and still have a notion to do that.

Kenneth

[bleeth]

OK-Here are a couple before shots to kick it off. Previous mods are:
1. E Chain on Y
2. Hardened rails over existing steel
3. Upgraded Control Box to Dirk's "Hot Bot" (Forerunner of the 4-G)
4. 8 zone vacuum grid with 1" PVC pipe and valves.

548

549

550
Besides the gantry and x-rail replacement I'll be redoing the PVC to at least a 2" system. The increased volume will enhance the current holding, which is pretty good with the 7.5 regen blower but has room for improvement. The Hardened Y rails, e chain, and a couple of other things will be recycled along with the motors and spindle.
Next shots will show some in progress stuff. Most likely parts on bench.

[jon]

Dave, I just replaced the rails on my PRT alpha, with the BWC hardened y2 rails that were suppposed to come with the dual vees that we all have on our machines. I've seen tubular rails with semi circular cars elsewhere on this forum, and really wish I had been looking there first. One thing I did, in addition to the rail add on, was have the cast iron side beams the rails mount to milled flat on a very large upright mill (forestry machine shop had a 40 foot upright mill!), and it allowed me to mount the factory bent rails and hardened rail combos directly without shims. I believe this eliminated a lot of vibration, and need for shimming.

[bleeth]

This is it-all parts on hand, toolbox ready to go-local temperature heat index over 100 and predicted to stay that way-3 days to get her done by Monday AM.
Large coffee in the morning and away we go! Even I don't believe it!!

[Gary Campbell]

Onsite QC inspection scheduled for Fri the 9th, late afternoon ;)

[bleeth]

Viewing tickets available at the discounted price of 2 green bottles from Holland (Unopened)!

[gc3]

Watching this thread with great interest!!!

Attached is a virtual "cold one"...enjoy

Gene

[bleeth]

Midday Saturday: Torn down. Next step is to remove the racks from the x rails for recycle onto the new rail assembly. I already took the rack off of the Y gantry and it was easier than I thought it would be. The biggest thing I'm going through is all the memories of the original assembly. Although it has been moved several times it has never been taken apart. Even when I put the hardened rails on the Y I just blocked the Z up and never really took it apart!!

The old mounting holes will work but there aren't enough of them to suit me so I'll be adding another between each existing pair. You can see the end of a new x rail in the picture I used a pillow block of 1/2" aluminum to mount the hardened rail on and attached it to a 40 x 40 mm extrusion.

By the way-to get the large picture I just took the shot in fine mode with my camera, opened it in Adobe Elements, and saved it in a smaller resolution without changing the overall size. This may be the first time I posted a picture on the new forum.

[ken_rychlik]

I like the wonderfull custom e-stop mounting system you have!

Kenneth

[bleeth]

Yeah-The penalty of having it located in such an accessible location has been having it creamed umpteen times by rolling stock carts. I'm amazed it still works! Funny thing is-in all the years we have never used it once. All users race to the space bar if they want to stop it quick.

I have my first construction challenge. Somehow a math miscalculation led my x rail spread 1 inch narrower than the distance between wheels. I have a choice of putting a pillow block (1/2" x 2" x 10') under the extrusion and offsetting the mounting of it, using spacer washers between the gantry plates and the wheels, or having the y extrusion milled down 1 ". They all have their plusses and minuses. The quickest solution is obviously longer bolts and washers but the concern is how much stress the bolts would be carrying. They are 5/16" and 1/2" worth of unsupported length seems a lot. The other two means due to no weekend supply the project is postponed and we have no cnc next week. That would be a problem businesswise.
Anyone with enough knowledge of the bolt strength think this would work?

[gc3]

Grade 8 bolts come to mind...and maybe fender washers if possible. The extended bolt will get you running for Monday...maybe you can schedule a better "redo" at some point soon.

Gene

[ken_rychlik]

Given your choices, I think I would shorten the Y pieces.

Can you show us a picture?

Kenneth

[bleeth]

The extended bolts will put the motor pinions out. I can deal with that on a temp basis but not long term. I'll put them in for now and add the width via the wider block under the extrusion for a permanent solution. We'll see what challenges tomorrow brings!!!

[gc3]

Photos pls if possible, thx for the updates...

Gene

[bleeth]

OK: Got the extended bolts and verified it will work but will also require moving the pinions out on the motor shafts. This will be temporary as I will pick up a new top pillow block that is 2 1/2" wide and replace next weekend. This will be fairly easy instead of modifying the gantry to be narrower (don't want to lose an inch of y travel) or adding a block underneath (too much teardown to get there. My original numbers were correct but my metal supplier had 2" on hand and when he volunteered it for almost no cost I figured it would be wide enough for the extrusion and the rack but forgot why I had originally called for 2 1/2". The penalties of a project going on too long or maybe the failing memory of a "Senior" member!!

Here's a closeup of the current pillow block, a wheel with the spacer washers, and a wheel without. You can see that the larger diameter wheels (number 3's instead of the SB 2's) from Superior bearing required a bit of trimming to the gusset-easy to do since it was not fully assembled when I figured that one out.

[ken_rychlik]

How did you come by the prs gantry?

You can use 3/8 grade 8 bolts without the cam adjusters.

Kenneth

[gc3]

Does the 8020 run the length of the c channel? Did you attach the 8020 only where the old rail holes were? What will be the new hold down for the Y car?

Gene

[bleeth]

1. Bought end plates, gussets, motor plates, and z from SB. Extrusions and extrusion nuts from Bosch-Rexroth, hardened rails and wheels from Superior.
2. Getting metric around here is pretty easy. During the week there is a nut and bolt distributor, limited but regular stock at Ace Hardware, and highly limited at the orange store. I have bushings for the wheels and the right size is 8mm like most of the extrusion bolts.
3. Yes-10 foot of 45/45 for each side and 400/800 for the beam. The beam was an adventure since the first one came damaged and the second one too long! The Bosch distributor did all they could though in the way of customer service and picked up the tab for a local machine shop to cut it to the right length and mill it square.
4. I added new holes in the steel beam centered between the old ones and drilled them just a little oversized for some adujustment. The control side has always been the Y-0 as one of my original beams was not "sterling". The high side I took quite a bit of time test fitting and lining the new holes up with a laser. If you ever need one and can afford it Pacific is the way to go.
5. Since the rail is on the 3/4" pillow block I plan on hard bolting the motors. That will give me the same hold down as SB.
I'll find out tomorrow (hopefully) if that works. There isn't much original engineering here. The only real change from SB standard system is the x wheels. I just wanted to do it myself from assembled parts for the exercise. It probably would have cost me not too many more dollars but a lot less work to just buy a full conversion gantry from SB. Ted and Frank have probably been chuckling over it for a while now since I first started talking about doing it this way with Ted at Gary's camp a couple of years ago.

Speaking of the orange store I need a few bolts and some hacksaw blades and left my wallet home. I'll skip ahead of the order I was going to do things and do some gantry work out of sequence here cause a 1 hour round trip is too much of a *&&%#$* pain.

[ken_rychlik]

Wow, I am thinking the trip to california and paying 1500 difference to get my prs and sell the prt was a great deal after watching this take place.
Kenneth

[bleeth]

If I had seen a PRS with 5hp columbo that I could get for 1500 more than I could sell my PRT for I would have grabbed it too! But I bet with cost of trip added in as well as time away from shop real cost is the most relavent.
Of course-If I was going to wish I would wish for a Haas with toolchanger! Or since we are implementing e-cab a Thermwood.
Naah-I would have grabbed the toolchanger that Gary got instead!! I'm just a sucker for Bots.

Note that much of the delay from conception till now was due to many other priorities along the way.While planning this we also accumulated forklift, Holzer edgebander and sliding table saw, Delta RT31 cabinet saw, and moved to a new shop which needed complete outfitting electrically as well as wall work.
This project is a pain in the neck in many ways but it is also a load of fun.:D

[ken_rychlik]

Ya, the trip along with everything was a pain, but it was in the winter and I wasn't busy then, so the timing was good. i still didn't get a spindle though. Both of them had routers.

I have been thinking about upgrading to alpha and spindle, but then I may as well go with a tool changer, and then my vac hold down won't be enough, so the little upgrade gets real expensive in a hurry. lol

I did find on my prs that shimming the rollers in and out on the gantry was a better way to square it than trying to keep fighting with the gantry bolts. It stays square now.

Also don't get the gantry to close when you move the rails out. The motors\shafts or gears will hit the aluminum if you aren't carefull. Mine took quite a bit of tweaking.

The new frames are weaker than your old steel table, so you will end up with the best of both worlds when you are done.

Kenneth

[bleeth]

You are so right that one thing only leads to another. That's why I did this the way I am. I own the machine outright and didn't want to start another round of financing as much as I would like a new alpha. This economy and the narrow profits in it just can't justify it. Accumulating the parts bit by bit has made it a minor out of pocket expense and when I am done, I'm done.

[gc3]

Why did you go with an extrusion on top of the c channel, for the new y car?

Gene

[bleeth]

I wanted to use hardened rails instead of the old mild steel that has a lot of miles on it. The new system needs more accuracy in straight and level so the combination of the hardened rails, heavy aluminum pillow and the extrusion is more precise. The rail is sized for the larger wheels I wanted to use as well. All together with the previous gecko upgrade it more closely mimics a newer model. Looks cool too!
The overall object of the exercise is to cut more accurate box parts faster and eliminate all saw work with the possible exception of the 1/4" backs.

And one more thing now that my work day is over:

HAPPY 4TH OF JULY EVERYONE.

[gc3]

I wanted to use hardened rails instead of the old mild steel that has a lot of miles on it. The new system needs more accuracy in straight and level so the combination of the hardened rails, heavy aluminum pillow and the extrusion is more precise. The rail is sized for the larger wheels I wanted to use as well. All together with the previous gecko upgrade it more closely mimics a newer model. Looks cool too!
The overall object of the exercise is to cut more accurate box parts faster and eliminate all saw work with the possible exception of the 1/4" backs.

And one more thing now that my work day is over:

HAPPY 4TH OF JULY EVERYONE.


Thanks for the updates...

Another cold one your way via the net,,,

Gene

[Gary Campbell]

Dave...
Looks good. I am tuned in on the progress. :)

Looks like Gene got "el nombre del cervesa" correct this time!!

[gc3]

Dave...
Looks good. I am tuned in on the progress. :)

Looks like Gene got "el nombre del cervesa" correct this time!!

..hey

que bueno que hablas espanol....

pues quiero decir que los pacificos frios son los mejores en el mundo :eek:

Gene

[bleeth]

Heineken es el mejor pero si estoy en México es Dos XX es para mí!

[gc3]

Heineken es el mejor pero si estoy en México es Dos XX es para mí!

So how is it running?

Tenemos un dicho aqui...."no importa cual tipo de cerveza...lo mas importante cosa es bien helada!"

Gene

[bleeth]

Well it aint up and running but I did get the y rails done, z slide hung, gantry on the table, and the first section dialed in for level and 4 wheels down and rolling with no mechanical hold down. Of course, whether it is square or not will only be determined after it is running. The larger x wheels means minor modification to motor mounts and of course, after drilling and tapping 40 holes in the y rail pillow (Boy am I glad I learned how to do that with a drill motor) the first hole I go to tap on the end plates the tap shatters!! And the new screws supplied to mount the motor to the plate are a different size to the motor boring so that will be my next round of needed screws.
Could have been better but could have been worse. Looking downhill now anyway.

By the way-you are so right-time for a cold one.

[gc3]

Photos?

Gene

[bleeth]

Well, the week was too slammed with client needs to do much but today was back at it and at this point it is fully assembled and motors hooked up and running. Tomorrow I'll re-hang the spindle, customize some brackets for my old style Prox switches, tie down the wires and check for Y square-Then the fine tuning begins!!! Yes there were some additional challenges but that's the way it goes. All in all not as smooth a project as I hoped but nothing horrendous either. When I'm cutting parts again in a couple days but doing it 2-3 times as fast the problems will seem like nothing in comparison to the rewards!!!
You never know-Next time I may build a welded machine with Linear slides and get an Alpha developers kit from Ted-Know that would be a trip!!
If you would like to see pictures go to The SB site and look at a PRS but picture it on a steel frame!! LOL: I'll shoot a couple tomorrow.

[bleeth]

Up and running-Sort of!! Everything is back together and it seems to be running OK. It certainly runs up and down the rails a lot quieter and generally smoother than it did. Jog at 10IPS from anywhere to anywhere and all is well. There is more space between the table and the spindle (anticipated) so I will be raising the table with more bed under the existing ply. I'll also be shifting it as I ave around 4 1/2" to prox at Low x and very little past 97 on High. I need the opposite so the drill will hit more table.
Also the Z motor is turned around so I had to either reverse a couple of wires or change the z value to a negative.

I have a jog loop test routine and when I run it after a circuit or two it loses steps. I expect I'm not quite square and that will be next. Also my old x stop blocks need modification. The tapped in bolt routine is fine for the Y but x needs more sophistication.

I wonder if there is such a thing as "really done"

Here are the promised pics.

[bleeth]

OK-Just one more picture for now. I went ahead and ran a sufacing routine on it. I thought I had z pretty perpindicular to the table before but what were really tiny ridges are now gone and you can see from the level that even my anal attitude towards level should be well satisfied. A pretty good day.

[gc3]

OK-Just one more picture for now. I went ahead and ran a sufacing routine on it. I thought I had z pretty perpindicular to the table before but what were really tiny ridges are now gone and you can see from the level that even my anal attitude towards level should be well satisfied. A pretty good day.


Good for you Dave!!! Looks like 2 green "uns" are in order...

So I see a fan(not me) in the background that looks like it is running, is that part of the new dust collection system?

I hope that level is not part of the series..."The Empire Strikes Back"

Thank you for posting photos!!!

I am still looking for used parts for a hybrid bot machine. I got some Igus cable carriers cheap on e bay today...3"x1.5"X96"...$25

Gene

[bleeth]

That fan, as well as the 6 others in the shop, is how we push 102-108 heat index air around to fool ourselves into thinking they make it feel better. I believe you should see some PRT parts in the background of a shot or two.

[gc3]

OK after looking at photos XXXX times I see some parts that look ready to ship south...;)

Dave a 2 ton split AC in the shop will make life a "breeze" :D

Life is funny...here in Los Cabos it is mid July and high temps are at a all time low...80 today with lows in the high 50's....WOW to think those temps in July.......in Mexico/Tropical Desert....2012 :eek:

[bleeth]

Well we made "real" sawdust today!! Re-did the vacuum holddown to 2" PVC and cut and sealed a new plenum on a thicker built up base to make up for the higher height of the z during "spare time" last week and spent the weekend tweaking, checking, squaring, testing, re-tweaking, re-checking, re-squaring and re-testing and then doing it some more.
No matter what I did I couldn't get my looping jog test routine to work smoothly at high speed (8-10 ips) for extended periods so by Sunday afternoon I decided to skin the one side of the spoilboard so I could wrap that up this AM and get to some parts and just lower my jog till I solved that issue.
It seemed incredibly wierd as I have been jogging at 10ips for years and other than a firmware update made no system changes whatsover in this entire process. I'm still running 3.5xx. All ideas are welcome.
Talked to Gary and Dirk. Gary suggested checking comm rate with the SB diagnostic and RAM. This computer has been running my SB for so long it seemed like a non starter but I did anyway. 460k ram on the system readout and 56% comm! Whoooops :eek:! Dirk says high speed serial card and serial cable probably isn't the culprit as it will transmit as fast as anything including USB-2 (or so this techno-ignorant soul was told.)
Either way, it obviously needs more RAM and I'll check out if I can add it to the existing board.
In the meantime we needed to cut some parts. First was a quick template for some radii so I drew it up, threw a 2 x 2 on the table, turned off 7 zones (I have 8 @ 2 x 2) and cut at 3ips with 3/8 compression (2 passes 3/4 MDF with p-lam 2 sides) with no board movement and smooth part. That means vacuum system way improved and cutting nearly twice as fast as before. Edges came out perfect and checking radii against store-bought corner set showed matching size. Noticed at z-zero routine to spoilboard that even with all zones open could feel plate being sucked down. That was a new one to me but since then others told me they were used to that. What else have I been missing??
We'll be cutting some Corian and cab sides (Lam on plywood) tomorrow but will push the limits on some scrap melamine first before I raise speeds much more.
Our current project is all FSC and formaldehyde free plywood with LEED point chain of custody back up and that stuff costs way too much to play games with!!
Next is the DC and drill, but I promised the crew to get the domestic compressed air system piped and air dryer hooked up first.

[gc3]

Congrats!

Ebay...new computers are cheap...it's 2010 and that technology grows crazy fast...even a refurbished off lease one will crank that baby up!

http://cgi.ebay.com/1-FAST-HP-COMPAQ-DESKTOP-PC-COMPUTER-2-WIN-XP-3-PRO-DVD-/190420566865?cmd=ViewItem&pt=Desktop_PCs&hash=item2c55f34351

I got this same one 2 months ago and my antique jogs/cuts at max speed...a whopping 6IPS XY 3IPS Z :eek:

Pack those parts well, it's a long way from Fla to MX!

Have a cold un on me!

Gene

[ken_rychlik]

I would also suggest to get everything cutting square and mark some place on the rails where you know the gantry is where it needs to be.

Then loosen up the motors to where they don't touch the gear rack. roll the gantry around and then take it to your marks and see if under a free roll that they come back to the same spot.

I adjusted the bearings by shimming in and out to make sure it was "comfortable being there"

My jog speeds were able to be bumped up after that. If the motors are struggling trying to keep it square, it won't jog fast either.

At least mine didn't.

Kenneth

[bleeth]

OK-I have squaring down and will get to the computer issue. The cab parts we cut today have clean and square edges, are perfectly square, the perfect length in the x direction and undersized by .05 in the Y!
A milled steel straight edge and digital level confirms that y rail is flat and straight. Also, .475 deep holes bored with .197 bit are .204 in diameter with one peck. Spindle is vertical when checked with digital level. This is a code line for cutting out the part with the same bit:

M3,1.000000,15.098450,-0.780000
CG, ,0.901550,15.000000,-0.000000,-0.098450,T,-1

It is generated by Artcam. For you code readers-do you see a problem here?

[gc3]

.007 larger hole...for me that would border perfect...

Have you checked spindle run out with dial indicator? maybe change to a new collet and bit and see if you get same result.

[gc3]

OK-I have squaring down and will get to the computer issue. The cab parts we cut today have clean and square edges, are perfectly square, the perfect length in the x direction and undersized by .05 in the Y!
A milled steel straight edge and digital level confirms that y rail is flat and straight. Also, .475 deep holes bored with .197 bit are .204 in diameter with one peck. Spindle is vertical when checked with digital level. This is a code line for cutting out the part with the same bit:

M3,1.000000,15.098450,-0.780000
CG, ,0.901550,15.000000,-0.000000,-0.098450,T,-1

It is generated by Artcam. For you code readers-do you see a problem here?

So did you get this figured out?

I am still interested in the used parts.

GC

[bleeth]

The problem is mechanical on the sizing. After I got the Y rails right the torque of operation nudged it back out of flat. I'll shim them instead of trying to hold them in place with "tight" bolts. I have 3 slots in computer and am picking up RAM today. Probably be next weekend till I get to Y due to schedule, but in the meantime we are cranking out parts and making minor adjustments as production schedule right now is heavily loaded.
I put new collet and collet nut on but I think the hole is getting sized out by slightly out of plumb spindle. I'll hit that after Y is dialed in.

[bleeth]

With the new 2 gigs of ram comm speed went up to 71.5. Had a bunch of tweaking needed to get her smooth but finished that this morning and was still losing steps on a looping aircut program I wrote years ago when I first put in the Gecko Board. Drove me nuts!! It would make a couple of good clean loops and then suddenly lose steps in both axis. Time for a call to Frank. He figured out that the looping speed test had all move speed in it and suggested that due to the different resolution of move and jog in the software I was just trying to move too fast for the weight of the new gantry over the old. I redid the file so that all the straight line moves were jogs and the couple of arcs were moves, set jog speed to 9, move speed to 5 and let her rip. Around and around she went with nary a glitch.
Next of course we will be back to cutting parts.
So a question for those of you cutting cabinets on a PRS Standard with a spindle:
What do you consider your high speed for jogging and cutting? This is obviously different for Alpha guys and I am assuming the 4g type control board (Geckos).
For those who made the switch from SB 5.xx to the latest 6., did you notice any difference?

[ken_rychlik]

I have alpha on the way, but have been running my prs standard at 8 ips jog and normally cut at 3 ips with 1ips for the z.

That is with a router though.

Kenneth

[Brady Watson]

Dave,
3.6.x is a major update to communication and how it is handled via USB. Definitely pull down 3.6.18 and load it up, along with the firmware.

Your move speeds will be limited by 2 factors:

1st, you will be limited by how much force you require at a given speed. I would guess that you should be able to reliably cut most wood sheet goods in the 4 to 6 IPS range with full torque. Anything over 6 IPS, and you need to watch your ramping rates (hard, abrupt moves) and think about how hard you are pushing the tool thru the material. Your open-loop steppers have their most power at rest. They lose power the faster you go.

2nd, your communication efficiency may limit your move speeds over 6 IPS. The same holds true for your jog speeds. This is nearly entirely dependent upon your computer hardware. You should have a PCI to USB card installed in your computer, plus any self-powered USB hub. USB Card to USB 2.0 hub to USB to serial converter to control box (unless you have a v204 controller - then skip the serial converter). What's funny is I have been to shops that were able to pull 93% efficiency on an older (1.4 Ghz) Compaq laptop! The tool was limited to about 8 IPS when cutting (lack of torque) and topped out at 17 IPS on the jog. After the novelty of jogging 17 IPS wore off, jog speeds were reduced to 12 IPS to reduce wear & tear on the gearboxes.

The speeds I list for cutting (4-6 IPS) are considering the inherent nature of open loop steppers to lose position when pushed too hard. The higher voltage power supply of the 4G setup effectively moves the power curve of the stepper's useful range, higher up in the RPM range. It is a fantastic improvement over a 3G, but it still required discretion to reduce the chance of lost steps. Adjusting your VR values correctly will enhance the tools smoothness and give you a little more cushion when changing directions.

If you have v203 (red) Geckos, you should have faster speeds than the v202s since they dynamically 'shift' from microstepping to full stepping at higher speeds, reducing the communication load by a factor of 10.

This is probably more info than you need...but the lurkers will probably eat it up with their morning coffee.

-B

[bleeth]

Guys;
Thanks for your input. Quite helpful.

The geckos are v202's. Communication is handled by the same high speed serial card that was installed in the computer when the Bot-Rod was first hooked up. It's not much of a big deal to switch over to a USB system as long as putting the USB to serial convertor at the controller end doesn't defeat the purpose. I do wonder if it does have an advantage over the high speed serial card though. Obviously USB2 is far faster than standard serial, and overall the USB system of comm has supplanted serial in general use, but is it faster than a specific high speed serial card? I would hate to install 3.6, find out I had to run to compusa and redo comm as an emergency, and alternatively, although the cost of switching is low I still have a lot of other things to get done in that area of the shop, like getting DC ducting and dedicated air installed.
The other thing is SB recommends against hanging a drill off a PRS standard. What's the general feedback on that from anyone who has? I know I need to "customize" a bracket as the Columbo is larger than the HSD, but that's not much of an issue, it seems to be more a question of the added mass.

Dave

[Brady Watson]

Dave,
I don't remember what serial card accompanied the BotRod setup. I think it might be a Quatech if my memory serves me correctly? I didn't have good luck with the Quatech high speed serial hardware. It seemed that the SB liked to have the converter close to the control board.

You may want to try an IOGear USB to Serial converter. I think they are like $12 now if you shop around - then go USB from your computer to the converter.

I have probably posted at least 20 times on the 'recipe' for good USB communication, but I'll add it here again since you're one of us 'ol schoolers :)

You ideally want a 2.0 PCI to USB card in your computer. It doesn't matter if the motherboard says it is 2.0 or not. You should have a completely separate USB bus for the ShopBot in my experience, to eliminate issues. Dells are notoriously lame in the USB department. When I get a service call regarding comm issues, I tell them to buy the components listed here.

Then, you should have 2.0 self-powered regular old USB hub. These are cheap - $15-25 for one. This gets plugged into the USB PCI card you installed already. The reason for this hub is kinda behind the scenes. It opens up what Windows refers to as an 'Enhanced' USB channel - just by plugging it into the computer(!) - What this enhanced deal does is open up additional bandwidth (like a larger pipe) and improves both speed and reliability.

Then plug your 10 foot or less(!) USB cable & plug this into your IOGear USB to serial converter. Then do your software/firmware and do a communication speed test to check numbers.

Then you should be all hucky duck :D

SB's concern on mounting a drill on the Standard is that the 3.6:1 motors really don't have the cookies to throw that kind of weight up & down reliably. If you are going to do this, you must limit your Z speed, as well as replace the Z springs to compensate for the additional counterweight required to keep the Z neutral against gravity. Personally, I prefer a 2nd Z axis with a Milwaukee electric drill or laminate trimmer. If you are using an air drill, it is possible to make a bracket that gets you in the range the drill will use, off of the Y axis rail supports. If you have the extruded ones, it's a no-brainer.

-B

[bleeth]

Made the final tweaks yesterday AM which was just re-squaring after all the y and x rail tweaking, resurfaced spoilboard and then ran a couple loop tests. The limit was pushed into step-loss over 7ips jog and 3ips move. I ran several comm tests in a row and saw that it was generally barely over 70% and sometimes slightly under. Since I knew the ram was plenty it was an obvious conclusion that the question I asked was answered by performance. Ordered new parts last night.
In the meantime spent the rest of the day running parts at 3ips/6ips and all was perfect. By the end of the day I was being asked to run some parts that they were hesitant to run a couple of days ago. Our accuracy is now what I was after when I started the whole program.
FYI: I have a Belkin Hi-speed card, APC powered hub, and a PTC convertor coming. The necessary cords (short length since control box and computer live in the same cabinet) are inclusive and the whole thing is $40 including shipping. The Belkin (8 bucks) was recommended specifically by owners of old Dells!
It has definitely taken more than I anticipated going into this to get this far and believe me when I say that it was right down to the wire for us to have reliable parts production back on line. That being said, the overall project is well worth it as it forestalls the necessity of changing machines out altogether at a much higher cost.
I could have simplified it by simply getting the entire gantry and z from SB but despite the extra work entailed I am glad I went the route I did.
Next stops: drill, DC through the shop, and SB Link.
Thanks again to all that have contributed to this project with their encouragement, suggestions, and information. It is all invaluable.

[bleeth]

Well today the USB card, hub, and converter went in. Didn't have any more slots so replaced the high speed serial with it. Had some fun getting the drivers in as the DVD/CD player has been toast for ages and even though the player itself is good and the driver checks good it just doesn't work. Prayed a little and ran comm test and got the lowest numbers I've ever seen. Went into the usb in device drivers and found a menu to change comm and check speeds. Turned comm all the way up and the other one down per the hints on the screen.
Got back over 80%!! Ended up running 10ips jog test for 15 minutes with nary a hiccup. Looks like we're back to normal on jog and I can up cutting as well. Don't have time today to run jog test to the limits to see when it does lose steps but will soon. Looks like it's time to update SB software!!
It's definitely time for a green one!!!

[Brady Watson]

Good for you, Dave.

-B

[john_l]

Good to hear. I'm still tuned in to this one Dave.

[bleeth]

On another thread there has been much back and forth with Brady, Mike, and others. Going the 6k for a complete Alpha upgrade is out of the question. A good middle ground seems to be a stock PK296A2A motor with 3.6 spur gears wired half coil and a possible change of resistors. Although they don't have the torque of the 7.2/1 motor it is still way improved over my original motors. (I think I already have the resistors recommended by Mike and Oriental Motor but will have to check). Oriental would be happy to rig this with TH gears as long as I bought a hundred of them! Are there 24 more guys out there that would like to get in? LOL

We are getting perfect accuracy on parts and very smooth cutting. There is enough power going on now that the machine has "danced" across the floor 6 inches since the upgrade and so is being bolted in place.

The next step is the shop dust collection ducting and then I will do the motors.

I am still very pleased as my overall outlay is way less than a new machine similarly equipped after selling mine as it was and the ongoing learning experience is rewarding as well as fun!

[bleeth]

Well, for those who followed the thread regarding changing over to Belt drive PK299's you know I put together a fully engineered Cad drawing for the gear boxes, parts list, and obtained everything necessary to move on to changing out the motors but retaining my Gecko controller. And for those few who noticed in another thread (I forget where now) I mentioned that just as I had everything on the shelf I picked up a set of Alpha drivers for a very good deal from another botter who offered them here and changed my mind about the next path for the upgrade.
So here I am with all of those great parts, including the motors, for "plan A" sitting on the shelf but also the Alpha drivers. After some back and forth and quotes for what it takes to get a Alpha control system without drivers from SB I decided, once again, to do it the hard way and build my own Alpha control box using some critical components from Shop-bot and figuring out the rest on my own and with the help of some other friendly and helpful fellow botters.
I'm just a glutton for self-punishment!
I found a NEMA Enclosure on E-bay and it is in transit to me due for arrival in another couple of days.
Business also is allowing me to place some orders for the new control board, cables, and motors so it looks like the next upgrade is going to be taking my custom PRSish Bot and turning it from Standard to Alpha.
At the rate all of this is going by the time I am done what little hair I have left will probably be gone and I'll be announcing my retirement before I actually have the old girl the way I want, but in the meantime it sure is more fun than slamming together boxes for clients that pay their bills slow and rarely appreciate the work!
Stay tuned for the occasional update. Maybe even a couple of pics.

Dave

[danhamm]

Way to go Dave, don't you just love those crossroads..which way do we go now...lol..