I've been looking on this web site for a long time and finally am starting to build something. I decided on JGRO for a first machine mostly for the great detailed drawings, thank you for them.
I'm using Baltic ply, about 3/4 and 3/8, at least that's what it's supposed to be but doesn't quite measure 3/4 and 3/8. The ply was left over from another project.
I'm planning to use 3/8 rod and Lovejoy couplers. I have everything cut out except for the router bracket, haven't made up my mind what to use for a router. Any suggestions would be welcome. I also have most of the holes drilled and threaded, used CA to strengthen the threads.
I've built the torture, excuse me torsion boxes, these use 3/8 ply and 1/2 MDF for the tops.
I'll post some pictures next week.
The one thing I can't seem to find at least at Lowes Or 3 Home Depots in this area is the 1 1/4 aluminum angle. Can 1 1/2 be used instead or does that screw up alignment ? Any suggestions here?
I'm sure I'll be back with more questions, especially for the electronics and software. This is a great web site!
Wally

I've been looking on this web site for a long time and finally am starting to build something
I also lurked for a long time on this site before posting, then jumped in and built the JGRO. Learned alot just by reading all the great posts.

haven't made up my mind what to use for a router
I went with a "Trim router" as my first spindle. It's light enough that I didn't worry about the weight being moved by the Z axis motor. It's a 28000 rpm rated at 700watts. It cuts just fine at 50ipm, but I usually just cut at 30ipm.

Good luck with your build! Lots of people here have built the jgro and you can find many pictures of their machines on this site.

Don't forget to consider having some sort of dust collection. That's one area I am now working on.

Thunterman

The one thing I can't seem to find at least at Lowes Or 3 Home Depots in this area is the 1 1/4 aluminum angle.
Try your local small hardware store. I found 1 1/4" angle at a business called "Metal Supermarket". They specialize in small quantities of metal. You could also order on-line at http://www.onlinemetals.com/

Thunterman

Thank you for your reply thunterman. I gave up looking for the aluminum angle and used the "onlinemetals" site you suggested. By the way,what is the trim router brand?
Wally

By the way,what is the trim router brand?

I found a "cheap" trim router at the local Mernards home center. I believe the brand is "Tool Shop". It was only $28, so you get what you pay for. It's not a quality tool, but works for what I need it for. I will upgrade to a variable speed router in the future.
You can see a picture of the trim router on my web pages at
http://cnc.hobby-site.com/cnc.htm

Well, I've managed to get some assembly done, don't seem to be as fast as most of the builds I read about on CNCZone.
I'm using baltic ply and MDF skins on the torsion boxes, I'm also using 3/8-16 screw and Lovejoy couplers. I think I have all the machine parts and they're all cut out now. Lots more drilling and tapping though.
Any suggestions on electronics and software would be welcome.
Wally

Well, I've managed to get some assembly done, don't seem to be as fast as most of the builds I read about on CNCZone.
Nicely done! It may be taking you longer than some of the other people building from those plans, but, that's gonna be one nice lookin' JGRO CNC table. My JGRO table took me about a year from start to first cut. Lots of delays due to weather, work, family, the electronics, finances, etc., etc., etc. Take your time and do it right the first time. Looking forward to seeing more pics of your progress.


Very impressive,

HayTay

That's good work,very clean. It should be a very good looking router when finished.

Electronics:
I use the hobbycnc kit with my JGRO, get the 200oz/inch motors. www.hobbycnc.com


Software:
Mach3 to control the motors. www.artofcnc.com


Jason

Thank all of you for the tips and the encouragement. If all goes well, I should have some more pics by the end of the week, my garage (shop) gets full afternoon sun so my work days are short now!

Is the hobbycnc kit fairly easy to put together? Assuming average soldering skills?

Looking ahead (way ahead), would a 766 Mhz proccesor be able to run the software?
What operating system? Would ME work or would XP be better? The computer above has a pretty empty 30 GB hard drive and 256 MB memory, video is on the motherboard.
Wally

Mach3 only works with Win2K or XP. ME won't work. A 766 is on the low end, but might work OK. The only way to know for sure is download it and try it. It's fully functional for up to 1000 lines of code in Demo mode.

Is the hobbycnc kit fairly easy to put together? Assuming average soldering skills?


I put together a hobbycnc kit and it went together smoothly with no problems and fired up smoke free during the first test. The instructions were complete and easy to follow. I had done some soldering before but not much so I'd say my skills were average at the time.

Mike

Looking ahead (way ahead), would a 766 MHz processor be able to run the software?
I run Mach2/3 on a HP 500MHZ K6-2+ laptop running WinXp Pro with most of the services turned off. You can find a "tuning guide" for Mach3 that will show how to disable un-necessary services and other programs that will allow Mach2/3 to run smoothly. The 755 MHz computer should be plenty fast enough to run Mach2/3.

Thunterman

First of all, thank you for all your helpful inputs, I'll be using most of them, so keep them coming. I'm pretty sure I will use a hobbycnc kit, I used to be able to solder in the old days.
I've been plugging along and have the Gantry almost done, all parts cut and varnished. I still have to cut the grooves, not too good with a router though.
Wally

I'm still plugging along, will post some more pictures soon. Where do you get the spacers, like dtl 26 ? I can't seem to find anything! Soon as I get the spacers the Y axis should be done. I finished polishing the black pipe ( I know now why they call it black pipe) and it's certainly smoother now.
I also received the hobbycnc kit with 200 oz/in motors, and plan to use Mach3 as Jason suggested. Need to get my nerve up and start soldering.
Wally

Where do you get the spacers, like dtl 26 ? I can't seem to find anything! Soon as I get the spacers the Y axis should be done.
On the Y Linear Guide Assy (cnc_assy08) I used double hex nuts instead of the spacers shown in cnc_dtl26. The 0.012" (2 x 0.266 = 0.532 > 0.520) it's off isn't worth the trouble as it doesn't seem to make much of a difference when the machine is assembled/finished. If you start using a caliper on the nuts you'll find they are different thicknesses, anyway. If you're really worried about it you can measure a bunch of the hex nuts to find pairs of them that are closer to the 0.520" dimension called for in the drawings. Trust me, though, it's not really worth it.

Looking for the spacers JGRO used in cnc_dtl26 will drive you "nuts", literally and figuratively!

I'm glad to hear your still "plugging along" and await pictures of your progress. Keep up the good work.

Back again, a little more done, at least it's taking shape now. Thanks for all the help, HayTay for the nuts idea and Mike (mb 0978) for the pipe polishing idea. I used a hole cutter and duct tape for the coupling. my reach between the drill trigger and the end of the long pipe was maximum for me. The pipe polished up good and it's certainly smoother than the original pipe was.
The gantry slides very well but I still need to shim things up because the pipes are both at the limit of their adjustment holes.
Can't remember if I said this or not but I used knockdown furniture hardware to hold parts together, everything seems good and tight.
Next trick is to figure out how to use my router for the rest of the parts.
Wally

Some more progress, a couple of pictures of the x and x and z axis. just dry fitted, need to seal, ca threads, and assemble for real. I haven't settled on a router yet, I'm leaning toward a trim router - any recommendations? Or, am I going down the wrong path?

Another question, are the 1/4" dowels just pressed in or are they glued? These are used to reinforce the joints aren't they?
Thanks, wally

Another question, are the 1/4" dowels just pressed in or are they glued? These are used to reinforce the joints aren't they?

I never used the dowels when I built my jgro.

Don't forget to put a coating of shellac or paint on before your final assembly. Looking very good so far.

Thunterman

Another question, are the 1/4" dowels just pressed in or are they glued? These are used to reinforce the joints aren't they?
Thanks, wally
Here's a link to a post by JGRO, himself, concerning the 1/4" dowels:

http://www.cnczone.com/forums/showpost.php?p=14854&postcount=15

I just tapped my 1/4" steel dowels in lightly using the handle of a screwdriver (I always use the right tool for the job, obviously ;)). I didn't use any glue, the hole diameter/depth provided a sufficient friction fit to hold the dowels in place. I was high enough from all of the CA glue used to strengthen the threads in all of the tapped holes. I also wanted to be able to easily reclaim the steel pins and use them again once I built another table.

Thank you for the replies: Thunterman, I'm putting three coats of polyurethane on all the wood and the MDF skins. Also have used CA on all the threads, the high from the CA was pretty good I thought.
HayTay, thanks for the dowel info. Somewhere, in a senior moment I think, I lost sight of the fact that they are steel dowels!
Any ideas on the trim router? Or any other router?
Wally

Well, I'm back working on my project, long time out but thanks to threads like glidegider I'm energized again. Lots of excuses.
I do have the electronics done, thanks to Mike Beck at www.mikebeck.org . It's a hobby cnc package with 200 oz steppers. Mike did a beautiful job, one that I'm sure I couldn't have come close to. I know that many have put this package together successfully but I was leary of my soldering skills.
I'll post some pictures tomorrow. One question I have and I thought I saw this somewhere but I couldn't find it. Z axis assembly assy 11, how is assy 06, antibacklash assembly held in place? Is it just held in place by friction?
Thanks, Wally

On the Z axis its held by two slots in the MDF to which the Z axis rollers are bolted.

Jason

Thanks Jason, I got it now. Reviewing what's left to do now and I think the only things left is dtl 23 and dtl 24, They're cut but not drilled.
Her's some pictures that show the pieces that are done. I used Baltic ply as you can see. Sure wish that it had been exactly 3/4 and 3/8, would have made measuring a32351

32352

32353

32354

32355

32356 lot easier.

Wally,
Your machine is looking great, my next incarnation will be of baltic birch.
DT

That plywood construction sure looks nice. The dust of cutting MDF is nearly unbearable. Your plywood had to be better. It looks better, I know that.

Seems the ply is an absolute winner, if i hadn't start mine in MDF, this would be my option, your machine looks really great, can't wait to see the finish prod.

Thanks for the encouragement. I have MFD for the torsion box skins so know a little bit about the dust.
Now for a dumb (hate the word stupid) question: Where exactly does dtls 23 and 24 go? What are they for? Ok, two questions.
Wally

I was right, the question was stupid - just figured out where dtls 23 and 24 go.
I'm sure I'll be back with other questions though.
Wally

Also, it seems I forgot the holes and threading for the jack screws too - enough to drive a person to drink! Wonder what else I forgot? Oh well, tomorrow.
Waally

I was just reading an old thread and, I think it was tajord or HayTay, they said that JGRO's dowel holes were for metal removable dowels. I thought that was good info to pass along. Maybe someone else can confirm that.

Sorry it wasn't me, i actually assembled mine with wood screw, IMO all those bolts and dowels are not need as long as you clamp the MDF before inserting them, this stops the splitting, and use a good wood glue, but then the advantage of the dowels and bolts according to Jgro if i remember correctly was to be able to disassemble the whole shubang if necessary, i guess it's just habit using glue and screws being a woodworker.:o

I used metal 1/4 inch metal "dowels" , but they're not solid. Hope I never have to take them out. I also used furniture knockdown hardware in the gantry.
Wally

More help needed. I think I saw somewhere that 3/4 Delrin could be used for the anti backlash nut instead of the assembly shown in the JGRO plans. Is this correct? I'm sorry, I tried to find the reference but couldn't. If 3/4 can be used I think I'll replace the assemblies.
Took the gantry apart today and drilled, tapped, and CA'd the holes I needed to drill. What do the jack screws do?
Wally

Wallyh,
Yes you can and should substitute plastic for MDF. I just started a thread about Delrin vs HDPE plastics yesterday. Maybe you saw it. (http://www.cnczone.com/forums/showthread.php?t=33215)

Here's a summary of strength vs cost of three plastics. 12x12x3/4 inch.

Delrin 10 ksi, $53
HDPE 4 ksi, $17
UHMW 3.2 ksi, $16

Data taken from McMaster Carr. I bought the HDPE last night for my 1 inch pipes. For the 1/2 inch pipes I used a discarded plastic cutting board. 1/2 inch is to thin to achieve clearance for the adjustment screws, so this time I bought the thicker stuff.

Thanks for the answer, I didn't catch your thread, but just read it.
I used HDPE for my pipe adjustment blocks and Delrin for the anti back lash assemblies. My problem is that the back lash assemblies bind up enough so that the screw doesn't easily turn, almost doesn't turn at all. My thought was that if I could use a single piece of 3/4 Delrin I wouldn't have the binding problem.
Wally

your build is looking great. May I ask some questions:

1. What is the difference in cost for using baltic plywood instead of mdf
2. What is the white material you are using for the pipe holders/adjusters. And tips of drilling guided holes for them.

Thanks, and good luck with the build. Hope to see some cuts soon...

I had some baltic ply from another project and a local store, Rockler, has a two for one sale from time to time. I'll try to find my receipt. The thickness is a little less than 3/8(used for torsion boxes) and 3/4(used for the rest of the construction). It just means you need to pay more attention to measurements. The MDF is dead on 1/2 and 3/4. The ply is great to work with and the MDF kicks out a lot of dust. The ply taps real good too.
The white material is HDPE, a plastic type material. I'd like to build a complete machine out of this. I have a small tabletop drill press. I got my material at a plastics company and they cut the pipe holders and adjuster pieces for me. They were all square, my cuts probably wouldn't have been! I made a jig for each size and clamped the jig to the drill press, I used a forstner bit for the center holes. I repositioned the jig for the corner screw holes and since the pieces were square, all you had to do was flip the piece around for the four holes in each piece. Wasn't too bad once you positioned the pieces correctly.
Hope this makes some sense.
Wally

Another question, just put the gantry back together again after drilling holes for the jack screws ( how do these work?) and what are the 1/4" holes for in detail 21, gantry corner blocks? Are they for stiffening dowels? Thanks, Wally

33798

33799Well, I'm still plugging along. I have the Y axis lined up pretty good and it seems to roll very good. That said, I'm having a devil of a time with X and Z. For starters the size is off because the Baltic ply is 11/16, not 3/4. Can't be all of the problem though, no doubt me again.
Wally