New Machine Build- JGRO in basement (upstate NY)

[elseed]

All,


I have started a build on a JGRO design in my basement. I am using more or less the JGRO plans with minor modifications. I have attached three pictures.

One of the progress so far. I have cut my linear bearings using a metal blade in the sawsall with the vice holding the angle. I then filed the burrs. I cut a few of the MDF pieces also.

I also attached a picture of the casters and the cut pipe. This is an innovation as suggested to me by a pal of mine. The plan is to use these as my pipe aligners for the y axis at least. So the caster goes on the y supports and the threaded 1.75'' pipe threads into the caster. The hardware store that is orange cut and threaded them for me! The pipe is tapped to fit the bolts, and the 1'' y axis fits inside the pipes. We'll see how it works. It is heavier, but I bet a lot sturdier than MDF or plastic.

I added a picture of the modest tools I am using.

1. Cheap Router and table. Not sure if I want to use the router for my spindle
2. Aluminum straight edge - very useful for guiding the cheap circular saw
3. Drill press I got from Big Lots for $50
4. Sawsall
5. Vice
6. Shop-Vac, maybe I can use this as a dust collector later
7. My old high torque hammer drill - I have gotten a ton of use out of this thing

I have ordered my bearings from a seller on ebay:

608-2RS Inline Skate, skateboard bearings, ABEC 7. They came to $21. Seemed fair.

I plan on using 1/2 10 single start lead screws from ENCO unless someone has a better suggestion. These seem like a good price and I have read on this community that they work well enough.

http://www.use-enco.com/CGI/INSRIT?PMAKA=408-0220

I am planning on using couplers and anti-backlash nuts from dumpsterCNC. Unless anyone has strong feelings otherwise.

http://www.dumpstercnc.com/

And I plan on a 305 oz-in kit from hobbycnc.

I haven't figured out where to get the other items required such as flange bearings. Maybe mcmastercarr?

As usual any help or advice would be appreciated. Good Luck!

ElSeed.

[Glidergider]

I would suggest the 1/2 10 5 start. I have the 1/2 8 2 start on my current JGRO. it works much better then the single start you mention above. I'm building the 4x4 Hybrid, and on it, I'm planning the 5 start as Joecnc2006 suggests in his design.
http://www.mcmaster.com/
Part No. 99030A7041018 Carbon Steel Precision Acme Threaded Rod 1/2"-10 Acme Size, 2 Turns/Inch, 6'L, Rh ThreadIn stock at $55.77 Each

Increasing the starts will increase your low rpm top speed. Stepper motor's max power is at low RPMs.

You can get flange bearings from this place.
http://www.thebigbearingstore.com/servlet/the-68/1-fdsh-2%22-Four-Bolt-Flange/Detail?sfs=47e19780
It should work on both the X and Y axis for sure.

[elseed]

Glidergider,


Thanks for the information. I think that I will definitely use some upgraded screws for my next machine. This one I am trying to build cheaply to get my feet wet. But I really appreciate the information. I did not know that steppers give max power at low rpms.

Those flange bearings look great, thanks.

Elseed

[elseed]

Got my bearings today. I should have my linear bearings done this week!

ElSeed

[Glidergider]

Elseed,
I know exactly where you are, building a JGRO. I was there too. It's a neat place to be. I hope you have half as much fun as I've had with mine.

Originally Posted by elseed Glidergider, Thanks for the information. I think that I will definitely use some upgraded screws for my next machine. This one I am trying to build cheaply to get my feet wet. But I really appreciate the information. I did not know that steppers give max power at low rpms. Those flange bearings look great, thanks. Elseed

[emtffkev]

Did you get your bearings from a seller named Nextridge? I just ordered some bearings from him on Ebay and the price was very close to what I paid...

[elseed]

no, I got mine from bobhill5 on Ebay. He got them to me quickly.

They seem fine.

I made one linear bearing this last weekend. Man it takes time. I had some trouble getting the holes in the right place, I used my drill press.

And then I used a flat carbide bit on the drill press to try to route out the notch for the attaching bolt. I figured I could put the angle flat on my clamp and then slowly work it into the spinning bit.

It worked. But I can't help but think this was a rather hard way to do it.

[emtffkev]

I assume you are using steel angle...

The way I did it was to drill my pilot holes in the appropriate places with my drill press, then I chucked the tap into the drill press and got the angle and table as close to the tap as possible before lowering the bit. Open the top of the drill press and disconnect the drive belt from the pulleys. Now with one hand press down on the lever to lower the bit and get it touching the hole in the workpiece. With the other hand, turn the pulley that drives the chuck. This ensured that I got perpendicular tapped holes every time.

Also, be sure to use some sort of cutting oil to ease with the tapping process. I used some WD40 and it worked fine.

[elseed]

I am not dead. I had to put the old jgro project on hold for a while because I almost moved.

Anyhow, I didn't. And it is time to start up the project again.

I have done some hardware work, but this weekend I got my electronics working.

I have an old dell that I am going to use Ubuntu 8.04 with EMC2. I am also using the 305 oz-in package from hobbycnc.com with the EZ driver board.

I had to:

1. Install Ubuntu 8.04 (after installing 8.06 and then realizing that EMC2 doesn't work with that yet)

2. Put the board together. Soldering the PCB kit wasn't too hard. I did screw up one of the jumpers by accidentally soldering over the hole without a solder sucker handy. After a while I managed to get the jumper in.

3. Install EMC2

4. Modify an ATX power supply to power it as described on hobbycnc.com

5. test

I do not know what the right configuration is for this setup for EMC2, so I am using the step time and space of the default for EMC of 2000 ns.

My jitter is set to 15000 ns.

Does anyone else have the 305 oz-in motors with the hobbycnc EZ board?

Anyhow, it is shockingly working!

More soon, I promise.

Elseed

[NYScroller]

Where abouts in upstate Ny are you located? I am in horseheads.

[elseed]

capital district

[elseed]

I ordered my stuff from dumpstercnc today. Pricey, but I figure it would take me a long time to reproduce this stuff with the tools I have.

3 couplers - 1/2 10 for the enco leadscrews and 1/4 bore of the 305 hobbycnc motors
3 anti-backlash nuts for the 1/2 10 enco leadscrews.

I will let you know how they work out.