[bubbahotep]

I have a few basic questions about the JGRO design.

Do you glue any of it together or is it all bolted?

Do you need any special tools to put it together or can it all be done with a circular saw, hand drill, etc? (What I mean is, will I get halfway through and find out I need a lathe, mill, or other precision equipment)

What components will have to be ordered? (I have a Lowes and a Home Depot nearby for most of the basic stuff)

[Jason Marsha]

It would be best if you had a drill press even if its a small one. Its very hard to drill straight with a hand drill.

Small MDF parts would be best cut with a band saw or table saw, do not forget to compensate for the width of the blade.

Parts cnc_dtl02 are two identical pieces glued together.Same thing for cnc_dtl01.
Those are the only parts I glued. I did not build the torsion box bed support or the base support structure.

A 4 x 8 sheet of 3/4" MDF should finish the job.

Do not use galvanized pipe its very inaccurate. Black pipe should work. I however used seamless shafting rod, I am not sure if either store sells it.

There is no need for precision equipment. Hobbycnc sells motor shaft couplers.

When tapping MDF in the 3/4 face where it is at its weakest, place a 'C' clamp so that the clamp does not allow the hole to expand and split the mdf, moderate pressure will work. Tap slowly, removing the tap occasionaly to clean out the excess fibres. If you try to tap rights through the threads will be ruined.

Krazy glue can be used to repair stripped threads by coating the walls of the hole, allowing to dry and retapping.

Jason

[bubbahotep]

Sounds manageable then. Thanks for all the tips.

1a) Would you reccomend the 127oz or 200oz stepper motors offered in the hobbycnc.com kits?

1b) Is there a power supply I can just buy that will work with these? I dont know enough about electronics to start modifying a PC power supply.



2) Has anyone put together a part number list of everything they bought at Home Depot and elsewhere? It would probably speed up the acquisition of parts. (thats getting kind of lazy on my part, but just wondering)


I'd like anyone with tips for the first time builder, please post them. This seems like a somewhat daunting task. There are so many threads to read up on...

[carlnpa]

I built one of these as my first machine.
Use plywood instead of mdf, you will get a much better machine.
Use 200 oz motor, I had 118's just upgraded to 200's, much better speed and power.
The Hobbycnc kit with most of the power supply components is a good way to start if you really want to complete this project.
Get someone to make you/buy UHMW/plastic pipe adjustment mounts, one of the guys here is offering these, I may be making these also mostly because I am cutting alot of UHMW and have small pieces I need to do something with. Again, I just upgraded my machine, much better adjustment.
The material list with the plans is pretty complete.
Use self locking (nylock nuts) instead of regular nuts.
Buy the bolts and hardware in bulk from someone like Enco.
www.use-enco.com
Use 1/2x10 acme rod, again one of the guys is making zero backlash acme nuts at reasonable cost.
I could go on, many good ideas in everyones builds.

[bubbahotep]

Do the motor couplers hobbycnc sells work with the acme rod?

[carlnpa]

Bubba,
Look at my thread here on couplers and rod bearing support
http://www.cnczone.com/forums/showth...?t=7465&page=2
The 1/2 in lovejoy coupling will clamp securely on the acme rod with no turning of the rod ends.
Another time saver if you use plywood you can literally screw together with decking screws, no threading involved. (I screwed and polyurethane glued)
HTH
Carl