[Jason Marsha]

Thanks for the link Mike.
I have not bought the Vcarve software yet Bob. I should have all the funds together soon.
Took a break from the repairs. Presently I am trying to eliminate a little binding in the threaded rod nut. The 5/16-18 seems to working much better in terms of whip reduction. I turned the rod by chucking a drilling machine on and it seemed to work fine.

Jason

[Jason Marsha]

Guess what guys, Super Klutz bent the rod and did not realize :withstupi (chair) :violin: . Its a very slight bend but enough to cause the slight binding I was detecting. Its off to the hardware first thing in the morning.

Jason

[Lionclaw]

I got my stainless from a local metal supply yard. Very nice stuff. 6' of 5/16-18 for $2.60.

[Jason Marsha]

I drool for that kind of price here in Barbados. The store I went into had a 6' length of 3/8-16 stainless for BDS $80.00 (US $40.00), they had no 5/16-18 stainless in stock so I settled for regular 5/16-18 at BDS $9.00 (US $4.50 ). The duties raise the prices of everything in Barbados.

Jason

[Jason Marsha]

After numerous interruptions I finally got the machine to the stage of speed testing. I still have to bolt up the leadnut to the gantry but the clamps will do for now. I got up to 70"/min using 5/16-18 rod with no whip , thats the fastest I will run for now as I cannot go much faster with Mach3 set to 35,000 pulses per second. Then again just for fun I will Mach 3 on 45,000 pulses temporarily just to see what speed I can achieve without whipping (a little grease a must for me on the leadscrew at these high speeds).

Advice to new builders of the JGRO: Go with the 5/16-18 threaded rod at least on long axis instead of 1/4-20. Use the skate bearings all over the machine not just for the runners.

Jason

[Jason Marsha]

Well I am back to cutting materials, however I may have to fashion another nut as the integrity of the replacement nut was compromised by a clump of super glue that got onto the lead screw and was pulled through the lead nut threads. It is working for now anyway bit I may consider a metal nut soon.

Good thing about a smaller number of threads per inch is that it allows me more speed from Mach3. I am jogging at 70"/min on the Y-Axis(long) with no whip.

Here is a pic of the first part cut after repairs. It is a motor plate. The reason it has 8 holes is that 4 holes in a square pattern will secure the motor and the other 4 which will be outside of the square of the motor base will secure the plate to the machine.

The bearing hole is slightly too large and I will adjust this in NC-plot if possible. I have lots of these skate bearings with flanges which were obtained from numerous raids on copier machines. The copiers also carry some of these bearings without the flanges.

Jason

[Lionclaw]

Looks good Jason. That cut is very clean. I've always had a problem with melting plastics. I'm guessing I haven't run at high enough feed rates.

What sort of feeds are you using on that stuff?

[Jason Marsha]

I was running at 1016 mm/min or 40"/min using a 1/8" straight bit and the router flat out (~25,000 RPM). This material is medium density but it cuts well without burning. An upcut spiral bit is best however as it ejects the chips quickly and they do not have a chance to clog.
I will try posting a video of the next cut.
Jason

[Jason Marsha]

Here is the plate with the bearing and nema 23 face plate to show how the holes are located.
The bearing hole in the centre now holds the bearing snugly after adjustment of the DXF file and then replacing the circle code.

The videos I tried to upload were too large.

Jason

[Jason Marsha]

I split the already short videos so lets see if this works. Sorry about the quality and absence of sound.

Jason

[johnm99]

What are you using to cut the plastics.... any recommendations for wood...
I have got my maching put together and after getting to this point I am finding it hard to nail down what to use as a spindle/cutter/router....

[Tony Mac]

Hi Jason,

Very interesting to see your machine in action on the videos. It seems to run pretty rapidly and smoothly.

Tony

[Jason Marsha]

The bit I used in the above cuts was a straight plunge bit, however, the best bit to use is a spiral upcut bit. I usually use whiteside upcut bits but any upcut bit will work.
These upcut bits work well for wood as well. I personally use an aging DW610 router, I have also tried a DW618 which worked like a dream. You will have to make a custom mount for the Dewalt router as they have a diameter of 3.5" .

Jason

[johnm99]

Thanks for the response...

[Jason Marsha]

Tony,
The machine runs well but could be smoother (THK rails. LOL). Vibration usually comes from the lead screw whipping, which I have now solved by using the 5/16-18 threaded rod on the long axis.

Jason

[Jason Marsha]

Here is the code for the motor plate in metric and imperial units.

As always check the code in a program such as NC-Plot first. The skate bearing hole is a snug fit as well as the holes for the #10 screws.

I have found that most NEMA 23 motor motor mounting holes accept #10 screws easily, a few of them however do not.

I cut my plate using the metric file, the imperial is untested but shows no problems in the plotter program.

If you look at the code it is just a series of loops, so change the negative Z values to suit your material thickness, dividing the the plunges into 3 equal depths.

Remember the spiral bits will cut best.

Let me know if they are any problems.

Jason

[Jason Marsha]

Post pics or videos of you cuts if possible.

Jason

[spalm]

Jason, are you talking to yourself? Maybe need some time off?

Could you post some pics of how you are using these new bearing plates?

Steve

[Jason Marsha]

Steve,
Just maybe I do need some time off. LOL :drowning:
I would like to see other machines making cuts of the plates. I will get the spacers for the motors tomorrow and show an example of mounting.
The configuration of the holes is quite simple, they are basically the corners of 2 squares at 45 degrees to each other.

Jason

[Jason Marsha]

Did a quick mockup of how these plates would work.
The MDF would be the section of the machine to which the plate and motor is attached.
As you can see the plate can remain attached to the machine while the motor is changed.
The screws for the motor do not protrude past the plate material.

Work is hectic right now so I will not be cutting as often, it should be back to normal in a month.

Jason