JGRO Pics Finally

[Jason Marsha]

Zoltan,
The supports are not perfect as I drew them with my rather poor CAD skills. The one with the 5 cutouts although not perfect are copies of each other.

Lionclaw,
Did you have a problem with stripping the threads while using the drill?


Jason

[Jason Marsha]

This file was created with Spalm's Spiro program for millimeters. Use nc-plot to check the path first.

Jason

[Jason Marsha]

Post some pics of your cuts. I got a free vector file of a bracket which I will convert, cut and post the results.

Jason

[zoltan]

Hi,

Thank you. I understand that you cuted everything in one pass, isn't it? What bit did you use?

Zoltan

[Jason Marsha]

The files were cut with multiple passes for 22mm (7/8 inch) thick material. In some cases I used 5 passes at a depth of 4.6mm, leading to the following: 4.6mm, 9.2mm, 13.8mm, 18.4mm, 23mm. The ellipse for the open sign in the first post of this thread was cut out in 3 passes of 7.4mm each.

The maximum feed rate I have used is 1016 mm/min (40"/min ).

The bit used was a Whiteside (RU2100) 1/4" upcut spiral with 1" of cutting length, and 2" overall length.

When the bits are new you can have a fast feed rate, as these bits just run through the wood leaving clean surfaces and fine wood chips behind.
Upcut bits will leave a little fuzz on the top of the cut which can be easily cleaned off with a fine sandpaper, however the bottom of the cut is clean.

Jason

[zoltan]

Hi,

Thank you again. I downloaded your files and run them on simulator and it run in one pass of 23 mm for all cuts, no multiple passes. This is the reason I have asked. I will look to the code itself. Thank you. Very nice cuts.

Zoltan

[Jason Marsha]

Zoltan
Use a perspective or isometric view (X,Y,Z) to see multiple passes you will not see it in the X,Y view. Only the files with "Fullprogram" contained in the name will show multiple pass in a plotter. To have 3 passes ,copy the original code and paste it twice underneath. You will now have three identical pieces of code, Edit the Z plunge in the second and third set of code to reflect your depth of plunge per pass, with the third pass having your finish depth.
eg

Z5.0 (First set of code)
Z10.0 (Second set of code)
Z15.0 (Third set of code)

Note that the program code only has the Z axis above the work at the beginning and at the end of the program. You will edit the code that was copied and pasted to ensure this occurs.

You will also see in my "Fullprogram" G-code the feed rates have been adjusted for the plunge and then readjusted to reflect the original feed rate. The reason for this is that the machine is not as rigid as a metal one, therefore if I plunge too fast the entry point will have a slight gouge in the material face.

Jason

[zoltan]

Thank you. I will do it.

Zoltan

[Jason Marsha]

Here is the bracket I promised. I am not sure how smooth the curves as I did no editing of the dxf file before converting it to G-code.

Jason

[Lionclaw]

Originally Posted by Jason Marsha Zoltan, The supports are not perfect as I drew them with my rather poor CAD skills. The one with the 5 cutouts although not perfect are copies of each other. Lionclaw, Did you have a problem with stripping the threads while using the drill? Jason

So long as I didn't run the chuck into the piece, the threads would work out just fine. The threads in the adjuster blocks eventually came out though and I went to UHMW PE instead of MDF. I threaded the PE blocks with the drill though too

[Jason Marsha]

Had to do some running repairs to the JGRO today, the bolts holding the aluminium angle to the MDF blocks had started to loosen up. After months of hard running I suppose they had to loosen at some point. The pics show threaded inserts in the face of the MDF, this was done since constant removal of the Z axis plate would have stripped out the threads eventually. if you are going to put threaded inserts into the face of MDF you must clamp over the hole with a c-clamp and then screw them in so as to prevent the MDF from seperating laterally, as it is very weak along the fibres.

Jason

[Jason Marsha]

I cut a simple design in my MDF drawer faces using the Spiro program that Splam wrote. I ran the code twice so that the router would clean up a tiny flaw at the deepest end of the cut. Maybe I should slow it down some more to 508mm/min (20" min). I scaled the smaller design up 1.25 times to get the larger design using NC-PLOT.I will get a clear picture of the error from another drawer face and post it.
I suspect the X-axis rails (attached to the Z axis) are weak and I may repalce them with shafting rod if the correct size is in stock at the metal supply.

Jason