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electrosteam
11th Oct 2016, 08:58 PM
We have manufactured multiple coasters in MDF on our Mens Shed Router.
Each coaster is 86 mm square with our logo and a surround line engraved.

The plan is to have the router operating during open days and offer to engrave a visitors name on a coaster and to give it to them as a souvenir.

But, we will not have prior knowledge of the name.

So, the following methodology is proposed.
While the router is engraving a name, a second laptop will be manned at the visitor reception desk.

Input Assumptions:
- existing hardware and software to be retained; Arduino Uno, Grbl 0.9j, UGS,
- Grbl does not have options for sub-routines,
- coasters consistent size with prior engraved shed logo and surround,
- metal jig providing rigid consistent mounting of coaster.

Prior to Router Operation:
1. basic Gcode sub-program written to set up cutter at clearance height above text bottom line at centre of name (text string),
2. separate Gcode sub-programs written for all 26 letters of alphabet with each width pre-determined and noted,
3. separate sub-programs written to position cutter at text start for names of width 1 to maximum achievable,
4. basic Gcode sub-program written to move cutter to convenient safe position to allow easy coaster exchange.

During Router Operation at Second Laptop:
Visitor provides desired name to be engraved on coaster, total text width is calculated using noted letter widths,

Gcode assembled by concatenating pre-written programs:
a. basic set-up - (1) above,
b. position cutter at start of text - (3) above,
c. first letter in text - (2) above, followed by each letter in turn,
d. basic safe position - (4) above.

Gcode program transferred from second laptop to machine laptop via flash drive and stored in folder of names.

UGS loads selected program from folder of names and sends it to Grbl.

Folder of names will grow so that eventually off-line Gcode concatenation will become a minor activity.

Comments welcomed,
John.

russ57
11th Oct 2016, 10:37 PM
I haven't had any specific cnc routing experience, but have used a vinyl etc cutter. We drive that using inkscape and a plug-in, pretty sure there are plugins for g-code. You can then take your 'background' add in the lettering and generate your gcode. May be easier than piecing together from lots of code fragments. Of course, the gcode generated may be less than perfect...

twopintsplease
12th Oct 2016, 07:14 AM
Have you looked at "Stick Font"

NCPlot - Stick Font (http://ncplot.com/stickfont/stickfont.htm)

its free I have used it and it works well, not on a router but A Cnc mill I assume the G code will compatible with your system

electrosteam
12th Oct 2016, 03:36 PM
Thanks for the link to NCPlot, looks very interesting and would be much easier.
I will trial it at home tonight.
John.

electrosteam
19th Oct 2016, 04:52 PM
Progress.
We downloaded StickFont1.1 from NCPlot and used it to engrave several names.
No real problems once we learned a few more lessons on how to operate our router.

The software seems to include simple kerning but does not allow text placed about a centre line, so it was a two-step process.
First generate a Gcode file with X=0, edit Gcode file and note last X axis cut, then calculate how far off the centre line the text string is, then re-do the Gcode generation with the X offset loaded.

Works a treat, but, the font we tried was RomanS and this does not produce proper curves for text 6 mm high with 3 digits of precision (mm).
It is all straight-line approximation.
Trying 4 digits of precision did not improve it.

For now, not a problem, but we will continue searching.
John

twopintsplease
20th Oct 2016, 08:19 PM
Glad it's going well, what is kerning ?

russ57
20th Oct 2016, 09:13 PM
Kerning is adjusting the spacing between letters to make it look even... Different letter pairs require different spacing.

-russ

rcaffin
23rd Oct 2016, 08:36 PM
This is built into Mach3 as a Wizard. Simple to use.
I was able to engrave numbers around a dial with it.
364836
Cheers
Roger