Guilloche!
Posted: Sat Aug 17, 2019 10:06 am
After being a guilloche gadfly for a long time I've actually made a couple of them, on a $200US Genmitsu 3018Pro (strangely with a 30x18cm cutting area...). Not great art (certainly not as good as Art's version in the video), trying to see what the little machine can do. The material is 22g (+/-) copper anodized aluminum from Home Depot, about 0.6mm thick, and the lines are 0.3mm deep on the square, 0.2mm on the lobed version. I'm using a 1/8"/3.175mm 20 degree flat V bit, a cheapie provided as a set with the router. G code came from Carbide Create. It's a learning curve, Art mentions in the video that the lines should be a mm apart, but a mm apart on a 15" laptop screen isn't the same thing as a 50mm cut part, the moose needs more training. Lots more tweaking of settings to try, and more practice until they start making sense rather than being knobs to twiddle.
Aluminum is a strain for the 100W (yep, about 1/8hp if being generous) 9K rpm spindle, really a 775 vending machine brushed DC motor with an ER11 collet shrink fit on the shaft. Being impatient I started off at around 600mm/minute and while that will work (the actual cut cross section is quite small) it leaves a burr on both sides. The second one was 0.2mm DOC and still too fast and detailed. Cutting the outlines, well, that's a sad story that we'll gloss over other than saying it took multiple g code generations and tweaking the DOC and total cut depth and rinse/repeating until getting through. Lost steps in the Z direction on the square design and the V bit, but not X and Y. The second was after an endmill swap to a 1/8" flat endmill (shoulda gone smaller...), still lots of passes and retries. Successful in the end, at least.
I found a possible problem, while exporting an SVG the viewer shows some gaps in a few of the lines. I have it saved on the laptop (this is a 12" chromebook, like it) and can upload if wanted. These were cut from DXF files. The lightly cut area in the square is from the router, wonder if the double sided tape missed a corner and it was a tad low, the spoilboard is surfaced flat, it made the proper passes at the right depth but didn't manage to cut all the lines. A minor annoyance, at least to me, was not having the settings transfer from inner to outer when hitting next, that might be a nice future option. I couldn't find a way to recover the settings or go back a level, suspect that's inherent to the wizard but being able to recover a prior design could be nice.
These cut fairly quickly considering the cheap (around $10USD on amazon), underpowered, spindle, around 20 minutes for the design and (need more power Scottie) for cutting the outline. Next CNC session will be making smaller and simpler designs to get both the line spacing, cut depth, and feeds and speeds (well, it can be PWMed but the full tilt no-load boogie is still reported at only around 9K, the cheap optical tach is in the northern moose shop 2000 miles (is that 2800km?) north so we'll leave it at not quite enough). Think sticking a piece of carbide in a pencil sharpener (a diamond cutter one...) and then grinding the pointy bit to half a circle for the engraving bit so it's a single flute. After that I can exercise my limited artistic skills, have a 12x24 (30x60cm) piece of material so lots of practice space.
If anybody cares I can do a little review of the router, summary is while it's limited it's a great little toy. Home switches sitting in an Amazon box, brackets will be cut out of a cheap high density polypropylene cutting board, but that'll wait until after some more guillocheing. Or maybe after I get tired of clicking the wrong direction on the virtual jogger and run it into the stops a time too many. Oh yeah, just because it's made of 20x20mm extrusion don't get 20x15 cable chain to sit on top. Found out that's the ID, not OD, and lets just say it's a little big for the application. Might soldier through, but will probably get Mr. Bezos to send something smaller and keep the big stuff for another project.
This is the first time I've tried resizing photos on ChromeOS, hope it turns out OK
Kirk
Aluminum is a strain for the 100W (yep, about 1/8hp if being generous) 9K rpm spindle, really a 775 vending machine brushed DC motor with an ER11 collet shrink fit on the shaft. Being impatient I started off at around 600mm/minute and while that will work (the actual cut cross section is quite small) it leaves a burr on both sides. The second one was 0.2mm DOC and still too fast and detailed. Cutting the outlines, well, that's a sad story that we'll gloss over other than saying it took multiple g code generations and tweaking the DOC and total cut depth and rinse/repeating until getting through. Lost steps in the Z direction on the square design and the V bit, but not X and Y. The second was after an endmill swap to a 1/8" flat endmill (shoulda gone smaller...), still lots of passes and retries. Successful in the end, at least.
I found a possible problem, while exporting an SVG the viewer shows some gaps in a few of the lines. I have it saved on the laptop (this is a 12" chromebook, like it) and can upload if wanted. These were cut from DXF files. The lightly cut area in the square is from the router, wonder if the double sided tape missed a corner and it was a tad low, the spoilboard is surfaced flat, it made the proper passes at the right depth but didn't manage to cut all the lines. A minor annoyance, at least to me, was not having the settings transfer from inner to outer when hitting next, that might be a nice future option. I couldn't find a way to recover the settings or go back a level, suspect that's inherent to the wizard but being able to recover a prior design could be nice.
These cut fairly quickly considering the cheap (around $10USD on amazon), underpowered, spindle, around 20 minutes for the design and (need more power Scottie) for cutting the outline. Next CNC session will be making smaller and simpler designs to get both the line spacing, cut depth, and feeds and speeds (well, it can be PWMed but the full tilt no-load boogie is still reported at only around 9K, the cheap optical tach is in the northern moose shop 2000 miles (is that 2800km?) north so we'll leave it at not quite enough). Think sticking a piece of carbide in a pencil sharpener (a diamond cutter one...) and then grinding the pointy bit to half a circle for the engraving bit so it's a single flute. After that I can exercise my limited artistic skills, have a 12x24 (30x60cm) piece of material so lots of practice space.
If anybody cares I can do a little review of the router, summary is while it's limited it's a great little toy. Home switches sitting in an Amazon box, brackets will be cut out of a cheap high density polypropylene cutting board, but that'll wait until after some more guillocheing. Or maybe after I get tired of clicking the wrong direction on the virtual jogger and run it into the stops a time too many. Oh yeah, just because it's made of 20x20mm extrusion don't get 20x15 cable chain to sit on top. Found out that's the ID, not OD, and lets just say it's a little big for the application. Might soldier through, but will probably get Mr. Bezos to send something smaller and keep the big stuff for another project.
This is the first time I've tried resizing photos on ChromeOS, hope it turns out OK
Kirk