#Work Update 1#
Well, it has been a fun day. ~400 mask visors cut in about 3 hours. Three separate tests, hour long, changing method of loading, learning to be efficient.
Test 0 (no production cutting): Just figuring speeds and power. Settled on cutting at 190mmps @55% power. Note, that my CDWG tube has been limited in controller to 80% output, before the actual power setting is assigned to the cut, which makes it 55% of 80% of 80W total available power. I know its a bit confusing as i dont have amp meter installed at the moment and dont want to accidentally overdrive the tube. Meter goes in sometone this week.
Test 1 (First production run, 1 hour): I got a portion of the big roll rewound onto smaller tube to help me with setting up the production, as the whole roll weighs in excess of 300kg and is not really manageable for a single old me (2 burly blokes maybe :D). Set up a simple stand made of 2 trestles and a steel pipe through the centre of the roll. Only can use close half of the bed as Y motor is getting in the way of flattening fed in material, so had to resort to doing only 2 visors at t time, although 4 would fit just fine.
Used 20mm flat neodymium magnets for hold downs while cutting. 4 at the corners on the outside of the cut, 2 inside to keep material flat. First hour yielded 80 mask visors.
Comments on first run - OW MY BACK. Machine is too low for comfortable operation, it takes a while to setup new chunk of PETG and position magnets, all bent over.
Test 2 (second production run, 1 hour): Figuring out particular problems while cutting. One of which was reloading/positioning/clamping speed, repeatability, etc.
Magnets were not particularly good solution as theres lots of them to position, guestimate or “frame” every time. Decided to mask off some bits on the honeycomb to help me with positioning next cut in a roll, aligning/clamping went quicker after that.
Also, the fact that i need to manually move the head away from “start position” to pull the roll down without hitting it was anoying me some. Have to figure out a way for the head automatically move away in x direction after the cut to let me pull on the waste and roll down without hitting JOG RIGHT button on the machine…
Extraction was a major time wasting factor as i needed to wait for smoke/dust to clear until lifting the lid. On that later.
Still too much time wasted (in my opinion), but was getting practice in.
Managed 100 visors this run.
Test 3 (Production run, 52 minutes, with improvements mulled overnight): Last thing i did after test2 was to run a laser with lid completely up, disabled hatch safety switch with a magnet (here’s stupid ). Nearly all of the smoke went into the table right away, none of that lingering when hatch is down. Some wisps escaped but it was MUCH better completely open, even though i do have a chunky gap under the lid with it closed.
The whole smoke being slow situation prompted me to ask extraction questions here. Thought things over, nicked two chunks of 160mm sewer pipe, taped it in place of 160mm corrugated+100mm corrugated+120mm rigid pipe combo and put an external blower to suck on the end of that pipe. It is not sealed to the pipe at the moment - no flange on intake of that fan (it’s a small bouncy castle blower, 300W @240V). This whole new setup helps IMMENSLY.
Another improvement i made was to get rid of the magnet placing step, as it was eating into the run time and making my back go all OWWW… So, i took visor design, stepped it inside by 20mm and cut it out of 6mm acrylic to make hold-downs. Now i only got 2 things to place on bed instead of 6.
Ran this 1hr(*) run with hatch wide open, new extraction, new hold-downs.
Asterisk means i didnt manage one hour because i ran out of small roll 52 minutes in
This run i managed to near double the production to 180 per hour (well, 52 minutes).
Its obvious open hatch and hold-downs cut my cycle time in half.
Clean cuts. Lots of white dust though.
Dust only settles, doesnt stick, so only some warm water is needed to rinse visors away.
Today got the full remaining roll. Holy cow, that thing is heavy. Will do minor adjustments to some things and will probably manage 200+ visors an hour, running with hatch open, using hold-downs and having plenty of uninterrupted material to work with. Will report back after i finish later today.
On the left 2 stacks 100 each, middle 180something, right no idea
Thats sum total over all the tests i described here. White dust comes off with water, condensate not sticking.
Extraction “before”. Lots of “whatever” taped together.
Extraction “after”, all 150+mm diameter, straight.
Blower thing sucking on the exhaust. Not taped/sealed, just sits against the pipe. No flange, will have to come up with something.
This is my setup as it stands after Test3
, right before burly dudes with 300kg roll of PETG rocked up to my gate…
So, this is how it is now. Anyone got any suggestions ? Comments ? Advice ?