Eek. Or if anything happens to the beaglebone (which is a perfectly nice controller, and more robust than a Raspberry Pi, but still subject to electrical and software issues).
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Yeah but he actually has one at home and has had it for over a month. And as you point out, the specs counter some of his ignorance of the details. There really isn’t any reason that a techno testing nerd didn’t know what he got wrong.
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Does that even meet European standards for e-stops? I feel like it doesn’t.
The glowforge could probably make its start button closer to an estop than that one.
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My Trotec doesn’t have an e-stop button either. If I see something going awry I have to lift the lid. I find the idea of opening the machine you’re trying to stop as quickly as possible to be a bit ridiculous, but I suppose it works so I guess it could be worse.
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Yeah. As is.
Although in theory… it would be easier to punch a hole in the sheet metal of the muse to add a dedicated switch, than it would be to change the plastics for the GF to add one.
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Does a laser cutter need to have an e-stop? It’s not like a heavy duty CNC machine where you could trap a limb and it is totally enclosed while running.
@dan has just said it is in the hopper: Print button to pause a print? -- It’s in the hopper, so it doesn’t seem like it is a safety requirement for approvals. A bit surprising as you want to be able to stop as fast as possible if there is a fire and don’t necessarily want to open the lid or reach over it to kill the mains. You want to turn off the laser and move the the head away from the flames ASAP and possibly keep the extraction going. Does extraction tend to fan the flames or extinguish them?
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I am not sure on the regulations , but every e-stop I’ve seen actually hard cuts power or stops the machine without software control. The moment you are adding software to interpret the button it makes its less reliabile inherently.
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The hopper item is pause-on-button-press, which is a useful convenience. Per the forum guidelines, we don’t want to discuss safety lest people take discussion here as the correct course of action instead of the manual.
–dan
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The 80w Rabbit at the local makerspace had a big red palm-smack button on top as well as a tiny recessed button on the control panel. Repeated testing consistently showed that the panel button stopped the laser more quickly that the palm-slapper. “Repeated” testing emphasized, as nobody could believe this was true. Staff eventually re-wired it as expected.
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One thing I found interesting is their water cooled laser tube. The water supply is external so that is a hassle. You need a pump and a bucket or a tap. Kind of limits where you can put the Muse. However it raises the question of what Glowforge is doing about laser tube cooling?
The other is “No Cloud Required” for working designs. So if you already have a working set of settings and a cut file you don’t need the cloud to run the laser. This could be useful for doing makers taking the laser to craft fairs and other on-site ‘prints’ of stock items.
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Your 
(Basic or Pro) will have closed-loop liquid cooling. No water bucket or external anything required.
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Thanks! I was just digging through some other threads for specs. Sounds like the Pro has better cooling but both Basic and Pro use a closed loop liquid cooler or some kind.
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I’m at work, so can’t dig through at the moment, but my understanding is that the cooling is better in the Pro and that both units will monitor temps and pause for cool-downs in an intelligent manner as needed (doesn’t blindly stop in the middle of a cut).
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Yes I think the Pro has some Peltier cooling as well. My best guess is the liquid cooling passes through a heat exchanger that the exhaust air passes through. Presumably on the pro the Peltier is somewhere in the heat path between the liquid and the air to increase the temperature difference. All pure speculation but in the vacuum of no information for 15 months one has to make things up.
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The “bucket” is INSIDE the Glowforge. Therefore it’s much better.
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Welcome, good to have more participation around here.
Enjoy the forum, there is a lot of creative inspiration to be had!
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Well, not exactly a vacuum…
These are from October 2015. No reason to believe that these have changed in the meantime.
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I would expect the peltier to have the hot side with heatsink to be very close to the exhaust port so you don’t generate a feedback loop with the waste heat. They aren’t the most efficient of items in terms of power so you’d best make sure the extra heat generated departs.
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We know the basic has an aluminium block heat exchanger that transfers the heat to the exhaust air. To improve the cooling performance you would split that in two with the Peltier elements sandwiched between to make the water cooler and the air hotter.
Yes but the temperature of the water in the tube is the critical thing, the temperature in the rest of the Glowforge doesn’t matter much. The exhaust flow is massive, so can easily keep it all reasonable cool.
The tube has to be kept at a temperature not much less than the ambient air. That is why you need the Peltier to increase the temperature difference. The hot side of the heat exchanger gets hotter, so heat is transferred to the air faster.
Yes Peltiers are a lot less energy efficient than conventional refrigeration, but overall energy efficiency is not a big issue here. The exhaust will be hotter than it would be as extra heat is generated by the Peltier, but that goes straight outside anyway. The important thing is the tube is made cooler with very little extra space used up. Also it should be more reliable than a mechanical compressor.
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The Basic uses a radiator to cool the closed-loop liquid system; the Pro adds a second, active chiller (the Peltier) that is indeed right before the exhaust.
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