Tube replacement saga - let's vote!

It’s nice to see a pre-release being inspected to help everyone understand it a little better.

Would you or another Pre-Release holder be willing to throw up some pictures/video and a simple take on it in a new thread?

@karaelena @marmak3261 @markevans36301 @Jules @rpegg @rebecca

I know I left a few out but you are welcome too of course

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You are correct. Each laser tube output is slightly different. I worked in the laser industry for a few years. There are standards, and each laser tube must meet standards for output power, dispersion, beam quality (TEM 0/0), and angular alignment amongst many. But, generally the best quality tubes won’t be exactly drop in for the best power output. Precision engineering for the tube to be user replaced is possible. It would take the tube manufacturer to take more steps () in manufacturing and accept a lower yield (), but it would be possible. Maybe ship cheap alignment tools with the tube replacement kit. Also, they would have to engineer quick disconnect type fittings for cooling and other easy change and safety features that I deal with daily. - Rich


The power connectors should be simple. The coolant should be some kind of pipe connection and really it should be simple too. Or at least simple to solve/implement. And as far as access to the unit, those top plates could be easily made removable - they probably already are. Also, the fact that the tube is on the gantry makes it generally pretty accessible since it’s not hidden in some rear compartment.

I hear @takitus on the user incompetence issue.
But the counter-argument is that you and I fix and upgrade our PC’s precisely because we can. Or our cars. Or the washing machine. We’re not told by the manufacturer that they won’t ship us a part because we ‘probably’ fall into the incompetence category and that we need to the ship the whole thing back to them for replacement of a component, at our cost.

Telling us all along that the tube is replaceable and doing a u-turn at the 11th hour makes me angry. For a company entrusted with probably close to $100m to release a single product, the amount of features and commitments renaged on to date is disgraceful.


Can someone explain to me what the ‘liability’ issue might be? Is the concern that I’ll be clumsy and break the expensive machine, or the concern that I’ll be clumbsy and break the tube, which releases a cloud of toxic gas and, I don’t know, mercury all over my face and kills me? Because guaranteed I’ll be clumsy, but one of those two options is more acceptable to me.

I’m not sure I selected the right answer on the poll, because shipping the glowforge back is a complete and total deal breaker for me, but I’m willing to wait for a solution as long as it’s not a vague promise of ‘it’s in the hopper and we’ll think about it.’ I’ll wait another 6 months with a cheerful smile on my face, but only if there would be the promise of a viable alternative to shipping the thing back. That’s such a wasteful process – time, financially, environmentally, all of it.


There are some lossless fluid connectors out there that take up not much more room than the tubing itself. We use them on motorcycle cooling vests. Might lose a drop or two of fluid when connecting the jacket and disconnecting. That’s a solved problem.


I am guessing it will electrocute you

… Electrocute a lot or a little?


@erin I’m OOL, and really trying not to add to the noise today … but have to stop and thank you for making me laugh: Thank you!


There are simple safety features that can be built into any machine that deals with hazardous/high voltages (or any hazard). Liability is not really something to worry about with the proper engineering. - Rich



There are two circuits in play - a house (mains) voltage of 120V (or 240V in Europe) which can be but is not generally fatal. That’s the stuff coming out of the wall socket. It powers all of the motors, lights, etc. \

Then there’s the High Voltage circuit. That’s the one that gets stepped up to 15-25,000V. That’s what it takes to get the CO2 to lase.

There are safe ways to deal with it as all other laser manufacturers have demonstrated but just dropping a screwdriver in there could kill you too.


Spot on

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Well @m_raynsford is still alive so I’m assuming more than a 9 volt, less than and AED.


Yeah, that’s probably an unacceptable amount of risk for someone who can’t remember the screwdriver names.


Who would engineer the ability of someone to work on the thing with the high voltage on?!! Who would engineer the high voltage power supply or conductors with bare wires or connectors to drop a screw driver on to?!! Lets get real, no manufacturer of a consumer product has done this and passed any consumer inspection services. GF is anything but hap-hazard in their engineering of your laser system. - Rich


The problem here is things like capacitors. They store electricity until released or it dissipates over time, so even after disconnecting power, there may still be deadly amounts of power stored in capacitors that can be discharged.

Check out videos on Microwave Capacitor Discharge, and similar high power devices.


Similar to working on an old CRT TV or Microwave Oven with large capacitors and high power. Untrained people shouldn’t do it. A lot of us can, a lot of folks shouldn’t.


Um. Yes it has been done and is still being done. Open up most low-end (<$25,000) lasers and look inside. Run away from any of the <$5,000 Chinese lasers.

I have an LS600h that has a hybrid drive train in addition to the dino juice motor. Most everything for the electrical for the hybrid drive is separate and shielded but it’s also labeled with big “DON’T FREAKIN TOUCH THIS STUFF NIMROD!” labels. But despite the labels I can pop a cover off a junction and short terminals.

My old E350 had the same thing for the secondary braking control circuit (separate battery so if the main car battery died I’d still have brakes). That battery and lots of car circuitry was still live when the rest of the car was dead as a rock.

For the laser, high voltage capacitors store up and retain voltage for a decent amount of time. It’s required in order to produce the step-up. Just physics. Can they be potted so you can’t get a screwdriver in there? Maybe. But how much of an idiot is on the other side of the handle.

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Yes, I understand that (I think it was me that quoted that) & think that shipment + 12 months is ridiculous but that was in response to people near their offices driving their glowforges to the factory for replacement rather than shipping them.
My post here is my “None of the above - I’ll elaborate below” vote stating my opinion that shipping to the factory as well as asy further delays are both unacceptable to me. In my opinion they must come up with a solution that does not involve shipping the entire unit prior to the current projected shipping deadline.

Just speaking from experience, 277v hurts Really Really BAD. then you spend the rest of the day feeling like you are going to puke and your nerves are shot.

Fortunately I haven’t done 480v.


I work safety for HV systems everyday. Your analogy is not really like it is for modern laser power supplies. The rule is that there be that the energy storage capacitors have bleed down resistors that bleed the system down to 30 volts or less in the time it takes to access the circuit. Usually this is two minutes or less depending on the system. Even if the power supply were on (it shouldn’t be able to energize if you can access it) you shouldn’t be able to touch any of the HV conductors. I’ll let who ever have the last word on this, I’m tired now. - Rich