Laser Finances...or how to replace $30-40K worth of lasers every 2yrs


#21

People still manage to destroy those other tools as well even with a proficiency test.


#22

Based on the research I’ve done the higher cost translates to higher performance (faster movement, better accuracy) and longevity like radio tubes instead of high voltage tubes. These are great features for businesses where a handful of highly experienced people will be using the machine for many years. Productivity is increased and if taken care of components will last a long time. This doesn’t really represent the use case of the makerspace though.

High cost doesn’t necessarily translate to better handling of abuse. As @kbraby pointed out, cutting something with chlorine will trash a $75,000 machine just as quick as a $7,500 machine. The machines we’re using now represent good value and they’re not so expensive that mistakes can’t be made. If someone breaks a $20 lens it’s annoying but it’s not something worth raking people over the coals for. If someone breaks a $500 lens it’s different.

A higher end laser could be worth it but we’d need to figure out how to handle accidents and such ahead of time. For example a $5,000 deposit? Sounds crazy, I know, but so is buying a $75,000 laser for a thousand amateurs to use unsupervised.


#23

You raise interesting points.

If misuse is the leading cause of damage, then higher cost lasers wouldn’t improve that. It would seem that buying higher cost lasers would also translate to higher cost usage fees (in order to amortize the inevitable replacement costs).

It sounds like we need equipment that is robust to “heavy” (but not incorrect) usage; while not buying lasers that will cost us a bundle if they are trashed through misuse.


#24

We really shouldn’t consider the lenses to be as big of an issue as we are thinking. The lenses are cheap and a consumable item. They can get dirty for many reasons, not just misuse of the machine. Also, as use of the machine goes up we should expect more often failure of lenses. This seems obvious to me.

Why do we have to buy new machines instead of changing the laser tube and optics? I get Donner took a major hit, but have the other two machines been damaged to the point that they need the gantry replaced as well?

These are pretty simple machines and don’t have a ton of things that fail.


#25

My observations have been that Laser users are not causing catastrophic asset damage incidents . From what I have seen over the past year, it’s been a combination of intensive usage paired with beginner level mistakes that impact lenses, the bed, the gantry, the software, etc.


#26

Here are some things I’ve seen on the lasers at DMS. Martials bolted to the fragile honeycomb grid, turning the compressed air off and forgetting about it, cutting imitation leather fabric (contains chlorine), using sledge hammers to hold martial which the head slamed into, cleaning mirrors with dry paper towels, impromptu mirror adjustments without training or understanding of their adjustments, the list goes on. Having a more expensive machine wouldn’t change any of these things. It’s people being dumb, forgetful, and careless. I’m guilty of being dumb, forgetful, and careless at times, I think just about everyone is now and then. Now multiply that by a thousand.


#27

Someone correct me if I am wrong, but I have the impression the mechanicals are wearing out, causing problems with slop and misalignment.


#28

but what does that mean?

belts, pulleys, carriage bearings are all cheap and replaceable.

if you really think an 8k machine is being rendered worthless after 2 years of usage, I’ll be happy to take it off your hands.


#29

Challenge is that Epilog or Boss Laser lenses are not $20. I mean you can get Chinese lenses for $20 for these lasers but then you void your warranty.

Until we have skilled users who care about DMS equipment, spending 5-10x on equipment is not an investment in improved uptime or longevity.


#30

The assumption is that a $20 lens in a $20 lens-accepting laser is just as easy to break as a $200 lens in a $200 lens-accepting laser. I don’t believe that’s the case.

Here’s one a lot more people have experience with. Hand someone who doesn’t know what they’re doing a drill. They’ll probably break a Harbor Freight drill quickly, but they’ll have a hard time breaking the DeWalt one.

Now, wether that means it’s worth it to hand out the DeWalt drill depends a lot on the situation, but it’s not fair to assume that the DeWalt will fail at the same rate as the Harbor Frieght.


#31

I mean you can get Chinese lenses for $20 for these lasers but then you void your warranty.

Do you really? How could they possibly know, the lenses are swappable.

What does void your warranty is cutting any chlorine containing material…


#32

Having seen cheap lenses cause back reflections and destroy equipment far worse than corrosion on the gantry, don’t skimp out on the optics on a laser designed to make precision fires.


#33

1800 hours of use over 3 years averages out to 1.64 hours per day; I don’t know the duty cycle on our lasers but I imagine it’s markedly higher. Can’t speak to operator skill in a uni makerspace vs DMS, but I suspect that at a minimum respect for the equipment was greater at your uni simply because of a smaller userbase.

Are we getting half an order of magnitude more operating life out of it? Will the added CAPEX have some offsetting effect on the steady OPEX of our existing lasers?

Are we talking HF vs DeWalt durability or is it more like Ryobi vs DeWalt? It’s a critical distinction.


#34

I would like to hear more about the special features the higher-dollar lasers have that protect the optics and motion control from stuff like fumes from cutting PVC or whatever generated the sticky soot a few months ago.


#35

High end machines have compressed air blowing on mirrors as well as the lens so the mirrors stay cleaner longer. This doesn’t help if someone intentionally turns off the air to cut paper and leaves it in that state. There are definitely features in high end lasers that we could benefit from but I don’t think they’re a good investment given our use case.


#36

Can we install something like that on ours?


#37

Yes absolutely it can be done.


#38

I have my own laser cutter so not a lot of skin in the game at this point.

Higher quality laser cutters tend to have much better optics but they are smaller ~12-14mm instead of ~20-22mm. Also they tend to be rated for much higher powers. I think Epilog rates theirs fro 500watts which seems crazy when most of their machines are under 200watts. May be the peak pulse mode that requires it. I will ask at the Lewisville Library about their maintenance issues.


#39

I’ve suggested it at a recent committee meeting, people were afraid the extra weight might cause missed steps in the gantry. I’m all for it (and while I understand the concern, I think it’s worth trying out), if nothing else but as an interim solution before a higher quality machine :wink:

For the analogy, it’s hard to justify what quality we’re talking about without hard data, but I believe we’re talking HF vs DeWalt.

In addition to the air blast on mirrors, the fume extraction is much stronger on higher end machines. Cutting a smoky material, you could watch the smoke stream back into the exhaust plenum before it was able to rise to the height of the gantry, and a full bed sheet would be sucked into the cutting table by the exhaust fan.


#40

Stronger exhaust fans are an easy fix. This does not need to be part of the laser itself.