Calibrating the laser?


#10

I asked but so far, nope.


#11

Of course not!

Why would they want to loose such a cash cow?

When you need something fixed, they charge $800 for something that probably costs them $50-75 and an hour worth of labor to fix.

Or, better yet from their perspective, when the user can’t fix the unit or decides the cost of repairs is too much, they end up buying a $3500 Form2.

That’s why they are so uptight about parts or DIY repairs. Make no mistake, IT’S ALL ABOUT THE MONEY.


#12

I believe the laser used is <$300 and not much for labor for installing but probably time consuming adjusting the focus and collimating it.


#13

The laser diode, which is what we need to replace is about $7, not $300. Besides, we’re not replacing the entire laser assembly. That assembly contains the cylindrical/barrel case, a screw on collimating lens, and the laser diode which is soldered onto a Formlabs PCB shown above.

Those components, (the complete laser assembly) probably add up to about $20. The laser barrel and lens cost about $7-8 in small quantities, and the PCB, assorted resistors, diodes and transistor are less than $5.

As for the work of focusing the laser, it’s a simple matter of turning the front part of the barrel until the beam is focused to whatever specifications they need (distance & beam/dot size). That process should take less than 10 minutes.

The calibration process is a matter of determining the actual output of the laser. That can be done using some standalone testing equipment, or more likely it’s done by reading the laser’s own built in photo-diode (I did mention the laser TO18 package has a built in pho-diode). The output of the photo-diode can be read and the reference output can be adjusted accordingly.

I have a feeling that most of the diodes made by the same manufacturers have nearly identical outputs, and in general, replacing the laser diode and not touching anything else, should work. Whatever variances there are between diodes, are probably too small to have a real effect on the existing calibration.

But all this (the bit about calibration) is conjecture, so the only way to find out is to actually try it. My printer is currently working fine, so I’m not going to try anything until the laser goes out. But once it does, and it eventually will, I will do the diode swap and report the results.

A bit of a theoretical info on the FormLabs PCB (or how I think it works):
The laser output degrades over time. As such, it requires more power to deliver the same output level. It’s for this reason, the laser diode package also contains a photo diode, which reads the laser output in real time.

This is where the FormLabs PCB comes into play. It does double duty, it provides regulated power to the laser, while at the same time, it reads the output of the photo diode, which it sends to the main logic board. The logic board checks that output against the original reference reading which was obtained at the time of the calibration, and increase (or decreases) the power to the laser in order to match the original reference output.

Over time, the input voltage necessary to drive the laser’s output to the desired level, exceeds the safety margins, at which time, the laser simply can’t output enough power to do it’s job as it originally could, so it requires replacement.


#14

The diode should last way more than 10,000 hours. As far as the laser degrading over time I don’t know if there is a gradual fall off or if fails rapidly at the end of life. That particular laster has the lens built in on the F1+ and I believe it is a fixed focus so for fine tuning I think it is just a matter of shifting it forward and back within the mount? The laser with lens I saw as printer parts from China were $299 and has a connector that goes to the board. It doesn’t look like it is soldered on. Maybe the earlier models they were?

There shouldn’t be much fine tuning when replacing that type of laser unless there are drastic differences in quality. Perhaps that can be done in OpenFL with a few print tests?


#15

That’s marketing specs, not real world specs. While a laser may output a light for 10K hours, it will not be doing it at full power. There are a few white papers that you can download that show the life expectancy of lasers, including Blue/violet lasers.

One study shows that a 120mW violet (405nm) laser, driven at 50% duty cycle (1/2 the rated power output), will degrade gradually with use, and by the time it reaches about 8000-9000 hours, it’s output will have diminished below 40% of the original rating.

Also, as the laser ages, in order to maintain a certain output level, the electrical current that drives it must be increased, which leads to faster degradation yet.

So as you can see the 10K hours spec is not accurate at all. I’m sure someone can come up with a equation that would tell us the average useful life expectancy of these lasers, but I think the number is more like 1000-1500 hours or less.


#16

According to my exported stats from the dashboard, my Form 2 has printed for about 1900 hours and still appears to be working fine. (The laser is probably only in use for 30% of the print time, given the peel and refill operations… still, there have to be quite a few users who are well beyond my usage.)


#17

My informations differ : at least for some hardware (still speaking about 400-500nm-ish LDs) the ageing is less pronounced if the LDs are driven at their nominal current rather than lower. We also have marginally but still noticeably less pessimistic output values after prolonged usage. The way the LDs are driven and last but certainly not least the cooling are important factors as well (these things don’t like to get hot).

I agree that after 10k hours the laser will not be able to output 100% of its nominal rated power, but 1000-1500 hours or less of useful lifetime is just not a realistic thing to say.


#18

Not sure how accurate this article is but seems the diodes will run consistent for at least 30% of their life before you need to increase voltage.
http://www.radio-electronics.com/info/data/semicond/laser_diode/lifetime-failure-reliability.php

So 2000-3000 hours?


#19

Whatever the lifetime of the laser might be. I print the same models always and about some years now with the same orientation and support structures - but every time I got a software or firmware update I had to change some things. Like rescaling them and add thicker supports to them and so on. Its like the software-updates change how much power output the laser is working with. Working with a form1+ gets you grey hairs while fighting the bad print symptoms but not solving the main problems - so why should I invest so much money in formlabs anymore??? makes no sense to me so I will give competitors a chance in the future.


#20

FL does tweak the exposures for the materials and constantly improve the support structure system. In a couple of cases the newer exposures didn’t work as well for my and I ended up reverting back to an older version. I pretty much only use the OpenFL now so unless a particular resin is discontinued I have no reason to change. Still have my F1+ and it is serving me well. I like the simplicity and freedom of the F1+. Even though the optics are exposed, keeping a cover on the machine when not in use solves that.


Aftermarket Form 1+ Laser Replacement
#21

I had the same issues with my laser degrading.

Today after painfully removing all the resin formlabs put in the laser to prohibit opening, I (carefully) disassembled my form1+ Laser.
I found out it’s not containing the TO18 Laser everybody is talking about. But a much smaller TO38 Laser.

On aliexpress I bought a pair of spare lasers from Sony and Nichia.
They will arrive within a couple of weeks.

Hopefully they work right of the shelf, otherwise I will investigate how to calibrate the lasers.
Did anybody ever attempt this? or care to help if needed?


#22

Unless I am mistaken, no one has been able to calibrate the laser or galvo’s besides Formlabs. One would need special tools and the software to go along with them.

If you figure out how to do this I gather many will want to know what you did.


#23

Interesting. Is your printer a Form 1, 1+ or a 2? Also, do you know roughly when it was made?

My laser comes with a black housing, and it doesn’t have any epoxy or resin or hot glue, I can simply unscrew it. And it does have a TO18 diode.

The TO38 housing is just smaller than the TO18, but the laser specs are what matter.


#24

I have a form1+ I believe its from 2013.
I ordered some to38 lasers with same specs as the to18
The pcb seems to be the same.


#25

Hmmm. I’ve had 2 Form 1+ printer, which I bought used. The first one I bought in 2016, and it appeared to have been a Form 1, that had been updated to Form 1+. It had the black housing laser. I never opened the laser so I don’t know what type of diode it had.

The current one, I bought used last year around April or May, and according to the previous owner, it was just about a year old at the time, so it was made in 2016. This is the one I opened the laser housing on, and it has a TO18 in it.

I wonder if FormLabs has more than one vendor for the laser, and they use them interchangeably?


#26

Did anyone have any luck?
Mine looks like it’s the sealed version of the laser


#27

Hello good afternoon.

I have a Form 1+ for garbage.

To know my horrible case you can see it here:

My laser is sealed. For business reasons I had to buy !!! urgently!!! a Form2.

So now I have my old Form1 unused because of my laser.

Please regardless of having purchased a Form2. If there is a compatible laser or a possible solution, please comment on this post.

It hurts me to have such an expensive equipment unusable because of just € 300, but of course these lasers are no longer manufactured.

Regardless of having purchased Form2, I am not happy with Formlabs, they have forced me through my uncomfortable situation.

It was problems after problems or paying a Form2 so that my company would not be more damaged.

I trust that someone or some company will look for solutions to these machines and be able to repair my laser or replace it.

Thank you


#28

I will have to open my form 1+ and change my laser so could you help in case of you have make some pictures and or movie
And where did you buy your laser ?
after changing did you have some problems for calibration did you need to do ?
thanks


#29

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