Form1 Linearity Calibration Procedure Available?


#1

Good day,

my current tests let me think that my printer has some kind of mis-calibration on one axis (peel axis).

Is there a calibration process available?

My test model is relatively simple, but 0.5mm difference on the cylinder dimension is definitely too large…

That a very good exemple where a good resolution does not equate to a good accuracy!

More pictures and measures on my blog: http://wp.me/p3gI7M-8z

Cheers

[Edit: I’ve opened a bug #2102, and will keep updating this thread]


Retro Form 1+ Guide
#2

Though luck for anyone thinking about using the Form1 for anything serious for mechanical assembly, there is currently no way to compensate for this for the moment…

Here is Formlabs answer to my open request:

Hi Damien,

thanks for bringing this to our attention. We appreciate you keeping an eye on this, so please let us know if anything changes (for better or worse). Right now this is not something you can directly tweak but we plan to develop something along those lines. We’ll let you know as that develops. We appreciate your patience as we handle this remote diagnosis and again thank you for documenting this, it’s extremely helpful.

Thanks, Jennifer

Hopefully the situation will change soon…

Cheers


#3

I have a similar issue on a larger scale now.  The funny thing is though that I got about 50 hours of print time without any issues and now I have a major skew in my x axis. See my post here for pics.  Hope I can get it fixed soon or that they release a calibration procedure/firmware reset

http://support.formlabs.com/entries/24795748-Printer-X-Calibration-Gone-Bad


#4

I have build a calibration procedure for the Form1 (http://wp.me/p3gI7M-9d).

Using this method I know that my printer has a **1.4% error in X axis and 0.35% error in Y. **

The laser spot diameter is also off by 0.2 mm.

I would be interested to know if anyone could do the test on their printer and report the results!

We have no way to enter the parameters in PreForm for the moment, but hopefully Formlabs will give us this option in a coming version…

Cheers


#5

Bump - Formlabs are you able to share a calibration procedure?


#6

Josh, the calibration procedures, at this point, are something that can only take in our facilities using specialized equipment. We’re working on tackling this issue head-on, by rolling out new software and firmware updates, as well as taking a look at the mechanics and controls of the underlying components.


#7

I’ll pile on here since I have a similar issue, though not quite as bad as Damien’s-- I have about +0.7% on one axis.  It’s constant and predictable and just enough to add up to significant amounts on larger prints.  It’s not a show-stopper for ‘art’ type stuff (many wouldn’t even notice it), but for ‘engineering’ (eg, prototype product enclosures/shells) it’s a problem and prevents mixing and matching Form1 prints with other parts from Shapeways, etc.

In my case I’m 99% sure I could fix it with a fraction of a turn on the y-axis gain of the galvo amp, but we’ll wait until the warranty is up for that. :wink:  An option in PreFrom to essentially apply a ‘distortion’ to the geometry when it goes to the printer would probably ‘fix’ me in a much more user-friendly manner.


#8

I think this is the same problem I have.

Lately it has gone so bad I can no longer use the printer for anything but perhaps abstract art.

The walls in the picture are supposed to be right angles…


#9

Will, unfortunately, what you’re showing there is much more dramatic than a calibration issue! There’s something amiss with one of galvonometers in your Form 1 that controls the position of the laser beam. Our support team will help you out soon!


#10

I’ll jump in too.

I’ve been in contact with support and they’ve told me there’s nothing they can do to help me - effectively I can sit and spin. They say they’re working on it. I don’t believe what they say anymore.

I have a trapezoidal skew where all three axes are out and a 1" printed cube measures 0.970", 0.980", and 0.990". Assuming you measure the widest part on each axis. The parts are trapezoidal on the top plane though, and are undersized more toward the back of the printer than towards the front. I get ellipses for circles and essentially, all I can make are pretty deformed baubles, maybe, which makes my machine useless for anything I need to do. My parts don’t come out square and are way out of tolerance. Essentially, I have a piece of junk - a very pretty and very expensive piece of junk.