Lonely useless supports


#1

Long slender isolated supports are utterly useless and should not be created, as they systematically fail to reach the point they are supposed to hold due to warping, viscous friction, and tons of other evident reasons.
It shouldn’t be too difficult to identify them and to add a support nearby so that at least a ladder is created which would have more chances to be of any use.


#2

Why didn’t you remove that point? Or better make sure there were a line of points along the exposed edge of the model?


#3

Hi Bill,
Speaking of point, I think that you missed it.


#4

Formlabs has to make a lot of assumptions when placing the supports. The automatic support generation is normally a good starting point but it’s not perfect. Why? Because we print a variety of complex shapes that Formlabs couldn’t possibly plan for.

I seldom if ever use the auto supports as is. It’s not like it takes more than a couple of minutes to add or remove obvious problem areas. I also accept that they won’t generate perfectly every time for every complex shape.

My point? This is a non-issue.


#5

We call those “noodles” internally. We’ve been working pretty hard at stopping the automatic support generation from creating noodles, but as you can see, it still comes up with some occasionally. They’re pretty stupid and annoying. As billb said, you should probably just remove them with manual support editing.

When you catch it doing something stupid like this, if you can share the FORM file with us, that can really help us chase down the remaining noodley cases. Often, getting good reproduction steps is ~80% of fixing things like this.


#6

The one I find most often is having two points very close together or even touching, but since I almost always use two point sizes on each print, checking and re-positioning points is just part of the expected work-flow.


#7

That’s the kind of reasoning that doesn’t push towards improvement…
What are you on this forum for anyways ?


#8

When Preform starts automatically using two sizes of support points, one for ‘structure’ and the other for ‘minima’ then I might be inclined to trust the point algorithm more. But I will still need to check, and override the point placement, if I thought they were wrong. Call it a need to take the same responsibility for the output as I would have if I was making the model by hand.

To be shocked by the whinging about first-world problems that I find here…


#9

How do you, personally, set the sizes for minima versus “structure”?


#10

Most of the models I produce are regular boxes with lots of detail added, so there is a fairly clear distinction between what is ‘structure’ and what is ‘detail’. So the workflow in Preform goes some thing like this:-

  1. Generate supports using 50% density, at the moment I’m using 0.4mm touchpoints for grey resin.
  2. Edit, and remove all the points where I know there is a lot of detail. Preform tends to overload details with lots of not very well placed points.
  3. Add more points until the model is more or less fully supported. These will usually be filling in gaps in the existing supports and will be on face which will not be visible on the finished model. However I have to pay particular attention to the edges that converge at the point nearest the build platform.
  4. Apply the supports to force Preform to show all the minima.
  5. If there are any obvious large minima then add 0.4 points to them otherwise place 0.2mm points on all the other minima. At this point the distinction between ‘structural’ and ‘detail’ point is somewhat fluid as a number of small points will have the same effect as one large one.
  6. Apply the supports again and repeat 5. & 6. until Preform indicates that the model is printable.

#12

I would think that Preform could be made to check how much a point intersects with the print and then adjust the point size to reach an optimized size.


#13

Hes here to troll people and make everyone feel stupid when they have anything remotely negative to say about the Formlabs ecosystem. God forbid anyone challenges a company who profits from its own engineering and design flaws.


#14

ROTFL

Love it when everyone wants their own version of “perfect”


#15

Bill,

as a rule, I don’t speak to grown men who still play with miniature trains.
Please go back to your tchoo-tchoos and ignore my threads from now on.


#16

Seeing as how their engineering and design flaws have resulted in them sending me 2 free tanks, 4 free cartridges of resin, and an entire whole free Form 2, I really don’t think you understand how their profits are affected by flaws.
It does them no good to have to replace cartridges that don’t read, and machines that don’t work, which they do.

They profit most when everyone LOVES their experience of the Form-2 enough to recommend it to others… When all those folks are merrily printing away- and regularly needing new resin and new tanks and new platforms and even additional printers to accommodate all the effortless printing they are able to do without nearly no issues.
and they ARE the ONLY printer maker out there in this price range even attempting to make a machine that you don’t have to fiddle with constantly just to get to work.
I point out that they have sold ten thousand of these machines or more- and yet we don’t see ten thousand users complaining about their flaws on this forum… so there must be a whopping lot of folks out there having a wonderful experience with the Form 2- ( although I suspect MOST of those silent users are folks who have had or run other brands of printers by which their Form 2s compare far more favorably )

It comes across as whinging when folks who buy a Form 2 complain about how Formlabs tries to make a profit. As if they should make a printer that earns them no money at all.

It comes across as whinging when folks expect or demand that SOMEONE ELSE figure out how to make everything work automatically so they don’t have to know anything or do anything to get perfect results every time.- especially so when they seem to think that making things easy for them is not that challenging a problem.

trying to get software to build a functional support structure that varies dramatically based upon the characteristics of the specific resin and orientation of a literally infinite number of possible shapes is NOT an easy problem to solve. The software does a reasonably good job of it… but trusting software to do it for you without having to double check yourself is why folks get killed in Tesla’s using autopilot.

And, of course, expecting Formlabs to solve these problems FOR you, while you whinge about how they dare to make a profit just makes you seem plain ungrateful.

The Form 2 is by no means a perfect printer.
Its just that its still twice as good as every other printer out there.
in my book, they deserve their profits.


#17

Thanks. Our goal is to make that unnecessary; it’s helpful to understand how you go about it.


#18

Thanks for the novel, but that’s no reason not to ask for improvements.
The algorithm here is rather simple :
IF “Lonely support” THEN :
IF “Lonely support Length”= small THEN ADD “one support nearby”
ELSE ADD “two supports nearby”


#19

It is not just about making sure all the minima have supports, there are also considerations about the ease of removing the supports without breaking the model. Losing a third of a batch of models because something breaks off is very frustrating. Having much smaller touch points has helped a lot, it means that many point will break off without needing to be cut.

There are a couple of things I’ve noticed that I have to think carefully about. One is clusters of points on different minima that are so close together that the supports fuse together making it necessary to cut them. Sometimes it is possible to put points on different faces so that the supports lead off in different direction, but not always. The other is that I find myself having to make decisions about which side of an edge the point should be placed. This could be for cosmetic reasons, or to give a better lead to the support or even to avoid a large internal support that lands on a delicate part.

I suspect that I am trying to push what is possible further than many people would, so I’ve put a file I have been working on here


#20

Maybe you should take up a modelling hobby. It will teach you patience, a whole lot of more or less useful skills and a reason to push the techniques you use to the very edge of what is possible.

Not mine, by the way.


#21

Thank you for the feedback. As we improve support generation, tricky models like those detailed bogies with many local minima are hugely helpful.