Surface issues with close packing

The main purpose for our printer is to create ‘3D business cards’. We are in the metal stamping industry, so that means all the parts are replicas of formed sheet metal parts. This is a large scale electrical box terminal:

The walls are about .075" (~2mm), with many areas being thinner for recessed lettering and other stamped details. Overal the part is roughly 3"x1"x1".

If i print one all by itself, (or even with another item or 2) i get great results:

Problem is, I need a dozen or more of them per week, so I need to fit a bunch in at once:

But when I print many of them close together, the surface quality turns to rubbish:

The worst of the texturing is always facing the front of the printer, with the parts on the peel side being worse than those on the hinge. The individuals pieces that turned out well were printed using the exact same supports. I have used multiple (new) trays and fresh resin, but those prints do not differ much from those on trays that have a a liter or more though them. The only difference I can come up with is the large amount of surface area involved with printing 9 of them at a time compared to fitting one or 2 of them on with another large part.
Anyone have any ideas?

Link to .form file:

well, since that 6 hours was wasted, try printing just 3 next. overall you’ll save time.

probably not the answer you wanted. also, with less, and on thier side, it’ll take way less time - maybe a third of the time. For instance, I would print that part in the orientation of your second photo (crimp tangs pointing to PDMS), with the crimp tangs at the hinge side, box end toward the peel side using 1.3 density @ .40 point size.

heh, actually, now seeing what you’re really doing, making a bunch of the same thing, you really should be using resin and silicone molds. when you’re only tool is a hammer…

Then, you can do one, post finish it really really good, and make the mold from that. time spent up front will same boatloads afterward.

Heh. It sounds and looks like it’s related to the flare problems people where having. Possibly with that many items packed together the combined exposure from the flare results in over curing and curing of material that was not supposed to be cured. If it is then don’t hold your breath that anything can or will be done about it.

The theory behind going with a 3D printer rather than a silicon mold is that we can personalize each part… things like customizing the web address to point at a product most relevant to the customer. But unfortunately, that never came to fruition, and we have just been printing 2 or 3 different versions with slightly different messages. Frankly, I think my boss just really wanted a 3D printer, and I’m not complaining! :heart_eyes:

But, even if we are not currently taking full advantage of the machine, I would like to figure out how to printer a large number of slightly different parts like this. I am working on setting some up laying down:

Do you think I should be rotating this over to a high angle? Leaving it flatter allows me to keep all the supports on the bottom face for easier post processing.

I hope its not the flare issue. I poked around with trying to get pictures of the laser spot, but clearly my camera was never intended to take pictures of lasers! :stuck_out_tongue_closed_eyes: Maybe it is worth trying to borrow a better (or at least different) camera.

Check out my DSLR laser spot dissection thread here for information on getting usable laser spot pics. Just a normal single picture is not enough with any camera. The more interesting thing here is you have not had laser flare issues so far so you likely don’t have a particularly bad spot. IF this is a laser flare problem it is a likely a different manifestation of the problem caused by lots of closely packed items and supports. I would be interested how this print prints on other Form1+ printers, to see how common the problem is. It could explain some other artifacts that happen under certain circumstances.

I wouldn’t think molding this part would be very easy… Certainly wouldn’t be doable with a 2-part mold.
As far as the trouble with printing many parts at once, I don’t think you’re alone in that issue. I haven’t tried nesting too much, but I think of those who have, more have had troubles than haven’t. I think it’s just a limitation of this printer, though I don’t know why.

Often times the problem with packing is due to excessive adhesion from to much surface area, which results in striation. This case is different though, it looks more like inconsistent over-curing than striation, focused primarily on one face with the problem being worse on the peel side, all of which is consistent with flare.

I managed to take these two pictures with my point and shoot. Unfortunately, this camera does not have ISO or shutter speed settings, so I cannot get much better than this.

I tried taking a picture with my Nexus 5, but it just could not handle this intense level of contrast. Is it worth my time to borrow a DSLR? As long as you could tell me what ISO/shutter settings to use, I could make it happen.

It won’t do much good at this point. This is not the same case as others where reporting. Have you printed the cross and helical walls. I thought you had already done the basic testing for flare and come out fine. So the minimal data that has been found and reported doesn’t really apply. The problem here is that currently you are the only case of someone noticing the problem only when packing groups of objects. I would guess there are others who would experience the same problems even though their printers are fine for single objects. I wish we could get a group of users to print the single and the packed group versions and see how different printers handled the problem and whether the bad faces correlated to the direction of the flare. Then we would have more solid information about how common it is and if it does have a connection to flare or not.

Would it be possible for you to post the two .form files somewhere?

Here is the link to the .form file for the 9-up terminals:

Which other file are you referring to? The attempt to print the terminals laying more horizontally did not work so well. There was issues with the sides bowing, as it is hard to support faces at that angle covered with text. I have another batch about to start of 4 terminals, in the same vertical orientation as the 9-up, but places more or less between where they have been printed.

The other one I was referring to was the .form file with only one terminal that printed successfully.

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