You are not logged in.

#1 2017-06-07 15:56:53

macdarren
Member
Registered: 2017-03-20
Posts: 115

New infill Cap idea...

Had this come up today....

A larger model that didn't need much internal structure thus had a wide spaced infill pattern.

But I wanted it to look good and generally be closed...but didn't want to capture a great deal of resin.

So I was thinking if the cap layers (in my case the last layers being printed) could have had smaller holes instead of no holes (current implementation) or open infill (as I mentioned in another post)
if it could have a smaller drain holes pattern centered on the infill...this would mostly close off the cap but leave places for resin to drain.

I think it could be accomplished by setting a min drain hole parameter and then over the course of the cap layers tapering or just changing from the infill grid size to the min drain hole size.

Really cool would be a harder but nicer finishing step that would find the Lowest point and place a drain hole there then under the cap layers create a gap (rather open like horizontal infill or just
infill columns that don't quite reach the cap layer on all six sides) that allows resin to drain from other infill columns to the low point and out the drain hole.  This would allow a hollowed out model
with very few drain holes that still seems generally solid.

Issues would be with models that have the last layers with fine details or very uneven stepped last layers and figuring out where to place the drain holes...maybe the in supports layout there could be a method for
drilling holes at the various low points (easy to see with in that view with the slicing plate feature already there) and the user could then choose were to put the holes....assuming the interior would have
a gap on the other side of the cap layer as mentioned above.

I know this is may be not a high priority for most users but thought I would toss it out as a future feature

Thanks for all the effort that has already gone into NANODLP!!!

Offline

#2 2017-06-07 18:57:16

Shahin
Administrator
Registered: 2016-02-17
Posts: 1,834

Re: New infill Cap idea...

Good idea. But if your main concern is waste of resin. As another user mentioned before, lifting to outside of resin level will cause the most of resin go out of structure.
For direct control jump layer could be used and for RAMPS G1 Z{1+([[LayerNumber]]%10==0)*5}, so you would not effect print time much.

Offline

#3 2017-06-07 20:13:42

macdarren
Member
Registered: 2017-03-20
Posts: 115

Re: New infill Cap idea...

Thanks for the feedback, I am not sure how the lifting idea helps....If you plunge a model with an open cylinder (as created by infill) into a vat full of resin then expose it such that the tube is closed off by the current layer then the tube will be filled to the level of the resin in the vat...yes if it is thick resin or the vat level is low it might be less than full before the cap layer seals if off.

Because my printer doesn't yet have an auto resin level system I tend to want to fill the vat fairly high to prevent running low on resin and having gaps or incomplete prints.

I already actually lift my models quite high to allow fresh resin to mix in as this seems to help prevent over exposure on thin gaps near heavy exposures.  I do this in conjunction with dimming which also helps with this same issue.  Maybe I will try the formula you gave and see how things turn out I might be totally wrong on what is happening....I admit I haven't looked at the whole formula power of nanoDLP so could be I am not using the tool at it's full potential.  I am not sure what this formula does or how to read it.....seems like it is trying to lift more based on Layer number?


The model where this came up was a big boxed cylinder type thing...so basically while it was mostly hollow with wide open infill, the last 15 mm of the cylinder ended up with resin trapped in the bottom as it was sealed off by the cap...now not normally a big problem (I could normally rotate the object while post curing to distribute the resin on the inside) however the resin sorta gelled in the bottom making the part heavy at that end once cured....which as it turned out was the near the top of the part making it kinda top and side heavy though it looked ok...printing it inverted would be the obvious solution but would probably have required more support structure and post finishing to hide the support points as they would have now been more obvious.

Again this is probably a future refinement not a must have feature...there are ways to minimize this with pre hollowed objects with include drain points etc....I just prefer to keep my models separated from the printing/casting/milling process such that the model can be used anywhere but is then processed for the specific production environment.

Offline

#4 2017-06-07 21:14:57

Shahin
Administrator
Registered: 2016-02-17
Posts: 1,834

Re: New infill Cap idea...

Yes, move 6mm for a layer and 1mm for other 9 layers.

Offline

Board footer

Powered by FluxBB