Higher Support Material Resolution

[ollienor]

One of the types of prints I have been asked to do most frequently are models of fairly large complex molecular structures, these typically consist of hundreds of approximately 2-3mm in diameter and around 10mm in length stems which link together (often in very random directions) to form the molecular structure.

When printing these they obviously require a heck of a lot of support material and inevitably result in multiple areas where the print partially fails. The support material can sometimes take around 4 hours to remove, I meticulously pick at it with wire cutters, tweezers and a scalpel.

One of the main reasons that the prints partially fail is because the support material resolution is not fine enough. I set it to 1mm; imagine a 3mm diameter stem, 10mm long with a full radius at either end standing vertically (standing up on the radiused end); I appreciate this is a challenging print for any printer/slicer. What I need the slicer to do is to calculate support material throughout the radius and print a kind of basket around it, fully supporting it but with a maximum resolution of 1mm what I end up with is is a tiny little 1mm square pad that the radius sits on, which inevitably gets knocked off on the 2nd or 3rd layer.

So far, the only printer slicer I have ever managed a full, successful print of these structures is the Up plus 2 printer with its own software which automatically calculates support material to a higher resolution than S3D will allow.

I believe all of my problems could be solved by allowing even 0.5mm resolution for support material calculations and I certainly believe this should be very simple to implement?

[brian442]

Seems like a better solution would be to just use the support extra expansion distance. Set that to 1-2mm and it will create a larger basket like you described to support everything. That's going to work much better too since it will give the supports a wider base so they don't fall over as easily.

[ollienor]

I appreciate the reply and understand what you are saying.

Unfortunately this is not adequate, the support "basket" printed at 1mm resolution still does not make contact with the model frequently enough for it to function. The "basket" formed by the Up slicer software follows the contours of the model very closely, the "basket" formed by S3D at it's highest resolution is more stepped, with the spacing between each step far too course to be of any use.

As I said before, It would be solved completely if supports were calculated with a higher resolution. I understand this would increase the calculations involved and take more time to calculate and also longer to print but sometimes that's what is required.

[shocksofmighty]

I print complex molecular structures (ball-and-stick) as well. There are limitations to what you can do, and the problem is more that you need so much support material to begin with. You are much better off generating your models in a way that avoids supports as much as possible. I wrote a series of blender scripts that creates a 'pinned' model, so you can print things off separately and stick them together afterward. This significantly cuts down on the need for supports. Here is a ~72,000 MW tRNA:

http://www.thingiverse.com/thing:1937646