Simplify3D Extrusion Width Frustration

[Steve Gong]

I was excited to finally try out S3D after hearing so many people rave about it.  My experiences have been...frustrating.

The biggest thing that I can't get my head around is printing models that are small.  I understand that unlike Makerware, which is able to vary the extrusion width depending on your model, S3D requires you to have the entered extrusion width to be lower than the size of your model, if you want it to slice.  However, even with this understanding...

Say I want to print this thing - wall of model is 0.4mm thick.

I enter in 0.39mm as my extrusion width (since it won't slice with 0.4mm).  I print it and measure with a digital caliper, I get 0.64mm

Okay, so I try to enter in a lower value this time - 0.30mm, and then 0.20mm.  I print both out, and still get 0.64mm.  

Moreover, the path it chooses to take is not to go round each perimeter in one direction, but to reverse directions at the far right vertex.  So the four walls of this model are all different.

Printing this piece in Makerware gives me 0.44mm, which is pretty darn close given everything is on defaults.

I'll just start with this problem.  There are a lot of other things that puzzle me, such as prints that have spongy holes in them, prints where the seam where the z axis changes are not watertight, very odd stringing behavior, and just plain odd path approaches the extruder takes.

I really like the set of features in this app, but if I can't consistently get predictable and good quality prints, it doesn't really work out.  Why is Makerware the only slicer that seems to do variable extrusion width on a single print?

Thanks in advance.

[John B]

I agree it can be the most frustrating piece of software. When it works it produces quality prints like no other, but on thin wall it just goes nuts. I did question S3d about this and got a long reply basically they suggested, that say in your illustration above, you draw it as a cube and then tell it software not to print a base or top. Not a great solution.

[Steve Gong]

I'd be interested to read their response if you would share, as I'd really like to get further clarification on this.  Drawing as a cube and not printing a base or top is unacceptable.  Cubes aren't the only shapes that I'd want to print at specific wall thicknesses. 

Also, I noticed that when I'm printing, say, a business card with cutout letters on a "card", the space between two letters, an area of 0.9mm wide, and my extrusion width is 0.4, then essentially, there's a 0.1mm hole somewhere in the middle. Does this mean I have to always design models that are multiples of the extrusion width?  Because this would totally suck.

What are some success stories of amazing prints with S3D?  Maybe the software is better suited for certain prints, and given I bought it to prototype very small objects, maybe I'm wasting my time with S3D and should just stick to Makerware?

[Andrew Aurigema]

Are you printing with only a single perimeter strand ???  

What you want to do sounds like what happens every time the printer makes support material.  Those structures are single strand straight line builds that come out great and are free standing till they meet the primary part.   

On Thu, Dec 4, 2014 at 1:25 AM, Steve Gong <stev...@gmail.com> wrote:

I'd be interested to read their response if you would share, as I'd really like to get further clarification on this.  Drawing as a cube and not printing a base or top is unacceptable.  Cubes aren't the only shapes that I'd want to print at specific wall thicknesses. 

Also, I noticed that when I'm printing, say, a business card with cutout letters on a "card", the space between two letters, an area of 0.9mm wide, and my extrusion width is 0.4, then essentially, there's a 0.1mm hole somewhere in the middle. Does this mean I have to always design models that are multiples of the extrusion width?  Because this would totally suck.

What are some success stories of amazing prints with S3D?  Maybe the software is better suited for certain prints, and given I bought it to prototype very small objects, maybe Ishould just stick to Makerware?

On Thursday, December 4, 2014 1:06:48 AM UTC-5, Bruce wrote:

[John B]

I make a lot of small parts and tools with tight fits and I do design wall thickness and gaps to suit the width of the extrusion, maybe not the best way but they all fit and work well. I have forwarded the email from S3D as it would not cut and paste here. Hope it all comes through OK

On 4 December 2014 at 17:25, Steve Gong <stev...@gmail.com> wrote:

I'd be interested to read their response if you would share, as I'd really like to get further clarification on this.  Drawing as a cube and not printing a base or top is unacceptable.  Cubes aren't the only shapes that I'd want to print at specific wall thicknesses. 

Also, I noticed that when I'm printing, say, a business card with cutout letters on a "card", the space between two letters, an area of 0.9mm wide, and my extrusion width is 0.4, then essentially, there's a 0.1mm hole somewhere in the middle. Does this mean I have to always design models that are multiples of the extrusion width?  Because this would totally suck.

What are some success stories of amazing prints with S3D?  Maybe the software is better suited for certain prints, and given I bought it to prototype very small objects, maybe Ishould just stick to Makerware?

On Thursday, December 4, 2014 1:06:48 AM UTC-5, Bruce wrote:

[Steve Gong]

Yes, 1 perimeter/shell.  I notice that having 2 shells often screws things up as it'll leave holes all over the place.

[Scott Booker]

Out of curiosity... have you tried that same model with the "single outline corkscrew (vase mode)" setting?  That mode can make some pretty amazing prints if you have your heart set on single wall models.

[tramalot]

If you want to print 0.4mm walls you need at least a 0.35mm nozzle. the noodle needs to be squished to bond. then vase mode

ps, asking a slicer to extude thinner then the nozzel is asking for trouble

[Steve Gong]

I've tried to print the cute octo model with single outline corkscrew, and I don't know how to fill the top without it collapsing, since generally you'd expect the walls to thicken as it gets closer and closer to the "dome" in order to successfully close it.  I suppose I could increase the top layers to when the dome starts, but then I'd end up with a 100% infil top, which would clearly look unlike the rest of the print.  This still doesn't solve my problem however, if I want an infill.

[Steve Gong]

I've been doing this using makerware, and the prints seem to be fine.  If what you're saying is true, then is it advised against to print small parts that are at some places thinner than 0.4mm?  Frankly I think 0.4mm is quite thick.

[Ryan Carlyle]

Steve, to be blunt, you're using the wrong kind of 3d printer for the feature size scale you're looking for. If small features at tight tolerances are important to you, I would highly recommend switching to a DLP/SLA type printer. You'll be much, much happier with the results. 

FDM printers are very constrained by nozzle sizes, filament bead squash, overhangs, and other issues you're running into. For most practical purposes, the smallest size an FDM printer can reliably make is 2x the nozzle width -- except for specific operating modes like spiral vase prints. When you operate near the physical limits of the hardware, it shouldn't be surprising that different slicers have different ways of coping. Makerware happens to be one of the few slicers that is willing to violate general FDM printing "good practice" and extrude single-wall paths that are narrower than the nozzle. It also ignores the true oval cross-section of the extruded filament, so it's not bothered by trying to put a 0.4mm strand in a 0.4mm gap. (S3D compensates external perimeter placement for extrusion bead ovality, giving better fit on large parts, but as a side-effect causing issues on single-wall cross-sections like this.) 

For some people, Makerware's treatment of very small features makes it the best slicer. But it also has a lot of quirks, like the "empty gap in the middle" behavior that you've seen when the feature size is not a multiple of the extrusion width. You can play with the "internal spurs" width in Makerware to help with that behavior but it can cause some wonky output sometimes.

You might try Craftware -- it has similar general slicing behavior to Makerware, but will fill those internal gaps better.

[Bryon Miller]

I'd really like to know if anyone figures this out.  I print models constantly with .6 mm width walls and Makerbot makes them nice and thick.  S3D doesn't make them thick enough and they come out flimsy, I can't get this software to print certain types of models and it's always a problem with certain parts being too thin.

I'm amazed you can get .44mm width, I can't get .50 to work on my machine using makerware, the best I can get out of makerware is .60.

[TobyCWood]

Maybe there's a misunderstanding here on what the extrusion width setting actually is. It's not going to change the width out of the nozzle. It changes the width of the VIRTUAL extrusion. Use the preview. So lets say you have a wall that is .35mm thick in your CAD SW and you export it over as an STL and you leave the extrusion width setting in the process at .4mm... The slicer may not see the small extrusion width and will simply truncate or ignore the thin wall. If you set it lower to .35 it will see it but It will not print at .35mm it will extrude per your nozzle and filament diameter settings... but it will at least have the wall in the toolpath. It makes it possible to print things that you may not be able to without changing that setting. Can you actually print thinner then your nozzle with this? No.  Your nozzle is .4mm in diameter. You want it thicker? How can it do that after the first layer??? The First layer width and height settings we now have in v2.2 can make the extrusion out of the nozzle larger for a better stick... that's different then what I think you are talking about. It gets the thicker extrusion by having the bed to push the increased extrusion rate against and by raising the Z height a touch more. I can't see doing that above the 1st layer with an expectation of accuracy in the extruded tool path.

I suggest adding a shell.