Pricing based on machine runtime

bardiir · 2017-06-09T07:27:04.000Z

I’ve looked through the suggestions for improvements and features yesterday and I’ve seen this request. While I feel like it would be a great addition to have a complexity modifier or runtime as a pricing variable I’m already doing this and thought I’ll just share my pricing setup as an idea for everyone who wants to include complexity into their prices.

Basically what makes an FDM printer slow is the perimeters. The more details you got the more perimeters you have.

So my basic idea was. The more details there are the higher the surface area is. I put the raw material cost into the ccm pricing and then added a cost calculation point for surface area, quite highly priced, uploaded a cube and tuned that price to my target for a low complexity object. Then uploaded a model of just thin walls and checked if the cost is where it should be. If the complex part was too highly priced I would shift some cost from surface to ccm for the cube baseline and if it was too low I would shift from ccm to surface

Then it was just a matter of relative pricing. If the filament was priced differently duplicate and correct ccm of the print speed was different for example flexible filament duplicate and adjust surface cost.

Prefect prices every time now. Adjusting the surface area this way and having a little overshoot also calculates quite nicely into support material cost.

bardiir · 2017-06-09T08:05:39.000Z

-> This is a point where 3DHubs could really improve a lot, offering you your own model uploads for pricing calculations/estimates in the preview not just different sized Marvin.

edservices · 2017-06-10T01:49:24.000Z

Really like the idea of uploading own models to estimate/preview pricing instead of Marvin method.

I had this issue before where a relatively complex part taking ages to print but quoted cheaply due to sliced volume pricing model. Later adjusted the sliced volume price but ended up simple part costing too much! Really appreciate your suggestion to add surface area costing method, will give it a go.

Odense3DPrint · 2017-06-10T19:15:44.000Z

i will give that a go also when i bring my hub back online after machine upgrade

a screenshot could have been nice

Odense3DPrint · 2017-06-11T07:15:09.000Z

it was easy enough to set up.

i used a combo of surface area and objecct volume. The latter because it makes it dead easy to set filament price… sliced volume is an object with only 25% infill. So going for 100% infill makes it more easy, just calculate the raw filament cost and enter it

Odense3DPrint · 2017-06-11T07:33:08.000Z

hmm…

i choosed one of those hairy models as the complex one and got the price where it would say it was ok

then i picked a 10cm marvin as the simple model… now the price is way off

there is an hour in difference for the print time according to cura engine in repetier host. but the price at 3d hubs is 50% lower

so what could be done wrong on my part?

Odense3DPrint · 2017-06-11T07:36:49.000Z

to make it more strange the 2.5cm marvin is ok priced

Odense3DPrint · 2017-06-11T07:49:04.000Z

used this one as the complex: Rocktopus 2 ( 2 hands and hair ) by joeostrander - Thingiverse

it takes about 6½ hours to print and the price on github reflects that ok

then i took the 10cm marvin as used in the preview… its a hughe one and takes about an hour less… its a simple one with not so much surface, but it still takes time to print, pricing is screwed on that one

but if i take the standard marvin it hits the price ok again

is there anything that can be done about this? so close to perfect prices and still not at the finish line

bardiir · 2017-06-11T07:59:59.000Z

Simple part too cheap -> Set ccm higher, Surface lower

Simple part too expensive -> Set ccm lower, Surface higher

bardiir · 2017-06-11T08:04:57.000Z

I would count small marvin as complex, there is very little infill compared to the shells. So you have set the surface price too high and need to set higher ccm and instead lower the surface a bit. On the other Hand I would not select something like Hairy prints or other stuff that has some “special” properties as a base pricing. You’re more likely to encouter someone without a 3D Printer beeing interested in this: https://www.thingiverse.com/thing:2230899 rather than a hairy print which is sort of a 3D printer novelty and mostly interesting to people who deeply know the limitations and thus think the hairy stuff is cool

Odense3DPrint · 2017-06-11T08:28:14.000Z

hehe

i just picked the first thing on thingiverse that would have a lot of surface area

will give deathwing a try

so you would recommend using deathwing as the “complex” and then a simple cube as the “simple” model to set prices?

Odense3DPrint · 2017-06-11T08:29:15.000Z

btw. did you use sliced volume or object volume ?

bardiir · 2017-06-11T08:49:36.000Z

sliced volume, but actually, thinking about it object volume might make more sense as it doesn’t involve the perimeters. In the end using sliced volume and surface does count the perimeters double. And what you’re doing with using object volume and surface area is sort of replicating the sliced volume but with your custom weighting for material/complexity.

edservices · 2017-06-11T08:49:45.000Z

I am really very very shocked! Is this hairy thing really printable with FDM printers?seriously? Most likely I’ll reject such job if ever come across it, very low confident to deliver.

bardiir · 2017-06-11T08:50:42.000Z

Well Deathwing is as complex as it gets for me, lots of support, very fine details, lots of it. And a cube is as low as it gets so i guess these are nice extremes yes. Everything else like hairy prints or other special stuff would be stuff to discuss with the customer directly.

Odense3DPrint · 2017-06-11T09:05:02.000Z

i picked object volume since the explanation for it says that its 100% infill and that is what my raw price is once i have converted from kg to cm3 and figured the price

i assume that 3d hubs does some internal calculation to figure out how much material is used and then calculating the cost based on that

i tried to slice deatwing in repetier at 0.1 layer heigth, it looks like a dragon with the wing skin taken off

http://imgur.com/a/cCL29

any special settings to use to make the skin show up?

bardiir · 2017-06-11T09:07:43.000Z

Yeah it’s totally easy but it does screw up pricing a lot because the support is rarther special for that. Basically what it boils down to is a print where there are hairs standing out and you comb it into shape with a hair dryer to soften the plastic stands up again, this is a special technique in handling a special support structure, it’s not printed like it looks directly.

bardiir · 2017-06-11T09:18:37.000Z

The skin on the wings is veeery thin. Your slicer is probably ignoring it due to the minimal wall thickness. You can choose something different with a lot of wallt too of course, on the other hand, even without wings deathwing is quite complex, just not printable in that case

Slic3r kind of has a hard time with it too, Simplify3D does handle it better if you choose very thin layers.

Odense3DPrint · 2017-06-11T09:38:05.000Z

for the purpose of prices i can set it as thin as needed to make the skin work

can you tell me how thin walls would be needed to make it work?

what i do here is to compare the time in my slicer with the final price in 3d hubs to check that i have set the price for surface right

bardiir · 2017-06-11T10:21:17.000Z

I’d advise you not to do that, because that would make print times unrealistically high. Be honest, you wouldn’t accept deathwing to be printed on the hub, would you? You should choose the most complex objekt you could think of that you would accept as an order, otherwise you’re skewing the scale potentially a lot.

25µm Layers will do the trick for me with my 0.125mm Nozzle size.