1

Is it just me, or does everyone else have to constantly apologize to customers when they send in an order for a part and I have to end up nearly doubling the bill just by checking the correct volume? The system seems to constantly give between 20% and 50% less for the volume, despite giving accurate dimensions. - And it even says the system is calibrated to assume a 20% infill etc, the exact settings I use to check a part in S3D.

So far all my customers have understood this and don’t blame me, but it will be hard to keep those 5 star reviews coming in, if this continues for long. And I can’t very well go out and make a 6 hour print for 8€ just to please a customer, nor can I hike up my prices, as I’ll lose my ranking. - I took a lot of time going over data to get to the price points I have specified, and would really like the system to be able to give the correct information, since it’s just math after all.

2

I hate to say this, but are you sure your math is correct? I’m printing right now, and Simplify3D reckons it’s going to use 614.4cm of filament. Assuming the filament is a cylinder 614.4cm long and the filament width is consistent, the volume used will be pi*r^2*h. I’m using 1.75mm filament so r in cm is 0.0875. Carrying out this calculation, I come to a total volume of 14.78cm3. (edit) OK the print has just finished and my machine reckons it actually used 617.2cm of filament, so working that out comes to 14.85cm3. 3DHubs has the order sliced as 15.4cm3, so Hubs is being generous, not underquoting.

Another order. Simplify3D says it’s 889.3cm of filament, which works out to 21.39cm3. 3DHubs has the order sliced at 21.7cm3, closer, but again slightly generous, not underquoting.

How are you calculating/seeing the sliced volume locally?

3

I am not looking at the used filament, but taking the calculation from the mesh on the first screen! The filament use calculation gives somewhat different results, which are valuable for certain things, but the price should be calculated by the volume calculated from the mesh.

4

Hi @Hoffa I’m not sure I understand what you mean by taking the calculation from the mesh. Regardless, surely the price should be based upon the filament you use shouldn’t it? Taking aside set-up, finishing, posting, etc. it’s the actual amount of filament you use that determines your cost in terms of materials.

In my case, what I’m physically using is very close to the sliced volume quoted by 3DHubs, and the slight error is in my favour so I see no problem.

What are you saying should be the basis of price, if not the actual amount of filament used?

5

Personally I’d be much more happy charging by the hour, as a lot of prints may be rather low on volume and high on time. At least the prints I make are rarely say 60cm^3 blocks done at 400 microns and done in under two hours. But that’s not a pricing option on this service, so what can I do. Pricing based on solely on filament use is the worst possible way to go, in my opinion, as the above mentioned block will weigh the same printed at 400 and 20 microns, but the 20 micron option will take 20 times longer to print! Sure I compensate by having a higher rate for 20 microns than I do for 100 and a higher one for 100 than 200 microns, since the system allows me that luxury. Filament is also really cheap, and is second only to the price of electricity in being the least important factor in running a 3D-printer. The price of the machine and maintenance, the cost of software licenses, the knowledge and manual labour of the operator… these are the things that the customer is also paying for, not just filament.

6

Just this morning I had a customer who wanted me to print out all the parts for a custom 3D printer. He made an order for 22 individual components that would take about 4 - 6 days to make, all in all (depending on how many parts I squeezed onto the bed at once) with very little printer downtime. The parts were calculated by the service to cost 160€ and when I checked the parts in S3D and looked at what needs support etc (only a few of the parts) I came back with a calculation of 325€ after my bulk discount. Obviously the customer wasn’t happy, but there is simply no way that I can justify printing for days on end and using nearly a full roll of filament for just 160€. …and out of that 325 the actual parts were 300 with my setup fee, support material and removal accounting for the 25…

7

I found that .obj files will give the correct (and nicely rounded up) values for the volume, but .stl files, which most of my customers use are the ones that are well off.

I guess those of you using mostly .obj files are the ones who haven’t noted this issue?