The waste is real but that’s ok

Lets talk about prototyping with (FDM) 3D printers, the inevitable failed prints, taking wrong measurements and all the tight tolerances.

Working on a recent project, a RC Willis Jeep, i had to do a lot of test prints. While the pile of plastic grew along the project, i had some ideas about this perceived “issue”. At first glance this might feels wasteful right? 

Immagine you are working on some sort of cover for a common gardening tool, to be printed on your printer. You take some measurements, throw it on your machine but discover that you are off some milimeters. The cover doesnt fit, but since it took 2h to print, you just take some sand paper and grind it down to the right size. 

This is an absolutelly rational thing to do but now immagine a second scenario. Although the cover does fit now, you saw some areas with thin walls during printing and areas where the cover might get leaky, if used outdoors. Basically build in failure points, only visible because having the “real object” aka the cover in your hands. You are going back to the drawing board and start the whole process one more time. The cover does fit now like a glove and is very robust. Awesome!
 

But not so fast. You are using the cover and also the device, it is designed to fit, for some time now. The design is snug, sure, but it feels clunky and also it just looks a little off. So, back to the drawing board again! Third time is a charm and since the cover fits, looks great and is made to last, you are going release it into the world. 

Now you are left with two “failed” prints, 6h print time and also one whole afternoon tinkering with CAD. How can this be a good thing if you might have a half way decent cover on the first try?

How I use 3D prints:
If i print something, it is most likely designed to be used outdoors, to be handled a lot or to be robust in general. Time and time again i saw parts fail because they are designed with some flaws, shortening the life span. So i had to redesign/reprint them anyway. I also tend do avoid using a part if it looks like a bag of screws or is unpleasant to work with in general (no matter if it does its job or not).

I Immagine others to act similar and so i think about it like this:
Lets take the immaginary cover from above, 100g material use, 2h print time. Uploaded to a file sharing platform as is, downloaded 50 times over 1 year time. Lets also immagine it is also printed 50 times in the real world by other users.

This is going to cause 50 users to grind down some filament in order to make it fit, lets say 5g each. Also they have to spend some time doing so. Maybe 10min. Now we have 250g filament wasted and also 500min of "labor" spend for nothing. Now, because this first itteration cover looks a little clunky and also starts to leak after some time, 20% of the users stop using it or thwrowing it away because its broken. 
Now we have to add 500g of wasted filament, and 10h of wasted printer time. You see, this adds up fast. The magic of scale!

This whole topic is broken down to a hillarious degree, i know, but i think the main point came across. Some wasted time and grams of filament on my/your side are going to save a multiple of that to others on the long run. I think there are many cases where this might not be true or even more true. Its like all in live, many shades of gray and all in between. In general this whole concideration might be on the “more true than false” side though ^^ All in all, I tend to mess up something around printing and designing all the time. like everyone else too I guess. but in the end, it might be the right thing to consider some of the above, some good practices and most importantly having fun with this awesome hobby and the whole maker community 

Thats all for today
Cya