A friend of mine asked me to print a little blower on my resin printer.
He designed it all and claimed to know what he wants but as he has no 3D printer…
Of course I asked why he wouldn’t just go for one of the many printing services so he could get it printed in much better materials than what I could.
“No need and don’t want to wait two or so weeks to get it…”
Oh well, send me the files over and I see what I can do…
First thing I totally failed to understand was why I should should use my resin printer…
The housing wouldn’t fit as a single piece anyway…
And the actual impeller thingy might have worked out if printed at an angle…
Needless to say that my real concern was his tolerances…
Threaded holes for M4 bolts, a 0.1mm gap between impeller and housing, alignment notches of 5mm with matching slots of also 5mm…
Thankfully he not only provided STL files but also a set of files I could use in my preferred Cad program.
Shaved off those notches a bit, shaved off about 0.25mm from the rotor, removed the threads,…
Of course I just ran it through my P1S using PLA as he ensured indoor use only and only used for blowing air…
Had to do a little bit of fine sanding for those support areas but otherwise was a happy camper.
All fitted together but without the actual motor I couldn’t really test it - turned out in the end it did…
What did I do cheat you wonder?
Well, for starters I added a bunch of evenly spaced hole on the rotor to allow for a balancing if required.
But I wanted to fool my friend a bit and impress him with the quality a ‘resin’ printer can provide…
Means I added a thing spray coat of grey primer, sanded it off to expose areas of concern and repeated this a few times until I got a really smooth result.
Then I added a few coats of heavy duty acrylic spray paint and called it day.
“See! That IS why I wanted it printed in resin, a normal printer just can’t this level of surface quality!” he said and paid me the money for my work.
After he assembled everything and was happy it performed above his expectation and let him know how his little blower really came to be.
Tried a few times but he still thinks I am pulling his leg - not even the clearly different colour in the holes seems to affect him LOL
Long story short - sometimes getting a really nice surface finish is just a matter of a bit of sanding and using the right paint 