3D printed rotor!

[handyman902]

So I made the mistake of running my 40+ in a bin without removing the prop. I didn’t get any water flow and upon opening the housing the rotor cam out in 3 pieces. Since ordering the one part will cost $35 Cdn. Likely $20 shipping and the price of the part, I have found someone to measure and 3D print a new one. The measuring, programming and first print was $20 and subsequent prints are $5 Cdn. Or about 3£.
My first issue is I have several from his prototypes to the final prints. Watching several videos on rotor replacement they fit quite tightly. The final printed ones are loose fitting and go on easily. Is it ok to use them or will they just break due to the torque? Is part of the tight fit to keep the rotor from touching the gasket to the gear box? Will it’s loose fit cause the gasket to wear out?
Lastly I asked the guy if he was willing to share the 3D plan and he said it was quite simple and is willing to share. Is anyone interested or would this encroach on the spare parts market, ie will I be stepping on toes?

Handyman902

[Charles uk]

Have you tested one yet?

[handyman902]

Charles uk, not yet. I had a long drive today to pick up the rotors and was hoping for some input on the gasket before I tried one.

[Charles uk]

I don't remember anyone trying this before, you could make the centre hole smaller in very small increments until your comfortable with the fit.
Your going to have to do all the R & D yourself to see if these are viable & most importantly SAFE.

[handyman902]

Charles uk, I’m not printing these myself. I paid someone to do it. It’s a 2 hr drive one way to pick up another one.
My question above about the rotor being able to touch and turn on the gasket being an issue is my primary concern.
The issue with the closer fitting rotors is that they were made with the “fins” pointing the wrong way. I can simply invert it and they will be pointing correctly. Do I need to use a snug fitting rotor or is it ok to just use one that is slightly looser. The difference is about 30/1000” (.030”).

[handyman902]

So I tried several of the rotors for fit and found one that was snugger than the others. It went together just like it should and this time I removed the prop. IT WORKS! I barely had enough gas left in the tank to fill the carburetor, but got it running and below is a pic of the 40+ pissing. It stopped when I idled it, but I think that’s expected.

These are the original & spares, r/h 4 are inverted

Working 3D rotor! Yay

[Charles uk]

Why would you think the rotor blades face the wrong way, the Seagull one has "top end" moulded into the round area on the hub section, certainly on the Century version 100P-1372 & the Kingfisher 15310010 * 8 bladed one, the kingfisher is of the forced type & the century is the swept type as is the 40 version, I assume the swept & the forced differences are due to the internal design of the pump housing.

Before you recommend 3D printed pump impellors could you test them in all sorts of conditions for several days & let us know if they were solid printed or thin wall & what type of plastic was used, as there are some serious safety implications if they stop working or get brittle in cold water, as a seized Seagull won't get you home!

[handyman902]

Charles uk, the 4 rotors on the right in the pic are upside down if you note the round part. The guy doing the printing got the direction wrong for the fins, but easily corrected by inverting them. They are solid, but not sure what plastic was used. I will inquire.
I ran the carb dry after closing the fuel valve and not planning to go boating again this year, but anything is possible. I can do checks at the lake in spring.

[Charles uk]

OOOOPS Your right, sorry didn't notice!