Went 3D

[AKnarrowback]

I thought I'd try an experiment and have my cousin in law (if thats's the right term) 3D print me an impeller liner. The geodesic pattern was on the inside as well but we printed that a little tight and sanded it to fit. There is almost no clearance. I ran it for 45 minutes and had a slightly better hole shot and a 1 mph gain on top. Total cost in materials was five dollars. We printed another with a tighter ID and were not able to sand that one evenly so I did the destructive test and it was far more durable than I thought it would be.

 

[mikidymac]

By the title I thought you bought a Seadoo 3D.

Pretty cool but they will not last as long as a good one but still $5.

 

[JeremyD615]

Definitely cool! I wonder if that printer is big enough to reproduce some of those hard to find 3 degree trim tabs. I would think that polymer would be strong enough to hold up...

 

[Charlie_gtx]

Nice! I think in doing the same when my wear ring wears out, so it's cool to know that it works!

Can you share the STL? What diameter does it have?

Thank you!

 

[AKnarrowback]

Nice! I think in doing the same when my wear ring wears out, so it's cool to know that it works!

Can you share the STL? What diameter does it have?

Thank you!

STL? Is that the file for the ring? I'll see what I can do. He said the program he used for the design was a free one anyone has access to, if that helps. I'll also confirm what material we used, there were a couple choices and we went with the harder of the two.

I forgot the exact dimensions but I had to sand the ID for 20 minutes to get the tight fit. The OD could stand to be a hair bigger for a regular tight fit like a normal liner. As it is it slides into the pump and can be pulled out by hand but is still contacts all around so it centers itself. With a neoprene ring in place the liner is solidly locked in place with the pump bolted in.

Thinking about it it is kind of ideal. I can have one sanded to match my impeller and be able to swap it out without pulling the pump apart, but if the liner is damaged I'm betting the impeller isn't going to be pretty either.

The liner dimensions are for the 140mm pumps on the original DOOs, 89 up era. I'm running on my 94 XP now. I have no idea how it will handle a rock, but when I did the "destructive" test I hit it with a hammer, threw it hard against the concrete and the only hits that produced damage had LOTS of force behind them.

 

[AKnarrowback]

By the title I thought you bought a Seadoo 3D.

Pretty cool but they will not last as long as a good one but still $5.

I don't know if a 3D even exists in the state...

 

[Frank_Hassa]

What's the "destructive test"?

 

[AKnarrowback]

What's the "destructive test"?

Hit it with a hammer, slam it on the ground, get an idea of how strong the material is. It's not a soft plastic at all and it really took some hard hits before it broke.

 

[Frank_Hassa]

Hit it with a hammer, slam it on the ground, get an idea of how strong the material is. It's not a soft plastic at all and it really took some hard hits before it broke.

Thanks for answering. I was thinking about you, your project, etc... just this morning. I was thinking about how the tighter the gap between the blades and the wear ring, the more efficient the propulsion. Why not make the wear ring a little too restrictive, and then let the impeller blades "dig" itself a perfectly tight fit with the plastic?

You could do the "coarse" work with a wrench and once it's free enough to allow the engine to spin the impeller, let normal use finish the job.

 

[AKnarrowback]

The plastic melts pretty quick with friction. A few extra minutes and patience while sanding tuned everything up nice.

 

[Charlie_gtx]

What did you use? PLA or ABS?

 

[hopp]

Charlie_gtx has an important point. If it was printed with PLA and not waterproofed it will biodegrade in contact with water. ABS does not have this problem.

 

[AKnarrowback]

D'oH!

It was PLA.... We'll see how long it lasts.

Still trying to get the file from the computer, I don't have access to the lab where it's at and my :engineer" is out of town.

Going to have him print an ABS liner since it looks like this one will turn into fish food as I ride.

 

[hopp]

That'll be interesting to see. After your post I went looking for PLA degradation time frame and it looks like it should last a season at least.

 

[AKnarrowback]

Well I know it held up good when I pulled a stick through this weekend, what a mess.

 

[Charlie_gtx]

It should last as long as it is not exposed to direct sunlight. I have yo chance mine soon, so maybe i'll do the same.