80100 direct cooling

I used a WAM silicone turbo hose to fill magnet. Fit the hose then just pour epoxy in the gap. It worked quite well, I just had to sand a bit to have it nice and clean


An item that many people here were thinking/dreaming about to ease the task. There are some on eBay but would you have a link ?

60mm - 50mm reducer

OD is arround 70mm, perfect tight fit for the 83110. Not sure if it is exactly the same as the 80100. Being silicone it self release.



What is the length of the 70mm OD tube ?
Was it long enough to cast the resin inside the rotor in one shot ?

Very handy that tube. I just got a pièce of rubber and rolled it up. I cut with siccors untill the roll was exactly the size to sqeeze inside. And used silicone spray so it will not glue to inside.

About the magnets. Maybe just spray some cheap primer paint on top? Or hammerrite ? Thats the name in Holland for primer painting metal

I used usual lamination epoxy, covered Stator and magnets and let drip off, what was too much. No problems after reasambeling. It gave a nice thin coat.

It is 68mm and cover full length. After a quick sand I used 2 coat of 2k epoxy called durepox from Resene automotive. It is a metal primer also used on Anerica cup and kite race foil.

Hi Mat, do not give up. I also scratched my magnets in the lathe after epoxying when i wanted to get rid of the abundant material. I just took a sponge, soaked some epoxy and whiped this over the clean and smooth surface. Maybe it does not work after using corrosion spray any more. Maybe also the stator became to thick after epoxying?

I went back to spray but used a clear coat automotive one, it might survive the salt water better :slight_smile:
I need to get back in the water anyway to get data with a different wing …

Did someone ever modified a 83110 from delta to star and tried on the foil? I modified mine, it did lower the kv from 180kv (specs) to 107kv (mesured on the bench).
If I’m correct the factor 1.73 apply also to the torque and should get the 6.5NM of the specs in delta to 11NM in star correct?

If this also works for inrunners, we could use a 192KV from Reacher Tech, Maytec (or family). 192/1.73 = 111kV :thinking::crossed_fingers:

They told me the lower kv like the 120kv are star

Just a thought, what if we print a prop with a ring attachted around the propblades ? Much safer and less drag through the water because you don’t need a mount anymore. Yes the ring will spin around but that will not cause injury as a boatprop.

I thought about it too, but it has been tested and is not a good idea unless you have a lot of power to spare.

Thanks, in your link is a picture with good results. Maybe another design prop with ring and testing once again ?

May be with a thinner ring like in the paper, it will reduce the extra losses and you can get closer to regular prop efficiency…
I’m not sure how printable it’ll be though…

@superlefax, did you give it another try?

Well, I could not even got to decent speed. The amperemeter showed over 100A for 20km/h. I was really surprised on this. I’m not really sure what exactly caused that drag.

That’s why I gave up on that one.

But of course its always a good idea to try it again with a different shape. It would be great to find a working solution which maybe has less drag than a fixed duct.

What about blades offering curved but short winglets at their extremities so that there is not cutting angles if in contact with a person or an animal ? Like planes in fact ?

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Here the illustration of what I had in mind: scimitar blades from modern submarines. You will notice that to bring the safety aspect, the winglets must be bent towards the opposite side of prop rotation direction.

In fact rotating winglets during rotation create a solid ring. Of course, the blade extremity must not be sharp and dangerous like scimitars. They coul be thickened like an olive.

Applied to @foiledagain 156mm prop, this is in yellow what it would look like adding a tiny appendix to smooth the edge:

found the submerged data: S9tim's 80100 direct drive
So it’s something in the low 900W

I just changed laptop so my recorder setup is messed up… but from what i saw, when trying to fix my receiver full speed in air is in the 160W range
i’ll try to run it wet soon just to be sure to compare apple to apple

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