P1 Puma RIB racing-scratch building

[Dirk Jan]

I'm curious how the outboard will perform Dim. Also, that SSS motor you scored is a nice one!

I did 7 runs on the large TFL outboard leg, with 3 different flex shafts. None of them actually broke, but I experimented with several couplers.

So far so good on that outboard. I had no breakdowns yet. I heard some negative story on the large TFL leg by forum member Mantaray1969, but my experience is positive so far.
I do lubricate it very well. The flex shaft and bearing have grease inlets and I bring a can of WD40 to the water, to spray a little into the leg after 1 lipo.
Also, I take the flex shaft out after I ran the boat. I clean it with a rag and lubricate it with ball bearing grease.

The rpm is 1650 x 6 x 3.7 = 36.630rpm unloaded.

My mini TFL spins 2600 x 4 x 3.7 = 38.480rpm unloaded.

In that sense, my mini TFL gets a harder beating [emoji28]

 

[Dim L]

I do lubricate it very well

This is the key Jan. This is why you ran smoothly with your outboards...

 

[Unusual RC]

Great idea!

Just a little bit of my experience with comparing drives using the same motor, Esc and lipo's.
If I would have taken top speed as the factor of comparison, I had to compare 45,0kmh, 42kmh, 43kmh and 41kmh.
All on 4S.
However current was 160A, 130A, 95A, 110A respectively.
The first had a wrong CoG, which made it run faster. Still this drive had the most resistance. The Esc just put more power in the equation to get maximum rpm.

If you have a current meter as well, that would be even better.

What you build yourself can be better than most commercially available. You put more time in it to make it as you like then they can spent in the factory keeping things profitable.

 

[Dim L]

If you have a current meter as well, that would be even better.

You are right Michael.
I guess this is a way to determine the efficiency of each drive, isn't it?

Meanwhile, releaseing was such a success for the first time...

The mold has no damage and the cowl is smooth and super light...

 

[Unusual RC]

You are right Michael.
I guess this is a way to determine the efficiency of each drive, isn't it?

Exactly!
I have to admit I also initially thought that better efficiency brings more speed.
In reality with electric drive it is just more efficiency.
And more efficiency means you could run a higher pitched prop (or larger diameter) while using the same amount of current!
Then top speed will increase.
I am myself in that phase too (and going from 4 to 6S...)

Well done, you know how to make a mould for sure!

 

[Dim L]

Update #20: Building the stern and triming the cowl.
Goodmorning guys! Let me share with you my progress on my Diy rib.

The hull weighs less than 1000 gr with the cowl, so the goal of 1100 gr is feasible.

I have a question for you guys that have more experience than me.

What propeller do you recommend to start with?
I synopsize the tech characteristics of the boat.
Lenght ~ 80 cm
Weight ~ 2.5 kilos ready to sail
Battery 4s
Motor sss 2960, 2200 kv, max power 1300 watt.
I would say something between 36 and 38 mm, 1.4 pitch for beginning.

 

[Dirk Jan]

Looking great Dim [emoji106] Weight and planned setup sounds like a good combination.

I would start with a 36mm 1.4 pitch prop and check the motor / esc temperature and run time. If that didn't reach the limits, you could go bigger / more aggressive.

How about the finish of the hull? Partly carbon I read. Did you plan the colors already?

 

[Dim L]

Thanks Jan for the advice . I will start with a 36 mm 1.4 .
Well about the colors. The main color it will be white. The tubes will be white and light Grey. The upper deck will have red and silver (probably a line from the bow to the start of the cowl or sth similar) and I am planning to leave a small area at the top of the cowl as carbon.
I have chosen these colors on purpose because I am planning to paint the cover of the outboard white-red-black with the new mercury racing 300 stickers see below:

And few stickers of course (with a water slide decal paper like your technique): the name of the boat, mercury stickers and probably a number or sth similar.

 

[Dim L]

Update #21: outboard cover release.
The release was not that perfect as the cowl but generally was OK.
I glued the two halves with CA glue and then I applied 4 layers of 50 gr fiber on the one side. Then sanding and laminating the other side.

I hope you have a nice and productive week.

 

[Dim L]

Update #22: Laminating the inner of the hull and the transom.
The bottom with 180gr carbon and the polyertherne at the tubes with one layer of 110 gr fiberglass.
These cf edges are very annoying. How do you stabilize them guys?

I do not like the looks of the laminated polyertherne but it is functional in terms of waterproofing and weighs less than plywood, so, I can live with that .

 

[Dim L]

Update #23: securing the cowl on the outboard and mounting the outboard on the transom.

Total weight is about 2 kilos until now.

 

[Dirk Jan]

Looking good Dim! I really like that outboard with the aluminium and cf parts. It became a very nice unit.
Not to mention the boat.. with the stringers still visible at te transom, cf on top.. It looks fast sitting still; it has a nice stance. Great engineering [emoji106]

 

[Dim L]

Oh thank you so much Jan for your kind words
!!!
It would be great to be fast at the water too .
Let's see how it performs, I am very curious for both the outboard and the hull.
Bytheway the cowl has enough room for a 3660 motor so if I want more power an sss 3660 1650 kv 1800 watt would be great.

 

[Unusual RC]

Wow! This one is looking cool!

You can put this already on a cupboard in your house! She is looking very fast indeed!
CF black, aluminum...what Dirk-Jan says, very cool material mix!

 

[Dim L]

Thanks Michael !!! Yes this is a nice photo.
As I said to Jan in the previous post I am very curious about the performance of both the boutboard and the hull. I hope that what it looks fast is indeed fast when it sails...

 

[Dim L]

Update #23: DIY radio plate and servo holder.
Hi guys I hope you are having all great time. The weather is getting really warm here in sunny Greece (29 degrees yesterday) and I am looking forward to sail my boats again. (Bytheway, my Cosy is again on the operation table because on of my cats throw it down from 2 meters height. Fortunately not big damage).
Let me share with you my latest progress.

It weighs ony 14 gr, light and strong.

Since I made the outboard I feel much more confident when I work with aluminum and cf and I can say that now I love working with these materials.

 

[Tamiya1970]

Update #23: DIY radio plate and servo holder.
Hi guys I hope you are having all great time. The weather is getting really warm here in sunny Greece (29 degrees yesterday) and I am looking forward to sail my boats again. (Bytheway, my Cosy is again on the operation table because on of my cats throw it down from 2 meters height. Fortunately not big damage).
Let me share with you my latest progress.
Bekijk bijlage 489604

Bekijk bijlage 489606

Bekijk bijlage 489607

Bekijk bijlage 489608

It weighs ony 14 gr, light and strong.

Bekijk bijlage 489609

Since I made the outboard I feel much more confident when I work with aluminum and cf and I can say that now I love working with these materials.

Very nice Dimm,and fun to make it your selves.

 

[Dim L]

Indeed Alex, it is a lot of fun and you save money as well !

 

[Tamiya1970]

Indeed Alex, it is a lot of fun and you save money as well !

Saving money is good [emoji16][emoji1305]

 

[Dim L]

Update #24: Esc water inlet