What's Paul up to?

[Susquatch]

I bought one of those one size fits all from Busy Bee I never could get it apart after the first use.

Yeah, that's basically my analysis after looking at them for a bit. Knowing how I killed my first 3, there's no way the one-size would have survived.

I have one of the busy bee stepped units too. Not saying I love it, but mine is still working after at least 2 dozen parts. Might be the size of my blades. I don't like thin ones.

I still have it in my mind to make a good low profile one some day. It will have a button head and a flush cone head machine screw to hold the head on.

 

[PaulL]

Not much machining - just got back from two weeks in the Mexican sun, in the Yucatan and Lake Chapala regions. But no machining.
And the synthesizer debug/repair is going badly: looks like my ROM isn't giving back any data, which is strange and vexing.
But maybe there is a tiny bit of machining content. This lovely thing just arrived after a several month wait:

The thing is *sharp*. I Mena, nicely polished, etc, but also *sharp* as in "use the enclosed gloves to avoid cutting yourself".
It will be going on the boat this Friday and we'll see if their 20-30% estimated fuel efficiency improvement materializes.
These props are a great example of semi-custom manufacturing enabled by CNC. I had to do some sea trials with my existing prop to get some data points on speeds at RPM and trim, which are then used to customize the prop for the particular boat and engine. They have a small number of casting patterns, and then the rest is done in a CNC mill farm.
This (horribly over-youtubed) video gives an idea of the milling process:

And yes, I could have bought a nice mill for the price of the prop. But it will be nice to get to the fuel dock 25-30% less often, and the fuel savings should pay for it in about 5 years.

 

[140mower]

Not much machining - just got back from two weeks in the Mexican sun, in the Yucatan and Lake Chapala regions. But no machining.
And the synthesizer debug/repair is going badly: looks like my ROM isn't giving back any data, which is strange and vexing.
But maybe there is a tiny bit of machining content. This lovely thing just arrived after a several month wait:
View attachment 45435
The thing is *sharp*. I Mena, nicely polished, etc, but also *sharp* as in "use the enclosed gloves to avoid cutting yourself".
It will be going on the boat this Friday and we'll see if their 20-30% estimated fuel efficiency improvement materializes.
These props are a great example of semi-custom manufacturing enabled by CNC. I had to do some sea trials with my existing prop to get some data points on speeds at RPM and trim, which are then used to customize the prop for the particular boat and engine. They have a small number of casting patterns, and then the rest is done in a CNC mill farm.
This (horribly over-youtubed) video gives an idea of the milling process:

And yes, I could have bought a nice mill for the price of the prop. But it will be nice to get to the fuel dock 25-30% less often, and the fuel savings should pay for it in about 5 years.

.....you know, you probably should have bs'd us and said " Look at what I made these past 2 weeks!"
Having seen some of the things that you have done, I would have believed ya.....
Noticed that you were a little quite lately, figured you'd be somewhere warmer than where I am.....

 

[PaulL]

Noticed that you were a little quite lately, figured you'd be somewhere warmer than where I am.....

Yeah, between warm places to be and a bunch of winter maintenance at the cabin and then this crappy synthesizer using up my time(in a good way!) I just haven't had a ton of time in the shop.
Though I did get the spacers for the casters for my acorn table done: not exciting, and I'll post more once I get them mounted underneath properly.

 

[jcdammeyer]

Yeah, between warm places to be and a bunch of winter maintenance at the cabin and then this crappy synthesizer using up my time(in a good way!) I just haven't had a ton of time in the shop.
Though I did get the spacers for the casters for my acorn table done: not exciting, and I'll post more once I get them mounted underneath properly.
View attachment 45438

Do you have any dip for those chips?

 

[Susquatch]

But it will be nice to get to the fuel dock 25-30% less often, and the fuel savings should pay for it in about 5 years.

Fuel savings my ass. We know you are really after the extra top end that should come with that efficiency! The question is, did you choose the right pitch so you don't run out of rpm......? It's not like you have a rack of them to test to find the right one!

Hey - @TorontoBuilder and @Matt-Aburg - are you guys lisnin? Seems @PaulL has one of those fancy new props you guys were droolin over and modelling in Fusion. Some of the best reading I've had on here!

PS Paul - Congrats! Can't wait to hear the results!

 

[6.5 Fan]

So is the idea behind the sharp edged on the prop used for chopping rocks when you get to close to shore.

 

[DPittman]

So is the idea behind the sharp edged on the prop used for chopping rocks when you get to close to shore.

I think it's to cut up bathing suits as the material can jam up on the props when you go through swimmers.

 

[YotaBota]

I Mena, nicely polished, etc, but also *sharp* as in "use the enclosed gloves to avoid cutting yourself".

I was thinking sushi in your wake.

 

[PaulL]

I was thinking sushi in your wake.

Props are generally terrifying things. I never want to be in the water with one.

 

[PaulL]

Fuel savings my ass. We know you are really after the extra top end that should come with that efficiency!

Part of me wishes. But cruising around at 25 knots is already plenty scary. The amount of debris in the water around here takes full attention!
The performance curve on these is interesting though. They seem to perform best in the 3500-4500rpm range, where you get serious efficiency and performance wins relative to RPM. The efficiency drops to match conventional props at higher revs again, I assume because cavitation starts happening again, etc.
I generally run at about 21kts at 4200 rpm. The hope is that this prop will give me that at about 3500-3700rpm instead. Quieter and less fuel. If the weather holds up I'll have a chance to sea trials it on Friday morning.

 

[TorontoBuilder]

Props are generally terrifying things. I never want to be in the water with one.

I can attest to that, in high school a very close friend of my brother and I had his boat run into by an impaired woman driving a typical runabout. His leg was run over by the propeller, and the leg basically severed into chunks as if by a maniac wielding a clever.

They said it was a miracle he survived to be rescued. His friend kept him afloat and from bleeding to death.

They said it was a miracle he survived the transport to the hospital... it was. They said it was a miracle he didn't lose his leg... but he had a half dozen surgeries and wore multiple casts for over 2 years.

When I'm on or in the water in Ontario's cottage country I'm nearly terrified of drunken boaters

 

[Tom O]

Glad you got the Pro-peller and not the amateur one.

 

[PaulL]

First impressions on the prop: Yes, it's definitely got more bite, even at low revs. At 600 rpm I had full control of my stern, both forward and reverse. But the exciting part was getting on step at about 3200rpm instead 3800-3900. And cruising across at 21kts at 3900rpm instead of the usual 4500. So there's certainly some benefit there. I'll know in about 100l of fuel how much it will come out to.
It's also *much* quieter under way. It wasn't comfortable to have conversation at 21kts previously, and on this crossing we found it easy to keep chatting. So a big win already.

Paul

 

[Dabbler]

It sounds like they actually work!

 

[PaulL]

Finally got the casters under the acorn table. Glad to have my mag drill to make the bolt-holes. Some sort of screw-down leveling feet will go in the corners.
But now that it's mobile I can get a start on the long-awaited Blanchard grinder.

 

[mbond]

Now I know how to forge a trailer plate!

 

[PaulL]

Now I know how to forge a trailer plate!

I totally forgot to blur that!

 

[jcdammeyer]

I totally forgot to blur that!

I thought you did a great job of forging someone else's trailer plate number on top of yours.

 

[Susquatch]

I totally forgot to blur that!

Fixed.