Propeller Blade Thicknesses.....

[ThrottleUp Props]

Hey Guys....I thought we could talk about "Propeller Blade Thicknesses". This is a characteristic of newer origin, to both racers and the private sector. But, none the less, a VERY IMPORTANT aspect when purchasing propellers, new or used.

It has become painfully clear that blade thicknesses are not being considered or thought of during the propeller purchasing process.

So, I thought I would start this thread to get some real life scenarios.

What is your HP and what is your blade thickness?

Do not worry if you do not know, check your propellers on the aft end.

You may see the manufactures name, the propeller size, serial numbers, blade thickness and manufacturing date. It will not have all of this info but it will have some of it.

So before you start the season lets make sure your propellers are what they need to be.

Safety first, as they say!

Julie

 

[glh]

Ok,

Mine say ;
Throttle Up 16 3/4 x 36 18
Got them from joe in Houston TX

For a 42 MTI with drysump transmissions and 850's

 

[ThrottleUp Props]

VERY GOOD GLH!!!!!!!!!!!!! Your propeller thickness is 850 HP rating.

Congrats!

Julie

 

[glh]

Does that mean no chillers and smaller pullies mommy?

 

[ThrottleUp Props]

I actually have a 4 week production time as of today. However several board members have thrown blades already this year with catastophic damage.

So onebadinjun....what is your contribution to the HP boating world these days?

Care to man up?

Julie

 

[ThrottleUp Props]

Does that mean no chillers and smaller pullies mommy?

Not to exceed 1000HP....my son!

Julie

 

[Dan Adams]

On the 42 fountain w/525s was running 32p 5 blade labbed mercs. They break off about an inch up from the hub. The thickess area at this point is .325". I have broken two so far with this mild setup. I'm currently running the same props, except non-labbed.

 

[shifter]

Julie makes a very good point.

I have had several customers try props not looking at the blade thickness and ended up failing very quickly. They can be cut for a 525 spec or a 850 spec and you are pushing 1400 hp. That is why there is a mandated thickness in racing.

The props also have a fatigue life so be carefull on used props. Watch out for the dings on the leading edges they lead to cracks.

pat W

 

[ThrottleUp Props]

On the 42 fountain w/525s was running 32p 5 blade labbed mercs. They break off about an inch up from the hub. The thickess area at this point is .325". I have broken two so far with this mild setup. I'm currently running the same props, except non-labbed.

Dan,

Your biggest challenge or issue is that you are surfacing high round ear props which were not designed to surface pierce. I am afraid with your exsisting drive heigth you will most likely continue to do so. You may want to consider changing your drives or props.

Julie

 

[ThrottleUp Props]

Julie makes a very good point.

I have had several customers try props not looking at the blade thickness and ended up failing very quickly. They can be cut for a 525 spec or a 850 spec and you are pushing 1400 hp. That is why there is a mandated thickness in racing.

The props also have a fatigue life so be carefull on used props. Watch out for the dings on the leading edges they lead to cracks.

pat W

ABSOLUTELY ON THE MONEY PAT!!!!!!!!

Thank you for sharing expertise with everyone!

Blade thickness was not an issue when HP was at 500, but in the last 10 years it has increased substantially and so has blade failure rates.

Julie

 

[cigdaze]

If you can't say anything nice, then......

Check your propeller blade thickness at the start of the season...COME ON!!!??? I know things are slow, but this takes the cake. I've heard just about everything now.:rofl:

I'm not quite sure what it is about this that you find funny.

I've tossed a blade before and I can tell you it's no fun at all. I got lucky that the only thing damaged was the prop, but it can get pretty ugly if a blade launches into something else on your transom.

People buy and trade labbed props all the time on this forum and if a prop was worked for an intended power (thrust) range, and you unknowingly exceed it, the results will speak for themselves. And it's not just thickness you should be checking, as mentioned above, small nicks, scratches and dents/dings can work themselves into catastrophic cracks given enough time with the oscillating loads involved here; fatigue can and will come quickly with props.

 

[Dueclaws]

I have Merc CNC 5 blades: 16.5 x 36, 18*, 1075 HP blade. My engines are about 950 HP, so (probably) the thicker blades are unnecessary.
If they had been available, would've bought those 850 HP TU props from Joe.
My test-time-only Mercs are for sale BTW.
;-)
Due

 

[Sean H]

just need a set of these... :sifone:

 

[sellsman11]

just need a set of these... :sifone:

 

[wiggler4490]

just need a set of these... :sifone:

Sean what are they

 

[ThrottleUp Props]

I have Merc CNC 5 blades: 16.5 x 36, 18*, 1075 HP blade. My engines are about 950 HP, so (probably) the thicker blades are unnecessary.
If they had been available, would've bought those 850 HP TU props from Joe.
My test-time-only Mercs are for sale BTW.
;-)
Due

You are absolutely correct. I would not have built the wheels for 1075 either. With 950's you would be fine with the 850 thickness. Let me know if I can help you with a set.

Julie

 

[ThrottleUp Props]

just need a set of these... :sifone:

Now that it is out there guys....this is the newest propeller process we have available to all of you!

The props in the pictures posted b Sean H are Throttle Up Propellers CNC Suface props with a PVD applied. PVD is "Particulate Vapor Deposition". This formulation is designed to increase the strength of the propellers.

Stay tuned as more information becomes available on the features and benefits!

Julie

 

[Dueclaws]

Julie-
OK. Let me sell the Mercs and will contact you afterwards.
Thanks
John

 

[Davidmnc]

just need a set of these... :sifone:

If there is such a thing as a sexy prop...........these are them! :drool5:

 

[Dock Holiday]

Good thread Julie

I know first hand what it feels like to have a blade decide it wants to leave the family. That is one wicked vibration!

I never have heard this before about a minimum blade thickness and labbing for the horsepower and find it very interesting. The prop pictured was the fastest set of props I ever owned after working them twice and they did not last one full season. I guess I know why now. Yes they were THIN baby!

P.S. No these were not your props Julie they came from our buddy out of Houston that hosed so many people.