detounge

[camaroboy383]

when a prop is detounged,,

how do you go about detounging your props fella's????

as far as cutting them,,how much is to much???

the gains from detounging??

pics if possible please

alden

 

[RaceCraftBearings]

I am by no means a Prop guy so I have PMed a few of the Prop experts to see if they would like to share some info.

In the meantime here is a diagram of the Tongue area as posted by Marty Davis in his Tech Sheets.

There is some good info in his post here:

Prop Info by Marty Davis

 

[moparbarn]

the advantage/gain to detonguing is that you lose the lowest pitch/slowest part of the blade. you also reduce blade area & increase rpm, without sacrificing "useful" blade area, as in reducing diameter. the first props i tongue cut were X series, before i had seen any M series octura props. i just took a straightedge, set it across the hub & scribed a line along it. cut that off square, then blended the cut into the existing blade contour. after seeing the M props, i realize my cut was more agressive than octura's, but after testing both, i like mine better. more rpm & faster accceleration.

 

[shoboat]

Alden,

You can even go up higher, to the drive dog slot and it will

work even better. I grind them or use a 42" x 1" belt sander

and blend the L.E. corner back into the blade. Usually you need

to add some pitch in the center of the blade or a little cup on

the T.E. to help with the cavitation that you just created. This

all needs to be measured for both blades and a Wood pitch gauge

will help with the added pitch and cup measurements. Just make

sure you are wearing a dual cannister mask and some gloves so

the propeller material doesn't absorb into your lungs or skin.

Any Questions Call Me,

Mark Sholund

231.590.3023

 

[moparbarn]

what marks says about safety equipment is VERY, VERY important!!!!!! beryllium copper is a carcinogen & can cause cancer. but any prop material should be considered dangerous. the metal dust, when inhaled can settle in your lungs. your body will react to it like an oyster to sand & encapsulate it to prevent irritation. that can in turn lead to cysts & even tumors in your lungs. if you don't have the gear needed, BUY IT or leave the prop work to the pros!! not trying to scare anyone out of doing prop work, just trying to scare you into doing it safely . a normal dust mask if ok for all but BC props, for them you will need a good dual filter/hazmat type mask, head sock, long sleeves & barrier type gloves (not cotton, but latex, nitril, or rubber). i do my prop work outside, don't want the metal dust hanging around in the house.

 

[shoboat]

Robin,

Actually Stainless Steel with the higher nickel content is even

worse for you. Complete coverage is the best way to protect

yourself. You cannot put a price on your health and happiness.

Be Extremely Careful,

Mark Sholund

 

[moparbarn]

Robin,

Actually Stainless Steel with the higher nickel content is even

worse for you. Complete coverage is the best way to protect

yourself. You cannot put a price on your health and happiness.

Be Extremely Careful,

Mark Sholund

mark, thanx for that info, i wasn't aware of the stainless issue. as long as i have been in & out of the marine industry, you'd think i would have been told that by some of my former employers......they either didn't know or didn't care.

 

[LarryConrad]

when a prop is detounged,,

how do you go about detounging your props fella's????

as far as cutting them,,how much is to much???

the gains from detounging??

pics if possible please

alden

I use a file. I don't need to achieve a high production rate and don't want toxic dust flung about my work area, so I only use hand powered tools when working props.

 

[BobGutsell]

when a prop is detounged,,

how do you go about detounging your props fella's????

as far as cutting them,,how much is to much???

the gains from detounging??

pics if possible please

alden

I use a file. I don't need to achieve a high production rate and don't want toxic dust flung about my work area, so I only use hand powered tools when working props.

Me Too, File and Wet sand paper.

 

[hugh hargett]

when a prop is detounged,,

how do you go about detounging your props fella's????

as far as cutting them,,how much is to much???

the gains from detounging??

pics if possible please

alden

I use a file. I don't need to achieve a high production rate and don't want toxic dust flung about my work area, so I only use hand powered tools when working props.

Irregaurdless of hand tools and a file ANY abasion to the surface produces airborn dust activities include:melting,welding."GRINDING" ,sawing, "SANDING" and polishing . Not trying to be a smarty but when i read that I almost said "oh okay as long as im using hand tools im okay" Nope not the case.

When youre sanding I hope its wet.I would also do something to make sure im filtering the air breathing in. If you dont do anything but stuff tissue in your nose and pull air through your nostrils only. Anything is better than NOTHING at all.