Are there any "Do it yourselfe" Repair guide for propellers & how to balance them?

[satanclause]

Are there any "Do it yourselfe" Repair guide for propellers & how to balance them?

If not i was thinking of restoring mine using the Swedish concreate anvil method & how to water Balance it!

Will take photos to show how to step by step!

/T

 

[Frank Acampora]

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

No, don't use "Swedish Concrete." Use a piece of dimensional lumber end grain as an anvil and a medium weight hammer. I work my props against the upright 2 X 4 of my engine stands.

Props are cast and you only get one bend! Try to remove a wrinkle too fast and metal will snap off. You must slowly work the metal to relieve the stress and to work anneal it so it will not crack.

 

[satanclause]

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

But the Swedish method is to make a cast "anvil" of best blade bodeycoate the top, then rotate blade after blade ontop of it and gently tap the blades Into the same shape. Then using 2 bottles on each side of propeller letting it rotate Free in water to determine correct balance. Down to 1/100 of a gram. Thus giveing the propeller better performance then standard Ones!

The Swedish way make each blade 1/100 mm from eachothers in geometry!

About the thickness of a mosquito wing stretched over the back of a flatbed truck, if mm is a problem :-D

I think i Will have to take some photos on how to do this,
And also how to match blade area and how to battle Sharp the propeller. I'll Be back B-)

 

[jestor68]

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

That sounds interesting; but simply making a cast(pitch block) of the "best" blade does not mean it will be correct. You might end up with three blades out of wack; but at least they'll be consistently out of wack.

 

[Scott Danforth]

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

Not sure how common propeller shops are in your location, however down here in Florida, we have a phenomenal propeller shop that charges a reasonable price. and they guarantee their work.

that being said, here is my "Do it yourself" guide

Remove propeller
drop off at shop
go to lunch with wife
have a few beers
pick up propeller
install.


Unless your "Swedish Concrete" Anvil is hardened tool steel like the propeller shops use, you will get movement with every hammer blow. there is no way you can make each blade within 1/100 mm of each other, even if you were wire EDM machining the blades.

I will give you that you may be able get them within 1/2mm of each other, however with considerable time and labor.

Now, I have straightened nicks and rock dings a bit using my anvil and shaping hammer, even with a hand dolly and hammers However I wouldnt attempt a serious repair.

 

[gm280]

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

But the Swedish method is to make a cast "anvil" of best blade bodeycoate the top, then rotate blade after blade ontop of it and gently tap the blades Into the same shape. Then using 2 bottles on each side of propeller letting it rotate Free in water to determine correct balance. Down to 1/100 of a gram. Thus giveing the propeller better performance then standard Ones!

The Swedish way make each blade 1/100 mm from eachothers in geometry!

About the thickness of a mosquito wing stretched over the back of a flatbed truck, if mm is a problem :-D

I think i Will have to take some photos on how to do this,
And also how to match blade area and how to battle Sharp the propeller. I'll Be back B-)

While I too was thinking of making something similar, I do like your idea(s) about casting a block to use for a backer to work the blades. I also like your idea for balancing the prop. I was looking to build a balancing system similar to what prop shops use, but the water balance sounds neat. What a good idea... I have three props now and one of them was bent from the previous owner when I purchased the boat/motor/trail. But I've since straightened that bent prop and it looks good but I have to make sure it is good and rebalanced... Thanks for the ideas and post. I look forward to seeing pictures...

 

[satanclause]

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

Making a pitch block is the standard way of any propeller repair company. However they send them of to a foundry and have them cast them in iron.
My propeller is from a 1968 500 50HP merc and it use old 11 spline center so getting a new here is kinda hard.
I do also live just under the arctic circle and up here we are used to DIY work.
Thinking offcause to measure up the first blade before i start and c how out of wack it meight be.
As there is a pitch and diameter marking on the propeller that is rather easy to check.
I Will have to make a simple jig for it though.
For rebar in concreate i Will use bits of my horse's tail.
Bellmakers use that for their molds as it holds them togather. In addition to that i Will most likely use woodscrews.
Only problem with the water Balance system is that you need a chalk that work under water. Most crayons do though. With a Axis trough the propeller center and letting it float at 2 bottles at each end and some deturgant in the water you get a system far superior to that of a ballbearing one.

 

[satanclause]

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

Btw i cant take credit of the water Balance system.
The Swedish Genious Johnn Eriksson who invented
The propeller and made the first battleship in the world " Think it was for the Northern states called THE MONITOR"
Came up with that in order to perfectly static balance hes propellers

/Thomas

 

[satanclause]

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

Re: Are there any "Do it yourselfe" Repair guide for propellers & how to balance them

Update on how to balance
A swede friend has used this system.
Instead of marking the bottom blade.

Mutch easyer Was to use spray paint on part sticking up from water.

Then at workshop rotate that line you get 180deg until horisontal a 90deg angle sitting on line at center showing at
Propeller precise heavy point. On backside of propeller blade that is heavy material should be removed. He used a
Schootsh brite paint removal Disc. In the word's of Johnn Eriksson. " Backside of propellers only job is to support the front side" /Thomas