Old props

[SteveinVA]

Just wondering what you guys have done with them. Mines not terrible, Its aluminium and has about a dime size chip in one of the blades. I have heard of them being repaired. IDK I put mine on CL for 20 bucks, we'll see what happens

 

[Grub54891]

Re: Old props

Have em reparied, use it for a spare...

 

[Scott Danforth]

Re: Old props

the guys at the local repair shop know me by heart.

$75 to repair and $90 to rehub is much cheaper than a new prop.

 

[limitout]

Re: Old props

AFAIK if the chunk is missing it cant be replaced (im told any welded sections are going to be brittle and will just break off again) so it is my understanding the only repair method that works and is reliable is heating and rebending the pitch and cup and grinding blades down so they are evenly shaped and in balance so they can never add anything "missing" back onto the blades. translation, if a chunk is missing it is gone and cant be replaced. other then a complete replacement blade ear being welded onto the hub that is.

is my understanding on this incorrect? if not, how can a welded joint hold up to the stresses of the blade that flexes under load?

 

[steelespike]

Re: Old props

A properly repaired prop will last a long long time if you don't whack into something.
If you have a motor with an older prop, lets say over 20 years ,and a modern day prop is available keep the old one for a spare
and buy new. Very likely will be of a more modern design and deliver up to date performance.

 

[Scott Danforth]

Re: Old props

AFAIK if the chunk is missing it cant be replaced (im told any welded sections are going to be brittle and will just break off again) so it is my understanding the only repair method that works and is reliable is heating and rebending the pitch and cup and grinding blades down so they are evenly shaped and in balance so they can never add anything "missing" back onto the blades. translation, if a chunk is missing it is gone and cant be replaced. other then a complete replacement blade ear being welded onto the hub that is.

you really ought to do a google search or even a youtube search for propeller repair.

very few materials can not be welded and repaired. Aluminum, Stainless, and Brass can be repaired easily.

go get any welded joint to hold up to stresses is easy. use the correct pre-weld prep and post weld operations for the loading at hand.

 

[phillyg]

Re: Old props

I had the same aluminum prop repaired three times for much less than a new prop. The damage was not the result of re-fixing prior damage.

 

[dingbat]

Re: Old props

internet welding technologist......a weld is stronger than the base metal. The weld will be there long after the rest of the prop is scrap

 

[smokeonthewater]

Re: Old props

I can get new props for $100 for my mercruisers and new hub kits $30....

small repairs are worthwhile but it doesn't take a whole lot of damage for it to be cheaper to replace it.... best bet is take the prop to a local shop.... if it's too far gone to be worth fixing he'll probably tell you before you even make it to the counter LOL

 

[limitout]

Re: Old props

internet welding technologist......a weld is stronger than the base metal. The weld will be there long after the rest of the prop is scrap

you are right, the weld will be there, because a weld makes a hardened rigid bond that cannot bend or flex it can only crack and that is why you cannot weld anything that flexes or the metal will just crack on either side of the welded area and when you weld that crack it will crack again further over.

if you are going to weld on a prop you can only do it at a spot that does not flex such as the hub or the base where the blades meet the hub

 

[Scott Danforth]

Re: Old props

thats funny, they have been welding things that flex for many many years

we do it all the time at work. maybe I should tell the whole company we have been doing it wrong

 

[Bondo]

Re: Old props

you are right, the weld will be there, because a weld makes a hardened rigid bond that cannot bend or flex it can only crack and that is why you cannot weld anything that flexes or the metal will just crack on either side of the welded area and when you weld that crack it will crack again further over.

if you are going to weld on a prop you can only do it at a spot that does not flex such as the hub or the base where the blades meet the hub

Ayuh,.... I'm with Scott, that's just Untrue,...

Not only do I weld alota different things of different metals,...

I've watched props bein' rebuilt at Don's Prop Shop, in Clayton Ny, Don bein' a Good friend of mine,....

Many props have their outer 1/4" of of blade welded back into shape, then ground down, repitched, 'n cupped,....

Both aluminum, 'n SSteel,...

 

[Frank Acampora]

Re: Old props

Well, Limitout IS partially correct: All props in all materials are cast. It takes a very skilled welder to properly repair a cast prop. Any old welder simply will not do well. Good prop shops do have the skills and finding one is like finding a good mechanic.

Skips Props in Reading closed shop a number of years ago. THEY were good. NOW, the prop shops marinas send their props to around here in many cases just don't weld. I sent a beautiful stock Chrysler stainless prop with some edge damage out for repair. For 90 bucks, the Esso Bee simply ground the edge, re-contouring the blade shape and reducing area. I was livid. I met with a rep and he told me that that is the way prop shops here in eastern PA do repairs. They simply do not weld if at all possible. The prop also had some relatively deep corrosion pitting on the blades. They said that any weld repair would pop back out. I also sent a small 9 inch aluminum prop out and it came back more broken than before with a note saying it was not possible to weld.

Bondo: If Don is that good, send me his business phone or email in a PM.

 

[Bondo]

Re: Old props

Well, Limitout IS partially correct: All props in all materials are cast. It takes a very skilled welder to properly repair a cast prop. Any old welder simply will not do well. Good prop shops do have the skills and finding one is like finding a good mechanic.

Skips Props in Reading closed shop a number of years ago. THEY were good. NOW, the prop shops marinas send their props to around here in many cases just don't weld. I sent a beautiful stock Chrysler stainless prop with some edge damage out for repair. For 90 bucks, the Esso Bee simply ground the edge, re-contouring the blade shape and reducing areaView attachment 219421View attachment 219422. I was livid. I met with a rep and he told me that that is the way prop shops here in eastern PA do repairs. They simply do not weld if at all possible. The prop also had some relatively deep corrosion pitting on the blades. They said that any weld repair would pop back out. I also sent a small 9 inch aluminum prop out and it came back more broken than before with a note saying it was not possible to weld.

Bondo: If Don is that good, send me his business phone or email in a PM.

Ayuh,.... Just google "Don's Prop Shop, Clayton, Ny."......

Nevermind, I did it for ya,....

Don's comes out on the top of the search,.... they don't have a website, but are listed with phone numbers,...
Don runs the Shop, along with his Dad, 'n brothers,...
Don's wife, Deb, runs the store, 'n will probably be who answers the phone,...
'n, Yes, they're open year round as it's as much a Machine Shop, as a Prop Shop,....

'n oh, btw,.... Mention my name, it may not get ya a discount, but it will get ya Great service,....
Bill Bond,....

 

[Scott Danforth]

Re: Old props

Frank it sounds like you have been taken. You could also use Green Bay propeller service in Green Bay Wisconsin or General Propeller down here in Bradenton Florida I prefer General Propeller

both have welded nearly half a blade on my paper-thin VP DP props. General Propeller will even rehub volvo props (one of 2 shops in the US that does rehubing of volvo props)

http://www.generalpropeller.com/services
http://www.greenbayprop.com/content-pages/page-prop_skeg_repair

 

[limitout]

Re: Old props

Ayuh,.... I'm with Scott, that's just Untrue,...

Not only do I weld alota different things of different metals,...

I've watched props bein' rebuilt at Don's Prop Shop, in Clayton Ny, Don bein' a Good friend of mine,....

Many props have their outer 1/4" of of blade welded back into shape, then ground down, repitched, 'n cupped,....

Both aluminum, 'n SSteel,...

well its hard to get accurate info because the process is everything at not all shops do the same work or do the same work the same way.

as you know not all welders are equal in skill so what they do varies and I do not know if maybe they do something like heat treating the repair to remove the hardening of the welded section after welding.

im not looking to argue any of the points here but only to learn (especially since I am not a welder) if there is more to the process I am not aware of.

all the welders I know say you can weld anything anywhere anytime but some things will always crack again and WILL need rewelding over time and they all agree a welded joint that gets flexed will crack and "according to my welder buddies" they said you cant get a permanent repair by welding that. if the weld is on a part that flexes but the weld itself doesn't flex then it "should" hold since the weld itself isn't what flexes.

I have never seen or herd of any prop repair shops in my area that did anything other then grind blades down evenly and rebend pitch and cup. I guess it comes down to talent but if we ever brought in a prop with a "chunk" missing then it was called unrepairable and they told us to buy a new one. dents were beatened straight and dings were filled down for evenly profiled and balanced blades but that's about it.

 

[smokeonthewater]

Re: Old props

in this world it is EASY to find an expert to answer a question.... Not so easy is verifying that the expert knows what they are talking about....

I had a conversation a few years ago w my prop guy... I took him a prop with heavy damage to all 3 blades... he said it wasn't repairable and I asked why... He explained, well, actually it IS repairable and would be no problem... he charges $60/hr and it would take close to 3 hours..... I said "that's more than a new prop" he said "That's why it's not repairable" LOL

To try to learn all the ins and outs of welding and prop repair from a quick internet conversation is unrealistic..... Learning to correctly repair a prop isn't just learning what to do but rather it's learning the many many things NOT to do...... It's about understanding how the repairs fail and being able to see the forces that act on the part.... Doing it well comes from years of practice....

The thing for us to understand is WHO to take the prop to and when it's worth it vs when it's cheaper to just buy a new one.

 

[dingbat]

Re: Old props

you are right, the weld will be there, because a weld makes a hardened rigid bond that cannot bend or flex it can only crack and that is why you cannot weld anything that flexes or the metal will just crack on either side of the welded area and when you weld that crack it will crack again further over.

Thanks......I would have figured with my 4 years of professional welding school, more TIG and MMA (ferrous and nonferrous) certifications than I carry in a wheel barrow and 30 some odds years in metallurgical process control with the likes of Alcoa, Novelis, Aleris, I would have experienced this for myself.

The next thing your going to tell me is that you can't weld steel and aluminum together:noidea:

 

[Scott Danforth]

Re: Old props

The next thing your going to tell me is that you can't weld steel and aluminum together:noidea:

well.....not easily anyway. need a duplex alloy in between

 

[dingbat]

Re: Old props

well.....not easily anyway. need a duplex alloy in between

Nope... FSW...Friction Stir Welding. The method has been around since the early 90's. In a sense, a variant on explosion bonding.

I did some work several years ago with a company that was "cladding" titanium with a "secondary" material in a similar process in an inert environment. I knew they where doing work in the area in years past, but didn't know how far they had come.

Here is Honda's news release on the technique they perfected

Honda Worldwide | September 6, 2012 "Honda Develops New Technology to Weld Together Steel and Aluminum and Achieves World's First Application to the Frame of a Mass-production Vehicle"