Bending Bronze

Discussions about Cape Dory, Intrepid and Robinhood sailboats and how we use them. Got questions? Have answers? Provide them here.

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Oswego John
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Bending Bronze

Post by Oswego John »

Dean,

There have been many good ideas given how to cut the SS pin. You have to decide which option will work for you, all things considered. Maybe, if you are a little hesitant in the use of one method or the other, make some practice cuts on another similar pin held in a vise. This would allow you to gain some dexterity in using a certain tool in doubt to prevent ruining the work. .

Let's go back to the original theme of the thread."Bending Bronze."
Steve Laume wrote:
Why can't bronze be bent cold?

I have flattened some stock but not had that much experience with it. It just doesn't seem like this part needs to be moved that far, Steve.
Bronze can be bent cold. Bronze is somewhat malleable. Just as the pin bracket arm got bent out of shape, it can be bent back to its proper shape.Just think of when you change the pitch of a bronze prop.

If I were to "unbend" it, I would probably apply some force in the direction that it has to go with a monkey wrench or maybe a stillson wrench and tap (not whack) the top of the bracket with a lead or a deadblow hammer. If I were a little squeamish about this, I might first anneal the bracket with a propane or mapp gas torch to a faint, red glow. I wouldn't heat the work above 1200° F. You can ascertain the working temperature of the heated metal by the use of heat crayons. They come in many heat ranges and are available at most places that sell welding supplies. You rub the crayon on the work and if it immediately changes color, the work is too hot. Easy does it with the heat. If you apply the crayon and it just sits there and doesn't melt, the metal temperature hasn't reached the crayon's heat designation.

Anyway, in my mind, the job is doable.

Or, as Robert says, nuke it. :D

Good luck,
O J
Last edited by Oswego John on Jan 20th, '11, 15:36, edited 1 time in total.
"If I rest, I rust"
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Oswego John
Posts: 3535
Joined: Feb 5th, '05, 20:42
Location: '66 Typhoon "Grace", Hull # 42, Schooner "Ontario", CD 85D Hull #1

Bending Bronze

Post by Oswego John »

Dean,

There have been many good ideas given how to cut the SS pin. You have to decide which option will work for you, all things considered. Maybe, if you are a little hesitant in the use of one method or the other, make some practice cuts on another similar pin held in a vise. This would allow you to gain some dexterity in using a certain tool in doubt to prevent ruining the work. .

Let's go back to the original theme of the thread."Bending Bronze."
Steve Laume wrote:
Why can't bronze be bent cold?

I have flattened some stock but not had that much experience with it. It just doesn't seem like this part needs to be moved that far, Steve.
Bronze can be bent cold. Bronze is somewhat malleable. Just as the pin bracket arm got bent out of shape, it can be bent back to its proper shape. Just think of when you change the pitch of a bronze prop.

If I were to "unbend" it, I would probably apply some force in the direction that it has to go with a monkey wrench or maybe a stillson wrench and tap (not whack) the top of the bracket with a lead or a deadblow hammer. If I were a little squeamish about this, I might first anneal the bracket with a propane or mapp gas torch to a faint, red glow. I wouldn't heat the work above 1200° F. You can ascertain the working temperature of the heated metal by the use of heat crayons. They come in many heat ranges and are available at most places that sell welding supplies. You rub the crayon on the work and if it immediately changes color, the work is too hot. Easy does it with the heat. If you apply the crayon and it just sits there and doesn't melt, the metal temperature hasn't reached the crayon's heat designation.

Anyway, in my mind, the job is doable.

Or, as Robert says, nuke it. :D

Good luck,
O J
"If I rest, I rust"
Voting Member #490
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mike ritenour
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The easiest way to cut the s.s. pin is..................

Post by mike ritenour »

A Dremel Tool.

A few years back, in an emergency, we actually cut a 1" dia. shaft with a Dremel tool and its "cut off" wheels.

Mind you, it took a full package of the cut-off wheels and lots of angle cuts, but it did cut the shaft.

The only problem was the Dremel bearings were shot. However, Dremel fixed it under warranty. GREAT Company, Dremel.

Don't forget the safety glasses!
Rit
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M. R. Bober
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Bronze can be bent cold.

Post by M. R. Bober »

It seems apparent that bronze can be bent cold. If not, your bow roller bracket would still have parallel vertical sections.

Mitchell Bober
Sunny Lancaster, (where if something has happened, it is possible) VA
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Steve Laume
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Re: The easiest way to cut the s.s. pin is..................

Post by Steve Laume »

mike ritenour wrote:A Dremel Tool.

A few years back, in an emergency, we actually cut a 1" dia. shaft with a Dremel tool and its "cut off" wheels.

Mind you, it took a full package of the cut-off wheels and lots of angle cuts, but it did cut the shaft.

The only problem was the Dremel bearings were shot. However, Dremel fixed it under warranty. GREAT Company, Dremel.

Don't forget the safety glasses!
Rit
A 4" angle grinder with a thin wheel would have gone right through the 1" shaft and lived to work another day. Those Dremel wheel are rather frustrating, Steve.
Jim Walsh
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hacksaw will do the trick

Post by Jim Walsh »

I replaced all my standing rigging last year and cut every piece to length with a 32 tooth hacksaw blade.
I have a 33 pound Bruce on 100' of 5/16 chain and 175' of 5/8 three strand nylon. I sleep very well. I have a custom stainless roller mounted on my bowsprit in place of the original starboard bow roller so I can't help you with your inquiry as to how the shank will fit your setup. My lunch hook is a 25 pound CQR housed on the port roller.
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bottomscraper
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34 seconds is all it took.

Post by bottomscraper »

I needed a stainless steel straight 1.25" long 5/16" diameter
pin for my windlass. I used a 5/16" 316 SS bolt and cut off the
threaded part and the head. The two cuts were made
with a good quality, sharp but not new 18tpi blade in a high-tension
hacksaw frame. The first cut took just 32 seconds and 34
seconds for the second cut.
Last edited by bottomscraper on Mar 12th, '11, 14:08, edited 1 time in total.
Rich Abato
Nordic Tug 34 Tanuki

Previous Owner Of CD36 Mahalo #163

Southern Maine
http://www.sailmahalo.com
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Steve Laume
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Re: 34 seconds is all it took.

Post by Steve Laume »

The first cut took just 32 seconds and 34
seconds for the second cut.
Dulling blade or tired arms?

Rest time or consecutive cuts?

Or about 30 seconds, Steve.
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Cathy Monaghan
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Post by Cathy Monaghan »

Klem wrote:Dean,

How did this get bent? Is it likely to happen again?

Bending stuff back into shape so that the holes line up correctly can be quite difficult. Would an acceptable solution be to simply cut out the pin and redrill the hole straight while leaving the ear bent? This could be done in place but would not fix it aesthetically.

If you are going to bend it, you will either need to use a lot of force or heat, both of which would not be wise to do with it in place. However, if you take it off you will need to find a way to rigidly hold it. When bending something like this, I like to clamp a piece of angle iron to it to increase the lever arm. In addition, you can position the clamp so that you control where the bending will take place. Heat can be very helpful but be careful if you haven't used it before, the worst thing that you can do is to overheat it.

Good luck.
Ours was bent pretty badly, much worse than the bend in Dean's roller. It happens while on a mooring and has happened at least twice. While on a mooring, the anchor rests in its roller and if the mooring ball is too high, the mooring line can actually interfere with the anchor. If there's enough motion up there, things can get caught up in the anchor and the anchor will be plastered up against the side of the roller. The steel anchor is stronger than the bronze roller. So the bronze roller loses the battle. And when one of the arms of the roller bends, it bends the pin as well.



Cathy
CD32 Realization, #3
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Raritan Bay
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bottomscraper
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Re: 34 seconds is all it took.

Post by bottomscraper »

Steve Laume wrote:
The first cut took just 32 seconds and 34
seconds for the second cut.
Dulling blade or tired arms?

Rest time or consecutive cuts?

Or about 30 seconds, Steve.
Only enough time between cuts to move it in the vise, add the
possibility of some not so precise timing. I just glanced up at
the clock. Yea about 30 seconds.
Rich Abato
Nordic Tug 34 Tanuki

Previous Owner Of CD36 Mahalo #163

Southern Maine
http://www.sailmahalo.com
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