ALuminum bolts

Floyd M

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I am looking for a source for aluminum nuts and bolts. Specifically I am looking for new bolts to re-attach my upper rub rail housing once my painting is done on the 21' SS. Thanks in advance for the info.

Keith
 

Andy in NY

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Re: ALuminum bolts

I think aluminum wouldnt be strong enough. i would use aluminum rivets or ss bolts.
 

Floyd M

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Re: ALuminum bolts

I took a bolt I removed to a local fastener place and they said they thought it was aluminum. I don't know how to tell. It is not magnetic but ss bolts aren't really either. Any ideas? How are your rails attached?

Keith
 

Andy in NY

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Re: ALuminum bolts

I took a bolt I removed to a local fastener place and they said they thought it was aluminum. I don't know how to tell. It is not magnetic but ss bolts aren't really either. Any ideas? How are your rails attached?

Keith

mine are bolts, i would assume ss... i didnt think aluminum would be that common... cant be very strong...
 

Floyd M

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Re: ALuminum bolts

mine are bolts, i would assume ss... i didnt think aluminum would be that common... cant be very strong...

Yeah, I know. It just concerned me that if that is what was on the boat originally, then I should probably go back with that. I will hit another fastener shop today and see if they can tell me if it is aluminim or ss.

Keith
 

Andy in NY

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Re: ALuminum bolts

My question would be why are you so concerned over what it came with it originally? ss would out perform al any day in terms of shear strength.
 

Tim Frank

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Re: ALuminum bolts

Used a lot of aluminum bolts when replacing my transom with no problem.
What size fasteners are you talking about? Anything 1/4" or larger has a fair bit of strength.
Weight should tell you what the material is. Aluminum is about 3x lighter than steel.
Lots of sources of Al fasteners on the net.
Spae-Nauer is one.
 

Rickairmedic

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Re: ALuminum bolts

Keith I have a better question . Why are you replcing them ? I just bagged and tagged mine so I can put them back in when I get to that point . Try Fastenal or Grainger . I ended up getting Rivets at Grainger as I only had to order 250 of them insted of the 500 from Fastenal.


Rick
 

Floyd M

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Re: ALuminum bolts

My question would be why are you so concerned over what it came with it originally? ss would out perform al any day in terms of shear strength.

One reason that I was going to go back with the aluminum (if that is what it is) is to avoid electrolysis issues. I will have this boat in the bay part of the time. I do realize that it is going to be difficult to get much salt water inside the rub rail for that to be an issue but I am a big fan of over-engineering.
Keith
 

Floyd M

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Re: ALuminum bolts

Keith I have a better question . Why are you replcing them ? I just bagged and tagged mine so I can put them back in when I get to that point . Try Fastenal or Grainger . I ended up getting Rivets at Grainger as I only had to order 250 of them insted of the 500 from Fastenal.


Rick



About half of them are mangled, bent, had to cut them to remove them, etc. It sounds like the concensus is to just put in ss bolts and be done with them. I didn't really think about going with rivets because I plan on using the neat little plastic cable clips that were already on the tail of the bolts under the gunnels to hold my wiring, steering, etc. I will check Grainger, my best friend is a regional guy with them.

Keith
 

Andy in NY

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Re: ALuminum bolts

One reason that I was going to go back with the aluminum (if that is what it is) is to avoid electrolysis issues. I will have this boat in the bay part of the time. I do realize that it is going to be difficult to get much salt water inside the rub rail for that to be an issue but I am a big fan of over-engineering.
Keith

stainless steel will do you just fine, there will be no reaction with the aluminum.
 

Rickairmedic

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Re: ALuminum bolts

Keith Stainless or Aluminum bolts should be fine . I wouldnt rivet them back on ( just in case you ever hd to get them back off ) :D. The rivets I ordered were mainly to put in all the extra holes in my hull where a Stupid PO screwed in extra stringers :eek:.


Rick
 

Lightnig

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Re: ALuminum bolts

Yeah, I know. It just concerned me that if that is what was on the boat originally, then I should probably go back with that. I will hit another fastener shop today and see if they can tell me if it is aluminim or ss.

Keith


Easy ways to tell:

compare weight to a steel bolt the same size and length. A SS bolt will weight about the same, and Al one will be 1/3 of the weight.

Hit one of your old ones with a grinder. SS will throw off red sparks, Al - no spark at all.



I very highly doubt those bolts are aluminum though, with over a decade in the steel fab industry, specializing in SS and Al work, along with a couple of years working as a warehouseman for a major bolt supplier/manufacturer, I never once heard of an Al bolt. It would be way too soft and prone to thread stripping it wouldn't be funny.
 

Tim Frank

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Re: ALuminum bolts

Easy ways to tell:

compare weight to a steel bolt the same size and length. A SS bolt will weight about the same, and Al one will be 1/3 of the weight.

Hit one of your old ones with a grinder. SS will throw off red sparks, Al - no spark at all.



I very highly doubt those bolts are aluminum though, with over a decade in the steel fab industry, specializing in SS and Al work, along with a couple of years working as a warehouseman for a major bolt supplier/manufacturer, I never once heard of an Al bolt. It would be way too soft and prone to thread stripping it wouldn't be funny.


You need to get out more.....;)

Disregarding the difference in terminology between bolts and machine screws, there are still many, many, suppliers who can ship you aluminum threaded fasteners right out of stock.
My 1959 tinny has no non-aluminum fasteners at all.Lots of strength, too.

S/S will definitely react with aluminum....especially in a salt water environment.
 

Tim Frank

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Re: ALuminum bolts

Well, I'll be darned, look at this:

http://www.racebolts.com/index.php?main_page=index&cPath=675

Pricey buggers though. almost $2 each for what would be a 5/16" x 1" flathead machine screw...


Cool, they have Titanium bolts too. Almost $6 each for the same size listed above... :eek:

Definitely not cheap.
And of course they aren't always anodised in which case S/S might be better for appearance and if they are seldom wet corrosion is probably not that big a concern. No question too, s/s is stronger.
 

Floyd M

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Re: ALuminum bolts

Sounds like I am hitting the grinder with a bolt tomorrow to see if I get pretty sparks or not. If I can get away with ss I will. I don't get too excited about spending $2 for a bolt/machine screw. The big problem is that I am going on vacation. As my wife said, "you would be happy just taking the next ten days and working on that boat"....... Yup!

Keith
 

lowkee

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Re: ALuminum bolts

I never once heard of an Al[uminum] bolt.

Mercruiser Alpha One transom plates have two alum bolts as the two bottom bolts. They are meant to prevent corrosion and cost a nice $30 for the pair (I had to replace mine).
 
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