RE: [bolger] Re: Al vs SS vs HDG
Richard:
I don't know if I mentioned it before, but I have cast bronze, and you are
right about silicon bronze being the easiest to cast. It is also the best
to use in a marine environment. It is very tough, which is good and bad -
good for durability, but hard to machine. All in all, a good choice.
Remember that when molten, SB is much thicker than AL. Make your gates,
sprues, and runners plenty big, and pour hot.
For anyone who is curious about metal casting, Richard has an article coming
up in Duckworks Magazine about his experiences. Look for it in a week or
so.
Chuck
I don't know if I mentioned it before, but I have cast bronze, and you are
right about silicon bronze being the easiest to cast. It is also the best
to use in a marine environment. It is very tough, which is good and bad -
good for durability, but hard to machine. All in all, a good choice.
Remember that when molten, SB is much thicker than AL. Make your gates,
sprues, and runners plenty big, and pour hot.
For anyone who is curious about metal casting, Richard has an article coming
up in Duckworks Magazine about his experiences. Look for it in a week or
so.
Chuck
>
> I can cast bronze, no problem. Only thing, I can cast aluminum from
> scrap. In order to do bronze easily, without flux and adding back
> zinc and whatnot, I need to do silicon bronze. Can get it in ingot
> form around here for $1.65 a pound.... may get me some. Bronze is
> probably about as strong as the steel too...
>
--- In bolger@y..., "Jeff Blunck" <boatbuilding@g...> wrote:
Jamestown #8 1" 9.35/hundred
McFeeley #8 1" 10.05/hundred
www.mcfeelys.com
Bob Chamberland
>to buy
> Try McFeeleys, not sure about their prices but a good reliable place
> stuff on the web.Hi Jeff, about 10% more than Jamestown Distributors.
>
Jamestown #8 1" 9.35/hundred
McFeeley #8 1" 10.05/hundred
www.mcfeelys.com
Bob Chamberland
--- In bolger@y..., richard@s... wrote:
the way of fasteners.
Bob Chamberland
>Hi Richard, try www.Jamestowndistributors.com for anything you need in
> --- In bolger@y..., raymcquin@y... wrote:
> > Richard,
> Could do bronze, but would need bronze screws. OUCH!
>
> Anyone know a good source of silicon bronze screws, for reasonable
> prices?
the way of fasteners.
Bob Chamberland
http://store.yahoo.com/squaredrive/fasteners-screws-flat-head-silicon-bronze
-boat-building-screws---8-flat-head.html
Try McFeeleys, not sure about their prices but a good reliable place to buy
stuff on the web.
Jeff
-boat-building-screws---8-flat-head.html
Try McFeeleys, not sure about their prices but a good reliable place to buy
stuff on the web.
Jeff
----- Original Message -----
From: <richard@...>
To: <bolger@yahoogroups.com>
Sent: Friday, August 17, 2001 12:59 PM
Subject: [bolger] Re: Al vs SS vs HDG
>
> --- In bolger@y..., raymcquin@y... wrote:
> > Richard,
> >
> > Al shows itself when you use SS fasteners to bold Al parts
> together.
> > After a brief exposure to sea water if left untreated and
> undisturbed
> > the two metals become inseperablely joined by corrosion. Strength
> of
> > the Al does not seem to be affected, but you have a heck of a hard
> > time getting them apart for maintenance and repairs. Usually
> > requires drilling out the SS bolts. You can avoid this problem by
> > using neve seze or similar product and peroidicly withdrawing the
> > bolts.
> >
> That might be the trick. SS fasteners with Al parts, using
>http://www.pollardwater.com/emarket/pages/P67702neverseez.aspto keep
> corrosion down to a reasonable level.
>
> Could do bronze, but would need bronze screws. OUCH!
>
> Anyone know a good source of silicon bronze screws, for reasonable
> prices?
>
>
> Bolger rules!!!
> - no cursing, flaming, trolling, spamming, or flogging dead horses
> - pls take "personals" off-list, stay on topic, and punctuate
> - add your comments at the TOP and SIGN your posts, snip all you like
> - To order plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA,
01930, Fax: (978) 282-1349
> - Unsubscribe:bolger-unsubscribe@yahoogroups.com
>
> Your use of Yahoo! Groups is subject tohttp://docs.yahoo.com/info/terms/
>
>
--- In bolger@y..., raymcquin@y... wrote:
http://www.pollardwater.com/emarket/pages/P67702neverseez.aspto keep
corrosion down to a reasonable level.
Could do bronze, but would need bronze screws. OUCH!
Anyone know a good source of silicon bronze screws, for reasonable
prices?
> Richard,together.
>
> Al shows itself when you use SS fasteners to bold Al parts
> After a brief exposure to sea water if left untreated andundisturbed
> the two metals become inseperablely joined by corrosion. Strengthof
> the Al does not seem to be affected, but you have a heck of a hardThat might be the trick. SS fasteners with Al parts, using
> time getting them apart for maintenance and repairs. Usually
> requires drilling out the SS bolts. You can avoid this problem by
> using neve seze or similar product and peroidicly withdrawing the
> bolts.
>
http://www.pollardwater.com/emarket/pages/P67702neverseez.aspto keep
corrosion down to a reasonable level.
Could do bronze, but would need bronze screws. OUCH!
Anyone know a good source of silicon bronze screws, for reasonable
prices?
Good quality silicone bronze falls somewhere between mild steel and
stainless for strength, probably closer to mild steel.
I know there is data around to tell you the actual values, I don't
have it. However when I by fittings they rank mild steel, bronze
then stainless for strength.
stainless for strength, probably closer to mild steel.
I know there is data around to tell you the actual values, I don't
have it. However when I by fittings they rank mild steel, bronze
then stainless for strength.
> Bronze is
> probably about as strong as the steel too...
I wouldn't trust aluminum cast from scrap. You would have no idea what
alloy you'd be creating. You wouldn't know what the galvanic properties
would be.
Phil Smith
alloy you'd be creating. You wouldn't know what the galvanic properties
would be.
Phil Smith
What type of boat? Fresh or salt water?
FWIW I'd suggest bronze, particularly if you can cast it yourself.
I'm no expert, but it shouldn't be much harder than Al to cast, and
not much more expensive either. It's almost as strong as steel, it
resists corrosion better than any of the metals you mentioned, it
machines well, and it looks really nice, particularly if you get a
bit artistic with the patterns. Galvanized is fine as long as the
zinc is still there, a problem with rudder fittings. Stainless is
expensive, nasty to machine, and subject to crevice corrosion below
the waterline. Aluminum is weaker and very vulnerable to corrosion
if you're not careful. I'd dearly love to be able to cast my own
bronze fittings.
FWIW I'd suggest bronze, particularly if you can cast it yourself.
I'm no expert, but it shouldn't be much harder than Al to cast, and
not much more expensive either. It's almost as strong as steel, it
resists corrosion better than any of the metals you mentioned, it
machines well, and it looks really nice, particularly if you get a
bit artistic with the patterns. Galvanized is fine as long as the
zinc is still there, a problem with rudder fittings. Stainless is
expensive, nasty to machine, and subject to crevice corrosion below
the waterline. Aluminum is weaker and very vulnerable to corrosion
if you're not careful. I'd dearly love to be able to cast my own
bronze fittings.
True on all these points, but I believe Rich is going to trailer sail and he
has a foundry for pouring aluminum. As long as the aluminum doesn't come in
contact with dissimilar metals, no problems, use a zinc just in case.
With the advantages you have in using aluminum, I think it comes out ahead
for you Rich.
Jeff
has a foundry for pouring aluminum. As long as the aluminum doesn't come in
contact with dissimilar metals, no problems, use a zinc just in case.
With the advantages you have in using aluminum, I think it comes out ahead
for you Rich.
Jeff
--- In bolger@y..., raymcquin@y... wrote:
scrap. In order to do bronze easily, without flux and adding back
zinc and whatnot, I need to do silicon bronze. Can get it in ingot
form around here for $1.65 a pound.... may get me some. Bronze is
probably about as strong as the steel too...
> Richard,I can cast bronze, no problem. Only thing, I can cast aluminum from
>
> I favor of your three choices hot dipped galvanized steel.
>
>
> You didn't mention bronze as a choice. It is nearly as easy to
> machine as Al. I don't know about casting, that could be a problem
> due to high temps required.
>
> Ray McQuin
>
scrap. In order to do bronze easily, without flux and adding back
zinc and whatnot, I need to do silicon bronze. Can get it in ingot
form around here for $1.65 a pound.... may get me some. Bronze is
probably about as strong as the steel too...
Jeff Blunck wrote:
think you'll have big time corrosion problems with the aluminum unless
you are trailer sailing.
Stainless, as you undoubtedly know, is subject to crevice corrosion, so
it isn't the bullet proof solution below the water line that we all hope
and wish it would be. Above the waterline stainless can look way past
cool as trim. Although I've never welded it myself, the view at last
week's Metal Boat Festival by those who do is that once you've got the
proper equipment (MIG is recommended highly) stainless is no big deal.
For more on metal boats: <http://www.metalboatsociety.com/mbs/index.php>
To get back to Bolger, I plan to begin building a 16' aluminum runabout
of Phil's design next week. I'll try to take photos and share my
experiences.
Phil Smith
>I'd go with either the stainless or the hot dip galvanized mild steel. I
> I'd go aluminum. You have the skills, metal, casting ability, etc. You
> really won't
> have to go real thick. Anything for your new boat would be handled by 1/4"
> aluminum. My rudder is 1/4" and is way...... heavier duty than necessary.
> Use about the same thickness as SS. SS is strong but brittle compared to
> AL. AL can flex a lot before failure, almost tear rather than just snap
> like SS. Mild steel would be somewhere in the middle between the two.
>
> Jeff
>
> ----- Original Message -----
> From: <richard@...>
> To: <bolger@yahoogroups.com>
> Sent: Friday, August 17, 2001 9:39 AM
> Subject: [bolger] Al vs SS vs HDG
>
> > For the various metal parts for new boat, have several options.
> > Specificaly, for rudder shaft and pivot, board pivot mechanism, and
> > tabernacle pivots and plates.
> >
> > 1) Plans call for SS. Could buy MIG kit for welder, and make up parts
> > in SS.
> > - non-experimental
> > - expensive, both SS and MIG stuff high $$
> >
> > 2) Could weld up the parts in mild steel, and have them hot dip
> > galvanized.
> > - easy, know how to weld
> > - cheap
> > - some cruising sailers prefer galv to SS
> >
> > 3) could make some of the parts out of cast and machined aluminum
> > with my newly built
> > - has "koolness factor"
> > - dirt cheap. Have the metal, can cast to shape.
> > - Al not as strong as steel, would have to increase section thickness.
> >
> >
> > Any thoughts?
> >
> >
> >
> >
> >
> > Bolger rules!!!
> > - no cursing, flaming, trolling, spamming, or flogging dead horses
> > - pls take "personals" off-list, stay on topic, and punctuate
> > - add your comments at the TOP and SIGN your posts, snip all you like
> > - To order plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA,
> 01930, Fax: (978) 282-1349
> > - Unsubscribe:bolger-unsubscribe@yahoogroups.com
> >
> > Your use of Yahoo! Groups is subject tohttp://docs.yahoo.com/info/terms/
> >
> >
>
> Bolger rules!!!
> - no cursing, flaming, trolling, spamming, or flogging dead horses
> - pls take "personals" off-list, stay on topic, and punctuate
> - add your comments at the TOP and SIGN your posts, snip all you like
> - To order plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA, 01930, Fax: (978) 282-1349
> - Unsubscribe:bolger-unsubscribe@yahoogroups.com
>
> Your use of Yahoo! Groups is subject tohttp://docs.yahoo.com/info/terms/
think you'll have big time corrosion problems with the aluminum unless
you are trailer sailing.
Stainless, as you undoubtedly know, is subject to crevice corrosion, so
it isn't the bullet proof solution below the water line that we all hope
and wish it would be. Above the waterline stainless can look way past
cool as trim. Although I've never welded it myself, the view at last
week's Metal Boat Festival by those who do is that once you've got the
proper equipment (MIG is recommended highly) stainless is no big deal.
For more on metal boats: <http://www.metalboatsociety.com/mbs/index.php>
To get back to Bolger, I plan to begin building a 16' aluminum runabout
of Phil's design next week. I'll try to take photos and share my
experiences.
Phil Smith
Richard,
I favor of your three choices hot dipped galvanized steel.
In my 30+ yrs on the water I've come to distrust stainless for
critical parts. I'm not a machinist or metallurgist so I won't even
attempt a technical discussion, rather I'll just give my experience.
SS does corrode. Weld joints will rust and become unsightly, but
that is only an esthetic problem. The real problem with SS is
hidden, or crevice corrosion. Without giving any outward sign of
trouble SS will fail without warning. If you can find the pieces
after the failure you will see the break line has a crystallized and
brittle appearance. I have seen instances of SS long exposed to
saltwater turn to swiss cheese, full of holes.
Aluminum is both good and bad. If you are religious about not mixing
the wrong metals Al will behave in a similar fashion to HDG,
announcing it's failure with lots of surface corrosion. Make a bad
choice such as using galvanized fasteners in contact with Al and all
will look fine right up to the moment the Al crumbles in total
failure. One example I heard of was a USCG investigation of the loss
of a small Al passenger boat. At one point the overhead trim inside
had been replaced and the yard had used galvanized screws. The
entire foredeck collapsed on a rough day. Another annoying habit of
Al shows itself when you use SS fasteners to bold Al parts together.
After a brief exposure to sea water if left untreated and undisturbed
the two metals become inseperablely joined by corrosion. Strength of
the Al does not seem to be affected, but you have a heck of a hard
time getting them apart for maintenance and repairs. Usually
requires drilling out the SS bolts. You can avoid this problem by
using neve seze or similar product and peroidicly withdrawing the
bolts.
Corrosion is a given in the marine environment. I just want a
material that is honest, one that tells me by appearance that it is
near failure. HDG does just that. A good galvanize job will give
years of service, except where exposed to friction. If the friction
is constant, once the galv wears off keep the parts lubed and they
will wear a long time. As the galvanizing begins to fail you will
get warnings by the change in appearance, and eventually the
blossoming of good old rust. If the parts are heavy enough they will
continue to give good service long after the rust starts. And best
of all, mild steel rusts from the outside in, with big ugly flakes
and carbuncles that announce the problem.
You didn't mention bronze as a choice. It is nearly as easy to
machine as Al. I don't know about casting, that could be a problem
due to high temps required.
Ray McQuin
I favor of your three choices hot dipped galvanized steel.
In my 30+ yrs on the water I've come to distrust stainless for
critical parts. I'm not a machinist or metallurgist so I won't even
attempt a technical discussion, rather I'll just give my experience.
SS does corrode. Weld joints will rust and become unsightly, but
that is only an esthetic problem. The real problem with SS is
hidden, or crevice corrosion. Without giving any outward sign of
trouble SS will fail without warning. If you can find the pieces
after the failure you will see the break line has a crystallized and
brittle appearance. I have seen instances of SS long exposed to
saltwater turn to swiss cheese, full of holes.
Aluminum is both good and bad. If you are religious about not mixing
the wrong metals Al will behave in a similar fashion to HDG,
announcing it's failure with lots of surface corrosion. Make a bad
choice such as using galvanized fasteners in contact with Al and all
will look fine right up to the moment the Al crumbles in total
failure. One example I heard of was a USCG investigation of the loss
of a small Al passenger boat. At one point the overhead trim inside
had been replaced and the yard had used galvanized screws. The
entire foredeck collapsed on a rough day. Another annoying habit of
Al shows itself when you use SS fasteners to bold Al parts together.
After a brief exposure to sea water if left untreated and undisturbed
the two metals become inseperablely joined by corrosion. Strength of
the Al does not seem to be affected, but you have a heck of a hard
time getting them apart for maintenance and repairs. Usually
requires drilling out the SS bolts. You can avoid this problem by
using neve seze or similar product and peroidicly withdrawing the
bolts.
Corrosion is a given in the marine environment. I just want a
material that is honest, one that tells me by appearance that it is
near failure. HDG does just that. A good galvanize job will give
years of service, except where exposed to friction. If the friction
is constant, once the galv wears off keep the parts lubed and they
will wear a long time. As the galvanizing begins to fail you will
get warnings by the change in appearance, and eventually the
blossoming of good old rust. If the parts are heavy enough they will
continue to give good service long after the rust starts. And best
of all, mild steel rusts from the outside in, with big ugly flakes
and carbuncles that announce the problem.
You didn't mention bronze as a choice. It is nearly as easy to
machine as Al. I don't know about casting, that could be a problem
due to high temps required.
Ray McQuin
--- In bolger@y..., richard@s... wrote:
> For the various metal parts for new boat, have several options.
> Specificaly, for rudder shaft and pivot, board pivot mechanism, and
> tabernacle pivots and plates.
>
> 1) Plans call for SS. Could buy MIG kit for welder, and make up
parts
> in SS.
> - non-experimental
> - expensive, both SS and MIG stuff high $$
>
> 2) Could weld up the parts in mild steel, and have them hot dip
> galvanized.
> - easy, know how to weld
> - cheap
> - some cruising sailers prefer galv to SS
>
> 3) could make some of the parts out of cast and machined aluminum
> with my newly built
> - has "koolness factor"
> - dirt cheap. Have the metal, can cast to shape.
> - Al not as strong as steel, would have to increase section
thickness.
>
>
> Any thoughts?
I'd go aluminum. You have the skills, metal, casting ability, etc. You
really won't
have to go real thick. Anything for your new boat would be handled by 1/4"
aluminum. My rudder is 1/4" and is way...... heavier duty than necessary.
Use about the same thickness as SS. SS is strong but brittle compared to
AL. AL can flex a lot before failure, almost tear rather than just snap
like SS. Mild steel would be somewhere in the middle between the two.
Jeff
really won't
have to go real thick. Anything for your new boat would be handled by 1/4"
aluminum. My rudder is 1/4" and is way...... heavier duty than necessary.
Use about the same thickness as SS. SS is strong but brittle compared to
AL. AL can flex a lot before failure, almost tear rather than just snap
like SS. Mild steel would be somewhere in the middle between the two.
Jeff
----- Original Message -----
From: <richard@...>
To: <bolger@yahoogroups.com>
Sent: Friday, August 17, 2001 9:39 AM
Subject: [bolger] Al vs SS vs HDG
> For the various metal parts for new boat, have several options.
> Specificaly, for rudder shaft and pivot, board pivot mechanism, and
> tabernacle pivots and plates.
>
> 1) Plans call for SS. Could buy MIG kit for welder, and make up parts
> in SS.
> - non-experimental
> - expensive, both SS and MIG stuff high $$
>
> 2) Could weld up the parts in mild steel, and have them hot dip
> galvanized.
> - easy, know how to weld
> - cheap
> - some cruising sailers prefer galv to SS
>
> 3) could make some of the parts out of cast and machined aluminum
> with my newly built
> - has "koolness factor"
> - dirt cheap. Have the metal, can cast to shape.
> - Al not as strong as steel, would have to increase section thickness.
>
>
> Any thoughts?
>
>
>
>
>
> Bolger rules!!!
> - no cursing, flaming, trolling, spamming, or flogging dead horses
> - pls take "personals" off-list, stay on topic, and punctuate
> - add your comments at the TOP and SIGN your posts, snip all you like
> - To order plans: Mr. Philip C. Bolger, P.O. Box 1209, Gloucester, MA,
01930, Fax: (978) 282-1349
> - Unsubscribe:bolger-unsubscribe@yahoogroups.com
>
> Your use of Yahoo! Groups is subject tohttp://docs.yahoo.com/info/terms/
>
>
For the various metal parts for new boat, have several options.
Specificaly, for rudder shaft and pivot, board pivot mechanism, and
tabernacle pivots and plates.
1) Plans call for SS. Could buy MIG kit for welder, and make up parts
in SS.
- non-experimental
- expensive, both SS and MIG stuff high $$
2) Could weld up the parts in mild steel, and have them hot dip
galvanized.
- easy, know how to weld
- cheap
- some cruising sailers prefer galv to SS
3) could make some of the parts out of cast and machined aluminum
with my newly built
- has "koolness factor"
- dirt cheap. Have the metal, can cast to shape.
- Al not as strong as steel, would have to increase section thickness.
Any thoughts?
Specificaly, for rudder shaft and pivot, board pivot mechanism, and
tabernacle pivots and plates.
1) Plans call for SS. Could buy MIG kit for welder, and make up parts
in SS.
- non-experimental
- expensive, both SS and MIG stuff high $$
2) Could weld up the parts in mild steel, and have them hot dip
galvanized.
- easy, know how to weld
- cheap
- some cruising sailers prefer galv to SS
3) could make some of the parts out of cast and machined aluminum
with my newly built
- has "koolness factor"
- dirt cheap. Have the metal, can cast to shape.
- Al not as strong as steel, would have to increase section thickness.
Any thoughts?