I sprayed LPS-3, which dries to a waxy film, into the boxes of lag
screws, and I predrill oak and pressure-treated SYP for the shank and
threads, somewhat undersized since the fasteners need to withstand an
estimated half ton of snow and ice on the roof. . AFAICT the hard wood
scours off some of the zinc, so wax doesn't really have a chance.
I stopped waxing furniture screws because it interferes with staining.
I spent this morning sanding off a misguided amateur puttying and
staining job in the club's bathroom. On the way home I raided HD's
rack of unpretty PT 4x4's at 70% off. The firewood it will support
doesn't care what it looks like.
Are you using tapered drillbits? If you're scouring the galv off it
on the way in, the hardware won't last in PT, anyway. LPS-3 should be
Ewwwwwwwwwwwww! Wood shouldn't be stained. Use a clearcoat, fer
Crom's sake! </purist> But if you must stain, finish the wood first,
then drill and assemble. Pieces of carpet on your drillpress are
friendly to prefinished furniture components.
Funny, that. ;)
The most powerful factors in the world are clear
ideas in the minds of energetic men of good will.
Which means they can NOT be T6. 1XXX, 3XXX and 5XXX are not heat
treatable. 5XXX is a Magnesium alloy and is weldable. 1XXX are "pure"
aluminum, 3XXX are Manganese alloys.
The 6XXX are heat treatable, weladable magnesium silicone alloys - the
silicone allows the heat treating.(forms magnesium silicide wich is
"disolved" into the metal by solution heat treating.
On Sun, 09 Feb 2014 21:34:50 -0500, firstname.lastname@example.org wrote:
A substantial amount of the high performance sailboat masts and spars
are 6061, usually marked "T6" :-) I've no idea why as 5052 and 6061
are roughly the same strength so I assume it has something to do with
availability or cost.
My guess is strength after welding and extrudability. 6061 will
naturally reharden after welding, though not to its pre-welded T6
condition. 5052 will remain more or less annealed near any welds.
Perhaps. There is usually a certain amount of welding on masts and
spars, if only to attach the end fittings, and I suspect that it is
unlikely that every shop has a forty or fifty foot heat treating oven
None of my spars have ever been welded.
The spreader fittings, mast head crane. etc were always bolted.
Although there are some specialty masts that are tapered and thus welded.
No, I suspect the reason for 6061-T6 is because the spars are almost
And the stable temper of T6...
And the difference in tensile strength!
5052 yields at 28k
6061 yields at 40k
GENERAL ALUMINUM INFORMATION
This grade is commercially pure aluminum. It is soft and ductile and has
excellent workability. It is ideal for applications involving intricate
forming because it work hardens more slowly than other alloys. It is the
most weldable of aluminum alloys, by any method. It is non
heat-treatable. It has excellent resistance to corrosion and is widely
used in the chemical and food processing industries. It responds well to
decorative finishes which make it suitable for giftware.
This is the most free-machining of the common aluminum alloys. It also
has excellent mechanical properties. Thus, it is widely used for
automatic screw machine products in parts requiring extensive machining.
2014 & 2017
The 2017 alloy combines excellent machinability and high strength with
the result that it is one of the most widely used alloys for automatic
screw machine work. It is a tough, ductile alloy suitable for heavy-duty
structural parts. Its strength is slightly less than that of 2014.
This is one of the best known of the high strength aluminum alloys. With
its high strength and excellent fatigue resistance, it is used to
advantage on structures and parts where good strength-to-weight ratio is
desired. It is readily machined to a high finish. It is readily formed
in the annealed condition and may be subsequently heat treated. Arc or
gas welding is generally not recommended, although this alloy may be
spot, seam or flash welded. Since corrosion resistance is relatively
low, 2024 is commonly used with an anodized finish or in clad form
(?Alclad?) with a thin surface layer of high purity aluminum.
Applications: aircraft structural components, aircraft fittings,
hardware, truck wheels and parts for the transportation industry.
This is the most widely used of all aluminum alloys. It is essentially
commercially pure aluminum with the addition of manganese which
increases the strength some 20% over the 1100 grade. Thus, it has all
the excellent characteristics of 1100 with higher strength. It has
excellent corrosion resistance. It has excellent workability and it may
be deep drawn or spun, welded or brazed. It is non heat treatable.
Applications: cooking utensils, decorative trim, awnings, siding,
storage tanks, chemical equipment.
This alloy is generally considered to be an improved version of 3003. It
has the same general mechanical properties as 3003 but appears to stand
up better in actual service. It is readily workable. It can be deep
drawn or spun, welded or brazed. It has excellent corrosion resistance.
It is non heat-treatable. It is well suited for anodizing and has less
tendency to streak or discolor. Applications same as 3003.
This is the highest strength alloy of the more common non heat-treatable
grades. Fatigue strength is higher than most aluminum alloys.In addition
this grade has particularly good resistance to marine atmosphere and
salt water corrosion. It has excellent workability. It may be drawn or
formed into intricate shapes and its slightly greater strength in the
annealed condition minimizes tearing that occurs in 1100 and 3003.
Applications: Used in a wide variety of applications from aircraft
components to home appliances, marine and transportation industry parts,
heavy duty cooking utensils and equipment for bulk processing of food.
5083 & 5086
For many years there has been a need for aluminum sheet and plate alloys
that would offer, for high strength welded applications, several
distinct benefits over such alloys as 5052 and 6061. Some of the
benefits fabricators have been seeking are greater design efficiency,
better welding characteristics, good forming properties, excellent
resistance to corrosion and the same economy as in other non
heat-treatable alloys. Metallurgical research has developed 5083 and
5086 as superior weldable alloys which fill these needs. Both alloys
have virtually the same characteristics with 5083 having slightly higher
mechanical properties due to the increased manganese content over 5086.
Applications: unfired pressure vessels, missile containers, heavy-duty
truck and trailer assemblies, boat hulls and superstructures.
This is the least expensive and most versatile of the heat-treatable
aluminum alloys. It has most of the good qualities of aluminum. It
offers a range of good mechanical properties and good corrosion
resistance. It can be fabricated by most of the commonly used
techniques. In the annealed condition it has good workability. In the T4
condition fairly severe forming operations may be accomplished. The full
T6 properties may be obtained by artificial aging. It is welded by all
methods and can be furnace brazed. It is available in the clad form
(?Alclad?) with a thin surface layer of high purity aluminum to improve
both appearance and corrosion resistance. Applications: This grade is
used for a wide variety of products and applications from truck bodies
and frames to screw machine parts and structural components. 6061 is
used where appearance and better corrosion resistance with good strength
This grade is commonly referred to as the architectural alloy. It was
developed as an extrusion alloy with relatively high tensile properties,
excellent finishing characteristics and a high degree of resistance to
corrosion. This alloy is most often found in various interior and
exterior architectural applications, such as windows, doors, store
fronts and assorted trim items. It is the alloy best suited for
anodizing applications - either plain or in a variety of colors.
This is one of the highest strength aluminum alloys available. Its
strength-to weight ratio is excellent and it is ideally used for highly
stressed parts. It may be formed in the annealed condition and
subsequently heat treated. Spot or flash welding can be used, although
arc and gas welding are not recommended. It is available in the clad
(?Alclad?) form to improve the corrosion resistance with the over-all
high strength being only moderately affected. Applications: Used where
highest strength is needed.
ALUMINUM TEMPER DESIGNATIONS
Temper designations of wrought aluminum alloys consist of suffixes to
the numeric alloy designations. For example, in 3003-H14, 3003 denotes
the alloy and ?H14? denotes the temper, or degree of hardness. The
temper designation also reveals the method by which the hardness was
obtained. Temper designations differ between non heat-treatable alloys
and heat-treatable alloys. and their meanings are given below:
Non Heat-Treatable Alloys
The letter ?H? is always followed by 2 or 3 digits. The first digit
indicates the particular method used to obtain the temper. as follows:
? Hl means strain hardened only.
? H2 means strain hardened, then partially annealed.
? H3 means strain hardened, then stabilized.
The temper is indicated by the second digit as follows:
2 1/4 hard
4 I/2 hard
6 3/4 hard
8 full hard
9 extra hard
Added digits indicate modification of standard practice.
-F As fabricated
-T Heat treated
The letter ?T? is always followed by one or more digits. These digits
indicate the method used to produce the stable tempers, as follows:
-T3 Solution heat treated, then cold worked.
-T351 Solution heat treated, stress-relieved stretched, then cold
-T36 Solution heat treated, then cold worked (controlled).
-T4 Solution heat treated, then naturally aged.
-T451 Solution heat treated, then stress relieved stretched.
-T5 Artificially aged only.
-T6 Solution heat treated, then artificially aged.
-T61 Solution heat treated (boiling water quench), then
-T651 Solution heat treated, stress-relieved stretched, then
artificially aged (precipitation heat treatment).
-T652 Solution heat treated, stress relieved by compression. then
-T7 Solution heat treated, then stabilized.
-T8 Solution heat treated, cold worked, then artificially aged.
-T81 Solution heat treated, cold worked (controlled), then
-T851 Solution heat treated, cold worked, stress-relieved
stretched, then artificially aged.
-T9 Solution heat treated, artificially aged, then cold worked.
-T10 Artificially aged, then cold worked.
Added digits indicate modification of standard practice.
Not really "specialty". Quite a few masts on, say 40+ foot boats are
tapered by cutting and welding. My last boat, for example. 42 ft. deck
stepped with about 25% of the top tapered. Partially I think to make
more room for the jib furler. The spreader brackets were also welded
to the mast, as was a bracket for the steaming light.
Okay Ned, I have a question...I don't know how far back your bad old days were
but in the 50's when I needed some aluminum welding done I always had it done by
Heliarc, as if the gas welding flux hadn't been developed yet...I really don't
know this for sure. But now that I am retired my 'To Do' list has grown to a
couple of life times long and I can't get everything crammed in. I have I think
at least 3 gas welding outfits, the regular industrial, a mid sized venturi air
type and a little Map Gas-Oxygen affair. I haven't gotten around to teaching
myself how to weld aluminum. I see the flux coated gas rod and this is my
question....could this be an easy way to get started on this? Or could you
recommend another starting point? I don't want to bother with getting into the
Mig welding area.
I learned to gas weld aluminum in 1951 and it was a bitch. My
suggestion is to arc weld anything thick enough and buy a TIG for the
The problem with gas welding, and to some extent TIG welding aluminum
is that the metal doesn't change color when heated. You are heating
the parent metal, waiting for a puddle to form and suddenly the whole
thing falls on the ground.
The technique is to keep poking the spot where you intend the puddle
to form with the filler rod. If all goes well you will poke and a bit
of rod will melt off and there's your puddle.
But it is so much easier to just use the TIG or even a plain old arc
welder (with aluminum rods :-).
As an aside, not all aluminum can be welded.
I got shown how to weld aluminium with gas back in about 1985 by a
welding instructor, he wasn't a real welder but taught the course and
could passably gas weld aluminium. I had already taught myself to OA
weld so was good at steel and I noticed that there is a subtle change in
the surface appearance of the aluminium before it drops on the floor and
that is when to add the filler to keep the pool under control. After
about 10 minutes I was welding Al better than the instructor. Never had
any issues with glare either, the flux just seemed to go water clear and
wet the surface when near welding temp and I was fine with the standard
gas welding filters, maybe the flux in the UK is different. Not gas
welded Al for maybe 20 years now as have had TIG to use for Al but don't
weld Al that often anyway.
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