Hi all,

I'm builing a cherry mantle for some friends, the floating type, made to be
fastened directly to the wall above the fireplace. There are no sides, so no
support from the floor. It weighs about 25 lbs or so. I had planned to use
French cleats to hang it from the wall, but they just found out from the
builder that the house is built with metal studs, and not wood as we had
expected.
Can you hang that much weight from metal studs, and if so, what sort of
fastening system would be best? There are basically 4 studs along the length
of the mantle.

Thanks,

Bob

On May 9, 8:38 am, "giga" wrote:

I'm builing a cherry mantle for some friends, the floating type, made to be
fastened directly to the wall above the fireplace. There are no sides, so no
support from the floor. It weighs about 25 lbs or so. I had planned to use
French cleats to hang it from the wall, but they just found out from the
builder that the house is built with metal studs, and not wood as we had
expected.
Can you hang that much weight from metal studs, and if so, what sort of
fastening system would be best? There are basically 4 studs along the length
of the mantle.

That shouldn't be a problem - then again, it depends on how much crap
the owners put on the mantle. The weight of their stuff could easily
exceed the weight of the mantel if there's a reasonable size shelf
top.

You should use expanding metal anchors into the studs such as a Molly
anchor or toggle bolt, and you might want to consider making the
french cleat on the wall taller so you could get a couple of fasteners
in each stud. You could also use some construction adhesive, but
that's belt and suspenders and probably not necessary.

R

giga wrote:
Hi all,

I'm builing a cherry mantle for some friends, the floating type, made
to be fastened directly to the wall above the fireplace. There are no
sides, so no support from the floor. It weighs about 25 lbs or so. I
had planned to use French cleats to hang it from the wall, but they
just found out from the builder that the house is built with metal
studs, and not wood as we had expected.
Can you hang that much weight from metal studs,

Sure. You could hang it from just the drywall too.
___________

and if so, what sort
of fastening system would be best?

You could use any sort of expanding fastener or just screws meant for
fastening drywall to metal studs...there is very little "out" force, mostly
it is "down".


--

dadiOH
____________________________

dadiOH's dandies v3.06...
....a help file of info about MP3s, recording from
LP/cassette and tips & tricks on this and that.
Get it at http://mysite.verizon.net/xico

"giga" wrote in message
Hi all,

I'm builing a cherry mantle for some friends, the floating type, made to
be
fastened directly to the wall above the fireplace. There are no sides, so
no
support from the floor. It weighs about 25 lbs or so. I had planned to use
French cleats to hang it from the wall, but they just found out from the
builder that the house is built with metal studs, and not wood as we had
expected.
Can you hang that much weight from metal studs, and if so, what sort of
fastening system would be best? There are basically 4 studs along the
length
of the mantle.

BEWA Mantles end up being the resting place of expensive "objects d'art"
(if not for this resident, perhaps for the next) and because of this fact
you may well be doing yourself a favor to "over engineer" ... you do NOT
want any unpleasant call backs from "friends".

What material is the wall? This information is important to an effective
solution.

Self tapping screws can be used into the metal studs, but, depending upon
the wall material, I would also routinely throw in a few molly bolts in
between the studs for the wall half of the French cleat.

As others have mentioned, and depending again upon the wall material, a bit
of construction adhesive would also add to the "belt and suspenders"
approach, which is certainly justified in this particular situation due to
first above.

--
www.e-woodshop.net
Last update: 3/27/08
KarlC@ (the obvious)

"Swingman" wrote in message
...

"giga" wrote in message
Hi all,

I'm builing a cherry mantle for some friends, the floating type, made to
be
fastened directly to the wall above the fireplace. There are no sides, so
no
support from the floor. It weighs about 25 lbs or so. I had planned to
use
French cleats to hang it from the wall, but they just found out from the
builder that the house is built with metal studs, and not wood as we had
expected.
Can you hang that much weight from metal studs, and if so, what sort of
fastening system would be best? There are basically 4 studs along the
length
of the mantle.

BEWA Mantles end up being the resting place of expensive "objects
d'art"
(if not for this resident, perhaps for the next) and because of this fact
you may well be doing yourself a favor to "over engineer" ... you do NOT
want any unpleasant call backs from "friends".

What material is the wall? This information is important to an effective
solution.

Self tapping screws can be used into the metal studs, but, depending upon
the wall material, I would also routinely throw in a few molly bolts in
between the studs for the wall half of the French cleat.

As others have mentioned, and depending again upon the wall material, a
bit
of construction adhesive would also add to the "belt and suspenders"
approach, which is certainly justified in this particular situation due to
first above.

--
www.e-woodshop.net
Last update: 3/27/08
KarlC@ (the obvious)

what would the adhesive do attaching the cleat to drywall? the paper isn't
very strong, and that's all you're gluing to.

"Swingman" wrote:

BEWA Mantles end up being the resting place of expensive "objects
d'art"
(if not for this resident, perhaps for the next) and because of this
fact
you may well be doing yourself a favor to "over engineer" ... you do
NOT
want any unpleasant call backs from "friends".

What material is the wall? This information is important to an
effective
solution.

Self tapping screws can be used into the metal studs, but, depending
upon
the wall material, I would also routinely throw in a few molly bolts
in
between the studs for the wall half of the French cleat.

If I were doing this job, shear load is not going to be a problem;
however, cantilever loading could be.

As someone suggested, the wider the French Cleat, the better. 6"-8"
would be a good starting point, 12" if there is room.

I would attach this cleat using #14, coarse thread, self tapping, S/S,
flat head, sheet metal screws (At least 2-3 per stud) along with
construction adhesive.

Just you're basic belt and suspenders design approach.

Allow the adhesive to cure 10-14 days before using.

Lew

charlie took a can of maroon spray paint on May 9, 2008 10:15 am and wrote
the following:


"Swingman" wrote in message
...

"giga" wrote in message
Hi all,

I'm builing a cherry mantle for some friends, the floating type, made to
be
fastened directly to the wall above the fireplace. There are no sides,
so
no
support from the floor. It weighs about 25 lbs or so. I had planned to
use
French cleats to hang it from the wall, but they just found out from the
builder that the house is built with metal studs, and not wood as we had
expected.
Can you hang that much weight from metal studs, and if so, what sort of
fastening system would be best? There are basically 4 studs along the
length
of the mantle.

BEWA Mantles end up being the resting place of expensive "objects
d'art"
(if not for this resident, perhaps for the next) and because of this fact
you may well be doing yourself a favor to "over engineer" ... you do NOT
want any unpleasant call backs from "friends".

What material is the wall? This information is important to an effective
solution.

Self tapping screws can be used into the metal studs, but, depending upon
the wall material, I would also routinely throw in a few molly bolts in
between the studs for the wall half of the French cleat.

As others have mentioned, and depending again upon the wall material, a
bit
of construction adhesive would also add to the "belt and suspenders"
approach, which is certainly justified in this particular situation due
to first above.


what would the adhesive do attaching the cleat to drywall? the paper isn't
very strong, and that's all you're gluing to.

That is what I was wondering, if the mantle is thick enough, I would
consider removing some of the drywall, and adding 2by4 cross braces between
the metal studs. Bit of ply or drywall to bring it back to level and then
adding the cleat.
--
Lits Slut #9
Life would be so much easier if we could just look at the source code.

"charlie" wrote

what would the adhesive do attaching the cleat to drywall? the paper isn't
very strong, and that's all you're gluing to.

How do you know the OP is attaching to drywall?

Nonetheless, much of the "fastening" of chair rails, wainscotting paneling,
to drywall is done with at least some construction adhesive. Later down the
road, when trying remove same, you gain a quick understanding as why it is
not a bad idea to include in it in a "belt and suspenders" approach.

--
www.e-woodshop.net
Last update: 3/27/08
KarlC@ (the obvious)

"charlie" wrote:

what would the adhesive do attaching the cleat to drywall? the paper
isn't very strong, and that's all you're gluing to.

The adhesive increases the surface area of the cleat in contact with
the drywall.

The increased surface area reduces the load/square inch on the joint.

Lew

"Lew Hodgett" wrote

If I were doing this job, shear load is not going to be a problem;
however, cantilever loading could be.

Precisely ... and the width of the mantle from front to back is an important
component of this particular force, and, like the wall material, is unknown
at present.

Nothing like trying to offer solutions when most of the important factors
are unknown.

--
www.e-woodshop.net
Last update: 3/27/08
KarlC@ (the obvious)

On May 9, 10:21*am, "Lew Hodgett" wrote:
"Swingman" wrote:
BEWA Mantles end up being the resting place of expensive "objects
d'art"
(if not for this resident, perhaps for the next) and because of this
fact
you may well be doing yourself a favor to "over engineer" ... you do
NOT
want any unpleasant call backs from "friends".

What material is the wall? This information is important to an
effective
solution.

Self tapping screws can be used into the metal studs, but, depending
upon
the wall material, I would also routinely throw in a few molly bolts
in
between the studs for the wall half of the French cleat.

If I were doing this job, shear load is not going to be a problem;
however, cantilever loading could be.

As someone suggested, the wider the French Cleat, the better. 6"-8"
would be a good starting point, 12" if there is room.

I would attach this cleat using #14, coarse thread, self tapping, S/S,
flat head, sheet metal screws (At least 2-3 per stud) along with
construction adhesive.

Just you're basic belt and suspenders design approach.

Allow the adhesive to cure 10-14 days before using.

Lew

It also depends on the gauge of the metal stud. I hang entire rows of
wall cabinets on metal studs with toggles if they're thin gauge studs
and self tapping screws if we're dealing with thick metal... even then
we pre-drill with a 1/16 bit.
The load on cabinets is more shear, and Lew is right about the load
being very different if the shelf protrudes from the wall and creates
a cantilevered load. One brass statue and Swing's caution should be
heeded. ( Or one arm of my ex with a beer in her hand leaning on
it...MUCH more serious than a brass Rodin.)

Toggles. When in doubt, I always use properly installed toggles. The
plastic expanding ones will cut themselves on the inner edge of a
metal stud hole, so use metal ones.
This building doesn't have a bd-ft of wood, to screw into, in it:
http://www.marinervillage.ca/photos.htm
We have installed many kitchens in here and toggles are my friend.

On May 9, 10:40*am, Robatoy wrote:
On May 9, 10:21*am, "Lew Hodgett" wrote:



"Swingman" wrote:
BEWA Mantles end up being the resting place of expensive "objects
d'art"
(if not for this resident, perhaps for the next) and because of this
fact
you may well be doing yourself a favor to "over engineer" ... you do
NOT
want any unpleasant call backs from "friends".

What material is the wall? This information is important to an
effective
solution.

Self tapping screws can be used into the metal studs, but, depending
upon
the wall material, I would also routinely throw in a few molly bolts
in
between the studs for the wall half of the French cleat.

If I were doing this job, shear load is not going to be a problem;
however, cantilever loading could be.

As someone suggested, the wider the French Cleat, the better. 6"-8"
would be a good starting point, 12" if there is room.

I would attach this cleat using #14, coarse thread, self tapping, S/S,
flat head, sheet metal screws (At least 2-3 per stud) along with
construction adhesive.

Just you're basic belt and suspenders design approach.

Allow the adhesive to cure 10-14 days before using.

Lew

It also depends on the gauge of the metal stud. I hang entire rows of
wall cabinets on metal studs with toggles if they're thin gauge studs
and self tapping screws if we're dealing with thick metal... even then
we pre-drill with a 1/16 bit.
The load on cabinets is more shear, and Lew is right about the load
being very different if the shelf protrudes from the wall and creates
a cantilevered load. One brass statue and Swing's caution should be
heeded. ( Or one arm of my ex with a beer in her hand leaning on
it...MUCH more serious than a brass Rodin.)

Toggles. When in doubt, I always use properly installed toggles. The
plastic expanding ones will cut themselves on the inner edge of a
metal stud hole, so use metal ones.
This building doesn't have a bd-ft of wood, to screw into, in it:http://www.marinervillage.ca/photos.htm
We have installed many kitchens in here and toggles are my friend.

(suite 114 is one of our jobs)

"charlie" wrote in message
...



what would the adhesive do attaching the cleat to drywall? the paper isn't
very strong, and that's all you're gluing to.


Have you ever tried to suck the paper off the wall before? ;~)

The strength would be in the huge adhesion area and while not sufficient by
itself would add considerable stability to other fasteners. I have seen
large pictures hung on those removable 3M adhesive hook strips and those do
not cover much area by comparison.

"Robatoy" wrote

Toggles. When in doubt, I always use properly installed toggles. The
plastic expanding ones will cut themselves on the inner edge of a
metal stud hole, so use metal ones.

Interchangeable terminology for a "molly bolt" down here in Tejas ...

--
www.e-woodshop.net
Last update: 3/27/08
KarlC@ (the obvious)

"Lew Hodgett" wrote in message
news:R5ZUj.5$%X1.1@trnddc08...

"Swingman" wrote:

BEWA Mantles end up being the resting place of expensive "objects
d'art"
(if not for this resident, perhaps for the next) and because of this fact
you may well be doing yourself a favor to "over engineer" ... you do NOT
want any unpleasant call backs from "friends".

What material is the wall? This information is important to an effective
solution.

Self tapping screws can be used into the metal studs, but, depending upon
the wall material, I would also routinely throw in a few molly bolts in
between the studs for the wall half of the French cleat.

If I were doing this job, shear load is not going to be a problem;
however, cantilever loading could be.

As someone suggested, the wider the French Cleat, the better. 6"-8" would
be a good starting point, 12" if there is room.

I would attach this cleat using #14, coarse thread, self tapping, S/S,
flat head, sheet metal screws (At least 2-3 per stud) along with
construction adhesive.

Just you're basic belt and suspenders design approach.

Allow the adhesive to cure 10-14 days before using.

Lew



I should have elaborated a bit...

The wall is garden variety drywall.
The mantle itself is 8" deep and about 4" thick. It's done with a torsion
box, so it's not solid cherry, but it sure ain't balsa wood. It's the
cantilever force I'm concerned about. That's a lot of weight hanging as far
as 8" out from the wall, with only 4" of surface area against it. I'm not
sure that adhesive would be much of an aid in this case. The cleat itself is
Lee Valley's aluminium Z-clips
(http://www.leevalley.com/hardware/pa...41308&p=41869),
two sections of 2' each. It's not very wide, but I reckon I could drill
pairs of holes instead of singles in each location, but maybe not #14.


Bob

On May 9, 10:53*am, "Swingman" wrote:
"Robatoy" wrote

Toggles. When in doubt, I always use properly installed toggles. The
plastic expanding ones will cut themselves on the inner edge of a
metal stud hole, so use metal ones.

Interchangeable terminology for a "molly bolt" down here in Tejas ...

The ones I use have two spring-loaded wings that deploy after
insertion.

So whatsitgonna be? A pop and sub or a soda and a hoagy? G

On May 9, 11:00*am, "giga" wrote:
"Lew Hodgett" wrote in message

news:R5ZUj.5$%X1.1@trnddc08...





"Swingman" wrote:

BEWA Mantles end up being the resting place of expensive "objects
d'art"
(if not for this resident, perhaps for the next) and because of this fact
you may well be doing yourself a favor to "over engineer" ... you do NOT
want any unpleasant call backs from "friends".

What material is the wall? This information is important to an effective
solution.

Self tapping screws can be used into the metal studs, but, depending upon
the wall material, I would also routinely throw in a few molly bolts in
between the studs for the wall half of the French cleat.

If I were doing this job, shear load is not going to be a problem;
however, cantilever loading could be.

As someone suggested, the wider the French Cleat, the better. 6"-8" would
be a good starting point, 12" if there is room.

I would attach this cleat using #14, coarse thread, self tapping, S/S,
flat head, sheet metal screws (At least 2-3 per stud) along with
construction adhesive.

Just you're basic belt and suspenders design approach.

Allow the adhesive to cure 10-14 days before using.

Lew

I should have elaborated a bit...

The wall is garden variety drywall.
The mantle itself is 8" deep and about 4" thick. It's done with a torsion
box, so it's not solid cherry, but it sure ain't balsa wood. It's the
cantilever force I'm concerned about. That's a lot of weight hanging as far
as 8" out from the wall, with only 4" of surface area against it. I'm not
sure that adhesive would be much of an aid in this case. The cleat itself is
Lee Valley's aluminium Z-clips
(http://www.leevalley.com/hardware/pa...,41308&p=4...),
two sections of 2' each. It's not very wide, but I reckon I could drill
pairs of holes instead of singles in each location, but maybe not #14.

Bob

I suppose it is a bit late for this idea, but I would have approached
it a little differently.
I would have built a torsion box with a tapered (45-degree) removable
front and screwed the back part of the box directly (and flush) into
the studs, with a long screwdriver, and then re-inserted the front
'panel'.... even before applying the finish....maybe.
Those cleats are going to keep your box away from the wall, aren't
they? Or are you letting them in?

(I'm not trying to belabour a point here, but I do run into these
situations, so I'm keeping an eye on this thread.)

dadiOH wrote:
: giga wrote:

: no support from the floor. It weighs about 25 lbs or so.

: Sure. You could hang it from just the drywall too.

The weight of the mantle is not what you worry about. You need to
estimate the load of a 300 lb 6'6" guy leaning on it with his
fore-arms. Or maybe two such guys. Or, worst case, someone standing
on it to put the star on the top of the Christmas tree. If it looks
big and solid and it's attached to the wall, people will assume that
it can take load like a step-stool.

True story: A guy was making some pull-down stairs for a hay-loft, and
asked my father to check the design. My father recommended beefing up
a cross bar, and the guy asked why, since it didn't have any load on
it. My father explained that sooner or later some guy was going to
use it as a chin-up bar.

The day after it was installed, the guy was showing it to his
neighbor, a big football player type. As soon as he saw the bar he
jumped up and chinned himself on it.

--- Chip

"Robatoy" wrote

So whatsitgonna be? A pop and sub or a soda and a hoagy? G

An R'erC and a moonpie, thanks!




--
www.e-woodshop.net
Last update: 3/27/08
KarlC@ (the obvious)

"Robatoy" wrote

Toggles. When in doubt, I always use properly installed toggles. The
plastic expanding ones will cut themselves on the inner edge of a
metal stud hole, so use metal ones.

"Swingman" wrote:

Interchangeable terminology for a "molly bolt" down here in Tejas
...

Guys, give me a large enough cleat and a notched trowel to apply the
adhesive, and the ONLY purpose of the fasteners is to hold the cleat
snug while the adhesive cures.

After the adhesive cures, remove the fasteners and plug the holes if
you like.

There purpose has been served.

BTW, SFWIW, major difference between Toggle and Molly bolts in my part
of the country.


Lew

"Lew Hodgett" wrote

BTW, SFWIW, major difference between Toggle and Molly bolts in my part
of the country.

That I may well have to stand corrected is a distinct possibility, due to my
coonass upbringing where the translation doesn't always coincide with the
Anglais.

The ones I'm talking about are the ones with the "wings on springs" that pop
out after being poked through a pre-drilled hole. They are by far the
strongest "wall anchors".

Reflecting on it, they are more "toggle" like in their description, so
Boudreau probably don't know what da hell he talking about, him.

--
www.e-woodshop.net
Last update: 3/27/08
KarlC@ (the obvious)

"Swingman", the Registered CoonAss, wrote:

The ones I'm talking about are the ones with the "wings on springs"
that pop
out after being poked through a pre-drilled hole. They are by far
the
strongest "wall anchors".

Those are "toggle bolts".

I try to avoid them at all costs.

They require a large clearance hole to install, and are a single use
item.

"Molly Bolts" have a stamped steel cage around the self contained
screw that expands and grabs the back side of the drywall when snugged
up.

Lighter duty than toggle bolts but very useful for hanging full length
draw drapes for example, and they are reusuable.

Lew

"giga" wrote:



I should have elaborated a bit...

The wall is garden variety drywall.
The mantle itself is 8" deep and about 4" thick. It's done with a
torsion box, so it's not solid cherry, but it sure ain't balsa wood.
It's the cantilever force I'm concerned about. That's a lot of
weight hanging as far as 8" out from the wall, with only 4" of
surface area against it. I'm not sure that adhesive would be much of
an aid in this case. The cleat itself is Lee Valley's aluminium
Z-clips two sections of 2' each. It's not very wide, but I reckon I
could drill pairs of holes instead of singles in each location, but
maybe not #14.

I'd forget the Lee Valley stuff and build an exposed cleat at least 8"
high with a reverse 45 on top which then gets glued to the dry wall.

Using a large cleat will spread the load.

Probably require some time back on the drawing board, but worth it.

Lew

Chip Buchholtz wrote:
dadiOH wrote:
giga wrote:

no support from the floor. It weighs about 25 lbs or so.

Sure. You could hang it from just the drywall too.

The weight of the mantle is not what you worry about. You need to
estimate the load of a 300 lb 6'6" guy leaning on it with his
fore-arms. Or maybe two such guys. Or, worst case, someone
standing
on it to put the star on the top of the Christmas tree. If it looks
big and solid and it's attached to the wall, people will assume that
it can take load like a step-stool.

True story: A guy was making some pull-down stairs for a hay-loft,
and
asked my father to check the design. My father recommended beefing
up
a cross bar, and the guy asked why, since it didn't have any load on
it. My father explained that sooner or later some guy was going to
use it as a chin-up bar.

The day after it was installed, the guy was showing it to his
neighbor, a big football player type. As soon as he saw the bar he
jumped up and chinned himself on it.

When you hang doors, always assume such a use.


--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

On May 9, 11:20*am, "Swingman" wrote:
"Robatoy" wrote

So whatsitgonna be? A pop and sub or a soda and a hoagy? G

An R'erC and a moonpie, thanks!

Moonpie.... errrmmm.... maybe I shouldn't elaborate. ( but it had to
do with da girlfriend, walking on the beach at night.. then she'd
check the laces on her sneakers....alas I said too much
already.......)

Molly Bolts, eh? Yes, Those flare out like a star and are some tough.
One use only. The toggles, you can take out the screw and have the
wing part fall down and re-insert the a new toggle.
Lew is right about them being a sloppy hole, but used in conjunction
with a french cleat, they are very solid.
Long cleats have the problem of walls being not-flat.

r

"Robatoy" wrote in message
...
On May 9, 10:53 am, "Swingman" wrote:
"Robatoy" wrote

Toggles. When in doubt, I always use properly installed toggles. The
plastic expanding ones will cut themselves on the inner edge of a
metal stud hole, so use metal ones.

Interchangeable terminology for a "molly bolt" down here in Tejas ...

The ones I use have two spring-loaded wings that deploy after
insertion.

So whatsitgonna be? A pop and sub or a soda and a hoagy? G


Down here it usta be Sody Water.

On May 9, 12:02 pm, "Lew Hodgett" wrote:
"giga" wrote:
I should have elaborated a bit...

The wall is garden variety drywall.
The mantle itself is 8" deep and about 4" thick. It's done with a
torsion box, so it's not solid cherry, but it sure ain't balsa wood.
It's the cantilever force I'm concerned about. That's a lot of
weight hanging as far as 8" out from the wall, with only 4" of
surface area against it. I'm not sure that adhesive would be much of
an aid in this case. The cleat itself is Lee Valley's aluminium
Z-clips two sections of 2' each. It's not very wide, but I reckon I
could drill pairs of holes instead of singles in each location, but
maybe not #14.

I'd forget the Lee Valley stuff and build an exposed cleat at least 8"
high with a reverse 45 on top which then gets glued to the dry wall.

Using a large cleat will spread the load.

Probably require some time back on the drawing board, but worth it.

Lew

I would have loved to have done that, and was going to to begin with,
but they decided they really didn't want the mantle to be thicker than
4", and swore up and down they would never put anything heavy on it.
They were also sure the studs were wood, until I insisted they verify
with the builder.


Oh well, maybe I'll suggest they hang it from the cathedral ceiling
with very long wires....

Bob

On May 9, 7:15*am, "charlie"
wrote:
what would the adhesive do attaching the cleat to drywall? the paper isn't
very strong, and that's all you're gluing to.

One important advantage is that a fixed item doesn't
pry up its fasteners one at a time as it flexes. I've
used construction adhesive and masking paper to
make a tight conformation of a cleat to a wall: tape up
the masking paper to protect the wall, put down a bead
of glue on the cleat, affix the cleat over the paper,
then trim any paper away when it's dry. It's easier
than coping an oak board to a plaster wall...
With all the gaps filled, the board and wall move together.

Wood around screw threads can crumble with shock: glue can be
strong enough (a mantle cleat can have square feet of
glue area) to hold normal loads, then when a shock comes
along the screws get only a momentary load. The screws
could work loose under sustained load, we all see this
in doors with poorly mortised hinges. OK, it is a small
effect, but wood DOES give way under sustained stress
that a strong metal screw is likely to apply.


It's advantageous, where possible, to use large contact areas
where wood is stressed; a lap joint with dowels holds more
shear than the same joint with screws, because the dowel
surface area in contact with the wood is much larger than the screw
cross-section.

wrote in message

I would have loved to have done that, and was going to to begin with,
but they decided they really didn't want the mantle to be thicker than
4", and swore up and down they would never put anything heavy on it.
They were also sure the studs were wood, until I insisted they verify
with the builder.


Oh well, maybe I'll suggest they hang it from the cathedral ceiling
with very long wires....

If you use the French cleat(s) with as many screws into the studs as you can
get with self tapping screws, and also fastened to the sheetrock with
"toggle bolts" in between the metal studs, AND, if possible, some
construction adhesive to bond the back of the mantel to the drywall, you
should be in pretty good shape.

Even without the construction adhesive, and providing all your screws prove
to have a solid hold, my estimation from your description thus far is that
you'll be just fine.

--
www.e-woodshop.net
Last update: 3/27/08
KarlC@ (the obvious)

wrote:

I would have loved to have done that, and was going to to begin
with,
but they decided they really didn't want the mantle to be thicker
than
4", and swore up and down they would never put anything heavy on it.
They were also sure the studs were wood, until I insisted they
verify
with the builder.


Oh well, maybe I'll suggest they hang it from the cathedral ceiling
with very long wires....

Will the client buy into the idea of the cleat being an architectural
item that serves as background for the mantle since it would be larger
than the mantle?

Lew

On May 9, 4:08 pm, "Lew Hodgett" wrote:
wrote:
I would have loved to have done that, and was going to to begin
with,
but they decided they really didn't want the mantle to be thicker
than
4", and swore up and down they would never put anything heavy on it.
They were also sure the studs were wood, until I insisted they
verify
with the builder.

Oh well, maybe I'll suggest they hang it from the cathedral ceiling
with very long wires....

Will the client buy into the idea of the cleat being an architectural
item that serves as background for the mantle since it would be larger
than the mantle?

Lew

Well, that's exactly what I was thinking, and I think they would. A
nice, matching cleat visible behind and below the mantle itself could
actually look OK and be a pretty good solution. The back of the thing
is recessed 1/4" to accommodate the Z-clips, as is the back edge of
the bottom, but I could fairly easily build up the back edges of the
top and sides by another 1/2" to shroud the cleat, maybe in walnut or
some other accent wood.

This can definitely be saved...I think...

Bob

wrote:


This can definitely be saved...I think...

Have fun G

Lew

On May 9, 5:00*pm, "Lew Hodgett" wrote:
wrote:
This can definitely be saved...I think...

Have fun G

Lew

I built a kitchen table, per request of a dear client of mine, which
protruded 8 feet from the wall of her kitchen, no support, and 28"
wide. It became a torsion box, Baltic birch and WEST epoxy. The anchor
inside the wall was a simple doubling up of baltic birch.
*I* figured, that if that stuff was good enough for Mosquito bomber,
it was okay for my application.

When *I* sat on the end of that table with my ample weight, the
downward deflection was somewhere between 3/8 and 1/2 inches. It was
only 3" thick.

I luuuuuv torsion boxes.

"Robatoy" wrote:


I luuuuuv torsion boxes.

Moment of Inertia (I) = (B)(H^3)/12 + 1/2(A)(D^2)

Moment of Inertia is your friend and easy to increase with a torison
box.

Lew

On May 9, 8:43*pm, "Lew Hodgett" wrote:
"Robatoy" wrote:
I luuuuuv torsion boxes.

Moment of Inertia (I) *= (B)(H^3)/12 + 1/2(A)(D^2)

Moment of Inertia is your friend and easy to increase with a torison
box.

Lew

I used 1/2" BB all around, but I could have used 1/8" for the skins.

"Robatoy" wrote:

I used 1/2" BB all around, but I could have used 1/8" for the skins.

There is a reason they're called "door skins".

If you can read a newspaper thru them, they are probably thick
enoughG.

Lew

"Lew Hodgett" wrote in message
news:La2Vj.314$T1.281@trnddc01...

wrote:

I would have loved to have done that, and was going to to begin with,
but they decided they really didn't want the mantle to be thicker than
4", and swore up and down they would never put anything heavy on it.
They were also sure the studs were wood, until I insisted they verify
with the builder.


Oh well, maybe I'll suggest they hang it from the cathedral ceiling
with very long wires....

Will the client buy into the idea of the cleat being an architectural item
that serves as background for the mantle since it would be larger than the
mantle?

Lew

Well, as an update for them what's interested, I'm going to attach a wide
cleat to the wall, glued, screwed, toggled, etc and hang the mantle on that.
The twist is that the visible edges of the cleat will be bevelled, and the
cleat will be painted same colour as the wall. That way, rather than looking
like a piece of wood fastened to the wall, it will look more like wall
feature. It will aslo be much easier to hide the bolt and screw heads, as
they will be countersunk, filled, and painted.

Bob