My wife kept reminding me that I'd promised to build her a blanket chest
- she claims 20 years ago :-). So I've started on one. I didn't want to
spend a lot of design/rejected/design time so I picked a plan out of a
Wood magazine and she approved it.
It's a frame and panel with the legs serving as frame edges. It uses
stub tenons (3/8" thick, 3/8" deep, 2.5" and 4" wide). After I got
everything all cut it occurred to me that they were using the plywood
panels as structural members. Well, I'm not using plywood so my oak
panels are free floating.
So now I'm worrying if the stub tenons are strong enough. I've thought
of a few possible fixes. I could glue the edge of the panels that go
into the legs along the edge and across the 1st inch of the top and
bottom. That would add some strength.
I could add a couple of dowels to the rail/leg joints but they'd have to
be offset because the grooves in the legs almost meet now. For that
reason there's no room for floating tenons.
There's also a 2" wide ledge glued to the top edges of the rails and legs
so that does add a little strength.
Or I could admit defeat and go buy some oak plywood and save all my
nicely resawn quartersawn 3/8" panels for some future projects.
Am I being overly cautious? I don't expect the chest to take a lot of
racking or rough handling. Maybe it'd be fine just the way it is.
--
Intelligence is an experiment that failed - G. B. Shaw
Can you modify the dimensions just slightly so the tenons could be just a
bit longer and then have them meet inside the mortice in a miter so the
tenons are glued to each other inside the mortice?
Russ
"Larry Blanchard" <[email protected]> wrote in message
news:[email protected]...
> My wife kept reminding me that I'd promised to build her a blanket chest
> - she claims 20 years ago :-). So I've started on one. I didn't want to
> spend a lot of design/rejected/design time so I picked a plan out of a
> Wood magazine and she approved it.
>
> It's a frame and panel with the legs serving as frame edges. It uses
> stub tenons (3/8" thick, 3/8" deep, 2.5" and 4" wide). After I got
> everything all cut it occurred to me that they were using the plywood
> panels as structural members. Well, I'm not using plywood so my oak
> panels are free floating.
>
> So now I'm worrying if the stub tenons are strong enough. I've thought
> of a few possible fixes. I could glue the edge of the panels that go
> into the legs along the edge and across the 1st inch of the top and
> bottom. That would add some strength.
>
> I could add a couple of dowels to the rail/leg joints but they'd have to
> be offset because the grooves in the legs almost meet now. For that
> reason there's no room for floating tenons.
>
> There's also a 2" wide ledge glued to the top edges of the rails and legs
> so that does add a little strength.
>
> Or I could admit defeat and go buy some oak plywood and save all my
> nicely resawn quartersawn 3/8" panels for some future projects.
>
> Am I being overly cautious? I don't expect the chest to take a lot of
> racking or rough handling. Maybe it'd be fine just the way it is.
>
>
>
> --
> Intelligence is an experiment that failed - G. B. Shaw
On 5/18/2009 3:57 PM CW spake thus:
> "Lew Hodgett" <[email protected]> wrote in message
> news:[email protected]...
>>
>> 1) Use a stronger adhesive than the plans specify, probably epoxy.
>>
> Yellow glue is stronger than wood. A stronger glue wouldn't make any
> difference.
True that. In the copy of /Fine Woodworking/'s "Proven Shop Tips" I'm
rereading, editor Bruce Hoadley says in a note that "most glue joints
are far stronger than they need to be".
--
Found--the gene that causes belief in genetic determinism
On Mon, 18 May 2009 11:17:27 -0500, Larry Blanchard
<[email protected]> wrote:
><<<<<<<<<< SNIP >>>>>>>>>>>>>>>>>>
>
>So now I'm worrying if the stub tenons are strong enough. I've thought
>of a few possible fixes. I could glue the edge of the panels that go
>into the legs along the edge and across the 1st inch of the top and
>bottom. That would add some strength.
>
>>>>>>>>>>>> SNAP <<<<<<<<<<<<<<<<<<
Had the samew issue beginning of this year with, amazingly enough, a
blanket chest. My solution was to inlay 1 inch wide by 6 inches long
oak strips across the inside of the tenon joints. The inlays were made
with a router and templates to create the cutouts and strips to fit. I
could have done butterfly inlays (added strength due to mechanical
locking) but time was running short. The only photos I have are of the
finished product being presented to my DIL (first male grandchild was
born 3/21/2009). See them at:
http://web2.airmail.net/xleanone/index.html/Kathy%20Chest/
If you look closely at the upper panel in photo #3 you can see the
inlaid "extra" tenon. Maybe that'll help.
Regards.
Tom
On Mon, 18 May 2009 10:48:19 -0700, SonomaProducts.com wrote:
> You could switch to floating tennons. Just mill the current morti
> (plural of mortise) ;^) deeper, cut off the tenons and mortise the rails
> for the floating tenons.
The floating tenons were my first thought, but as I said in my post the
stub tenons almost meet in the center of the legs as is, so floating
tenons couldn't go much deeper. Oh well.
Others suggested pocket screws and that would work. I just hate to use
screws in "good" furniture. But I may.
Nobody commented on my idea of gluing in the oak panels for the first
inch against the leg, thus making that part of the panel a structural
member. I don't think cross grain gluing for an inch would present any
problems, but let me know if you think otherwise.
--
Intelligence is an experiment that failed - G. B. Shaw
"Larry Blanchard" wrote:
> It uses
> stub tenons (3/8" thick, 3/8" deep, 2.5" and 4" wide). After I got
> everything all cut it occurred to me that they were using the
> plywood
> panels as structural members. Well, I'm not using plywood so my oak
> panels are free floating.
IMHO, you have two choices:
1) Use a stronger adhesive than the plans specify, probably epoxy.
2) Time for a trip to buy some plywood.
Somehow, think you have already thought of #1<grin>
Have fun.
Lew
> It's a frame and panel with the legs serving as frame edges. It uses
> stub tenons (3/8" thick, 3/8" deep, 2.5" and 4" wide). After I got
> everything all cut it occurred to me that they were using the plywood
> panels as structural members. Well, I'm not using plywood so my oak
> panels are free floating.
IMO, that's it little weak but it will probably be OK as is if the joinery
well-fitting.
Have you considered reinforcing with pocket screws? From the bottom they
will not tbe seen and they could be out of site inder your top lip. You can
will them with the those oak filler things that they sell.
Just an option.
-Steve
It will probably be fine for 10 years but doesn't bode well for the
longevity on an heirloom with such shallow joints.
You could switch to floating tennons. Just mill the current morti
(plural of mortise) ;^) deeper, cut off the tenons and mortise the
rails for the floating tenons.
My little philosophy on floating tenons is to pin both sides to get an
equal mechanical strength as a standard M&T joint. In this case (pun)
you could pin them from the inside on one or both ends per your
preference.
On May 18, 9:17=A0am, Larry Blanchard <[email protected]> wrote:
> My wife kept reminding me that I'd promised to build her a blanket chest
> - she claims 20 years ago :-). =A0So I've started on one. =A0I didn't wan=
t to
> spend a lot of design/rejected/design time so I picked a plan out of a
> Wood magazine and she approved it.
>
> It's a frame and panel with the legs serving as frame edges. =A0It uses
> stub tenons (3/8" thick, 3/8" deep, 2.5" and 4" wide). =A0After I got
> everything all cut it occurred to me that they were using the plywood
> panels as structural members. =A0Well, I'm not using plywood so my oak
> panels are free floating.
>
> So now I'm worrying if the stub tenons are strong enough. =A0I've thought
> of a few possible fixes. =A0I could glue the edge of the panels that go
> into the legs along the edge and across the 1st inch of the top and
> bottom. =A0That would add some strength.
>
> I could add a couple of dowels to the rail/leg joints but they'd have to
> be offset because the grooves in the legs almost meet now. =A0For that
> reason there's no room for floating tenons.
>
> There's also a 2" wide ledge glued to the top edges of the rails and legs
> so that does add a little strength.
>
> Or I could admit defeat and go buy some oak plywood and save all my
> nicely resawn quartersawn 3/8" panels for some future projects.
>
> Am I being overly cautious? =A0I don't expect the chest to take a lot of
> racking or rough handling. =A0Maybe it'd be fine just the way it is.
>
> --
> Intelligence is an experiment that failed - G. B. Shaw
You could add some attractive wood or brass internal braces. Sure, they
would make the interior a little less "clean", but they could beef up
the structure while maintaining the attractive frame-and-panel construction.
I made a blanket chest many years ago with glued-up solid oak sides,
dovetailed. Well, eventually, one side warped enough to break the glue
joints in the dovetails. My current plan is to clamp the side back to
square, then install dowels through the dovetails to reinforce the glue
joints. Not as "pure" as the original design, but sometimes you have to
make modifications...
Sam Maloof uses screws in his furniture. It has got to be considered
"good" furniture by anyone's standards. He tells the purists to just
think of them as metal dowels.
BTW - Maloof says he has never had any problems with the screws in 60
years of using them.
On Mon, 18 May 2009 22:28:35 -0500, Larry Blanchard
<[email protected]> wrote:
>On Mon, 18 May 2009 10:48:19 -0700, SonomaProducts.com wrote:
>
>> You could switch to floating tennons. Just mill the current morti
>> (plural of mortise) ;^) deeper, cut off the tenons and mortise the rails
>> for the floating tenons.
>
>The floating tenons were my first thought, but as I said in my post the
>stub tenons almost meet in the center of the legs as is, so floating
>tenons couldn't go much deeper. Oh well.
>
>Others suggested pocket screws and that would work. I just hate to use
>screws in "good" furniture. But I may.
>
>Nobody commented on my idea of gluing in the oak panels for the first
>inch against the leg, thus making that part of the panel a structural
>member. I don't think cross grain gluing for an inch would present any
>problems, but let me know if you think otherwise.
StephenM wrote:
>> It's a frame and panel with the legs serving as frame edges. It uses
>> stub tenons (3/8" thick, 3/8" deep, 2.5" and 4" wide). After I got
>> everything all cut it occurred to me that they were using the plywood
>> panels as structural members. Well, I'm not using plywood so my oak
>> panels are free floating.
>
> IMO, that's it little weak but it will probably be OK as is if the joinery
> well-fitting.
>
> Have you considered reinforcing with pocket screws? From the bottom they
> will not tbe seen and they could be out of site inder your top lip. You can
> will them with the those oak filler things that they sell.
>
> Just an option.
And probably a pretty good one based on the number of frame and panel
chests/cabinets, with sides joined with pocket hole joinery, seen at ww
shows the past ten years or so.
--
www.e-woodshop.net
Last update: 10/22/08
KarlC@ (the obvious)
... then install dowels through the dovetails to reinforce the glue
> joints. Not as "pure" as the original design, but sometimes you have to
> make modifications...
Essentially what you have then is a cylindrical through, loose tennon. IMO,
not a bad option, effective and relatively simple to execute.
Yes it will show, but 98% of the population will never realize that the
purity of design has been tainted. Just the wood freaks and joinery zealots
will know. Thats pretty much just us, and you have already confessed. :-)
-steve
"Lew Hodgett" <[email protected]> wrote in message
news:[email protected]...
>
> 1) Use a stronger adhesive than the plans specify, probably epoxy.
>
Yellow glue is stronger than wood. A stronger glue wouldn't make any
difference.
"CW" wrote:
> Yellow glue is stronger than wood. A stronger glue wouldn't make any
> difference.
Absolutely true if good joinery techniques are maintained; however, if
gap filling properties come into play because of less than best joint
construction, different ball game.
All adhesives develop their strength in shear along a joint with good
fit.
As soon as the joint is less than best, the strength of yellow glue
will be degraded since it doesn't have particularly good gap filling
problems.
Epoxy OTOH, does have good gap filling properties, so it becomes a
question of how good are the joints.
If high quality joints, yellow glue is as high a quality as needed, if
not epoxy can be a CYA solution.
YMMV
Lew