LumberJocks

Low angle miter with spline, strong enough?

  • Advertise with us

« back to Joinery forum

Forum topic by kaloosick posted 05-24-2013 09:39 AM 907 views 0 times favorited 14 replies Add to Favorites Watch
View kaloosick's profile

kaloosick

6 posts in 515 days


05-24-2013 09:39 AM

Hi all, I am working on a dresser of sorts. My wood is a 4’x4’ sheet of walnut plywood 3/4” thick. My plans call for a low angle joint (5 degrees) to join a 2 foot section with a 4 foot section along the end grain. My plan of action is to miter the end of the lower piece only (the 2 footer) to 5 degrees and then place a piece of 1/8” thick aluminum at 3/4” depth as a spline inside the end grains of each side. I am essentially trying to join end grain to end grain, ambitious as it may be, cleanly and without evident joinery. I would opt for a lap joint instead but the overlapping sections would end up being too short given the 5 degree angle change between the pieces.

Any thoughts on the strength of such a joint? The two pieces compose the side panels, and I am considering a gusset on the inside if not also the outside of the joint if opinion here is that I am being too optimistic about the strength.


14 replies so far

View ChrisK's profile

ChrisK

1193 posts in 1767 days


#1 posted 05-24-2013 12:09 PM

I draw a sketch of what you described and I think the joint will hold, however I would not try and cantilever the 4 foot long piece. Use a good epoxy to hold the aluminum in. You will need to be creative in clamping the joint while the epoxy cures. A longer set time epoxy will probably be a must. It would be a real challenge to get the pieces lined up and held with 5 minute stuff.

-- Chris K

View kaloosick's profile

kaloosick

6 posts in 515 days


#2 posted 05-24-2013 04:56 PM

tried to give a better idea of whats going on.

the epoxy is definitely necessary, I am also concerned about cutting slots for the spline into the plywood given how soft the interior plys are. Anyone have good/bad experience doing something like this?

View 404 - Not Found's profile

404 - Not Found

2544 posts in 1655 days


#3 posted 05-24-2013 09:03 PM

You’ve obviously given this a lot of thought. The best thing you could do is is try it with a bit of scrap and see how strong it turns out.
I’m curious why you don’t want to do a true mitre i.e 2.5° on each piece. It would probably make it easier to align the spline. An alternative way of doing this would be like this, in conjunction with biscuits.

View Loren's profile

Loren

7723 posts in 2334 days


#4 posted 05-24-2013 09:28 PM

Have you considered folding the joint?

Keep in mind those veneers on commercial ply
are very thin and even a little sanding of the miter
can mess up the way the veneer takes a stain
or finish. There’s a layer of glue underneath and
when you sand too much the glue starts to
block finish absorbancy.

I’d consider making a fine dado cut with a narrow circular
saw blade and folding the miter – kerf bending with
one kerf basically. For that matter, I don’t know
what width the kerf has to be to bend a piece to
5 degrees, so more than one kerf might look
better.

-- http://lawoodworking.com

View jumbojack's profile

jumbojack

1198 posts in 1310 days


#5 posted 05-24-2013 10:24 PM

i have done this many times with solid wood. We build ukuleles and the head and neck are at 5 to 7 degrees. We use dowels and a horizontal boring machine to bore the dowel holes. oh and we divide the angle and cut both sides of the joint.

-- Made in America, with American made tools....Shopsmith

View kaloosick's profile

kaloosick

6 posts in 515 days


#6 posted 05-25-2013 12:33 AM

as for the kerf bending idea, I would like to do this, only the constraints of the project are that I use a 4×4 piece of wood and my plan calls for a dresser longer than 4 ft. why not just get longer plywood? Its a design competition where the 4×4 plywood is the only wood allowed. the entire reason for such an insignificant bend is to give the break in wood grain occuring at the end of the 4 feet of board on the side panel a reason to be occuring rather than just have two conjoined ppieces of ply running parallel with no explanation for the break other then “I only had a 4×4 board”

View Loren's profile

Loren

7723 posts in 2334 days


#7 posted 05-25-2013 12:43 AM

Like I said though, lining up those thin veneers may
spoil the project if you mess it up.

Test your theory first on ply with the same
veneer thickness. Doing your own veneering
is prohibited too I imagine.

-- http://lawoodworking.com

View scott ernst's profile

scott ernst

31 posts in 514 days


#8 posted 05-25-2013 01:02 AM

I think Renners’ suggestion is a good one. I’m pretty sure that your aluminum spline is strong enough, but the plywood is likely to split lengthwise at the spline when it’s stressed. If you had one a Domino machine would be pretty strong and it would line up your veneers perfectly. Epoxy is a must either way. Good luck.

-- Scott, NM www.CustomFurniture.us

View kaloosick's profile

kaloosick

6 posts in 515 days


#9 posted 05-25-2013 07:27 AM

going to do some tests tomorrow, one with a bent metal spline and one with drilled dowels.

View jumbojack's profile

jumbojack

1198 posts in 1310 days


#10 posted 05-26-2013 02:16 AM

if you can find a horizontal boring machine (Shopsmith) it is a no brainer. Cut your angle and set up the boring machine. It is very easy to do…..I did it, it must be simple.

-- Made in America, with American made tools....Shopsmith

View Moron's profile

Moron

4666 posts in 2579 days


#11 posted 05-26-2013 04:40 AM

domino with extreme confidence

a no brainer

-- "Good artists borrow, great artists steal”…..Picasso

View jumbojack's profile

jumbojack

1198 posts in 1310 days


#12 posted 05-26-2013 02:34 PM

Moron, cute kid and happy ladies.

-- Made in America, with American made tools....Shopsmith

View kaloosick's profile

kaloosick

6 posts in 515 days


#13 posted 05-30-2013 04:39 AM

metal spline worked well enough, on to the rest of the project. Thanks for the input!

View Moron's profile

Moron

4666 posts in 2579 days


#14 posted 05-30-2013 06:17 AM

no worries

-- "Good artists borrow, great artists steal”…..Picasso

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com

Latest Projects | Latest Blog Entries | Latest Forum Topics

GardenTenders.com :: gardening showcase