Thread: The strength of Hardwood long beam with Joins?

A couple of years back i had the opportunity to go on a tour of a timber mill in Colac, one of their value added products was finger jointed radiata pine panels and posts like the one you described. Samples were regularly taken and stress tested. Pretty sure every sample i saw in their testing lab had failed in the timber and not at the glue join.

If you are loading the post vertically the stress on the joins will be compressive so i wouldn't think it would be a problem.

50 x 50 is pretty solid

is your intended use a beam (i.e. horizontal) -- or a column (i.e. vertical)?

if a column is the 40kg load axial (i.e. down the centre of the column) -- or off axis?

Originally Posted by ian

50 x 50 is pretty solid

is your intended use a beam (i.e. horizontal) -- or a column (i.e. vertical)?

if a column is the 40kg load axial (i.e. down the centre of the column) -- or off axis?

Hi, a column. The load is off axis, by about 30+cm

thanks.

I don't think there will be a problem.

However, do you have a sketch of how you intend to use the column?
What provision have you made to resist buckling over the 2m length? braces, or struts, or shelves, or ...

Originally Posted by ian

I don't think there will be a problem.

However, do you have a sketch of how you intend to use the column?
What provision have you made to resist buckling over the 2m length? braces, or struts, or shelves, or ...

Hi,

I don't think any braces or support are needed, as its holding the load for short periods (10mins) & is pretty thick. It bows a little.

cheers

Originally Posted by Tegmark

Hi,

I don't think any braces or support are needed, as its holding the load for short periods (10mins) & is pretty thick. It bows a little.

that's what would worry me.

The duration of the load is not really relevant.
However, the strength of any post (or column) declines rapidly as the post bends and even a little nudge to the bow can induce catastrophic failure

see attached diagram
50 x 50 Column.jpg

Originally Posted by ian

that's what would worry me.

The duration of the load is not really relevant.
However, the strength of any post (or column) declines rapidly as the post bends and even a little nudge to the bow can induce catastrophic failure

see attached diagram
50 x 50 Column.jpg

Hi, nice diagram.



I decided to back the weight off a bit to 33kg, here is a diagram of top section, I just had a question about the support.



The blue support will be bolted into the wood where indicated at red line, I'm wondering what is the minimum thickness bolt needed for strength? I would like to go 6mm as any wider & the width of the wood suffers. What about two 6mm bolts one on top of the other? would the load spread on both bolts evenly?

thanks