Screw length for thicker wood

[James Wood]

Hi,

 

I need some advice on joining larger thicknesses of wood using the kreg jig.  I don't see a recommended screw length for say joining 4 inch lumber.

 

Thanks

[James Wood]

Yes, some advice would be good.

 

Looking at the attached file, what would be the best way to join the piece shaded red and the piece shaded blue to the vertical shaded orange.  They will be attached on opposite sides.  Normally I would go for a pocket hole using the kreg.

 

[John Schaben]

those members are both structural and load bearing. lag screws/through bolts or you can get someone hurt.

[James Wood]

Thanks for the great advice. 

 

Yes, it's a childrens' play area for my kids.

 

Sure there are kits available but there's no satisfaction in putting together something manufactured. 

 

Not sure if joist hangers are available here in Italy but I am sure there is something similar to be had.

 

Thanks again for the help.

 

 

[Jack Dillard]

Any advice on joining full 2x6 cedar boards

 

[Ken Darga]

James, 

Check with your local community/village code dept---

some communities require the structure be to code.

You are liable for any personal injuries to persons, that may result from structure failure.

  Use 5/16" min dia bolts for 2x4 ---

3/8'' bolts for 4x4 ---

1/2'' bolts for 6x6 members---

plus washers- (1 under the hex head of a bolt head and 1 under the nut with a lockwasher---

hex-nut fasteners---

galvanized finish. 

If using hex head bolts, recess the bolt heads, so they are flush with the surface---

locate the nuts on the inside/underside of the structure members, 

so as to reduce the likely hood of anyone getting snagged on a bolt head or screw tips.

  I'd prefer to use carriage bolts--- they have a rounded head style, akin to a truss head, then you won't need a washer under the head.  The square feature under the head will grip into the wood, so the bolt won't rotate when tightening the nuts.

  Avoid lag screws/bolts---they loosen over time, resulting in loose joints.

  Lag bolts are acceptable, but for some limited applications---

such as, when you cannot access the back side and use a nut.

The thread engagement of a lag bolt should be 2-1/2 times the thickness of the member you are fastening---

also there are minimum spacing for lag bolts. Check with applicable local construction codes.

[Ken Darga]

What's your intended design and application?

Jack Dillard said:

Any advice on joining full 2x6 cedar boards