.75 MDF, what size/type of screws to use?

[PV Audio 5,000+ posts]

The same size as well? If so, you still shouldn't even bother with 3 and just get 2.

 

[o6blink 10+ year member]

Yeah, they were all the same size. I'm just saying though.. I got the II. Took me about a half hour to find the wood glue, their stupid employees couldn't even find it.

 

[helotaxi 5,000+ posts]

From what I've been told, wood glue emulsifies the woodfibers at said joint and bonds the pieces together. This is why it's nearly impossible to directly shear a wood glue joint apart when it's fully set. It holds true for other glues, but you'll just keep tearing the wood shorter and shorter and the glue won't actually separate. I'm sorry as well though, because I'm very ignorant when it comes to things I've been told, so if you are in fact right, then I learned something new today. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Like I said, the glue integrates itself with the wood and forms a composite material at the joint. The composite is stronger than either of the parts. Think fiberglass.

And the "soaking in" reasoning doesn't really work very well because cyanoacrylate glues do the exact same thing, but they aren't designed for porous materials...

Exactly, most CA glues aren't designed for porous materials. The bond is formed through surface adhesion alone just like epoxy. CA forms a film on the surfaces to be joined and the thinner the film, the stronger the joint. Any imperfection in the surfaces will weaken the joint. If the CA soaks into the material, it can't fomr a bonding film and the surface isn't flat either.
Wood glue fills the pores in the material and cures as one piece with the wood integrated into the solid.

 

[PV Audio 5,000+ posts]

Gotcha. //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif