Planer set up

[ajbell]

Thanks - I am learning so much!

I bought a book on the planner / thicknesser but think I have
learnt more from this forum in the past dozen or so posts!

I will recheck with the straight edge know I know what to look for!

Andy

 

[Digit]

Actually a slight concavity does matter aj, especially if it's a long piece 'cos then a smoothing plane might well remove the marks but it still leave the wood concave.

Roy.

 

[OPJ]

My tutor was telling us this week that when edge-jointing boards, we're advise to add a slight hollow (concave) to the edges which apparently allows the boards to move without splitting the tops...?

I have heard of this before, even from people on this site. It's interesting but, I've never had a problem gluing up straight edges.

 

[TrimTheKing]

My tutor was telling us this week that when edge-jointing boards, we're advise to add a slight hollow (concave) to the edges which apparently allows the boards to move without splitting the tops...?

I have heard of this before, even from people on this site. It's interesting but, I've never had a problem gluing up straight edges.

I would guess that on properly prepared and seasoned wood then the problem isn't so apparent. If you haven't seasoned the wood well and it loses more moisture, this will go from the ends first thus potentially opening up the joints.

But as you say Olly,on the few things I have made I haven't yet had a problem with straight edges, but I do now do all panel glue ups with slightly sprung joints just to be on the safe side :wink:

Cheers

Mark

 

[Digit]

I was taught the same, but I have never heard of any definitive test to support it. The idea dates, as far as I am able to ascertain, to the days before modern glues, though whether there is any relevance in that I'm not sure.
What does seem odd to me is the suggestion that we should assemble our boards under some form of built in tension.
Based on personal experience I have to say that it doesn't seem to prevent table tops of yesteryear opening from the ends first.

Roy.