Thicknesser Chipout

[Simon_B]

Hi all

I bought a second hand Ryobi thicknesser a while back. Yes I know it's cheap and cheerful, but my budget for power tools is somewhat limited.

I have cleaned up some old decking boards with it with a view to making a new computer desk. The finish looked fairly decent, and I was happy with the outcome.

However I have a whole load of reclaimed pine boards that I also want to clean up for other projects. However I'm getting some pretty severe chip out, or more like it's lifting and folding the fibres, rather than cutting them.

I have tried feeding the other direction and get pretty much the same result.

Why would this happen?

Blunt blades? But it seems ok with harder wood.
Crap wood? It is exceptionally dry
I'm just rubbish? Be kind, I'm a newby to thicknessers.

 

[eribaMotters]

Your blades may be a bit blunt and likely to tear the timber. which I would assume is quick grown and not very dense. Also it looks like a change in grain direction around the knot is adding to your problem.

Colin

 

[rogxwhit]

Your worst tearout will likely be on one side of that knot from feeding in one direction, and on the other side of the knot from feeding in the opposite direction.

Reclaimed wood will likely have embedded grit that'll chip / dull your knives. It might help to go over all surfaces with a wire brush before planing.

Fresh knives (you may gauge the sharpness by the sound when planing) - a light cut - and a slow feed if there's a choice.

But it's not the best material, and quite coarse-grained.

 

[Ollie78]

That's just a horrible bit of wood. Not much you can do.
I would belt sand it instead.

Ollie

 

[MARK.B.]

All of the above +1

 

[D_W]

imagine how the knives will enter the wood, rotating, and get an idea for the arrangement of the straws in the wood. if the cutterhead can't scoop in and sever across the straws, but rather ends up entering the wood cutting straight down between them and prying them apart, breaking them off where they decide to break further down, you'll have problems.

There's a bag of tricks for this, but probably the best with a simple thicknesser is just to do a few passes with far lower thickness once you're close. That limits the thickness of the chip the knife is prying (instead of cutting) due to grain direction.

 

[Fitzroy]

As per above, but I have found I can minimise it with sharp knives and fine cuts. But normally I just accept it coming off the thicknesser and then hand plane the surface afterwards to finished size to remove the tear-out.

 

[Jacob]

Might be better if you do a first pass with a light cut to just flatten it a bit, then turn it over and do other side the same, and again as necessary - keep turning with a light cut each time.
And have the blades sharpened!