ian maybury
03-29-2015, 8:55 PM
Just looking for some confirmation. I've been building a tool cabinet from what has despite promises turned out to be low quality Eastern sourced 18mm WBP ply which has defects like overlaps in the internal veneer layers, and has layers of a relatively soft pulp wood used for two three of the laminations. The classic reddish brown stuff - that actually was pretty decent until recently. Some pieces warp quite badly (usually around internal defects) when cut free from the main panel and go in the bin, but in the plane of the panel - no sign of cuts closing or anything.
I'm getting isolated lightly scorched/browned patches, maybe 1 1/2 in long in random locations along cuts off the fence. None in some cuts, maybe one or two in another cut of 12 - 18in long. The saw is a Hammer K3 slider, and is accurately set up with maybe 0.001 in toe out. (checked several times - my first thought was that maybe something had moved) The blade is a Felder Universal sharpened very well by Leitz, and proven in cuts in other materials to be a really clean cutting - pretty much splinter free on even cheap ply cross cuts if set low.
My best guess is that what's going on is that there are patches of either resious wood, or maybe small patches where the (improperly heat cured - does that happen?) adhesive isn't clean cutting. I've cleaned the blade a couple of times (only moderate amounts of a softish yellow/brown build up on mostly the sides of the teeth - very easily removed with degreaser and a light brushing), which more or less resolved the issue - but it's coming back after only maybe a few feet of cutting if that.
Does anybody recognise this pattern of behaviour, or know what the cause is? Does e.g. waxing/or PTFE coating help to slow this sort of build up? Guess i'm wondering too if it's likely to be a feature of cheap Eastern ply going forward because it's a right PIA...
I'm getting isolated lightly scorched/browned patches, maybe 1 1/2 in long in random locations along cuts off the fence. None in some cuts, maybe one or two in another cut of 12 - 18in long. The saw is a Hammer K3 slider, and is accurately set up with maybe 0.001 in toe out. (checked several times - my first thought was that maybe something had moved) The blade is a Felder Universal sharpened very well by Leitz, and proven in cuts in other materials to be a really clean cutting - pretty much splinter free on even cheap ply cross cuts if set low.
My best guess is that what's going on is that there are patches of either resious wood, or maybe small patches where the (improperly heat cured - does that happen?) adhesive isn't clean cutting. I've cleaned the blade a couple of times (only moderate amounts of a softish yellow/brown build up on mostly the sides of the teeth - very easily removed with degreaser and a light brushing), which more or less resolved the issue - but it's coming back after only maybe a few feet of cutting if that.
Does anybody recognise this pattern of behaviour, or know what the cause is? Does e.g. waxing/or PTFE coating help to slow this sort of build up? Guess i'm wondering too if it's likely to be a feature of cheap Eastern ply going forward because it's a right PIA...