Thanks for posting that Ralph.? You can always learn from people like him.
Tensioning
I went down to the workshop after seeing it, and set up a 10-14 bimetal blade with the load cell spliced into it and tensioned the blade to the midpoint of the manfr stated range for bimetal blades?(25-30,000psi stress).? Then put a small piece of round steel that was a nice sliding fit in the blade guard fixing hole and found the distance at which it first touches, when tapped like he did.
Maximum distance between steel piece and blade at 1st hitting was 2mm (5/64").??
Just open the guard and slide the piece of steel up to a feeler gauge set or a bit from any 2mm sheet stock, lock the steel piece with your fingers while sliding the the feeler gauge out, then tap away a few times at each tension setting.? When you hit the steel piece, you'll see it jump away.? It's easier to over-tension and reduce the tension until the tapping hits it.? ?
There's reasons it would be different from his recommendation.? The span between the wheels is smaller on a 4x6 and he said "...no more than 1/8" and I presume that includes different blade widths and thicknesses. For a normal 14" wood band saw that's probably significantly tighter than most people would tension their blades.
This is better than ANY of the 4x6 saw manufacturer's methods.? Bear in mind that 2mm is the midpoint of the acceptable tension range, so you're pretty safe with over- and under- 'tapping' it. Good for a 4x6 but I'm not sure that it helps you with your Bainbridge 712 Darren.?
Tracking
His recommendations for crowned wheels like Darren's makes sense, though the reliance on the manufacturers setting for the bottom wheel is no help to Darren who suspects its all been changed.? Then co-planar is a good start point I think, as much as he rubbishes it.
His recommendations for side roller setting don't specifically apply to a 4x6 since our guides twist the blade.
I've not found the rear support roller setting to be critical like he does.? I run mine just clear for most of the rotation of the blade, but the welds vary so much the back of the blade moves around quite a lot.? You just don't want the back support rollers set too far forward.?I once found, when mine were set ~1/4" too far forward by mistake, the weight of the sawframe used the back support roller (esp the lower one) as a pivot to de-rail the blade.? If the blade is close to the rim on the bandwheels and the back support rollers are 0~1/32" (0~1mm) clear, then the sawframe weight will push the blade back against the rollers without deflecting the teeth sideways at all - jv
