Today, I put on a Irwin bimetal blade. Well I did after I filed out the casting slot that the upper band wheel tensioning system uses. Prior to that, I couldn't get center to center of the band wheels close enough to put the blade on. Btw, that Irwin blade is wickedly sharp.
Wes
Praise be! I thought I was an idiot. Don't answer that...
Heck, I thought tightening until it walked and backing off a bit was the tension indicating system. Seems to work for me so far ;)
Wes
Hence my characterization of it as a superstition.
I use a Starrett 6 tpi blade for solid aluminum stock, Enco item 990-0248. Fewer teeth means higher pressure per tooth, which helps on this small size saw.
casting slot that
Make sure you season the new blade by cutting something soft like aluminum or even 1018 steel at a slow feed rate. The mfgrs. of the blades recommend running at lest 75 feet of blade slowly through a soft material to take the excess sharpness off the blade. This will help make the blade last longer.
John
casting slot that
It seemed to want to overfeed based on the spring tension I had set. I did the old hold the saw head by hand to slowly go though the first piece of stock I cut. I'll keep you advice in mind on the first few cuts.
Wes
It's highly unlikely that keeping the tension on the blade will deform the saw frame enough to matter in our lifetimes. All the references I could find for the creep rate of gray cast iron did not bother listing data for temps below about 700F.
Overtightening is a much more likely cuplrit than leaving the blade tightened between uses.
I've got to assume this is an old wives tale. Consider what would happen to bolted connections if steel stressed to a significant fraction of its yield strength at normal temperatures relaxed over time.
In article , wrote: : : I am slightly puzzled by the oft repeated recommendation to :release blade tension between work sessions. : : I cannot see the harm in keeping a strip of steel :permanently tensioned to within a large fraction of its elastic :limit - after all this is exactly what they do when they tension :the steel wires in reinforced concrete girders. : : Looking at it another way - repeatedly taking steel strip :between low stress and high stress is a fine way to induce :fatigue cracks. : : With this in mind I keep my 4x6 blade permanently tensioned.
There's one potential "Gotcha!" with that. The blade heats up during use. The frame, not so much. If you tighten a blade that's been working hard, it's going to be overtensioned when it cools unless you relax the tension first.
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