Thread: Rounding a new bandsaw blade

I just use an old oil stone.

What he said,

Thanks Sir S and vk4. Do you oil the stone first? Does it generate sparks?

No I do not oil the stone first. It is an old one that isn't really used for anything and seems to have a small degree of oil in it. As for the sparks, whilst it could be a concern I haven't had any issues. I find that it is just a quick light touch that is required to round the back off the blade and I would generally just place the stone flat on the table and swing it in a arc across the back of the blade. To reduce the spark issue it would be best to clear any saw dust. It may also be worth cutting into some mdf to create a zero clearance table around the blade (for want of a better description) to close up the insert that is typically around the blade to assist with dust extraction. This would help reduce the possibility of sparks entering the body of the bandsaw.

What’s the use of rounding the rear edges of a new band saw blade? All I knew is to have proper break-in procedure to a new band saw blade before cutting.

Originally Posted by bosox

What’s the use of rounding the rear edges of a new band saw blade?

When cutting tight corners, a corner on the back of the blade will catch on the timber as the timber turns and the cut touches the rear corner. If the rear corners of the blade are rounded over, this is much less likely to happen

As Dengy has stated it does help when cutting tight curves at the limits of the blade. Whilst not really necessary for re-sawing applications I do find it makes a small difference when working on the tight curves of bandsaw boxes, and also when backing out of cuts, which is sometimes unavoidable. The difference may be so small that it isn't worth it, but given it takes all of two seconds I still do it as a standard practice for new blades.

It also helps to remove the sharp edge at the back of the blade which helps protect your fingers when supporting the timber behind the blade teeth (again mostly bandsaw boxes).

The other good thing is to ensure that the weld is smooth on both the sides and the rear.

Cheers

Stinky.

Originally Posted by bosox

What’s the use of rounding the rear edges of a new band saw blade? All I knew is to have proper break-in procedure to a new band saw blade before cutting.

What is the correct run in procedure. Sorry for hijacking your thread Dengue

Originally Posted by Dengue

When cutting tight corners, a corner on the back of the blade will catch on the timber as the timber turns and the cut touches the rear corner. If the rear corners of the blade are rounded over, this is much less likely to happen

Is this method the same as what we call as blade break-in procedure?

When I round off the rear edges I use a DMT diamond whet stone and have had no problems. As has been said it stops the rear cutting on tight curves, but it also allows you to tighten those curves even further.

I always use a 1/4" 6 skip for almost everything. I don't do any BIG cutting and over the past 15 years or so it's been fine, but when I'm doing small bandsaw boxes it means I can cut tighter curves than the quoted 3/4" rad.

Originally Posted by ozhunter

What is the correct run in procedure. Sorry for hijacking your thread Dengue

Sorry for quite a late reply. Didn’t notice this post until now.
The proper break-in procedure should be observed in every new band saw blade.
New, sharp teeth are more fragile than lightly honed teeth. Break-in hones the teeth and helps make all the same height. Proper break-in results in less blade strippage and longer blade life.
The break-in procedure: think of the teeth like a freshly-sharpened pencil..(this is mostly applicable to metal cutting)
1. Set proper blade speed for the machinability and size of material to be cut.
2. Reduce the normal feed rate by approximately 50% of the regular rate for the first few square inches
3. Watch the chips
Small flakes ---- insufficient feed
Heavy blue chips---Excessive feed
Spring curled no color---proper feed rate