Woodworking is not immune to myths and misinformation and some of it is shared unknowingly among the enthusiastic newbies to woodworking. What amazes me is some of this stuff has been around for years and years it keeps showing up in books and magazines.
Watch it on Youtube: https://youtu.be/W4FaoSJD6Mg
At first blush, some of these things appear like they are good ideas, and some people who try them will often tell others how well some little tip worked, not even knowing what it compared to ...
And one of my favorites is using masking tape to make cleaner cuts. And we have all seen these on the Internet, in books and magazines. I always questioned how something like masking tape, that a child can rip in half ... could actually make any difference between a carbide-tipped blade and any wood, which is many times stronger.
In the picture below, these are 2 results from 2 test I made using Red Alder, and the same board. The piece of wood to the left shows the results of cutting through the wood, on a table saw, the Zero cut is with just a plain cut through the wood using a Freud 80 tooth blade, the other cut on that same wood is using masking tape to make the exact same cut.
Below, is a picture of what that test cut looked like. The best cut of any blade on a table saw is where the blade enters the wood first, and in this case, the blade enters the TOP of the wood first, so no matter what, it will always be the best cut of what a blade can do. Adding masking tape to what is already the best cut is a complete waste of time.
Referring back to that first photo of the 2 cuts of wood, the right side of that picture shows the UNDERSIDE of 2 cuts on the miter saw. The right cut on that wood is without ANY kind of blade support, there is NO insert and the evidence is a nice perfect, clean cut again with the same 80 tooth Freud blade. The second cut on that same block of wood is with using a thin piece of plywood as "the perfect" zero clearance insert, and again you can see the cut is near perfect.
Anyone who has installed a hardwood floor will know that on a chop saw or miter saw, (and even with a circular saw) the best cut is made by placing your wood Face Down. The reason for this is that on these saws the blade enters the wood FIRST from underneath, so the very best cut is underneath the wood. If there is any tear-out, it will be on TOP of the wood being cut. Therefore the only real value of a zero-clearance inserts on a miter saw is to stop bits of wood from falling into that trough under the insert.
The picture below is of a miter saw with a very normal distance between the blade and the inserts
The picture below is what a "perfect" zero clearance insert would look like on a miter saw by using some thin plywood.
Bandsaw Blade Myth
This myth has been around for 3 decades that I can remember, and that is ... "If you round off the back of your bandsaw blade, your blade will be able to make tighter circles or arcs". First of all, I have never been able to establish any scientific evidence that this works, so anyone who can do this for us, and provide some proof, we would all be grateful. In the meantime, the best way to treat your bandsaw blades is NOT to force them to do something they are not designed to do.
When you force wider blades (designed for ripping and resawing) to cut circles, and you force the blade, in many instances you are forcing teeth on one side of the blade into the wood, creating more friction ... and heat, and in some cases hot enough to begin to melt the steel to the point the teeth become slightly dull. As I have said in other articles in the past when teeth on one side of the blade get slightly dull, the blade will not cut true and this creates what we commonly call "blade drift". The blade will still cut, but not straight, so you have to push the wood through at an angle.
Do yourself a favor, save money and time and get at least 2 bandsaw blades, one wider blade for resawing and one narrow blade for cutting circles and arcs and your blades will stay sharper longer bu this means you may need to take a moment to change blades, your blades will thank you and so will your bandsaw, and you will never have to worry about rounding over the backs of your blades.
I had forgotten about this myth until someone asked me not long ago if they should be draining their batteries in the drill. Quick answer - NO.
The first generation of rechargeable batteries was called Nickle-Cadmium or NiCad. These batteries, in the course of 18 months of infrequent use, would develop a "memory" which meant that a battery that still had half a charge in it, was recharged to top it up, after several months it would only retain that charge up the amount so you would not get full use of the battery. To rejuvenate these batteries you could discharge and recharge them a few times and once in a while, they would again start taking and using a full battery charge.
With the new Lithium batteries that have been around for at least 10 years now, they do not require any rejuvenation ... just charge them and use them as they were designed.
What I like about myths similar to these, is that it makes us think about what we are doing and ask questions like ...
"Does this sound reasonable?" and
"what problem is this solving?"
"Is this a safe solution?"
All the questions that help make us better woodworkers and think more about the craft and how we approach it ...
Copyright Colin Knecht