Friday, November 18, 2011

V2.31 - What a ‘shocking’ development

With winter coming on, and it being the time of the year with very low humidity, I’m thinking it’s time to talk about the stuff that makes us jump out of our skin. Static electricity in your woodshop. I’m sure we’ve all experienced it when using our belt sanders. You’re just sanding along, minding your own business, and then your finger gets too close to the table and POW, all of a sudden you think your wife snuck into the shop and zapped you with her Taser. But no, it was just your ‘friend’ Static Electricity. It can show up on all rotating equipment and especially in your dust collector ducts.

Static electricity in a wood shop is mainly caused by two things. First is low humidity in the air. Static is especially troublesome in winter when the outside temperatures are low. A rule of thumb is the colder it is outside, the lower the humidity is inside a heated shop. As a result, static charge builds up easily and causes shocks when the electricity discharges through contact. The problem is even worse if a shop’s dust collection system exhausts its air outside the building. This builds an additional requirement for fresh air coming in and the fresh, cold air will have low humidity once it has been heated indoors.

The second thing that causes the static electricity problem is motion between two things. In the case of a belt sander, it is the motion between the belt, platen and pulleys that causes the build-up of electricity. In the case of the dust collector or Shop-Vac, it is the motion of the particles through the hose. There are two places where the charge can build up. One is in the machine the dust collector is attached to and the other is on the person who is operating it. Fortunately, grounding the frame of the machine will eliminate the buildup of the static charge. All fixed machinery, such as a table saw, jointer, planer etc., should have its frame grounded to a water pipe or at the very least, to the ground conductor or conduit sheath of the machine’s electrical wiring. Sometimes this is not possible, especially if the machine is electrically double insulated, as is the Shop-Vac.

Beyond grounding the machine, the best cure for static problems is to try to keep the humidity in the shop from getting too low. This can be done by using bag-type dust collectors that re-circulate the same air within the shop after the dust has been removed. These collectors will also reduce your heating bill. Other ways of adding moisture to the air, such as using humidifiers, are worth considering. Another thing you can do is wear shoes that bleed off the static charge rather than allowing it to build up.

Send your questions or comments to:
Toolsmartz@bellsouth.net and we’ll see what we can do to help you.

Wednesday, November 9, 2011

V2.30 - Bench Grinder: Tips & Techniques

Ok, back to farm…We’ll finish up our look at Bench Grinders with a few Tips & Techniques. Every once in a while, we run across something new about Bench Grinders, but most of our knowledge is tried & true, and time-tested.

First off, every ‘store-bought’ grinding wheel that I know of has blotters on its sides. ‘Blotters’ are those pieces of paper, or cardboard, on each side of the wheel. While they might look like just a convenient place for the manufacturer to put warnings and such, they actually do serve a very critical purpose. When a wheel is put on a grinder, there are metal flanges that squeeze against the sides of the wheel. If the wheel had no blotters, those flanges would be tightening up against the actual rock of the wheel and you would stand a very good chance of cracking the wheel. Blotters provide a ‘buffer zone’ between the flanges and the wheel rock and thereby cushion and distribute the tightening force. Bottom line: Don’t buy a wheel that has no blotters or, if you do, don’t put it on your grinder without making some blotters and using them.

While we’re talking about blotters, they have another use. Most manufacturers put their product warnings on them and one of the major warnings is “Do not grind on side of wheel”. Now, do most of us follow this warning? Probably not, but I am here to tell you that if enough sideways force is applied to as grinding wheel, a wheel explosion is a very real possibility. Years ago, I saw a training film (yes, “film”- not tape or DVD- I’m dating myself) wherein a grinding wheel explosion was created and it is not a pretty sight. Even though I might use the side of the wheel to do some very light & delicate, precise grinding, I’m only able to do so because of my many years of experience with this and I know that I am not applying any sideways force at all. My general advice to everyone is: Don’t grind on the side of the wheel.

Lastly, always keep the tool rest adjusted as close to the wheel as possible, in order to provide the most support for what you are grinding on. Use your safety glasses. Keep the grinder’s eyeshield in place to provide added protection. Make sure the spark arrester is in place and adjusted to within 1/8” of the wheel and always keep an open container of water handy for cooling off your material. If your grinder has a factory water pot, that’s even better. Keep it full.

These hints, and our previous bench grinder columns, should help you get the most out of your Bench Grinder. Happy Grinding!

Send your questions or comments to:
Toolsmartz@bellsouth.net and we’ll see what we can do to help you.

Sunday, November 6, 2011

V2.29 - Seat Belts – buckle up, please

If you’ve spent any of your precious time reading these little articles of mine, then you’re probably aware that I’m known to go off on a tangent at times. Welcome to the latest one.
We recently had another youngster die because she was not wearing her seatbelt and got ejected from her car in a vehicle accident. I’ve seen reports that ‘she was doing everything correct- not speeding, not drinking, etc’, but when she chose to drive without her seat belt buckled, she was putting her life at risk when this just did not have to be. Please understand, I am not ‘piling on’ and saying she caused her death. I have nothing but compassion for her friend and relatives. I am so sorry that they have to go thru this, but people, if you don’t want your folks to possibly go thru this - buckle your dad-burn seat belt.
How anyone can drive a car without fastening their seat belt is beyond my understanding…but it was not always this way. I used to drive cars that did not even HAVE seatbelts. (Please note that I have installed seat belts on all 3 of my antique cars. I will not drive without them) I can remember driving my 1950 Ford all over the country without it even having a seatbelt. It does now.
My ‘moment of realization’ came in 1990. I had been driving my dirt stock car for 3 seasons by then and wouldn’t even THINK of racing without wearing my 5-point harness. (On the side note, I wonder why all racecars have shoulder harnesses and lap belts? Perhaps because it can save the life of the driver in an accident?... well DUH) So, here I was driving down the interstate in Memphis, TN on my way to work in my 1982 Chevette (yes, I had one - don’t laugh) no seatbelt on and it was raining cats & dogs. Well, all of a sudden, I started hydroplaning and the car began to slide sideways on the road. Fortunately, there were no other cars close to me and I just let off the gas pedal and when the car slowed down enough, I got traction back. Well, I got to thinking, ‘what if I had slid far enough to slam into the guard rail? Most likely, I would have been thrown across the car and would not have even been behind the wheel any longer. You can’t drive if you are not behind the steering wheel.’ Those were my thoughts…and I immediately buckled my seat belt and have not driven a car without doing so since.
My point is, why risk your life if you don’t have to? EVERY time you get out on the public road, something my happen to you. They are called ‘accidents’ for a reason – no one plans them. PLEASE buckle your seat belts and live to tell about it.

Send your questions or comments to:
Toolsmartz@bellsouth.net and we’ll see what we can do to help you. _______________________________________________________________