Repair/mechanic tricks and or tips?

[patrick_g]

Pat, I bow to your greater knowledge. On a business trip, the projector would not start up. It was plugged into an extension cord on a reel. I had them unroll the reel and it started fine. I blamed it on induction as the resistance was the same rolled and unrolled. Was I wrong?

Don't bow too low as SPYDERLK got it closer than I (was I asleep???) regarding the inductance. Most extension cords aren't "twisted pair" but between the counter currents in the two conductors and the randomization effect of the "jumble" of wire the inductance at 60Hz is negligible.

Regarding your projector mystery: Not being there I don't know if there was an intermittent in the extension cord or what but it wasn't inductance preventing the projector from firing up. If there weren't any technically savvy observers then you looked like a genius to the mob.

Any sufficiently advanced technology is indistinguishable from magic. Different audiences require different levels of technology before they claim MAGIC.

To get significant inductance the extension cord would have to be separate conductors inconveniently wound in series.

I have various reels for storing cords but none will hold over 100 ft and none have multiple cords on them. I tend to unroll more than I need to reduce heating if using a heavy draw on the cord.

I don't recall which magazine it was (I read several that have "clever hints" in them with suggesters winning prizes) and one of them was the bucket cord storage idea.

SPYDERLK and I agree, it seems, that heating is the hazard, not inductance.

HF and probably Cumins Tools, Northern, etc have open wire cages with a crank handle for storing an extension cord in a random jumble. The wire cage will not hold the heat as much as a bucket and the relatively open jumble won't hold the heat too badly. They are handy because you can crank a handle to quickly store the wire and just pull to get it out. (They don't get fouled often.)

Bird, Not putting your boy down, in general I see many PROFESSIONAL contractors doing lots of unsound practices, some out of ignorance and others knowingly because they accept the tradeoffs.

I admire the contractors who use a simple crochet chain stitch to neaten up their cords often repeating the process to really make compact storage. The wire always feeds back out neatly and the bundled wire is not too prone to overheating if used while partly compacted. I use this sometimes but more often coil the cord as a sailor coiling a line to be hung up (not nearly so handy as the crochet stitch but a habit from years of sailing and line handling and the finished product hangs up more neatly.)

SPYDERLK. thanks for the reminder... well du-uh... I guess I know at what age senility begins...

Pat

 

[BobRip]

Regarding your projector mystery: Not being there I don't know if there was an intermittent in the extension cord or what but it wasn't inductance preventing the projector from firing up. If there weren't any technically savvy observers then you looked like a genius to the mob.

Pat

Actually, everbody at the meeting (including me) was an electrical engineer.

 

[SPYDERLK]

Pat, I bow to your greater knowledge. On a business trip, the projector would not start up. It was plugged into an extension cord on a reel. I had them unroll the reel and it started fine. I blamed it on induction as the resistance was the same rolled and unrolled. Was I wrong?

Was it one of those spring wind reels? They have brushes that may have just needed a jiggle to make better contact. It would be interesting to repeat the experiment. If it would repeat we could learn something. Sometimes they wont repeat tho because some unobvious internal thing changes, like switch contacts being exercised, or a motor being jogged out of a "dead" position, or the incidental timing of power application to coincide to a peak or valley in the AC sine wave. - Few of these customarily being enuf to cause a problem, but perhaps in concert with with a small change in reactive resistance[impedance] they become a telling factor.

I still remember when I was young, my father getting our well pump to start from a 1.5kW emergency generator by lifting the extension cord off the ground. That was repeatable. We never investigated the medium of action tho.
larry

 

[Skyco]

Early in this thread it was mentioned some don't like Crescent Wrenches. Did you know there is a right and a wrong direction to apply high torque with a Crescent Wrench? Maybe that is the reason for some of the problems with them slipping or rounding off a fastener, the force should be applied so the contact point on the moveable jaw is on the side close to the handle, not out on the end where it can flex more. The fixed side can take the force out on the end of the jaw better

Another tip for difficult to remove screws where the driver is slipping is to put some valve grinding compound in the slot or recess. There is actually a commercial product for this, I think it is called Screw Medic, and it gives lots more traction to get it loose.

 

[Egon]

Here I though crescent wrench was just another name for hammer!!

 

[Soundguy]

A drop of superglue helps with a stripping screw as well..

Soundguy

 

[BobRip]

Was it one of those spring wind reels? They have brushes that may have just needed a jiggle to make better contact. It would be interesting to repeat the experiment. larry

I don't think it had brushes, but I am not sure. It was in Japan, and would be hard to repeat. My memory says that the outlet turned with the reel. So no brushes. It was not like the reel for my trouble light in the garage.

 

[cityfarma]

Early in this thread it was mentioned some don't like Crescent Wrenches. Did you know there is a right and a wrong direction to apply high torque with a Crescent Wrench? Maybe that is the reason for some of the problems with them slipping or rounding off a fastener, the force should be applied so the contact point on the moveable jaw is on the side close to the handle, not out on the end where it can flex more. The fixed side can take the force out on the end of the jaw better

Another tip for difficult to remove screws where the driver is slipping is to put some valve grinding compound in the slot or recess. There is actually a commercial product for this, I think it is called Screw Medic, and it gives lots more traction to get it loose.

Just because I'm a pedantic sod....

This works the same on all "adjustable wrenches" not just Crescent. As with many daily used objects, a brand has been associated with the object. Eg, Biro for pen.

Many times I have been asked to lend someone a phillips screwdriver and have had to decline as I did not have one. I did however had a pozidrive. Some may think they are interchangable. They are not. As it is possible to use some imperial sockets on some metric bolts, it can sometimes work. On inspection you will see that the phillips driver has tapered flutes whereas the pozidrive has parallel flutes. If you use a phillips driver in a pozidrive screw, you are likely to damage the head as you are only making contact on a very small area. Also the taper acts as a ramp and forces the driver out of the head and so requires more force to keep it in the slot.


Most electronic equipment these days that use a crosshead screw, are pozidrive.

Cityfarma

 

[Egon]

Is it safe to say "A Spanner may be using using an adjustable wrench in an inappropriate way" ?

 

[patrick_g]

Early in this thread it was mentioned some don't like Crescent Wrenches. Did you know there is a right and a wrong direction to apply high torque with a Crescent Wrench? Maybe that is the reason for some of the problems with them slipping or rounding off a fastener, the force should be applied so the contact point on the moveable jaw is on the side close to the handle, not out on the end where it can flex more. The fixed side can take the force out on the end of the jaw better

Said another way, always apply force to a Crescent wrench so that the intended direction of motion is toward the movable side. That is the way I was taught in the USAF.

Depending on the quality of the wrench, there may be other reasons for rounding off bolt heads and nuts. The good old Sears Craftsman crescent wrench had thicker and heavier jaws by a good margin over the actual Crescent brand wrench and the Craftsman opened up less than the Crescent brand. The Craftsman was made of soft steel and the wrench weighed nearly twice as much as the Crescent.

I had one of each in the 8 inch size. The Crescent brand was superior in every respect. The Craftsman's jaws soon got gouged when the tool flexed enough to let it turn while tightened on a bolt head as tight as it could be adjusted. I never gouged (hardly nicked) the jaws of the Crescent brand. The Crescent brand opened up wider so it could be used on larger bolts and was lighter so won a place in my tool belt when I retired the Craftsman to the bench for jobs within its capability.

Egon's "hammer" comment is most appropriately applied to the Craftsman brand crescent wrench. Of the HF and Cumins tools (a couple of cheap Chinese brands) I have bought, I find the quality to be intermediate to the Crescent and Craftsman.

The Craftsman is made of soft steel and was made heavier in dimensioin to off set that cost cutting measure. Opening less also helped prevent the tool from being returned for a free exchange.

Pat