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RapidSlide Adjustable Wrench

mechanomy.com

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Re: RapidSlide Adjustable Wrench

#101

Post by 83 »

Looking more closely, the slider screw has a pitch of approximately 0.545"/rev and a diameter of 0.25", for a helix angle of 34°. This means that less than half of the slider force is actually used to turn the screw, undermining any force gain. That is, the jaw force is less than is applied to the slider due to the screw's inefficiency as over half of the applied force is lost pushing against the screw's supports.

Is that accurate that over half the force is lost? As the helix angle gets lower wouldn't more force be transferred to the screw instead of the supports? I'm no mechanical engineer but my gut says 45 degrees would be the point where forces are balanced between screw and support and as the helix angle decreased (to 34 degrees for example) more than half the force would be applied to the screw.

Re: RapidSlide Adjustable Wrench

#102

Post by staticautomatic »

mauvehaus wrote: post #27

I haven't yet run across an adjustable wrench that was worth a shit. Even old (notionally decent?) Crescent ones. The jaws invariably splay when you apply force, even if you're using them correctly. I've come to the conclusion that it's just intrinsic to having a moving jaw that moves easily enough to be useful. At this point, if I expect to need the wrench ever again (or need to reuse the fastener), I'll just buy a…

I wonder if you could have one with a device like a rock climbing cam that tightens the more force you put on it.

Re: RapidSlide Adjustable Wrench

#103

Post by snovv_crash »

83 wrote: post #101

Looking more closely, the slider screw has a pitch of approximately 0.545"/rev and a diameter of 0.25", for a helix angle of 34°. This means that less than half of the slider force is actually used to turn the screw, undermining any force gain. That is, the jaw force is less than is applied to the slider due to the screw's inefficiency as over half of the applied force is lost pushing against the screw's supports. Is…

Consider the friction coefficient between the two parts. If it slid perfectly, ie. both were made of greased teflon, then at 30 degrees half would be in the correct direction - sin30° = 0.5

However adding friction makes it much worse. Unlubricated steel on steel is really bad.

Re: RapidSlide Adjustable Wrench

#104

Post by kitd »

mauvehaus wrote: post #27

I haven't yet run across an adjustable wrench that was worth a shit. Even old (notionally decent?) Crescent ones. The jaws invariably splay when you apply force, even if you're using them correctly. I've come to the conclusion that it's just intrinsic to having a moving jaw that moves easily enough to be useful. At this point, if I expect to need the wrench ever again (or need to reuse the fastener), I'll just buy a…

Water-pump pliers are adjustable and don't suffer from splay.

Re: RapidSlide Adjustable Wrench

#105

Post by lbhdc »

mauvehaus wrote: post #27

I haven't yet run across an adjustable wrench that was worth a shit. Even old (notionally decent?) Crescent ones. The jaws invariably splay when you apply force, even if you're using them correctly. I've come to the conclusion that it's just intrinsic to having a moving jaw that moves easily enough to be useful. At this point, if I expect to need the wrench ever again (or need to reuse the fastener), I'll just buy a…

I feel like every crescent wrench I have tried wrecks fasteners. A good set of combo wrenches are so much nicer to work with.

Re: RapidSlide Adjustable Wrench

#106

Post by johnwalkr »

mauvehaus wrote: post #27

I haven't yet run across an adjustable wrench that was worth a shit. Even old (notionally decent?) Crescent ones. The jaws invariably splay when you apply force, even if you're using them correctly. I've come to the conclusion that it's just intrinsic to having a moving jaw that moves easily enough to be useful. At this point, if I expect to need the wrench ever again (or need to reuse the fastener), I'll just buy a…

I (and apparently many others) came here to knipex plier wrenches. The have a spring-loaded indent that keeps the adjustment where you need it, tighten on the fastener in one direction, and open enough to act as a ratchet in the other direction. In certain cases they are actually less likely to round off a fastener than a non-adjustable wrench. This[1] video gives a good overview.

[1]https://www.youtube.com/watch?v=vGb4WF4e8YQ

Re: RapidSlide Adjustable Wrench

#107

Post by Melatonic »

Knippex "Pliers" are still far superior to this. They blew my mind when I first used them. I dont use normal wrenches at all anymore - the knippex just grip stuff so much more perfectly and with less chance of rounding and you can "ratchet" around the bolt even though they are open ended.

Re: RapidSlide Adjustable Wrench

#108

Post by johnwalkr »

soared wrote: post #36
Eduardo3rd wrote: post #3

I've long subscribed to the philosophy that you should buy the cheapest tool you can find and use safely, use it until it wears out, breaks, or your skill surpasses the capability of the tool - and only then should you spend money on high quality tools. Too much money is thrown away in the name of "buy once, cry once" only to discover that you don't need the capabilities offered by the top of the line options.

Until you use a cheap tool on your expensive bike, the allowance on the tool is poor and strips a screw, which can only be custom ordered direct from the manufacturer with a 2 month lead time, leaving your half-fixed bike completely useless. This happened to me when bleeding my hydraulic brakes - the screw was a 2.5mm Allen and my keys were slightly smaller than 2.5 from being rounded over a short period of time. Tha…

I keep a handful of left-handed drill bits on hand for drilling out screws. You can get them cheaply from mcmaster. They work much better than "Easy-outs" and similar tools, and 90% of the time the fastener backs out well before you reach the point where you have to hope you're not damaging anything but the screw.

Re: RapidSlide Adjustable Wrench

#109

Post by edelans »

Melatonic wrote: post #107

Knippex "Pliers" are still far superior to this. They blew my mind when I first used them. I dont use normal wrenches at all anymore - the knippex just grip stuff so much more perfectly and with less chance of rounding and you can "ratchet" around the bolt even though they are open ended.

Same. I first saw them in the hands of a plumber doing some work at home. I bought a pair the same day. It's this kind of tool that just makes me happy when I have an occasion to use it.

Re: RapidSlide Adjustable Wrench

#110

Post by carterschonwald »

ls15 wrote: post #92
mauvehaus wrote: post #72

Earlier quoted context omitted.

I've heard a lot of recommendations for Knipex. I might yet break down and buy one of those even if it is a little bulky.

The mini version isn't bulky: https://www.knipex.com/products/pipe-wrenches-and-water-pump... A thing of beauty

love it
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