worm drive saw

[ajax]

People,

Pardon my ignorance - what is a worm drive saw ? is it like a circular saw ? Can it be used instead of a circular saw ! Please enlighten.

Thanks n cheers

[Eastie]

Circular saws come in two types - worm-drive and sidewinder.

Unlike the side winder models where the motor sits alongside the blade, worm-drive saws have motors positioned parallel to the blade and use a worm gear transmission with huge gearing that substantially increases torque at the cost of a little bit of blade speed.
When looking at saws worm drives usually have the handle set way back behind the saw, unlike normal circular saws where the handle is almost alongside the blade.

From what I've seen worm drives are still at the top end of the market being for professional day to day use.

[soundman]

or perhaps a worm drive saw could be a slower but more practical idea than the battery saw.


But how long do the worms last, can they be re charged and what is the best type to use? Are african night crawlers ok?

[JohnM]

Maybe a glow-worm could be used like a laser guide!!





Sorry, couldn't stop myself

[ajax]

Eastie, Thanks for the info. Sorry for the late reply - I was away.

[Eastie]

Soundman & John,

From a little bit of investigation of this here interweb thing I’ve managed to uncover some info I thought you would appreciate. According to the US Navy, unlike the worm driven saw the sidewinder is a totally different beast. Firstly, it has a infrared heat-seeking guidance system complimenting an active optical target detector. All this is strapped on to a solid fuel rocket motor, giving it great acceleration and a velocity in the range of mach 2.5. The Navy market this product as a true example of a search-and-destroy machine – but I guess most wives say that about their husbands and their power tools. There were no details on how you would start the saw before the guidance system to allow the blade to get up sufficient speed – I’m sure someone has thought of this though? Anyhow, the infra red guidance system, although it might seem impractical for a saw, is actually advantageous as infrared units cost less than other types of guidance systems and can be used day or night in all weather conditions – a real plus for the tradesman. According to the Navy the infrared seeker also permits the tool operator to launch the unit then leave the area or take evasive action while the unit guides itself to the target.

There was also a lack of information on exactly how you get the saw to guide itself along a piece of wood (aka the target), as the infra red would need some form of heat – I guess that’s why the recommend evasive action on the part of the operator. It seems that to get the most out of this saw you would really need to have a bit of a fiddle with an electric fence unit and lay a hot wire along the line of cut ? Regardless of what would be called minor drawbacks this has great advantages over the worm driven model, which is only capable of a velocity of approximately 10 cm per minute, a feed rate that is proportionately as silly as that of the sidewinder.
In addition, the sidewinder has the added feature of being a more than capable demolition saw with room in the nose for a significant payload of high explosives.
(they started it :D)

[soundman]

ok eastie you win the silly prise this week.