« An Engineer in Wonderland - Hmmm, LED headlamp flop? | Main | Only Connect: Molex and the Solar powered vehicle »

An Engineer in Wonderland - Wooden springs and infinite fretsaws

 

An Engineer in Wonderland has a new home. You can find this particular entry here. If you wish to leave a comment, please do that on the new blog.

 

Roof saw thumb.jpgI was talking to a retired wood worker about a bench-top scroll saw I just bought.

It is the mechanical cousin of the hand-held fret saw, and within it a saw blade under tension moves rapidly up and down cutting what ever you push against it.

The good thing is, by threading the blade through a drilled starter hole, apertures can be cut in sheet material.

Well that is the theory, but I am not getting on too well with it, which is why I approached the expert.

He gave me some tips, and then told me of the one that he used as a professional.

Rather than have an arm running from the base to the top of the blade, like mine has (see photo), the upper end of the blade in the big industrial version was suspended from the ceiling of the huge workshop by a long vertical wooden beam.

With no support arm in the way, any size sheets of wood could be sawn up.

And on one occasion, to get someone out of a hole, an aluminium car roof was slid underneath to cut window apertures.

Guy-wires from the beam to the roof held the support beam steady, and these had to adjusted a few millimetres twice a year, once as the girder-and-asbestos building warmed up in the spring, and again as it cooled in the winter.

At the bottom of the beam was a guided holder for the blade with tension provided by a leather strap connected to either end of a wooden - probably ash - bow spring.

Despite constant flexing at sawing speed by the electric motor in the base of the machine, the wooden spring never needed replacing.

'Alice'


Should you feel the need, respond to alice@electronicsweekly.com with 'saw' in the title.

You can also respond below, although our new super-zealous spam filter might discard you comment, but probably won't.

No email addresses are collected for marketing (or any other) purposes from responses to this blog. I will keep it that way for as long as possible.

Share |

TrackBack

TrackBack URL for this entry:
http://www.electronicsweekly.com/cgi-bin/mt/mt-tb.cgi/206863

Post a comment

(If you haven't left a comment here before, you may need to be approved by the site owner before your comment will appear. Until then, it won't appear on the entry. Thanks for waiting.)

About

This page contains a single entry from the blog posted on September 5, 2011 8:26 AM.

The previous post in this blog was An Engineer in Wonderland - Hmmm, LED headlamp flop?.

The next post in this blog is Only Connect: Molex and the Solar powered vehicle.

More posts can be found on the main index page or by looking through the archives.

Archives

Powered by
Movable Type 4.37