Winches (was Aerotow with Diesel engine?

I hit send by mistake before I was done writing...

There is a radius on the block where the rope enters the metal block. However,
at the junction of the block and the cylinder, both are left sharp edged. I
don't recall, but the cylinder may be bored out on the inside so there is
effectively a cutting edge.

This should work fine with spectra. I don't think an electrically heated blade
is the way to go because it takes time to heat the blade. When you want to use
a guillotine, you want to use it NOW!

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"Todd Pattist" wrote in message
.. .
illspam (Jim Vincent) wrote:
Here is a design that one of my friends designed tfor our club winch.
The
beauty of this design is that there is no chance of getting a finger cut
and it
works perfectly.

The design is based on a rotating cylinder mounted inside a metal cube.
The
metal cube has a hole drilled through it through the center line. The
cylinder
also has a hole drilled through it. In normal use, the hole in the cube
lines
up with the holein the cylinder. To activate, a handle rotates the
cylinder,
which the cylinder rotatesImagine an 8 inch square solid metal cube.

Spectra can be tough to cut. Are they using this design
with Spectra?
Todd Pattist - "WH" Ventus C
(Remove DONTSPAMME from address to email reply.)

Spectra cuts OK with a sharp edge but blunt steel cutters may have a problem
with it.

The stuff melts below 300F so the people who work with it regularly use hot
blade knives to cut it. It shouldn't be too hard to make a guillotine with
an electrically heated blade.

Bill Daniels



Jim Vincent
N483SZ
illspam

"Jim Vincent" wrote in message
...
I hit send by mistake before I was done writing...

This should work fine with spectra. I don't think an electrically heated
blade
is the way to go because it takes time to heat the blade. When you want
to use
a guillotine, you want to use it NOW!


The more I think about it, the more I like the rotating cylinder in a block
idea . It's very robust, easy to make and the cutting edges are protected.
Sharpening the edges would just be a matter of using a cylinder hone in a
hand drill. The Spectra could be protected from the edges with a cut-able,
thin wall plastic tube inserted into the through-hole.

Bill Daniels

I put a quick and dirty diagram of the rotating guillotine on my website:

www.mymedtrans.com/personal.htm

After looking at the diagram, I realize there is no need to bore out the inside
of the barrel because when it rotates it presents a sharp cutting edge to the
rope.

My guess is that it would work just fine with Spectra.






Jim Vincent
N483SZ
illspam

I have to give Andrew Meads full credit for the design. We were all trying to
figure out a solution about five years ago and he came up with the best idea.
We were averse to using a hatchet or scissors.




The more I think about it, the more I like the rotating cylinder in a block
idea . It's very robust, easy to make and the cutting edges are protected.
Sharpening the edges would just be a matter of using a cylinder hone in a
hand drill. The Spectra could be protected from the edges with a cut-able,
thin wall plastic tube inserted into the through-hole.

Bill Daniels



Jim Vincent
N483SZ
illspam

Better to use rotatating guides on bearings at the entrance and exit holes.
Plastic would burn through in no time at all.

The Spectra could be protected from the edges with a cut-able,
thin wall plastic tube inserted into the through-hole.



Jim Vincent
N483SZ
illspam

I didn't mean to use the guillotine in place guide rollers. With the
Spectra under tension, guide rollers should prevent it from touching the
guillotine.

However, a thin plastic tube would keep dirt and moisture out of the
guillotine block so it wouldn't rust or jam. It would also prevent the
Spectra from touching the steel edges when not under tension.

Bill Daniels

"Jim Vincent" wrote in message
...
Better to use rotatating guides on bearings at the entrance and exit
holes.
Plastic would burn through in no time at all.

The Spectra could be protected from the edges with a cut-able,
thin wall plastic tube inserted into the through-hole.



Jim Vincent
N483SZ
illspam

illspam (Jim Vincent) wrote in message ...
Here is a design that one of my friends designed tfor our club winch. The
beauty of this design is that there is no chance of getting a finger cut and it
works perfectly.

The design is based on a rotating cylinder mounted inside a metal cube. The
metal cube has a hole drilled through it through the center line. The cylinder
also has a hole drilled through it. In normal use, the hole in the cube lines
up with the holein the cylinder. To activate, a handle rotates the cylinder,
which the cylinder rotatesImagine an 8 inch square solid metal cube.


Great Idea, I bet driving the rotating cylinder/blade with a heavy duty
starter would make a very nice install. Sharp machined surfaces should
cut "Plasma Rope" cleanly although might not have enough energy to shear
wire. This may be just what I've been looking for. I'll never use wire
again anyway. Thanks Jim.

Craig-

To slightly change the direction of this thread, previous posts have
mentioned the use of Dyneema and Spectra cable for winch launching.
Are there any statistics yet to indicate useful life of such cable,
particularly in dry dusty conditions ?
Cheers, John G.

"John Giddy" wrote in message
...
To slightly change the direction of this thread, previous posts have
mentioned the use of Dyneema and Spectra cable for winch launching.
Are there any statistics yet to indicate useful life of such cable,
particularly in dry dusty conditions ?
Cheers, John G.

The stuff seems to be pretty immune to environmental conditions. It's
reported to be especially good for use on highly abrasive surfaces like
asphalt or concrete. The biggest hazards seem to be contact with hot winch
parts or sharp metal edges.

Several clubs in Germany are reporting 2000+ launches without a break. Most
people are now thinking that the higher cost of Spectra is offset by its
longer service life, 20% higher launches and the fact that it's much nicer
to work with than steel.

Bill Daniels

The cylinder only needs to rotate about 20-30 degrees.

We use a lever mounted to the end of the cylinder. The lever is attached to a
handle in the winch cabin with a cable. In normal position, the cylinder holes
are in line with the block. Pull the handle and the cylinder rotates.


Great Idea, I bet driving the rotating cylinder/blade with a heavy duty
starter would make a very nice install.



Jim Vincent
N483SZ
illspam