--- In hobbicast@y..., "chuckfellows" <chuckfellows@y...> wrote:
> How exactly would you scale it down? Does that include a smaller
> hole for the air jet?
> Chuck Fellows
I assume there was some experimentation involved in the development
of the original design to find the right balance between air and fuel
flow. Now, changing anything could change everything..I don't know,
but, it seems resonable that keeping the air to fuel jet ratio the
same would be a good plan to start with,. As such, if I do make
another one (and I probably will at some point) I would downsize both
the air and fuel (nozzle) jets equaly. The restriction to flow is a
function of area ,not diameter (though diameter obviously effects
surface area), so I wouldn't simply make the holes half the diameter.
Rather, I would reduce the hole size enough that the cross section
surface area was half the original cross section surface area. For
example, the 1/16" (.0625") air jet has a cross section area of .003"
(Area=Pi X R2), so you would need to figure the diameter that would
give a cross section of .0015".
As with all trips into uncharted territory, this is a "best guess"
approach..your mileage may vary.
> --- In hobbicast@y..., "scale_chipper" <scale_chipper@y...> wrote:
> > I'm starting to see some potential here. My second run yielded 22
> > pounds of ingots, and consumed 1 1/2 gallons of diesel..right at
> > the consumption of the first run and only 2 pounds less of Al.
> > last crucible was only half full.
> > I also discovered I was pouring too cold the first time. This
> > around I felt the heat through my leather protection gear on my
> > I decided to put a fuel valve inline with torch, but alas, the
> > hardware store was closed. Not to be thwarted by inconvienent
> > hours, I placed a small "C" clamp on the rubber fuel line, and
> > cranked 'er down till she just started sputtering, then backed
> > quarter turn. Not perfect but MUCH better. Not near as much soot,
> > much hotter flame, and twice the economy.
> > Tuning this thing reminded me of highschool (back when Heavy
> > ruled the road)when the less informed would put the biggest carb
> > could find on there cars. No matter how hard you tried, you could
> > never lean it out quite enough. Similarly ,I think in my case
> > that the torch is simply too large for my little 7"x 11" bore
> > Knowing what I know now, I would scale the original plans by
> > for the fuel valve , and leave the burner size the same.
> > I'll continue to keep this group informed of any new progress.
> > Casey Broen