Woodwork Post

[Robatoy]

On Nov 20, 5:53 pm, Puckdropper wrote:
> -MIKE- wrote in news:gg45d0$krb$2
> @nntp.motzarella.org:
>
> > Lee Michaels wrote:
> >> That planer is good and all.  But.......,  where is the dust control
> >> system??
>
> > 5-10mph breeze.
>
> A cyclone would work better.
>
Oewww... I oughtta....

[B a r r y]

Robatoy wrote:
>
> I was trying to be funny... 10 HP with all that weight won't get you
> far, eh

Ahh!

No, but there have been diesels small enough to power r/c airplanes for
at least 15 years. They work really well in scale aircraft, as they
handle long exhaust extensions well, swing large props at a slower
speed, and have a more realistic sound.

>
> Btw, I have been reading a bit on diesel aircraft engines. They seem
> to have quite a following.

They had great promise, but Thielert, the biggest player, who based
theirs on a Mercedes turbo diesel, went BK. According to a podcast I
listened to a few weeks back, Thielert left far more orphans than I
would have guessed.

Since jet fuel is far more available worldwide than avgas, I thought it
was going to be big! I think the main reason for the lack of interest
in North America was the easy availability of avgas, and the
availability of a relatively easy 87 octane auto gas conversion for many
engines. Lots of guys who did the 87 conversion are now having problems
finding ethanol-free unleaded...

[J. Clarke]

B A R R Y wrote:
> Robatoy wrote:
>>
>> I was trying to be funny... 10 HP with all that weight won't get
>> you
>> far, eh
>
> Ahh!
>
> No, but there have been diesels small enough to power r/c airplanes
> for at least 15 years. They work really well in scale aircraft, as
> they handle long exhaust extensions well, swing large props at a
> slower speed, and have a more realistic sound.
>
>>
>> Btw, I have been reading a bit on diesel aircraft engines. They
>> seem
>> to have quite a following.
>
> They had great promise, but Thielert, the biggest player, who based
> theirs on a Mercedes turbo diesel, went BK. According to a podcast
> I
> listened to a few weeks back, Thielert left far more orphans than I
> would have guessed.
>
> Since jet fuel is far more available worldwide than avgas, I thought
> it was going to be big! I think the main reason for the lack of
> interest in North America was the easy availability of avgas, and
> the
> availability of a relatively easy 87 octane auto gas conversion for
> many engines. Lots of guys who did the 87 conversion are now having
> problems finding ethanol-free unleaded...

I suspect that ultimately a multifuel engine would be a more fruitful
approach, and small multifuel reciprocating engines do exist--the Army
used them on trucks a while back and Evinrude has a multifuel
two-cycle outboard. Don't know how the Army does it but Evinrude uses
direct injection like a diesel but with relatively low compression (by
diesel standards) and a spark plug.

--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

[Morris Dovey]

J. Clarke wrote:
> B A R R Y wrote:
>> Robatoy wrote:

>>> Btw, I have been reading a bit on diesel aircraft engines. They
>>> seem
>>> to have quite a following.
>> They had great promise, but Thielert, the biggest player, who based
>> theirs on a Mercedes turbo diesel, went BK. According to a podcast
>> I
>> listened to a few weeks back, Thielert left far more orphans than I
>> would have guessed.
>>
>> Since jet fuel is far more available worldwide than avgas, I thought
>> it was going to be big! I think the main reason for the lack of
>> interest in North America was the easy availability of avgas, and
>> the
>> availability of a relatively easy 87 octane auto gas conversion for
>> many engines. Lots of guys who did the 87 conversion are now having
>> problems finding ethanol-free unleaded...
>
> I suspect that ultimately a multifuel engine would be a more fruitful
> approach, and small multifuel reciprocating engines do exist--the Army
> used them on trucks a while back and Evinrude has a multifuel
> two-cycle outboard. Don't know how the Army does it but Evinrude uses
> direct injection like a diesel but with relatively low compression (by
> diesel standards) and a spark plug.

Hmm - In my ignorance, I have to wonder how well a low compression
engine would fare at 8000'/2400m. Would that work?

(I played with diesel model aircraft engines in the 50's, but they ran
at fairly high compression.)

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/

[Robatoy]

On Nov 21, 9:55 am, Morris Dovey wrote:
> J. Clarke wrote:
> > B A R R Y wrote:
> >> Robatoy wrote:
> >>> Btw, I have been reading a bit on diesel aircraft engines. They
> >>> seem
> >>> to have quite a following.
> >> They had great promise, but Thielert, the biggest player, who based
> >> theirs on a Mercedes turbo diesel, went BK.  According to a podcast
> >> I
> >> listened to a few weeks back, Thielert left far more orphans than I
> >> would have guessed.
>
> >> Since jet fuel is far more available worldwide than avgas, I thought
> >> it was going to be big!  I think the main reason for the lack of
> >> interest in North America was the easy availability of avgas, and
> >> the
> >> availability of a relatively easy 87 octane auto gas conversion for
> >> many engines.  Lots of guys who did the 87 conversion are now having
> >> problems finding ethanol-free unleaded...
>
> > I suspect that ultimately a multifuel engine would be a more fruitful
> > approach, and small multifuel reciprocating engines do exist--the Army
> > used them on trucks a while back and Evinrude has a multifuel
> > two-cycle outboard.  Don't know how the Army does it but Evinrude uses
> > direct injection like a diesel but with relatively low compression (by
> > diesel standards) and a spark plug.
>
> Hmm - In my ignorance, I have to wonder how well a low compression
> engine would fare at 8000'/2400m. Would that work?
>
That would be extra work... dragging that lumber up a mountain like
that?
What if you didn't have a mountain nearby?

[Morris Dovey]

Robatoy wrote:

> That would be extra work... dragging that lumber up a mountain like
> that?
> What if you didn't have a mountain nearby?

Then I'd probably need a little help from my friends.

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/

[J. Clarke]

Morris Dovey wrote:
> J. Clarke wrote:
>> B A R R Y wrote:
>>> Robatoy wrote:
>
>>>> Btw, I have been reading a bit on diesel aircraft engines. They
>>>> seem
>>>> to have quite a following.
>>> They had great promise, but Thielert, the biggest player, who
>>> based
>>> theirs on a Mercedes turbo diesel, went BK. According to a
>>> podcast
>>> I
>>> listened to a few weeks back, Thielert left far more orphans than
>>> I
>>> would have guessed.
>>>
>>> Since jet fuel is far more available worldwide than avgas, I
>>> thought
>>> it was going to be big! I think the main reason for the lack of
>>> interest in North America was the easy availability of avgas, and
>>> the
>>> availability of a relatively easy 87 octane auto gas conversion
>>> for
>>> many engines. Lots of guys who did the 87 conversion are now
>>> having
>>> problems finding ethanol-free unleaded...
>>
>> I suspect that ultimately a multifuel engine would be a more
>> fruitful
>> approach, and small multifuel reciprocating engines do exist--the
>> Army used them on trucks a while back and Evinrude has a multifuel
>> two-cycle outboard. Don't know how the Army does it but Evinrude
>> uses direct injection like a diesel but with relatively low
>> compression (by diesel standards) and a spark plug.
>
> Hmm - In my ignorance, I have to wonder how well a low compression
> engine would fare at 8000'/2400m. Would that work?

Diesels typically have compression ratios from 14:1 to 24:1. Few
gasoline engines go higher than 12:1 and most considerably less. The
Continental O-200 has 7:1, the Lycoming O-235 has 8.1:1. Both are
very popular aero engines that work fine at 8,000 feet. The
Rolls-Royce Merlin that powered the Spitfire had 6:1 but it also had a
blower.

> (I played with diesel model aircraft engines in the 50's, but they
> ran
> at fairly high compression.)

All diesels run at high compression--it's the nature of the beast that
they have to.

--
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)

[Morris Dovey]

J. Clarke wrote:
> Morris Dovey wrote:

>> Hmm - In my ignorance, I have to wonder how well a low compression
>> engine would fare at 8000'/2400m. Would that work?
>
> Diesels typically have compression ratios from 14:1 to 24:1. Few
> gasoline engines go higher than 12:1 and most considerably less. The
> Continental O-200 has 7:1, the Lycoming O-235 has 8.1:1. Both are
> very popular aero engines that work fine at 8,000 feet. The
> Rolls-Royce Merlin that powered the Spitfire had 6:1 but it also had a
> blower.
>
>> (I played with diesel model aircraft engines in the 50's, but they
>> ran at fairly high compression.)
>
> All diesels run at high compression--it's the nature of the beast that
> they have to.

Thanks, John. The mention of a low compression aircraft engine confused
me - I suppose a 14:1 might be a "low compression diesel" then, even
though that might be fairly high for a gas engine. IIRC, my old Volvo
B20 (gasoline) engine had a compression ratio of 11:1, which I was told
was fairly high for a car.

I appreciate the info.

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/

[Morris Dovey]

I checked with the optician who stripped and recoated my polycarbonate
glasses a while back and learned that that isn't being done any more
because the stripping process can produce ripples on the lens surface.

I asked about using windshield scratch filler/remover products and he
thought that /might/ work short-term, but would probably not survive
much lens cleaning.

--
Morris Dovey
DeSoto Solar
DeSoto, Iowa USA
http://www.iedu.com/DeSoto/