Today's Message Index:
----------------------
1. 08:51 AM - Re: why put baffle seals outside the baffle (flyv35b)
2. 10:05 AM - Re: Oil Cooler Setback (923te)
3. 12:28 PM - Re: why put baffle seals outside the baffle (Gary Vogt)
4. 12:33 PM - Re: Oil Cooler Setback (Gary Vogt)
5. 12:55 PM - engine thrust angle (Gary Vogt)
6. 01:27 PM - Re: engine thrust angle (923te)
7. 01:34 PM - Re: why put baffle seals outside the baffle (Michael W. Meyer)
8. 01:36 PM - Re: Oil Cooler Setback (923te)
Message 1
| INDEX | Back to Main INDEX |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: why put baffle seals outside the baffle |
I believe that a good installation can be done either way. I've seen
baffles that were installed incorrectly from the back side that were cut
by the sharp edge of the metal baffle, probably because there wasn't
enough clearance between it and the cowling.
Here are 3 photos of what is a totally different arrangement than what
has been discussed, albeit not on a Grumman. Note that in the photo
(P1060256) of the front side that a top metal strip is riveted to a
flange and it sandwiches the seal material, forcing it to bend forward
and form a nice curvature.
The last photo (P106057) shows the oil cooler installation on the
opposite, LH side where the cooler is set back about 1.5 inches behind
the cylinder fins for improved air entrance flow. I think the Tiger
cooler could benefit from this sort of thing, although it wouldn't need
to be set back nearly as far.
Cliff
On 7/6/2011 8:33 PM, Gary Vogt wrote:
> Barry,
>
> I would challenge any installation you could do with what I do regarding
> longevity, sealing ability, and looks compared to mine. Inside is just
> not right.
>
> ------------------------------------------------------------------------
> *From:* FLYaDIVE <flyadive@gmail.com>
> *To:* teamgrumman-list@matronics.com
> *Sent:* Wed, July 6, 2011 6:44:29 PM
> *Subject:* Re: TeamGrumman-List: why put baffle seals outside the baffle
>
> Boris, Gary & Team:
>
> Here are my thoughts on In Vs Out:
>
> 1. There is no advantage of putting the silicon baffle material on
> the outside. Only a disadvantage.
> * Why? Well if you think about it there is only 0.025 to
> 0.035" difference in position between inside and out. The
> thickness of the metal baffle.
> * The difference is in which direction the NATURAL ROLL of the
> silicon goes. YOU MUST place the curve of the silicon baffle
> material to the INSIDE. This is true for BOTH the LENGTH and
> the WIDTH of the silicon baffle material.
> * THERE IS A CURVE! ! !
> * It's ugly! But beauty is in the eye of the beholder.
> 2. Reinforced Vs Un-Reinforced:
> * The Un-Reinforced is softer and will bend easier and conform
> easier.
> * The Un-Reinforced will also deform easier when the
> Pop-Rivets are squeezed down. This causes and adds to the
> scalloping of the silicon baffle material.
> * The Un-Reinforced will tear easier.
> 3. The Cure for problems in #2 above:
> * I use 1/8" thick x 1/2" wide x Required LONG LENGTHS of
> aluminum strips that function as a CONTINUOUS WASHER to hold
> down the silicon baffle material against the aluminum baffle
> material.
> * This FLATTENS the silicon baffle material ELIMINATING ALL
> scalloping as well as stiffening the aluminium baffle material.
> * So NOW you can use the softer, more flexible Non-Reinforced
> silicon baffle material. Which will give you a better seal
> and less ware.
> * So, why on the inside if you do all the above? It LQQKs a
> hell of a lot better.
> * Yes, you can still use the LONG LENGTHS of aluminum strips
> that function as a CONTINUOUS WASHER to hold down the
> silicon baffle material against the aluminum baffle material
> - On The Out Side.
> * Oh! I use 5/8" Dia HEAD x 1/8" Dia Shank x 1/2" Long Shank -
> Pop-Rivets.
> * To prevent tearing I stitch the over laps in the corners and
> 'V' cuts with dental floss.
>
> Barry
>
>
> On Wed, Jul 6, 2011 at 12:43 PM, b v <bvnj@yahoo.com
> <mailto:bvnj@yahoo.com>> wrote:
>
> <mailto:bvnj@yahoo.com>>
>
> Gary and all,
>
>
> A number of people suggest that if you put seals on the inside, the
> air pressure pushes them against the baffles and provides a better
> seal, while if you put them outside, the air will try to escape
> between the rivets.
>
> So what are the reasons to put the baffle seals on the outside of
> the cylinder and rear baffles?
>
> Thank you,
> -Boris
>
> ==========
> List"
> target="_blank">http://www.matronics.com/Navigator?TeamGrumman-List
> ==========
> http://forums.matronics.com
> ==========
> le, List Admin.
> ="_blank">http://www.matronics.com/contribution
> ==========
>
>
> *
>
>
> *
>
> *
>
>
> *
Message 2
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Oil Cooler Setback |
Hi Cliff,
I've experimented with airflow at the oil cooler on my Tiger. I found
that it is not intuitive. That is the airflow there must be complicated.
I have tried a deflector like Gary and others have used in front of the
cooler. I have also spaced the cooler back in increments up to about
3/4". None of these provided better oil cooling than the factory
location for me. The set back did not work at all and made the oil
hotter. The deflector could be shaped to help but made the rear cylinder
hotter.
I was quite "baffled" by these experiments as nothing seemed to work
like I thought it would. I returned it to the factory position. I must
say that changing one thing has a domino effect on the cooling of other
things. Like I mentioned yesterday moving the front baffle on the front
cylinders just a sixteenth of an inch up or down makes a big difference
in CHT spreads. And I found it to be different in summer than in winter.
So there are compromises. An easy way to experiment with this is to put
aluminum tape in front of the cylinders just above the factory baffle.
You can find the optimum position this way.
I would like to do what Gene Plazak has done and like a lot of RV
builders do and use a plenum over the cylinders instead of the factory
baffle system. Gary's baffles are a huge improvement over the factory
baffles. but the whole concept of these type of baffles is lacking I
think. A whole paradigm shift might be to use a plenum design. Plazak
got his approved on a one time basis but it might be really hard to do
that for an STC these days.
One example I'd like to try is the way Jabiru has tackled it as shown
here: http://www.usjabiru.com/images/pdf/AirDuctInstall.pdf
Then there is the air exits that should be 7:1 like Dave Anders RV4
instead of 15:1 ramp slope like Tigers are.....
ned
Message 3
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: why put baffle seals outside the baffle |
I did my Citabria, which has baffles that are not that different from those
on a =0ABonanza, using my technique. I used 1/4 as much hardware and acco
mplished the =0Asame thing. The Citabria had baffle seals mounted on the i
nside. I copied =0Athem. By the time I was done, I wished I'd done them
differently. Still, it =0Aworked OK.=0A=0AI've included a few pics. =0A
=A2 The first one is a customer I did a few years ago. This is how t
he baffle =0Alays over without any help. =0A=A2The next several pics
are of an installation where the metal baffle was =0Adeformed to make the
baffles fit. It's a brute force method that is really ugly =0Aand makes ma
intenance difficult. =0A=A2The next two are of my Citabria. =0A
=A2The last one is of an installation of a LoPresti nosebowl. Notice th
e gap in =0Athe corner. There is no way to elegantly fill this gap. Unles
s the installer =0Aknows what he's doing, CHTs will be higher after install
ing a LoPresti nosebowl.=0A=0A=0A=0A________________________________=0AFrom
: flyv35b <flyv35b@minetfiber.com>=0ATo: teamgrumman-list@matronics.com=0AS
ent: Thu, July 7, 2011 8:47:35 AM=0ASubject: Re: TeamGrumman-List: why put
baffle seals outside the baffle=0A=0AI believe that a good installation can
be done either way. I've seen =0Abaffles that were installed incorrectly
from the back side that were cut =0Aby the sharp edge of the metal baffle,
probably because there wasn't =0Aenough clearance between it and the cowlin
g.=0A=0AHere are 3 photos of what is a totally different arrangement than w
hat =0Ahas been discussed, albeit not on a Grumman. Note that in the photo
=0A(P1060256) of the front side that a top metal strip is riveted to a =0A
flange and it sandwiches the seal material, forcing it to bend forward =0Aa
nd form a nice curvature.=0A=0AThe last photo (P106057) shows the oil coole
r installation on the =0Aopposite, LH side where the cooler is set back abo
ut 1.5 inches behind =0Athe cylinder fins for improved air entrance flow.
I think the Tiger =0Acooler could benefit from this sort of thing, although
it wouldn't need =0Ato be set back nearly as far.=0A=0ACliff=0A=0AOn 7/6/2
011 8:33 PM, Gary Vogt wrote:=0A> Barry,=0A>=0A> I would challenge any inst
allation you could do with what I do regarding=0A> longevity, sealing abili
ty, and looks compared to mine. Inside is just=0A> not right.=0A>=0A> -----
-------------------------------------------------------------------=0A> *Fr
om:* FLYaDIVE <flyadive@gmail.com>=0A> *To:* teamgrumman-list@matronics.com
=0A> *Sent:* Wed, July 6, 2011 6:44:29 PM=0A> *Subject:* Re: TeamGrumman-Li
st: why put baffle seals outside the baffle=0A>=0A> Boris, Gary & Team:=0A>
=0A> Here are my thoughts on In Vs Out:=0A>=0A> 1. There is no advantage
of putting the silicon baffle material on=0A> the outside. Only a di
sadvantage.=0A> * Why? Well if you think about it there is only 0
.025 to=0A> 0.035" difference in position between inside and ou
t. The=0A> thickness of the metal baffle.=0A> * The d
ifference is in which direction the NATURAL ROLL of the=0A> sil
icon goes. YOU MUST place the curve of the silicon baffle=0A> m
aterial to the INSIDE. This is true for BOTH the LENGTH and=0A>
the WIDTH of the silicon baffle material.=0A> * THERE IS A CURVE
! ! !=0A> * It's ugly! But beauty is in the eye of the beholder.
=0A> 2. Reinforced Vs Un-Reinforced:=0A> * The Un-Reinforced i
s softer and will bend easier and conform=0A> easier.=0A>
* The Un-Reinforced will also deform easier when the=0A> P
op-Rivets are squeezed down. This causes and adds to the=0A> sc
alloping of the silicon baffle material.=0A> * The Un-Reinforced
will tear easier.=0A> 3. The Cure for problems in #2 above:=0A>
* I use 1/8" thick x 1/2" wide x Required LONG LENGTHS of=0A>
aluminum strips that function as a CONTINUOUS WASHER to hold=0A>
down the silicon baffle material against the aluminum baffle=0A>
material.=0A> * This FLATTENS the silicon baffle material EL
IMINATING ALL=0A> scalloping as well as stiffening the aluminiu
m baffle material.=0A> * So NOW you can use the softer, more flex
ible Non-Reinforced=0A> silicon baffle material. Which will giv
e you a better seal=0A> and less ware.=0A> * So, why
on the inside if you do all the above? It LQQKs a=0A> hell of a
lot better.=0A> * Yes, you can still use the LONG LENGTHS of alu
minum strips=0A> that function as a CONTINUOUS WASHER to hold d
own the=0A> silicon baffle material against the aluminum baffle
material=0A> - On The Out Side.=0A> * Oh! I use 5/8"
Dia HEAD x 1/8" Dia Shank x 1/2" Long Shank -=0A> Pop-Rivets.
=0A> * To prevent tearing I stitch the over laps in the corners a
nd=0A> 'V' cuts with dental floss.=0A>=0A> Barry=0A>=0A>=0A> On
Wed, Jul 6, 2011 at 12:43 PM, b v <bvnj@yahoo.com=0A> <mailto:bvnj@yahoo.c
ahoo.com=0A> <mailto:bvnj@yahoo.com>>=0A>=0A> Gary and all,=0A>=0A>
=0A> A number of people suggest that if you put seals on the inside, th
e=0A> air pressure pushes them against the baffles and provides a bette
r=0A> seal, while if you put them outside, the air will try to escape
=0A> between the rivets.=0A>=0A> So what are the reasons to put the
baffle seals on the outside of=0A> the cylinder and rear baffles?=0A>
=0A> Thank you,=0A> -Boris=0A>=0A> =========
===0A> List"=0A> target="_blank">http://www.matronics.com/Nav
igator?TeamGrumman-List=0A> ============0A> ht
tp://forums.matronics.com=0A> ============0A>
le, List Admin.=0A> ="_blank">http://www.matronics.com/contribution
=0A> ============0A>=0A>=0A>=0A>=0A> *=0A>=0A>=0A
> *=0A>=0A> *=0A>=0A>=0A> *=0A
Message 4
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Oil Cooler Setback |
I ran into Dave Anders in Visalia a number of years back. Trust me, I started
thinking of ways to cut up the floor of the Tiger.
I also tried fooling with the oil cooler. That's how I came up with mounting it
to the outside like on the Jaguar baffles.
The ramps in front of the cylinders "Like I mentioned yesterday moving the front
baffle on the front cylinders just a sixteenth of an inch up or down makes a big
difference in CHT spreads." are very dependent on angle of attack also. Setting
one up to cool during climb hurts CHT spread in cruise and vise versa.
________________________________
From: 923te <923te@att.net>
Sent: Thu, July 7, 2011 10:03:57 AM
Subject: Re: TeamGrumman-List: Oil Cooler Setback
Hi Cliff,
I've experimented with airflow at the oil cooler on my Tiger. I found that it
is not intuitive. That is the airflow there must be complicated. I have tried
a
deflector like Gary and others have used in front of the cooler. I have also
spaced the cooler back in increments up to about 3/4". None of these provided
better oil cooling than the factory location for me. The set back did not work
at all and made the oil hotter. The deflector could be shaped to help but made
the rear cylinder hotter.
I was quite "baffled" by these experiments as nothing seemed to work like I
thought it would. I returned it to the factory position. I must say that
changing one thing has a domino effect on the cooling of other things. Like I
mentioned yesterday moving the front baffle on the front cylinders just a
sixteenth of an inch up or down makes a big difference in CHT spreads. And I
found it to be different in summer than in winter. So there are compromises. An
easy way to experiment with this is to put aluminum tape in front of the
cylinders just above the factory baffle. You can find the optimum position this
way.
I would like to do what Gene Plazak has done and like a lot of RV builders do
and use a plenum over the cylinders instead of the factory baffle system.
Gary's baffles are a huge improvement over the factory baffles. but the whole
concept of these type of baffles is lacking I think. A whole paradigm shift
might be to use a plenum design. Plazak got his approved on a one time
basis but it might be really hard to do that for an STC these days.
One example I'd like to try is the way Jabiru has tackled it as shown here:
http://www.usjabiru.com/images/pdf/AirDuctInstall.pdf
Then there is the air exits that should be 7:1 like Dave Anders RV4 instead of
15:1 ramp slope like Tigers are.....
ned
Message 5
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | engine thrust angle |
doing an annual on a 2004 Tiger.
measured the engine thrust angle: + 0.2 degrees.
Could be Ned's is up too.
>From what I've found on the internet, down thrust is better
Message 6
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: engine thrust angle |
After tightening the engine mount bolts on my Tiger the thrust angle is
the same as the canopy rails which I take to be zero.
I measured this with a digital level like you do and both sides are the
same.
Message 7
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: why put baffle seals outside the baffle |
Hmmm... I believe that I recognize that engine compartment.
Gary replaced my baffles, with new metal parts, and flexible material as
he describes. It is definitely easier to access the plugs now - you can
see on the old baffles how the top edge was deformed from getting the
socket wrench in and out.
All the cylinders cool well in cruise and climb with the new baffles
(actually, I didn't have any cooling problems with the old ones either,
but they were old and tired, and needed to be replaced).
Thanks,
Michael
Michael W. Meyer
Tiger N74086
San Francisco, CA
michael@flightsked.com
On Jul 7, 2011, at 12:23 PM, Gary Vogt wrote:
> I did my Citabria, which has baffles that are not that different from
those on a Bonanza, using my technique. I used 1/4 as much hardware and
accomplished the same thing. The Citabria had baffle seals mounted on
the inside. I copied them. By the time I was done, I wished I'd done
them differently. Still, it worked OK.
>
> I've included a few pics.
> - The first one is a customer I did a few years ago. This is how
the baffle lays over without any help.
> -The next several pics are of an installation where the metal baffle
was deformed to make the baffles fit. It's a brute force method that is
really ugly and makes maintenance difficult.
> -The next two are of my Citabria.
> -The last one is of an installation of a LoPresti nosebowl. Notice
the gap in the corner. There is no way to elegantly fill this gap.
Unless the installer knows what he's doing, CHTs will be higher after
installing a LoPresti nosebowl.
>
> From: flyv35b <flyv35b@minetfiber.com>
> To: teamgrumman-list@matronics.com
> Sent: Thu, July 7, 2011 8:47:35 AM
> Subject: Re: TeamGrumman-List: why put baffle seals outside the baffle
>
> I believe that a good installation can be done either way. I've seen
> baffles that were installed incorrectly from the back side that were
cut
> by the sharp edge of the metal baffle, probably because there wasn't
> enough clearance between it and the cowling.
>
> Here are 3 photos of what is a totally different arrangement than what
> has been discussed, albeit not on a Grumman. Note that in the photo
> (P1060256) of the front side that a top metal strip is riveted to a
> flange and it sandwiches the seal material, forcing it to bend forward
> and form a nice curvature.
>
> The last photo (P106057) shows the oil cooler installation on the
> opposite, LH side where the cooler is set back about 1.5 inches behind
> the cylinder fins for improved air entrance flow. I think the Tiger
> cooler could benefit from this sort of thing, although it wouldn't
need
> to be set back nearly as far.
>
> Cliff
>
> On 7/6/2011 8:33 PM, Gary Vogt wrote:
> > Barry,
> >
> > I would challenge any installation you could do with what I do
regarding
> > longevity, sealing ability, and looks compared to mine. Inside is
just
> > not right.
> >
> >
------------------------------------------------------------------------
> > *From:* FLYaDIVE <flyadive@gmail.com>
> > *To:* teamgrumman-list@matronics.com
> > *Sent:* Wed, July 6, 2011 6:44:29 PM
> > *Subject:* Re: TeamGrumman-List: why put baffle seals outside the
baffle
> >
> > Boris, Gary & Team:
> >
> > Here are my thoughts on In Vs Out:
> >
> > 1. There is no advantage of putting the silicon baffle material
on
> > the outside. Only a disadvantage.
> > * Why? Well if you think about it there is only 0.025 to
> > 0.035" difference in position between inside and out. The
> > thickness of the metal baffle.
> > * The difference is in which direction the NATURAL ROLL of
the
> > silicon goes. YOU MUST place the curve of the silicon
baffle
> > material to the INSIDE. This is true for BOTH the LENGTH
and
> > the WIDTH of the silicon baffle material.
> > * THERE IS A CURVE! ! !
> > * It's ugly! But beauty is in the eye of the beholder.
> > 2. Reinforced Vs Un-Reinforced:
> > * The Un-Reinforced is softer and will bend easier and
conform
> > easier.
> > * The Un-Reinforced will also deform easier when the
> > Pop-Rivets are squeezed down. This causes and adds to the
> > scalloping of the silicon baffle material.
> > * The Un-Reinforced will tear easier.
> > 3. The Cure for problems in #2 above:
> > * I use 1/8" thick x 1/2" wide x Required LONG LENGTHS of
> > aluminum strips that function as a CONTINUOUS WASHER to
hold
> > down the silicon baffle material against the aluminum
baffle
> > material.
> > * This FLATTENS the silicon baffle material ELIMINATING ALL
> > scalloping as well as stiffening the aluminium baffle
material.
> > * So NOW you can use the softer, more flexible
Non-Reinforced
> > silicon baffle material. Which will give you a better
seal
> > and less ware.
> > * So, why on the inside if you do all the above? It LQQKs a
> > hell of a lot better.
> > * Yes, you can still use the LONG LENGTHS of aluminum
strips
> > that function as a CONTINUOUS WASHER to hold down the
> > silicon baffle material against the aluminum baffle
material
> > - On The Out Side.
> > * Oh! I use 5/8" Dia HEAD x 1/8" Dia Shank x 1/2" Long
Shank -
> > Pop-Rivets.
> > * To prevent tearing I stitch the over laps in the corners
and
> > 'V' cuts with dental floss.
> >
> > Barry
> >
> >
> > On Wed, Jul 6, 2011 at 12:43 PM, b v <bvnj@yahoo.com
> > <mailto:bvnj@yahoo.com>> wrote:
> >
> > <mailto:bvnj@yahoo.com>>
> >
> > Gary and all,
> >
> >
> > A number of people suggest that if you put seals on the inside,
the
> > air pressure pushes them against the baffles and provides a
better
> > seal, while if you put them outside, the air will try to escape
> > between the rivets.
> >
> > So what are the reasons to put the baffle seals on the outside of
> > the cylinder and rear baffles?
> >
> > Thank you,
> > -Boris
> >
> > ==========
> > List"
> >
target="_blank">http://www.matronics.com/Navigator?TeamGrumman-List
> > ==========
> > http://forums.matronics.com
> > ==========
> > le, List Admin.
> > ="_blank">http://www.matronics.com/contribution
> > ==========
> >
> >
> >
> >
> > *
> >
> >
> > *
> >
> > *
> >
> >
> > *
>
<Baffles_18.jpg><BafflesNot_01.jpg><BafflesNot_02.jpg><BafflesNot_03.jpg><
BafflesNot_04.jpg><BafflesNot_05.jpg><BafflesNot_06.jpg><BafflesNot_07.jpg
><CitabriaEngine_Lt.jpg><CitabriaEngine_Rt.jpg><10-2003 050.jpg>
Message 8
| INDEX | Back to Main INDEX |
| PREVIOUS | Skip to PREVIOUS Message |
| NEXT | Skip to NEXT Message |
| LIST | Reply to LIST Regarding this Message |
| SENDER | Reply to SENDER Regarding this Message |
|
| Subject: | Re: Oil Cooler Setback |
Putting the exit ramp into the floor would be optimal. I was thinking
that adding to the bottom with a fiberglass fairing might work. It would
increase frontal area thus drag. Both the cowl and fuselage would have
to be lowered with a fairing to get the proper NACA duct installed. I
think it would be around 23" long
It would be great to place the exhaust into the NACA and try and get
some "augmentor" effect...
It would be interesting to see which was geater, drag from increased
frontal area or less cooling drag from a better NACA exit design.
Other Matronics Email List Services
These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.
-- Please support this service by making your Contribution today! --
|