[rebel-builders] Re: max tank vacuum

[Charlie Eubanks]

Hi Ron
I can't help you with the vacume it takes to damage your tank.I built a
Monometer out of 3/8 PVC clear tube mounted on a large piece of plywood with
14.5 and 20" above and below 0". Stuck my shop vac hose in the tank and
sealed it with duck tape. I was able to pull about 18" and the tank walls
really sucked in. You can regulate it some what by how well you seal the
duck tape. If the tank gets to looking to bad pull the plug on the shop vac.
Will send photo off line. Good luck. Let me know if successfull I may have t
o do it again.
Charlie E. 802R

----- Original Message -----
From: "Ron Shannon" <rshannon@cruzcom.com>
To: <rebel-builders@dcsol.com>
Sent: Tuesday, March 01, 2011 8:53 PM
Subject: [rebel-builders] Re: max tank vacuum

Golly, I was just kidding about the PS but, to show remorse & reform
anyway,
I've already (re)enrolled in the Rebel Builder's Etiquette & Ethics
Education Program (a.k.a. "RBEEEP"). ;-)

One person replied direct, conveying someone else's (anonymous)
quasi-formal
engineering analysis (with graphics I don't really understand) to the
effect
that a 1.5 PSI vacuum should not be feared. Has anyone actually had the
misfortune to crumple the tanks doing this?

Ron


On Tue, Mar 1, 2011 at 3:15 PM, Ron Shannon <rshannon@cruzcom.com> wrote:

So... I'm going after the fuel tank seepage again once again attempting
to
draw in Loctite 609 with negative tank pressure, as recommended by my EAA
Tech Advisor months ago. The seepage hasn't kept me from putting on 65+
hrs., but is a nuisance, and something I would like to correct before
painting, if possible. The first time I did this I used ~0.5 PSI of
vacuum,
as measured by a rather sticky, non-precision meter -- with not very
impressive results. This time I have fancier equipment, and am
contemplating
probably going to ~28 in/WC (1.01 PSI) or thereabouts. I know this issue
has
been loosely covered a few times before, but the question is:

What is the maximum recommended vacuum pressure, short of inviting an
implosion disaster? I need to calibrate the non-precision anxiety meter
to
max out at a slightly lower value.

Thanks.

Ron

PS - Along with your recommendation, please include your current home
address, driver's license, passport #, spouse's name, name and DOB of
first
born, etc.

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[Ron Shannon]

Thanks for another data point, Charlie. It'a a bit alarming to think you had
noticeable deformation of the tanks with only 18" WC (0.65 PSI) though. Got
the direct photo of your manometer. You should post it! :-)

I'd be leery of using a Shop Vac. Like the original attempt, for suction I
have a small Robinair Air-Vac, powered by an air hose with an inline
regulator just upstream of the Vac. The Air-Vac's output "T" connections go
to a precision 0-40 in/WC round gauge (new to the setup this time) and a
1/4" ID neoprene tube to one of my fuel cap snorkel vents. The opposite tank
snorkel is capped off with a short crimped tube. (Of course, I'm
depressurizing both tanks simultaneously because I can't easily close the
cross vent.) Under the snorkels, both tank caps still have the two tiny vent
holes in them for a little more relief leakage. With the inline air
regulator air hose, I can adjust the real vacuum seen at the output "T"
slowly and quite precisely.

At the moment, I'm cleaning off some Seal-All I've applied here and there in
the last several months, but will be taking another crack at this (hmm...
that's an unfortunate metaphor) later this AM.

Ron


On Wed, Mar 2, 2011 at 7:05 AM, Charlie Eubanks <charlie@troyairpark.com>wrote:

Hi Ron
I can't help you with the vacume it takes to damage your tank.I built a
Monometer out of 3/8 PVC clear tube mounted on a large piece of plywood
with
14.5 and 20" above and below 0". Stuck my shop vac hose in the tank and
sealed it with duck tape. I was able to pull about 18" and the tank walls
really sucked in. You can regulate it some what by how well you seal the
duck tape. If the tank gets to looking to bad pull the plug on the shop
vac.
Will send photo off line. Good luck. Let me know if successfull I may have
t
o do it again.
Charlie E. 802R

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[Bob Palmer]

For a few bucks you can get a vacuum style brake bleeder kit consisting
of a hand operated pump that has a pressure gauge, check valve, hoses
etc. The price varies quite a bit from automotive supply places.

Bob

On 3/2/2011 9:02 AM, Ron Shannon wrote:

Thanks for another data point, Charlie. It'a a bit alarming to think you had
noticeable deformation of the tanks with only 18" WC (0.65 PSI) though. Got
the direct photo of your manometer. You should post it! :-)

I'd be leery of using a Shop Vac. Like the original attempt, for suction I
have a small Robinair Air-Vac, powered by an air hose with an inline
regulator just upstream of the Vac. The Air-Vac's output "T" connections go
to a precision 0-40 in/WC round gauge (new to the setup this time) and a
1/4" ID neoprene tube to one of my fuel cap snorkel vents. The opposite tank
snorkel is capped off with a short crimped tube. (Of course, I'm
depressurizing both tanks simultaneously because I can't easily close the
cross vent.) Under the snorkels, both tank caps still have the two tiny vent
holes in them for a little more relief leakage. With the inline air
regulator air hose, I can adjust the real vacuum seen at the output "T"
slowly and quite precisely.

At the moment, I'm cleaning off some Seal-All I've applied here and there in
the last several months, but will be taking another crack at this (hmm...
that's an unfortunate metaphor) later this AM.

Ron


On Wed, Mar 2, 2011 at 7:05 AM, Charlie Eubanks<charlie@troyairpark.com>wrote:

Hi Ron
I can't help you with the vacume it takes to damage your tank.I built a
Monometer out of 3/8 PVC clear tube mounted on a large piece of plywood
with
14.5 and 20" above and below 0". Stuck my shop vac hose in the tank and
sealed it with duck tape. I was able to pull about 18" and the tank walls
really sucked in. You can regulate it some what by how well you seal the
duck tape. If the tank gets to looking to bad pull the plug on the shop
vac.
Will send photo off line. Good luck. Let me know if successfull I may have
t
o do it again.
Charlie E. 802R

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[Charlie Eubanks]

Ron
Sorry I didn't make that very clear. That was 18" above and below for a
total of 36".
Your way sounds better.
Charlie E.
----- Original Message -----
From: "Ron Shannon" <rshannon@cruzcom.com>
To: <rebel-builders@dcsol.com>
Sent: Wednesday, March 02, 2011 11:02 AM
Subject: Re: [rebel-builders] Re: max tank vacuum

Thanks for another data point, Charlie. It'a a bit alarming to think you
had
noticeable deformation of the tanks with only 18" WC (0.65 PSI) though.
Got
the direct photo of your manometer. You should post it! :-)

I'd be leery of using a Shop Vac. Like the original attempt, for suction I
have a small Robinair Air-Vac, powered by an air hose with an inline
regulator just upstream of the Vac. The Air-Vac's output "T" connections
go
to a precision 0-40 in/WC round gauge (new to the setup this time) and a
1/4" ID neoprene tube to one of my fuel cap snorkel vents. The opposite
tank
snorkel is capped off with a short crimped tube. (Of course, I'm
depressurizing both tanks simultaneously because I can't easily close the
cross vent.) Under the snorkels, both tank caps still have the two tiny
vent
holes in them for a little more relief leakage. With the inline air
regulator air hose, I can adjust the real vacuum seen at the output "T"
slowly and quite precisely.

At the moment, I'm cleaning off some Seal-All I've applied here and there
in
the last several months, but will be taking another crack at this (hmm...
that's an unfortunate metaphor) later this AM.

Ron


On Wed, Mar 2, 2011 at 7:05 AM, Charlie Eubanks
<charlie@troyairpark.com>wrote:

Hi Ron
I can't help you with the vacume it takes to damage your tank.I built a
Monometer out of 3/8 PVC clear tube mounted on a large piece of plywood
with
14.5 and 20" above and below 0". Stuck my shop vac hose in the tank and
sealed it with duck tape. I was able to pull about 18" and the tank walls
really sucked in. You can regulate it some what by how well you seal the
duck tape. If the tank gets to looking to bad pull the plug on the shop
vac.
Will send photo off line. Good luck. Let me know if successfull I may
have
t
o do it again.
Charlie E. 802R

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[Ron Shannon]

[Semi-random observations on this morning's process:]

I dunno, Charlie, but I just got this down to 16-17 in./W.C. and saw minor
but definite concave deflection of the bottom skins in all of the tank bays,
so stopped there. (Scary business.) In my particular setup, I did have to
seal one tank neck with duct tape (no cap) and also seal the tank
neck-to-cap area around the cap with the vac connection, in order to pull
down the vacuum. Because there is a fairly large volume of air between the
two tanks, and of course, continuing leakage here and there, it takes
several minutes for the vacuum to fully develop, so care should be taken to
keep an eye on it as it pulls down, and throughout the process, of course.

Even at "just" 16 in./W.C. (0.57 PSI) it takes quite a bit of air to
maintain the suction -- at least to the extent I have sealed the tanks. Your
mileage will vary on that, of course. My 5 HP 20 gal. compressor is cycling
quite a bit. I am running about 75 PSI at the compressor output, and 25 PSI
at the air regulator just upstream from the Air-Vac to hold vacuum. The
hangar is at 66 F.

I dabbed the Loctite 609 on with a nitrile-gloved finger along the seeping
seams and rivets, and did see some of the fluid being sucked in -- I think
-- though It's subtle. The 609 slowly eats the nitrile glove -- so used more
than one.

Before draining the tanks a couple weeks ago (pre-vacation travel) I had
marked the areas I wanted to cover. Daubing the 609 on with the finger onto
the bottom of the mounted wings is a little messy, leaving a drops & runs on
the surface, etc. I let it soak into the seams (I hope) for 5-10 min., then
wiped the surface lightly with a rag. Went to the other wing, then came back
and repeated this process on each area about three times. By the second
application on most places. and third on all, I couldn't discern any more
fluid being sucked in.

I was concerned that as I began to (hopefully) fill some of the offending
gaps, the reduction in leakage might cause vacuum pressure might build...
but that didn't seem to happen. It's not that precise I guess. However, I
did make frequent checks on the vacuum gauge while working.

The product data sheet at http://www.sjgogo.com/pdf/609-en.pdf indicated the
609 will reach 75% of final strength after about 30 min., so I'm holding the
vacuum for at least an hour since the last application.

I'll try to get a photo of the Air-Vac setup soon. The one I'm using is only
about $35. I had the tubing, and borrowed the gauge. Of course, the results
won't be know until I put fuel back into the tanks in a day or two. Will
report.

Ron


On Wed, Mar 2, 2011 at 11:05 AM, Charlie Eubanks <charlie@troyairpark.com>wrote:

Ron
Sorry I didn't make that very clear. That was 18" above and below for a
total of 36".
Your way sounds better.
Charlie E.
----- Original Message -----
From: "Ron Shannon" <rshannon@cruzcom.com>
To: <rebel-builders@dcsol.com>
Sent: Wednesday, March 02, 2011 11:02 AM
Subject: Re: [rebel-builders] Re: max tank vacuum

Thanks for another data point, Charlie. It'a a bit alarming to think you
had
noticeable deformation of the tanks with only 18" WC (0.65 PSI) though.
Got
the direct photo of your manometer. You should post it! :-)

I'd be leery of using a Shop Vac. Like the original attempt, for suction

I

have a small Robinair Air-Vac, powered by an air hose with an inline
regulator just upstream of the Vac. The Air-Vac's output "T" connections
go
to a precision 0-40 in/WC round gauge (new to the setup this time) and a
1/4" ID neoprene tube to one of my fuel cap snorkel vents. The opposite
tank
snorkel is capped off with a short crimped tube. (Of course, I'm
depressurizing both tanks simultaneously because I can't easily close the
cross vent.) Under the snorkels, both tank caps still have the two tiny
vent
holes in them for a little more relief leakage. With the inline air
regulator air hose, I can adjust the real vacuum seen at the output "T"
slowly and quite precisely.

At the moment, I'm cleaning off some Seal-All I've applied here and there
in
the last several months, but will be taking another crack at this (hmm...
that's an unfortunate metaphor) later this AM.

Ron


On Wed, Mar 2, 2011 at 7:05 AM, Charlie Eubanks
<charlie@troyairpark.com>wrote:

Hi Ron
I can't help you with the vacume it takes to damage your tank.I built a
Monometer out of 3/8 PVC clear tube mounted on a large piece of plywood
with
14.5 and 20" above and below 0". Stuck my shop vac hose in the tank and
sealed it with duck tape. I was able to pull about 18" and the tank

walls

really sucked in. You can regulate it some what by how well you seal the
duck tape. If the tank gets to looking to bad pull the plug on the shop
vac.
Will send photo off line. Good luck. Let me know if successfull I may
have
t
o do it again.
Charlie E. 802R

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[craig]

Ron,

How much of your tanks hve you exposed and where?
----- Original Message -----
From: "Ron Shannon" <rshannon@cruzcom.com>
To: <rebel-builders@dcsol.com>
Sent: Wednesday, March 02, 2011 11:38 AM
Subject: Re: [rebel-builders] Re: max tank vacuum

[Semi-random observations on this morning's process:]

I dunno, Charlie, but I just got this down to 16-17 in./W.C. and saw minor
but definite concave deflection of the bottom skins in all of the tank
bays,
so stopped there. (Scary business.) In my particular setup, I did have to
seal one tank neck with duct tape (no cap) and also seal the tank
neck-to-cap area around the cap with the vac connection, in order to pull
down the vacuum. Because there is a fairly large volume of air between the
two tanks, and of course, continuing leakage here and there, it takes
several minutes for the vacuum to fully develop, so care should be taken
to
keep an eye on it as it pulls down, and throughout the process, of course.

Even at "just" 16 in./W.C. (0.57 PSI) it takes quite a bit of air to
maintain the suction -- at least to the extent I have sealed the tanks.
Your
mileage will vary on that, of course. My 5 HP 20 gal. compressor is
cycling
quite a bit. I am running about 75 PSI at the compressor output, and 25
PSI
at the air regulator just upstream from the Air-Vac to hold vacuum. The
hangar is at 66 F.

I dabbed the Loctite 609 on with a nitrile-gloved finger along the seeping
seams and rivets, and did see some of the fluid being sucked in -- I think
-- though It's subtle. The 609 slowly eats the nitrile glove -- so used
more
than one.

Before draining the tanks a couple weeks ago (pre-vacation travel) I had
marked the areas I wanted to cover. Daubing the 609 on with the finger
onto
the bottom of the mounted wings is a little messy, leaving a drops & runs
on
the surface, etc. I let it soak into the seams (I hope) for 5-10 min.,
then
wiped the surface lightly with a rag. Went to the other wing, then came
back
and repeated this process on each area about three times. By the second
application on most places. and third on all, I couldn't discern any more
fluid being sucked in.

I was concerned that as I began to (hopefully) fill some of the offending
gaps, the reduction in leakage might cause vacuum pressure might build...
but that didn't seem to happen. It's not that precise I guess. However, I
did make frequent checks on the vacuum gauge while working.

The product data sheet at http://www.sjgogo.com/pdf/609-en.pdf indicated
the
609 will reach 75% of final strength after about 30 min., so I'm holding
the
vacuum for at least an hour since the last application.

I'll try to get a photo of the Air-Vac setup soon. The one I'm using is
only
about $35. I had the tubing, and borrowed the gauge. Of course, the
results
won't be know until I put fuel back into the tanks in a day or two. Will
report.

Ron


On Wed, Mar 2, 2011 at 11:05 AM, Charlie Eubanks
<charlie@troyairpark.com>wrote:

Ron
Sorry I didn't make that very clear. That was 18" above and below for a
total of 36".
Your way sounds better.
Charlie E.
----- Original Message -----
From: "Ron Shannon" <rshannon@cruzcom.com>
To: <rebel-builders@dcsol.com>
Sent: Wednesday, March 02, 2011 11:02 AM
Subject: Re: [rebel-builders] Re: max tank vacuum

Thanks for another data point, Charlie. It'a a bit alarming to think
you
had
noticeable deformation of the tanks with only 18" WC (0.65 PSI) though.
Got
the direct photo of your manometer. You should post it! :-)

I'd be leery of using a Shop Vac. Like the original attempt, for
suction

I

have a small Robinair Air-Vac, powered by an air hose with an inline
regulator just upstream of the Vac. The Air-Vac's output "T"
connections
go
to a precision 0-40 in/WC round gauge (new to the setup this time) and
a
1/4" ID neoprene tube to one of my fuel cap snorkel vents. The opposite
tank
snorkel is capped off with a short crimped tube. (Of course, I'm
depressurizing both tanks simultaneously because I can't easily close
the
cross vent.) Under the snorkels, both tank caps still have the two tiny
vent
holes in them for a little more relief leakage. With the inline air
regulator air hose, I can adjust the real vacuum seen at the output "T"
slowly and quite precisely.

At the moment, I'm cleaning off some Seal-All I've applied here and
there
in
the last several months, but will be taking another crack at this
(hmm...
that's an unfortunate metaphor) later this AM.

Ron


On Wed, Mar 2, 2011 at 7:05 AM, Charlie Eubanks
<charlie@troyairpark.com>wrote:

walls

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[Ron Shannon]

If I understand your question correctly, I haven't exposed any of the
insides of the tanks via access ports like you did -- yet.

My wings are mounted and flying, still unpainted. I have 5-8 rivets (heads
and/or mandrels) and the rear seams that seep on the bottom of each wing
tank. This thread is just about another attempt to suck Loctite 609 in from
the outside, because I'm still trying everything I can think of before
biting the bullet and cutting ports for an "inside out" re-seal job like you
eventually did. May get to that point, but I'm still holding out hope
something else will work.

Ron


On Wed, Mar 2, 2011 at 3:24 PM, craig <snowyrvr@mtaonline.net> wrote:

Ron,

How much of your tanks hve you exposed and where?

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[Ron Shannon]

Report on the Loctite sucking job:

Yesterday I made a second attempt at drawing in Loctite 609 to stop some
seepage in the bottom of the fuel tanks. I'm super happy to report that so
far, it appears to have done the job! I've had fuel back in the tanks for
4-5 hours and there's no sign of seeping fuel. (Before this latest effort,
some seepage would have shown up in multiple places in 15 min. or less.) Of
course, I won't know for sure if this will be a long term fix until the
wings have gone through some significant thermal cycles, and survived a few
of my standard landings <g> but at the moment I am cautiously optimistic,
and really glad that I may not have to cut six football-sized holes in the
bottoms of of the tanks for inside-out repairs after all. Yay!

There are a few factors that were different from my first attempt at this,
months ago, which probably made the difference. First, three weeks ago, I
went to great lengths to make sure the tanks had been completely drained --
even lifting the gear one side at a time for more complete drainage. Before
we went traveling, I left the fuel tank caps off, and covered the inlet with
netting to keep bugs out -- all of which allowed the tanks to dry out well
for almost three weeks. The second major difference, and probably the most
important, was use of a much better precision manometer to measure the
vacuum that was being developed in the tanks. Third was better sealing of
the fuel tank cap area -- which just meant less air flow was required to
build and maintain the necessary vacuum pressure. As noted earlier, I got to
16 in/WC (0.6 PSI) at which point the bottom skin panels of the tanks
started to show some slight concave deflection, so I stopped there.
Obviously I didn't know how much vacuum it might take to implode the tanks
(not much) but I certainly didn't want to find out. Bottom line is that 16
in/WC (66F) or about 0.5 PSI is enough! (There's a photo of the vacuum setup
at http://n254mr.com/node/1694 -- nothing special, but explanatory
nevertheless.)

When the original builder made the tanks many years ago, he tested them
carefully and held positive pressure in the tanks on a balloon for a couple
of days. Consequently, I don't know when or how the tanks developed some
seeping rivet heads and seams. The wings were twice moved almost 1000 miles,
and went through more than their share of handling over the years years, so
who knows? It's good to have them (apparently) fixed, because this little
nuisance has kept me from being all that eager about taking the plane
places, if for no other reason than it's embarrassing to have to explain the
gas smells to people on the ground, etc. :( Never more! I hope.

Onward.

Ron
N254MR




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[Walter Klatt]

Congratulations, Ron, that's fantastic. Your diligence and persistence has
paid off again. And you brought some new knowledge to the group which may
help someone else with the same problem. At worst, sounds like you may have
to do it again for a touch-up, but sure sounds like your method worked.

So now, when will we see that show plane paint job?

Walter

-----Original Message-----
From: mike.davis@dcsol.com [mailto:mike.davis@dcsol.com] On Behalf Of Ron
Shannon
Sent: Thursday, March 03, 2011 6:43 PM
To: rebel-builders@dcsol.com
Subject: Re: [rebel-builders] Re: max tank vacuum

Report on the Loctite sucking job:

Yesterday I made a second attempt at drawing in Loctite 609 to stop some
seepage in the bottom of the fuel tanks. I'm super happy to report that so
far, it appears to have done the job! I've had fuel back in the tanks for
4-5 hours and there's no sign of seeping fuel. (Before this latest effort,
some seepage would have shown up in multiple places in 15 min. or less.) Of
course, I won't know for sure if this will be a long term fix until the
wings have gone through some significant thermal cycles, and survived a few
of my standard landings <g> but at the moment I am cautiously optimistic,
and really glad that I may not have to cut six football-sized holes in the
bottoms of of the tanks for inside-out repairs after all. Yay!

There are a few factors that were different from my first attempt at this,
months ago, which probably made the difference. First, three weeks ago, I
went to great lengths to make sure the tanks had been completely drained --
even lifting the gear one side at a time for more complete drainage. Before
we went traveling, I left the fuel tank caps off, and covered the inlet with
netting to keep bugs out -- all of which allowed the tanks to dry out well
for almost three weeks. The second major difference, and probably the most
important, was use of a much better precision manometer to measure the
vacuum that was being developed in the tanks. Third was better sealing of
the fuel tank cap area -- which just meant less air flow was required to
build and maintain the necessary vacuum pressure. As noted earlier, I got to
16 in/WC (0.6 PSI) at which point the bottom skin panels of the tanks
started to show some slight concave deflection, so I stopped there.
Obviously I didn't know how much vacuum it might take to implode the tanks
(not much) but I certainly didn't want to find out. Bottom line is that 16
in/WC (66F) or about 0.5 PSI is enough! (There's a photo of the vacuum setup
at http://n254mr.com/node/1694 -- nothing special, but explanatory
nevertheless.)

When the original builder made the tanks many years ago, he tested them
carefully and held positive pressure in the tanks on a balloon for a couple
of days. Consequently, I don't know when or how the tanks developed some
seeping rivet heads and seams. The wings were twice moved almost 1000 miles,
and went through more than their share of handling over the years years, so
who knows? It's good to have them (apparently) fixed, because this little
nuisance has kept me from being all that eager about taking the plane
places, if for no other reason than it's embarrassing to have to explain the
gas smells to people on the ground, etc. :( Never more! I hope.

Onward.

Ron
N254MR




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[Ron Shannon]

Yes, well, not surprisingly, the headline motto on my web site ["Everything
is hard until you know how to do it"] certainly seems to apply to this task
like all the others. ;-)

The tank job is (was?) definitely one of the prerequisites to the paint job,
and could have been the biggest. I've got a few other things to do
(skylights, A/P roll servo, stab VG's, etc.) first, and I want to have the
plane still in flying mode when my daughter gets home for a few days later
this month. After that, paint may happen late April-ish or May. Especially
if I can find some slaves to do the prep!

Ron


On Thu, Mar 3, 2011 at 8:44 PM, Walter Klatt <Walter.Klatt@shaw.ca> wrote:

Congratulations, Ron, that's fantastic. Your diligence and persistence has
paid off again. And you brought some new knowledge to the group which may
help someone else with the same problem. At worst, sounds like you may have
to do it again for a touch-up, but sure sounds like your method worked.

So now, when will we see that show plane paint job?

Walter

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[Ron Shannon]

UPDATE on tank sealing with Loctite 609 and vacuum:

Two days ago I noticed there is still a very small seepage coming from 3-4
rivets. I had been checking daily, and it's taken several days for these to
appear, but they're definitely present. (The seams still show no signs of
leakage.) Although it's a bummer to find some leaks remaining, overall it's
at least 95% better than before, and I'm optimistic that another application
will probably get the rest. It may be awhile before I get to it though.
Draining and drying the tanks again will require some coordination with
other activities... like flying!

Ron
N254MR




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[snowyrvr]

seek and destroy, Ron!


--- rshannon@cruzcom.com wrote:

From: Ron Shannon <rshannon@cruzcom.com>
To: rebel-builders@dcsol.com
Subject: Re: [rebel-builders] Re: max tank vacuum
Date: Wed, 9 Mar 2011 10:39:19 -0800

UPDATE on tank sealing with Loctite 609 and vacuum:

Two days ago I noticed there is still a very small seepage coming from 3-4
rivets. I had been checking daily, and it's taken several days for these to
appear, but they're definitely present. (The seams still show no signs of
leakage.) Although it's a bummer to find some leaks remaining, overall it's
at least 95% better than before, and I'm optimistic that another application
will probably get the rest. It may be awhile before I get to it though.
Draining and drying the tanks again will require some coordination with
other activities... like flying!

Ron
N254MR




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