Applying New Seals

I am planning to place an order for control seals and tape to reseal
my glider (304CZ). For those of you who have recently done this to
your glider, what can you share to make this an easier job for me
to do?
Are there any special technics or tools required?
Any additional sealing information would be very much appreciated.

Randy

N304BU

On Oct 3, 6:33*pm, Randy wrote:
I am planning to place an order for control seals and tape to reseal
my glider (304CZ). For those of you who have recently done this to
your glider, what can you share to make this an easier job for me
to do?
Are there any special technics or tools required?
Any additional sealing information would be very much appreciated.

Randy

N304BU

I got the material from W&W. Clean off all the old seal residue.
Install in 90 degree heated hanger. Put a surface thermometer on the
wing to ensure the fiberglass is 90degrees. Now have someone run a
heat gun ahead of the second person applying the dbl sided tape
heating the fiberglass surface. Do the same for when applying the
mylar. It takes good heat for the chemicals in the dbl seal tape to
make a good bond. then apply the transfer tape. Works good last
long time.. I might have some pics if you want them.. S9

On Oct 3, 6:06*pm, Stephen wrote:
On Oct 3, 6:33*pm, Randy wrote:

I am planning to place an order for control seals and tape to reseal
my glider (304CZ). For those of you who have recently done this to
your glider, what can you share to make this an easier job for me
to do?
Are there any special technics or tools required?
Any additional sealing information would be very much appreciated.

Randy

N304BU

I got the material from W&W. Clean off all the old seal residue.
Install in 90 degree heated hanger. Put a surface thermometer on the
wing to ensure the fiberglass is 90degrees. Now have someone run a
heat gun ahead of the second person applying the dbl sided tape
heating the fiberglass surface. Do the same for when applying the
mylar. It takes good heat for the chemicals in the dbl seal tape to
make a good bond. *then apply the transfer tape. * *Works good last
long time.. * I might have some pics if you want them.. *S9

After 30 years in the repair business, I found the only way to insure
the mylar didn't lift was to sand both the inside of the mylar and the
corresponding wing (stab, fin) with 220 dry, then wipe both surfaces
with acetone just before applying double back sticky. Keep the DBS
straight as an arrow and then follow it in order to keep the Mylas
straight without any kinks. Sand only the 10mm area where the DBS will
go. If you get a kink, make a cut to remove it and press on.
I believe a good mylar job is all that in needed (internal seals not
necessary).
Cheers,
JJ

On Oct 4, 7:44*am, JJ Sinclair wrote:
On Oct 3, 6:06*pm, Stephen wrote:









On Oct 3, 6:33*pm, Randy wrote:

I am planning to place an order for control seals and tape to reseal
my glider (304CZ). For those of you who have recently done this to
your glider, what can you share to make this an easier job for me
to do?
Are there any special technics or tools required?
Any additional sealing information would be very much appreciated.

Randy

N304BU

I got the material from W&W. Clean off all the old seal residue.
Install in 90 degree heated hanger. Put a surface thermometer on the
wing to ensure the fiberglass is 90degrees. Now have someone run a
heat gun ahead of the second person applying the dbl sided tape
heating the fiberglass surface. Do the same for when applying the
mylar. It takes good heat for the chemicals in the dbl seal tape to
make a good bond. *then apply the transfer tape. * *Works good last
long time.. * I might have some pics if you want them.. *S9

After 30 years in the repair business, I found the only way to insure
the mylar didn't lift was to sand both the inside of the mylar and the
corresponding wing (stab, fin) with 220 dry, then wipe both surfaces
with acetone just before applying double back sticky. Keep the DBS
straight as an arrow and then follow it in order to keep the Mylas
straight without any kinks. Sand only the 10mm area where the DBS will
go. If you get a kink, make a cut to remove it and press on.
I believe a good mylar job is all that in needed (internal seals not
necessary).
Cheers,
JJ

JJ,

Do you agree with the requirement for heat?

WE

On Oct 4, 8:44*am, JJ Sinclair wrote:
On Oct 3, 6:06*pm, Stephen wrote:





On Oct 3, 6:33*pm, Randy wrote:

I am planning to place an order for control seals and tape to reseal
my glider (304CZ). For those of you who have recently done this to
your glider, what can you share to make this an easier job for me
to do?
Are there any special technics or tools required?
Any additional sealing information would be very much appreciated.

Randy

N304BU

I got the material from W&W. Clean off all the old seal residue.
Install in 90 degree heated hanger. Put a surface thermometer on the
wing to ensure the fiberglass is 90degrees. Now have someone run a
heat gun ahead of the second person applying the dbl sided tape
heating the fiberglass surface. Do the same for when applying the
mylar. It takes good heat for the chemicals in the dbl seal tape to
make a good bond. *then apply the transfer tape. * *Works good last
long time.. * I might have some pics if you want them.. *S9

After 30 years in the repair business, I found the only way to insure
the mylar didn't lift was to sand both the inside of the mylar and the
corresponding wing (stab, fin) with 220 dry, then wipe both surfaces
with acetone just before applying double back sticky. Keep the DBS
straight as an arrow and then follow it in order to keep the Mylas
straight without any kinks. Sand only the 10mm area where the DBS will
go. If you get a kink, make a cut to remove it and press on.
I believe a good mylar job is all that in needed (internal seals not
necessary).
Cheers,
JJ- Hide quoted text -

- Show quoted text -

I would add emphasis that ALL previous residue has got to be off which
may require more than 220. Then finish with
220.
It is also very helpful to deflect the surface away from the seal
while curing. If you do both sides at once and come back the next day
to popped seal, the natural tendancy is to rub it back down. Likely
this will go on until you rip the whole thing off and do it again.
Wanna know how I know? Nah
UH

JJ,

Do you agree with the requirement for heat?

WE- Hide quoted text -

- Show quoted text -

I haven't tried heat, it may work. The proof is in how long it stays
down. The stuff isn't cheap and quite a bit of work to replace. I have
used a heat gun to help remove the old DBS. Heat it up till you can
roll up the goo with your thumb. No problems since I started sanding
both surfaces. The mylar on my Genesis is about 9 years old now and
none of it has lifted. I even used 2 or 3 layers in places to build up
a low spot after replacing the left aileron with an early unit that
was a tad thicker.
Cheers,
JJ

Tips for removing seals:

1) use a hair dryer or heat gun to warm things up. At 100 F plus, the
seal can usually be peeled back (slowly) span wise and take virtually
all of the adhesive residue with it. Work the heat gun on the area
just ahead of the peel point. Go slow, don't overheat. Your should
just be able to hold a finger or thumb on the heated surface. 110 -
120F. Most people can't keep a hand on 120F or more.

2) clean remaining residue with 3M red can adhesive remover. Good
chemical resistant gloves recommended.

Tips for application:

1) Clean gelcoat with 3m adhesive remover thoroughly.

2) Apply bonding tape, DO NOT STRETCH. It must be straight.
Everything must go down stress free. Rub down with metal spoon.
Leave cover (non-adhesive) film in place for now.

3) Position Mylar where you want it. It must be absolutely stress
free & straight. Hold in place with strips of electrical tape (gap
seal tape) about 4 inches long every foot. The gap seal tape goes on
span wise, more or less as you would anti-peel tape. The leading edge
of the mylar must be exactly in line with the leading edge of the
bonding tape.

4) Fold back the mylar on the hinge created by the gap seal tape,
tape it with more gap seal tape to hold it folded back and clean
underside of mylar with adhesive remover. Let dry (30 seconds).

5) Remove protective film from bonding tape.

6) Now work carefully from one end, "roll" the mylar into place on the
gap seal tape hinge. The objective is to bring the entire bonding
surface into very light, continuous contact. After the whole seal is
lightly in contact, rub down with spoon.

7) Clean top side of mylar and just ahead on wing with adhesive
remover. Apply safety tape. Do not stretch.

If you do that as I've described, you don't need to sand anything.
That said, sanding probably doesn't hurt.

This all goes best on a minimum 70 degree day. I agree that some heat
helps establish the bond. If in doubt, warm things up with a hair
dryer and rub down again. Final tip: don't try to do this under time
pressure (i.e. on flying day). Do it fast and sloppy... do it again
real soon. Do 'em correctly, they last for years and years. Make
certain that trailer fixtures maintain control surfaces in neutral
position.

I have had problems with adhering to routed out composite surfaces
(e.g. ASW-24 ailerons). I suspect one way to deal with this is paint
the surface with a very thin coat of epoxy and allow to cure fully
before applying sealing materials. Have not had to try that yet.
Better ideas?

-Evan Ludeman / T8

On Oct 4, 11:04*am, T8 wrote:
Tips for removing seals:

1) use a hair dryer or heat gun to warm things up. *At 100 F plus, the
seal can usually be peeled back (slowly) span wise and take virtually
all of the adhesive residue with it. *Work the heat gun on the area
just ahead of the peel point. *Go slow, don't overheat. *Your should
just be able to hold a finger or thumb on the heated surface. *110 -
120F. *Most people can't keep a hand on 120F or more.

2) clean remaining residue with 3M red can adhesive remover. *Good
chemical resistant gloves recommended.

Tips for application:

1) Clean gelcoat with 3m adhesive remover thoroughly.

2) Apply bonding tape, DO NOT STRETCH. *It must be straight.
Everything must go down stress free. *Rub down with metal spoon.
Leave cover (non-adhesive) film in place for now.

3) Position Mylar where you want it. *It must be absolutely stress
free & straight. *Hold in place with strips of electrical tape (gap
seal tape) about 4 inches long every foot. *The gap seal tape goes on
span wise, more or less as you would anti-peel tape. *The leading edge
of the mylar must be exactly in line with the leading edge of the
bonding tape.

4) *Fold back the mylar on the hinge created by the gap seal tape,
tape it with more gap seal tape to hold it folded back and clean
underside of mylar with adhesive remover. *Let dry (30 seconds).

5) Remove protective film from bonding tape.

6) Now work carefully from one end, "roll" the mylar into place on the
gap seal tape hinge. *The objective is to bring the entire bonding
surface into very light, continuous contact. *After the whole seal is
lightly in contact, rub down with spoon.

7) *Clean top side of mylar and just ahead on wing with adhesive
remover. *Apply safety tape. *Do not stretch.

If you do that as I've described, you don't need to sand anything.
That said, sanding probably doesn't hurt.

This all goes best on a minimum 70 degree day. *I agree that some heat
helps establish the bond. *If in doubt, warm things up with a hair
dryer and rub down again. *Final tip: don't try to do this under time
pressure (i.e. on *flying day). *Do it fast and sloppy... do it again
real soon. *Do 'em correctly, they last for years and years. *Make
certain that trailer fixtures maintain control surfaces in neutral
position.

I have had problems with adhering to routed out composite surfaces
(e.g. ASW-24 ailerons). *I suspect one way to deal with this is paint
the surface with a very thin coat of epoxy and allow to cure fully
before applying sealing materials. *Have not had to try that yet.
Better ideas?

-Evan Ludeman / T8

Thin CA glue seems to work as a surfacer that helps when bonding to
routed surfaces. Tape seems to like the smoother surface.
Epoxy works well but CA is instant.
I still sand and scrape carefully.
FWIW
UH

What if the top white glossy 'safety tape' has started to peel but the
mylar gap seal is still attach firmly with no issues. Is this an
indication that the mylar is in need of replacement or simply clean
the mylar surface and re-apply the safety tape?
Thanks,
R

There have been accidents when the Mylar was not installed properly,
came loose, which disrupted the airflow over the control surface,
causing a major change in controllabilty.

If you don't REALLY know what you are doing, it is better to have it
done by a professional. This is a serious task.

Tom