fiberglass tapes

[Lou]

Ok, I want to reinforce all my corners with fiberglass tape. Aircraft
Spruce sells a 50 yard 8.7 oz tape to do this job. Can anyone tell me
why I shouldn't use cut strips of my 1.4 oz cloth instead of this very
heavy tape?
Lou

[Bob Kuykendall]

Earlier, Lou wrote:
> Ok, I want to reinforce all my corners with fiberglass tape. Aircraft
> Spruce sells a 50 yard 8.7 oz tape to do this job. Can anyone tell me
> why I shouldn't use cut strips of my 1.4 oz cloth instead of this very
> heavy tape?

For one, I don't think of 9 oz tape as being particularly "heavy" for
corner reinforcement. I find it's a relatively convenient weight; two
to five plies (depending on application) of it are about right for most
taped-in bulkheads and such. I don't know what you're building, but 1.4
ounce is lighter than anything I use except for veil cloth.

The thing about the prefab tapes is that the edges are hemmed (or
whatever you call it) so they aren't always unraveling at the edges.
That's a huge advantage when you're putting down a lot of the stuff.

Here's another thing to consider, though: If you cut your own tapes you
can cut them on the bias for easier draping and better shear strength.
Such tapes also don't unravel as much at the edges, since there are no
fibers parallel with the cut edge. The disadvantages to bias tapes are
that they are hard to keep of consistent width (they keep doing the
"Chinese handcuffs" thing), and that you can't have lengths greater
than about 1.4 times the width of the roll.

I guess the best thing to do is whatever it says in the plans you're
working from.

Thanks, Bob K.
http://www.hpaircraft.com

[Cy Galley]

One really big advantage to a bias tape is its ability to conform to
complex shapes. It will also stay in the corner better and all the fibers
are NOT crossing a right angles.

Old Vari-Eze builder.


"Lou" > wrote in message
ps.com...
> Ok, I want to reinforce all my corners with fiberglass tape. Aircraft
> Spruce sells a 50 yard 8.7 oz tape to do this job. Can anyone tell me
> why I shouldn't use cut strips of my 1.4 oz cloth instead of this very
> heavy tape?
> Lou
>

[Reggie]

One way to keep your hand cut,45 deg, bias tapes neat and uniform
is to lay them up on clear poly (Home Depot plastic sheeting) then
after you get them worked to your best epoxy / glass ratio,
cut the assembly to your needed width & length and cary the layup
with the nonstretching poly backing , flip over and apply to the
joint.

Peal the backing off , finish and inspect.

Reggie

[ED]

Reggie wrote:
> One way to keep your hand cut,45 deg, bias tapes neat and uniform
> is to lay them up on clear poly (Home Depot plastic sheeting) then
> after you get them worked to your best epoxy / glass ratio,
> cut the assembly to your needed width & length and cary the layup
> with the nonstretching poly backing , flip over and apply to the
> joint.
>
> Peal the backing off , finish and inspect.
>
> Reggie


While the tape may be more convenient, the extra thickness of the edge
sticks out. What I like to do is roll out a piece of plastic wrap,
roll a piece of peel ply on top, paint on a little resin, roll out the
bias tape, saturate with resin, roll out the narrower hemmed tape,
apply a light coat of resin in the corners, apply the whole works. You
can run your fingers against the plastic to insure good contact. Then
get a piece of foam rubber with a wood backing, press against the
plastic with weights, clamps, etc. to keep pressure on. The peel ply
will absorb excess resin and when cured and peeled off, the joint will
look great. Spray on some light grey primer and finish with spatter
paint.

Ed

[Roger (K8RI)]

On 20 Oct 2006 13:03:09 -0700, "Reggie" > wrote:

> One way to keep your hand cut,45 deg, bias tapes neat and uniform
> is to lay them up on clear poly (Home Depot plastic sheeting) then
>after you get them worked to your best epoxy / glass ratio,
>cut the assembly to your needed width & length and cary the layup
>with the nonstretching poly backing , flip over and apply to the
>joint.
>
>Peal the backing off , finish and inspect.

That's one of the methods they show for doing multiple lay-ups such as
the wing attach points on the G-III. I've wasted more fiberglass and
resin trying to do that than on any other approach<sigh> It sounds
good in theory and I've seen guys do it successfully, but not me.

It depends on the surface, but if I can lay the tape on top: I use a
cloth marking pen (marks disappear in an hour or so) to mark the cloth
on the cutting table, roll the tap up, mark the surface on which the
lay-up will be done for the proper width, wet the surface with a
light coat of resin, lay the tape out as I unroll it (push to widen,
or pull the narrow - do the same while stippling) then using a one
inch paint brush, stipple the resin into the tape.

I use vinyl ester resin which has a much lower viscosity than most
epoxies although the West System is fairly low.

>
>Reggie
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com

[Reggie]

>
> > One way to keep your hand cut,45 deg, bias tapes neat and uniform
> > is to lay them up on clear poly (Home Depot plastic sheeting) SNIP
> >Peel the backing off , finish and inspect.
>> >Reggie
>************************************************** *****************************
>"ED" >
>While the tape may be more convenient, the extra thickness of the edge
>sticks out. What I like to do is roll out a piece of plastic wrap,
>roll a piece of peel ply on top, paint on a little resin, roll out the
>bias tape, saturate with resin, roll out the narrower hemmed tape,
>apply a light coat of resin in the corners, apply the whole works.Snip
>
>Ed
>************************************************** **************
>Roger (K8RI) wrote:
>SNIP<
> It depends on the surface, but if I can lay the tape on top: I use a
> cloth marking pen (marks disappear in an hour or so) to mark the cloth
> on the cutting table, roll the tap up, mark the surface on which the
> lay-up will be done for the proper width, wet the surface with a
> light coat of resin, lay the tape out as I unroll it (push to widen,
> or pull the narrow - do the same while stippling) then using a one
> inch paint brush, stipple the resin into the tape.
>
> Roger Halstead (K8RI & ARRL life member)
>************************************************** ***************************
While each of these systems works,most stippled corner tapes that I
have seen come in heavier than they need to be. Ed's method of
placing a slightly narrower tape under the final tape gives a thinner
edge, and is what I do, but the peel ply can hide inspection and
makes the joint smother but also heavier. Most scratch built composite

airframes that do not pay close attention to these small weight
increases
ending up weighing more than necessary.
That straight tape edge adds points at Oshkosh and less weight allows
one to climb faster. Reggie
************* ALSO *******************

> "Lou" wrote:
>
>Ok, I want to reinforce all my corners with fiberglass tape. Aircraft
>Spruce sells a 50 yard 8.7 oz tape to do this job. Can anyone tell me
>why I shouldn't use cut strips of my 1.4 oz cloth instead of this very
>heavy tape?
> Lou
>************************************************** ****
If you use enough plys so that the strength exceeds the peel strength
of the joint and is as strong as the skins you are joining ,go for it.
It may take a few layers and will use more epoxy.
Reggie

[Roger (K8RI)]

On 21 Oct 2006 17:22:07 -0700, "Reggie" > wrote:

>>
>> > One way to keep your hand cut,45 deg, bias tapes neat and uniform
>> > is to lay them up on clear poly (Home Depot plastic sheeting) SNIP
>> >Peel the backing off , finish and inspect.
>>> >Reggie
>>************************************************** *****************************
>>"ED" >
>>While the tape may be more convenient, the extra thickness of the edge
>>sticks out. What I like to do is roll out a piece of plastic wrap,
>>roll a piece of peel ply on top, paint on a little resin, roll out the
>>bias tape, saturate with resin, roll out the narrower hemmed tape,
>>apply a light coat of resin in the corners, apply the whole works.Snip
>>
>>Ed
>>************************************************** **************
>>Roger (K8RI) wrote:
>>SNIP<
>> It depends on the surface, but if I can lay the tape on top: I use a
>> cloth marking pen (marks disappear in an hour or so) to mark the cloth
>> on the cutting table, roll the tap up, mark the surface on which the
>> lay-up will be done for the proper width, wet the surface with a
>> light coat of resin, lay the tape out as I unroll it (push to widen,
>> or pull the narrow - do the same while stippling) then using a one
>> inch paint brush, stipple the resin into the tape.
>>
>> Roger Halstead (K8RI & ARRL life member)
>>************************************************** ***************************
>While each of these systems works,most stippled corner tapes that I
>have seen come in heavier than they need to be. Ed's method of

On the G-III with the Vinyl Ester resin the cloth is quite a bit more
dense than that used with epoxy. I just cut the corner reinforcement
out of regular cloth on the 45 bias. Glasair used to use a bias tape,
but they have eliminated that and have gone to using the regular cloth
cut on the 45. With a reference mark you can get a pretty straight
edge.

>placing a slightly narrower tape under the final tape gives a thinner
>edge, and is what I do, but the peel ply can hide inspection and

Squeezing out the peel ply (I use Dacron it's cheaper and works just
as well) will give tapered edges and tends to spread the fibers at the
edge of the cloth as well.

>makes the joint smother but also heavier. Most scratch built composite

Done correctly the peel ply should remove the excess resin giving a
lay up without excess resin or weight. At least the stuff I'm using
sure does wick off the excess. The biggest problem is learning how
much "excess" resin to put on depending on the weave of the peel ply
during the lay-up so the peel ply doesn't make it too dry.
A normal lay-up with the coarse weave will come out almost white which
is too dry.

We have one guy building a Glasair Super II whose plain lay-ups look
better than mine using peel ply. He is good!

>
>airframes that do not pay close attention to these small weight
>increases
>ending up weighing more than necessary.
> That straight tape edge adds points at Oshkosh and less weight allows

I don't have any tape edges that show. For peel ply I have four
different Dacron weaves that give me finishes from smooth to those
that look almost dry depending on what comes next.


>one to climb faster. Reggie
> ************* ALSO *******************
>
>> "Lou" wrote:
>>
>>Ok, I want to reinforce all my corners with fiberglass tape. Aircraft
>>Spruce sells a 50 yard 8.7 oz tape to do this job. Can anyone tell me
>>why I shouldn't use cut strips of my 1.4 oz cloth instead of this very
>>heavy tape?
>> Lou
>>************************************************** ****
> If you use enough plys so that the strength exceeds the peel strength
>of the joint and is as strong as the skins you are joining ,go for it.
> It may take a few layers and will use more epoxy.
>Reggie
Roger Halstead (K8RI & ARRL life member)
(N833R, S# CD-2 Worlds oldest Debonair)
www.rogerhalstead.com