Looking for a DER/Structural

[mhorowit]

I have a question for a DER who specializes in aircraft structural.
It's a welding question.
Anyone on line? - Mike

[mohawk]

Hi,

Have some aviation experience, 20 years AME with structures. What is
your question? If I don't know I bet I Know someone who does.

Mark

mhorowit wrote:
> I have a question for a DER who specializes in aircraft structural.
> It's a welding question.
> Anyone on line? - Mike

[mhorowit]

mohawk wrote:
> Hi,
>
> Have some aviation experience, 20 years AME with structures. What is
> your question? If I don't know I bet I Know someone who does.
>
> Mark
>
> mhorowit wrote:
> > I have a question for a DER who specializes in aircraft structural.
> > It's a welding question.
> > Anyone on line? - Mike

Great - thanks for the offer. I"m looking at Figure 4-36 in 43-13-1B
"Welded patch repair".
I'm wondering if it would be acceptable to modify the patch so that
instead of that approx. 30 degree downward slope, the edge went 90
degrees down so that the patch wrapped around like it does for a
extenal splice on a strut. In this case it would wrap around 270
degrees. I'm thinking the length of the welds would be about the same.
Wondering what engineering concerns would make this unacceptable. This
is for the leading edge of my rudder, which has a rust hole in the 4130
steel. The reason I'm looking at a deviation from figure 4-36 is that
if I follow the illustration, the edge will just cover a bolt hole, and
if I redrill the hole, I'll be drilling thru a weld, thereby weakening
it. - Mike



Reason

[Scott Derrick]

I'm repainting a fiberglass airplane.

Sanding the wings, once removed from the plane is a fairly easy chore,
however sanding the underside of the fuselage and strakes is going to be
a major chore.

A body shop near the airport has a soda blaster that they will let me
use. I've heard of folks using these to remove old paint from boats and
planes.

Is it possible to use a soda blaster to remove only the top coat and not
remove the primer and micro beneath??? Basically use it to do the 60
grit sanding job and then follow with the relatively easier 150 and 240
grit sanding to prepare for primer?

Anybody do this and actually save time and effort?

Scott