Laminating an aileron spar

I need to add about 1/4" strip to the edge of my newly purchased
spruce aileron spar, 'cause I need to add a bevel. The spar is 3" wide
so the proposed strip is only a fraction of the area.

Can anyone see a problem if I used fir instead of spruce for this
strip? Fir is more easily available locally - Mike

Michael Horowitz wrote:

I need to add about 1/4" strip to the edge of my newly purchased
spruce aileron spar, 'cause I need to add a bevel. The spar is 3" wide
so the proposed strip is only a fraction of the area.

Can anyone see a problem if I used fir instead of spruce for this
strip? Fir is more easily available locally - Mike

Mike?

You need to add a 1/4" strip - that is going to be mostly beveled off?

This is a trick question, right?

What would it matter what you used for this??


Richard

cavelamb himself wrote:
Michael Horowitz wrote:

I need to add about 1/4" strip to the edge of my newly purchased
spruce aileron spar, 'cause I need to add a bevel. The spar is 3" wide
so the proposed strip is only a fraction of the area.

Can anyone see a problem if I used fir instead of spruce for this
strip? Fir is more easily available locally - Mike

Mike?

You need to add a 1/4" strip - that is going to be mostly beveled off?

This is a trick question, right?

What would it matter what you used for this??


Richard


I'd glue it on real good--don't depend on tacks or staples--jerry

"Jerry Wass" wrote

I'd glue it on real good--don't depend on tacks or staples--jerry

Yeah, you wouldn't want it to be "tacky." g
--
Jim in NC

On Tue, 27 Mar 2007 03:29:49 GMT, cavelamb himself
wrote:

Michael Horowitz wrote:

I need to add about 1/4" strip to the edge of my newly purchased
spruce aileron spar, 'cause I need to add a bevel. The spar is 3" wide
so the proposed strip is only a fraction of the area.

Can anyone see a problem if I used fir instead of spruce for this
strip? Fir is more easily available locally - Mike

Mike?

You need to add a 1/4" strip - that is going to be mostly beveled off?

This is a trick question, right?

What would it matter what you used for this??


Richard


Richard - thanks for the reply. I am concerned about two things;
because pine (for example) has a different density than spruce, they
might react differently to humidity or temp change and affect the
straightness of the spar. Second; some A&P looking at it and reject
the repair.

Granted, the amount is so small, I'm probably worried about nothing,
but being part of the USG, I"ve seen minor things become bent way out
of shape just because someone got their teeth into it. - Mike

Do you think I'm being unreasonable?

Michael Horowitz wrote:
On Tue, 27 Mar 2007 03:29:49 GMT, cavelamb himself
wrote:


Michael Horowitz wrote:


I need to add about 1/4" strip to the edge of my newly purchased
spruce aileron spar, 'cause I need to add a bevel. The spar is 3" wide
so the proposed strip is only a fraction of the area.

Can anyone see a problem if I used fir instead of spruce for this
strip? Fir is more easily available locally - Mike

Mike?

You need to add a 1/4" strip - that is going to be mostly beveled off?

This is a trick question, right?

What would it matter what you used for this??


Richard



Richard - thanks for the reply. I am concerned about two things;
because pine (for example) has a different density than spruce, they
might react differently to humidity or temp change and affect the
straightness of the spar. Second; some A&P looking at it and reject
the repair.

Granted, the amount is so small, I'm probably worried about nothing,
but being part of the USG, I"ve seen minor things become bent way out
of shape just because someone got their teeth into it. - Mike

Do you think I'm being unreasonable?

Probably, but that's ok.

Like Jerry said, glue it on. (With a good epoxy - I'd use T-88)
The strip is so small it shouldn't cause any problems.

Richard

"I am concerned about two things; because pine (for example) has a different
density than spruce, they might react differently to humidity or temp change
and affect the straightness of the spar."

I do not think the difference in density will be the problem. A thin piece
of dried wood, when attached to a larger piece of wood will continue to
adapt to the shape of the larger piece of wood. The larger spruce would not
be any more likely to warp - but for the fact that one side is now protected
from the moisture - and that would occur no matter what kind of wood you
use.

The completed piece should be no more likely to warp than the original
piece.

As to the second part of the concern - about the inspection - ask the
inspector in advance. Remember, it is experimental.

Colin

COLIN LAMB wrote:
"I am concerned about two things; because pine (for example) has a different
density than spruce, they might react differently to humidity or temp change
and affect the straightness of the spar."

I do not think the difference in density will be the problem. A thin piece
of dried wood, when attached to a larger piece of wood will continue to
adapt to the shape of the larger piece of wood. The larger spruce would not
be any more likely to warp - but for the fact that one side is now protected
from the moisture - and that would occur no matter what kind of wood you
use.

The completed piece should be no more likely to warp than the original
piece.

As to the second part of the concern - about the inspection - ask the
inspector in advance. Remember, it is experimental.

Colin

COLIN LAMB wrote:
Remember, it is experimental.

Colin

Nope: certified

On 27 Mar 2007 07:36:25 -0700, "mhorowit" wrote:


COLIN LAMB wrote:
Remember, it is experimental.

Colin

Nope: certified


My A&P wants spruce or fir, so fir it will be
Thanks to all - MIke