Frank- trying to make an 80 year-old retired pilot smile- a 50" span Tiger Moth

[Frank v B]

Next step: Attaching the bottom wing.

Note- since the fuse, fin and stab came already glued in place, I am using these as starting points.
Object: make the wing true to the stab... even if it is crooked on the fuselage.

Step 1- find the centre of the wing.  Not so easy since the wing sheeting was not in the centre and the wing has a sweep-back and dihedral.  Found the centre of the trailing edge by holding a tape measure across the back end of the wing tips.  Marked the centre with a magic marker.  Found the centre of the leading edge by placing the wing over our ceramic laundry room floor.  The wing tip leading edge was 3" behind one grout line and the wing tips overlapped another grout line by equal amounts.  Stood above it and when the trailing edge magic marker dot was in line with a grout line, I make the front on the same grout line.  Close enough.
See photo 78.

Step 2- Make a leading edge dowel. Cut it to length and sharpen the point a little with a pencil sharpener so it becomes self centring. See photo 80.  Note: once the first one was drilled and centred, I drilled the second one.  I always use two leading edge dowels and two trailing edge bolts on my wings.  safety.

Step 3 Drill one leading edge dowel hole in the leading edge and fuse.  Oops- drilled into the Landing gear wire.  Will leave it and re-inforce it later.  Mark and install the trailing edge screw hold-down plate.  I used 3/4" square hard balsa.  Once the glue dries, I will drill and tap it into the balsa for two nylon bolts.  Photo 81.  Notice how butchered the holes for the dowels were in the fuselage.  You can see the landing gear metal in the holes.

Frank

[davidk]

A ceramic floor and a pencil sharpener.  You really do use all the tools around the house. 

This is looking really good.

[Frank v B]

Gotta keep going!

Photo 88- tapped the holes for the lower wing bolts
Photo 91- put the nylon wing bolts through the pencil sharpener so they automatically centre in the hole.  The left bolt is untouched, the right one has been sharpened with the shavings next to it.
Photo 89- next challenge.  The cabane struts, as built, are very crooked.  The tail wheel and prop nut are centered on the grout line in the photo.  Appears to be off by about 3 degrees.  Will have to compensate for it.
Photo 92- everything looks crooked.  That is why we have trim tabs on transmitters.
Photo 94- Top view of the plane with the bottom wing in place.

To get away from the crookedness of the cabanes, my approach will be to rest the top wing properly aligned on the interplane wing struts and then fasten the top wing onto the cabane struts in the centre....... It will be crookedly straight.

Frank

[piker]

Excellent perseverance Frank!  Keep at it!

Hey!  Can the cabane struts be cracked and re-glued somehow to straighten them up?

Robert

[Frank v B]

Rob,

Thanks for the comment.  It appears to be a compliment. 

I am walking a fine line between making sure this plane can fly its one flight while maintaining as much of the owner's original construction so he can see his plane, not mine, fly.  All my adjustments are strength and alignment related so it can fly.  A little crooked stuff here and there won't hurt it.  All the planes I have ever built proves this is true. 
We won't be competing with it at the National Championships.... and my name is not Piker!  (Mr. Accurate! and Precise)

One thing is for sure. Starting new with a kit would have been a lot faster... but this is neither the assignment nor the objective.

Frank

[Frank v B]

Wing incidence for a biplane.

Did a bit of research on the incidence of the wings.

It seems like you want the bottom wing, especially the more forward wing to stall first.
Details on the following web question on RCGroups.https://www.rcgroups.com/forums/showthread.php?2576270-Biplane-Wing-Incidence-Recommendation

Decision... unless the TEMAC experts indicate this is stupid... I will put about 2 degrees of decalage (difference in the angle of attack between the upper and lower wing) on the wing with the lower wing at 0 degrees to the stab.

Frank

[davidk]

This sounds correct to me.   

To put at it another way, I feel the decalage should be set at just enough. 

Very hard to believe you're actually using numbers.  I knew there'd come a day!

[piker]

Sounds good to me.

I recall my SE5a requiring between 1 and 2 degrees positive relative to the bottom wing. 

[Frank v B]

David,

re: your "Very hard to believe you're actually using numbers.  I knew there'd come a day!"

All I can say is "19, 15, 18, 18, 25".

If you want me to be more accurate about the incidence, then call it "just enough plus .1".   

Frank

[msatin]

I have so much to learn.
I thought decalage referred to the methodology used to "apply decals" 
Really coming along nicely Frank

[Frank v B]

a few details done last night-

Photo 98- filled in the lower wing leading edge
Photo 99- glued thin plywood protection (1/64") on the bottom of the wing so the wing bolts do not bite into the balsa sheeting.
Photo 600- added 1/16 ply on the bottom of the nose between the landing gear.  The balsa underneath was about 10 pieces glued together.  The plywood adds a smooth surface without adding thickness so the cowl still fits.

Frank

[Frank v B]

Fibreglassing the bottom of the bottom wing.

- Applied 5 minute epoxy to the balsa airframe
- laid fibreglass cloth over the glue
- covered it with two pieces of waxed paper so it can handle the dihedral joint
- spread the glue by rubbing the waxed paper and forcing the glue through the cloth.
- let cure overnight (as opposed to just "harden").

Will do the top of the wing tomorrow and then bring it to the Build Class.

Frank

[RogMason]

Great project Frank.

Thanks for the very interesting talk and show n' tell at this evening's Pilot Meeting. The Tiger Moth was such a worthy aeroplane, purposely designed to bring flying to the masses. I'm certain the model will stand a chance to look proud and to fly, under your expert eye. It is such a worthy cause.

I'd be interested to learn whether the 80 yr old TCA pilot you called Ray, is in fact Captain Ray Lank?

[RogMason]

Frank, 
Here's a bio on Ray Lank, retired TCA pilot who flew the 'Sentimental Journey' across Canada.

http://www.oursussexroots.com/julia2a/39.htm

[Frank v B]

Found a nice photo of a Tiger Moth in Canadian Livery.  Canadian Warplane Heritage.  This one is stationed in Gatineau.
Unless Roger That comes up with a better specific Tiger Moth I will work towards this one.

Frank


ps: Roger.  I hope you can come up with a photo of a Canadian historic Tiger Moth.  I needed this one in order to find the location and angle of the wing struts and the correct stagger of the wing.