Dave Smith/Tom Martin 1/4 Scale Hall Cherokee Build

[ingrahal]

Update continued:

Gluing the bottom spar cap to the sheeting. I used a straight edge to lay out the spar cap so the ribs will be nice and straight.


If you get it right you get this.



I used scraps of Divinycell foam to fill in above and below the wing rod sleeve.


Update continued on next post.

[ingrahal]

Update continued:

Shear webs are all glued in.



The top spar cap being glued on. I know you guys like the shell boxes so here you go.


Continuing with right wing panel.


That's it for now. Back to the shop.

[lar73]

Art, no wonder I like your builds so much. They are a work of art. That wing is straight as an arrow. I can't wait to see this plane completed and flying at Huntsville.

[ingrahal]

Thank you I'm glad you're enjoying the build.

[ingrahal]

Larry, nice avatar picture! Don't you have one of the model?

[stihac]

Way to go Art! Enjoying your updates.

Petr

[ingrahal]

Thanks Petr !!!

[JimD]

Glad you are back to building Art...every day without progress pictures was sad. We all really look forward to your daily dose of building magic!

[ingrahal]

Thanks Jim!!! Maybe someday I'll make it to Super Moderator status!

[ingrahal]

Update time:

I have made more progress on the wings. I'm building both panels at once to save time. So far it's working quite well, there are natural stopping points that make it efficient to bounce back and forth between right and left. You also avoid the dread of repeating it all over again after you finish one wing.

Due to the under-camber I found it necessary to use small wedges to raise the bottom sheeting and spar cap to the ribs for gluing.


The right wing ribs and shear webs are in.


I wanted to bevel the bottom of the sub-leading edge prior to gluing it in and rather than sanding it I found a Dremel bit with just the right angle of cut.


With it and the router table accessary I made short work of prepping the 1/8" X 3/4" sub-leading edge.


Update continued on next post....

[ingrahal]

Update continued:

Next I glued the bottom sheeting to the ribs by using thin CA and prying up on the sheeting.


Then I glued the sub-leading edge to the ribs and sheeting with thin CA.


Here the spar cap on the right wing has been epoxied and cured over night. I'm sanding it flush with the ribs.


After planing and sanding the sub-leading edge we're ready for the top sheeting.


Continued on next post....

[Dave Smith]

Great stuff, Art! Just the way it should be done!

DS

[ingrahal]

Thanks Dave! I missed your comment until just now. You must have slipped it in as I was posting.

[ingrahal]

Update continued:

Gluing down the top sheeting with extra thick CA.


More planing and sanding.


Both panels are ready for the leading and trailing edges.



That's it for now.

[Dion Dunn]

How in the world did you do the top sheeting with thick CA? I would have a crooked mess in about 3.2 seconds. Lately I've been using the wood glue/hot iron technique with great results.

[ingrahal]

Hey Dion, the "extra thick" CA allows more open time and some repositioning. The most important step when applying the sheeting is to tape it down at the aft edge of the spar cap. Fold it back while applying the glue then when you fold it forward it will be aligned.

[Dion Dunn]

ok, makes sense. I dont use the thick stuff much, so I may need to try that technique.

[ingrahal]

Update time:

Most people put the captions at the bottom of the photo so I'm going to change my format for that reason. It will also make the posting go a little smoother.




I aligned the trailing end of the ribs with the edge of the table so I could clamp the trailing edge balsa while gluing.



Gluing in the trailing edge shear webs. I cut the thin strips of vertical grain 1/8" balsa with the bandsaw.



Gluing on the 1/4" balsa leading edges with Titebond.



Shaping the wing tips.



Continued on next post....

[ingrahal]

That's it for now. Ailerons and spoilers next.

[ingrahal]

Update:
I've got both ailerons done now but not without some minor issues.
Here I have glued in the 1/8" X 1/2" balsa trailing edge.



I had to cut 2 rib ends for the inboard end of the ailerons.



Next I glued 1/16" X 1/4" strips to the top of the trailing edge and the leading edge of the aileron.



Here I have cut the aileron loose.


Continued on next post....

[ingrahal]

Update continued:


Using the belt sander to prep the aileron for the 1/8" X 1/2" leading edge.




After sanding.




Gluing on the leading edge.




Here is the left aileron with the control horn mounting plywood and hinges added.



Continued....