warped horizontal stab
#1
Thread Starter

Joined: Aug 2007
Posts: 178
Likes: 0
Received 0 Likes
on
0 Posts
From: Indianapolis,
IN
I just got my horizontal stab done to find out the trailing edge is warped.. one side is level and the other curves up about an eight of an inch.. my thought on fixing it was to cut a scrap piece of balsa in the correct shape to level the trailing edge. any insight.. FYI this i my first kit.. built many arfs
#2
What is the total length of the stab? Is it attached to the plane already and is it solid slab balsa or built up? There are ways to correct based on your answers. Is the trailing edge up or down the 1/8" with regard to the leading edge. Is it solid slab balsa or built up. This can be fixed based on our answers however I don't think 1/8" is anyting to worry about.. Just my opionon but may cause very minor trim issues.
If the stab is built up.. be sure you correct the whatever caused that to start with before working on the wing.. Not level table.. loose pins, etc...
Mike
If the stab is built up.. be sure you correct the whatever caused that to start with before working on the wing.. Not level table.. loose pins, etc...
Mike
#3
Senior Member
Joined: Jun 2006
Posts: 129
Likes: 0
Received 0 Likes
on
0 Posts
From: Johannesburg, SOUTH AFRICA
Cover it , then heat and hold in shape while covering cools down. Should Fix the warping.
Thats the way i fixed my Ailerons that came warped out of the box
Thats the way i fixed my Ailerons that came warped out of the box
#4
Thread Starter

Joined: Aug 2007
Posts: 178
Likes: 0
Received 0 Likes
on
0 Posts
From: Indianapolis,
IN
i have completely finished the horizontal stab.. it is not onthe plane and i was looking to make the elevator and noticed the warp.. i would have half the elevator larger than the other.. being my first kit and a patient person, i was thinking of engineering that shim to make it level
#5
Thread Starter

Joined: Aug 2007
Posts: 178
Likes: 0
Received 0 Likes
on
0 Posts
From: Indianapolis,
IN
its approx. 14 inches long and a single piece of balsa. if its any help, im building an elder 40.. the elevator is flat against the table but the leading edge and trailing edge are not paralell
#6

Joined: Apr 2006
Posts: 469
Likes: 0
Received 0 Likes
on
0 Posts
From: Scappoose, OR
Hi: I have had a similar problem with warping of solid wood pieces, and solved the problem by purchasing a better piece of wood to make a new piece. In your stage of construction, this would be an easy move to make, and would cure the warp from returning after it was installed.
Rich S.
Rich S.
#7
like aerorich says you can purchase a new piece or lightly mist the current piece and bend 1/8"in the opposite direction where it occurs and let sit for a bit. Since it's a solid slab it will be difficult to get the warp out with heat and covering but could be done. If you gently mist and bend opposite.. check every 1/2 hour or so so you don't end with a warp in the opposite direction. I just looked at a pic of the horiz stab.. this would be easy to straighten out as the width is quite small at the tip.
Mike
Mike
#8
Hi, I'm building a GP super skybolt, and also working on the horizontal stab. I am using aliphatic wood glue to glue the sheeting. And using a flat surface I glued it and set a bunch of magazines on it and let it dry overnight. I noticed that my stab was warped after I put the sheeting on one side. Thinking it would go away as soon as I sheeted the other side, I went ahead and glued the sheeting on the other side. The warp/bow is still there. (How can I fix this when both sides are sheeted and not glued to the plane yet? Thanks, Grayle
#9

My Feedback: (2)
When I have ran in to this condition, I just built a new one and discarded the warped one. It is a stab which is not like have an entire wing panel. The time, effort and money even in a built up stab is not so much. It is better to have a true plane that can be avoided early on than something you won't be happy with months and years down the road.
#10
Senior Member
My Feedback: (5)
Joined: Jan 2002
Posts: 2,025
Likes: 0
Received 0 Likes
on
0 Posts
From: Tulsa, OK
After a surface is sheeted it is almost impossible to remove a warp with out removing the sheeting. Sheeting a surface is a good time to put a warp in or take one out. I never had much luck removing warp from a solid piece of balsa and usually replace it if it affects the airfoil shape.




