I know that your not supposed to have twist in the hor stab.  Well I do.  How much would be  acceptible?  Im not gonna tell you how much I have until you tell me how much is too much :)

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I'm having this very issue with an elevator I bought completed from a former builder. The tolerance for twist allowed is 1 degree per the construction standards. I spent 5 days riveting and unriveting the elevator. It has been difficult to isolate the cause but it appears that, in my case, the uneven application of the skins on one side created the twist in the spar on that side. I removed half by replacing nose skin, the remainder will have to be removed by replacing repeat skin. I'm determined to win this battle.

So I can lay my stab flat side down, when I push on one corner the opposite front corner moves.  I am within spec according to standards but I dont like it.  Is this the way to check for twist?

I was close to spec, didn't like it either. That is how I measured my twist. The constr standards show a small image of an example of twist and direction of measurement. I ordered a new rear skin and two rear ribs today for correcting problem.

I may drill out rivets on one side to see if I can pull it out.  If I cant get it closer I will live with it for now.  I will install on the plane and if it flys hands off ill leave it on.  If it causes problems I will order a factory kit for stab.  Thanks for the replys.

By the way mine moves up about 5 mm. Whats your do?

Approx 10 mm, I would live with 5 though and do as you plan on doing.

how much have you gotten out by drilling the rivets and reriveting?

more than half but I reached a point where I ran out of maneuvering ability and decided to replace the rear sheet and two inner rear ribs. The original builder must have had a bad day when putting it together. 

I'm sure ill find this out in the plans somewhere, as I'm only at the rudder, but how do you find out how much twist there is? Do you use some sort of 180 degree plate with degree markings up against the spar?

The construction standards specify 0 degrees twist but 1 degree allowable max, which is not much. I would not bother with attempting to measure it as much as I would ensure everything was very flat and continue checking throughout the process until riveted. In my opinion, you have to be almost careless going too fast to miss it when building from a kit, easier to get in trouble when building from scratch.

In the plans you will see that the rudder gets laid down on some 2x2 pipe.  On one end of the rudder you need to put a spacer under it and that will keep the twist out.  I will definitly pay more attention to twist.

Yeah, I saw the spacer, and am almost done with the rudder and have been using the spacer while I was building it. But, how do you see twist in the wing or horizontal stabilizer? What is the gauge or tool that allows you too measure twist? What is it relative too? The bottom of the leading edge and the rear of the wing? Do you use a protractor to draw and measure the angle or is there a gauge or tool like a square?

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