I just purchased a rambler 45. This is my first arf build I am doing good with the build so far but I am stuck at one point. Are their any tricks to lining up the horizontal stabilizer correctly as it looks like there is very room for error and if I am off by just a bit I can’t get my elevator on. When I do this I will be working with epoxy so my time is limited. Any help would be great.

Best,
ROb

Hold the elevators up against the rear of the stab and make a mark on the stab trailing edge where the inside end of each elevator is. That will give you two marks near the center of the stab about 3/4 or 1" apart. As long as the rear of the fuselage is in between the marks, your elevators will work.

Dry fit it first and then when you are happy with the fit, use 30 Minute Epoxy.

Jim

The plane has a tight fit, use CA, epoxy is a nightmare as you need to slide the stab through the fuse!

Hmm tIANci, I have never heard anyone using CA for the hor. stab... I'd like to know if others employ this method as well. Putting in the rear stab is always the most frustrating of tasks as it you usually have to wipe off a ton of epoxy and align it just right.

Normally I will dry fit the stab in, then get a peice of string (I use string they have in Asia that is not elastic). Line up the stab and mark all the right lengths. Basically the string should be marked for the distance between the end of the stab along the trailing edge to the fuse and another mark for the same point on the stab to the middle of the firewall. Of course you should make sure that they are perfectly aligned so that these two marks will be able to line up your stab. Then use 30 min epoxy. I always have a bottle of alchohol and some tissue nearby to wipe away any additional epoxy.

If you align the stab up perfectly, the elevators shouldn't be a problem. If they are, trim the elevators is probably better than misaligning the stab.

Good flying!

Ok I know I am going to sound like an idiot but I really don't want to screw this up. I took my plane to my lhs guy and he told me to measure the center of my firewall. well I did this but it is not exactly center in relationship to the top of my fuse. I know I need to measure the tips of the H stabilizer to the center of the fuse by the firewall but since the fuse is curved how do I get this center point. I feel like this should be easy but I am really confused and know matter how I measure it just dos not look center please help.

Rob

There is an easier way to do that.

First mount the wing, following the instructions.

Then dry install the stabilizer, making sure that the stab is centered from side to side and is parallel to the wing, looking from the back.

Measure from the trailing edge of the wing straight back to the trailing edge of the stabilizer (not the elevator) at the tips and be sure they measure the same on both sides.

Draw lines along both sides of the fuselage on the top of the stabilizer as a guide.

Now glue the stab in place and check both alignments (from the rear and from the top) frequently until the glue sets up.

Jim

"Measure from the trailing edge of the wing straight back to the trailing edge of the stabilizer (not the elevator) at the tips and be sure they measure the same on both sides."

Ok so am i mesuring from the trailing edge of the wing tip to the tip of the stablizer or straight from the stabalizer tip to the trailing edge of the wing?

Thanks for your help.

Sorry for the dumb question.

Rob

Straight forward to the wing.

"Dumb" questions are a lot better than dumb mistakes.

Jim

ok I did what you said much easyer but my concern now is that when I measure from what I think is the center point it seems off by a little more then a quarter of an in. (I no my center point might be off though) I am just nervous because this is my first build just wandering what is my margin of error (if any) if things are off slightly. My other concern if the manual tels me tho check my wing alignmeant by measuring from the the rudder to the farthest inner corner where my ailerons are this seems to be of by almost a half inch the strange thing about this is that the wing can only go on one way and I can't see how I could have screwed this off. I am just waiting for a reply before I epoxy it all up.

Thanks

What "center point" are you talking about?

Your margin of error on all of these measurements is probably about 1/8" before a really good pilot could tell the difference by flying it.

Jim

Hi Jim, thanks for your reply. If you look at the link go to the bottom of the page you will see in the bottom right the center point that I am talking about in the front of the plane. I see no easy way to find dead center as the fuse is curved anf if I just mesure across the fire wall for center it seems off center. Your method seemed to work fine but I just want to make sure I don't have any problems before I do the final epoxy. Thanks for all your help it is greatly appreciated.

http://www.theworldmodels.com/para/i...on/a099/p4.pdf

Robert

I just checked again and the wing is off by slightly more then a quater of an inch at the wing ip. It seems to me that the wing is quater of an inch foward on one side. Will this be a problem if I am mesuring the stabalizer to the wing. Or will this be acceptable and be able to be trimed out in flight.



My above post shows the manual and what I mean by center line.

sorry for all the questions

Best,
Rob

I don't think it's a big deal quarter of an inch can be trimmable. Just make sure that you leave enough trim in the TX. Remember to make all your control serfaces neutral without using the trim. This allows you the full trim travel for the first flight.

And, let someone take it up that has a lot of experience, I can pretty much fly a crappy plane without too much of an issue. I mean, I had a plane that continued to roll at about one roll every 3 seconds even with full reverse trim and still brought it down safely.

since the wing is off should I be measuring from the stabilizer leading edge at the tip straight back to the wings leading edge or to the front top center of the fuse. I like the first way the best the other way I can not seem to find an easy way to determine the front center of the fuse since it is curved the easiest way seems to be to eye ball it.


[&o]

Best,
rob

Rob:

The most important alignments are between the vertical and horizontal tail surfaces and the wing. The fuselage to wing and fuselage to tail alignments are not nearly as important. Since the wing will only go on one way, align the tail to the wing and ignore the fuselage. That 1/4" you're talking about won't matter at all.

Jim