I was flying my Sun Dancer this afternoon, but the winds came up pretty strong during my second flight. I had my first landing on the mains, smooth as silk, great plane. In taking the plane apart, both interplane strut fittings on one wing half were broken. Has anyone experienced this before? The plane has been flowning pretty gently, mainly on low rates.

I'm thinking of making eight of them out of regular bolts like mikemnh did for the two cabane strut fittings that were failing when the Sun Dancer first came out. http://www.rcuniverse.com/forum/m_19...tm.htm#1950965

Anyway, check yours frequently.

Actually, yes, I have heard about it, but not for quite some time. In the original first batch or two released there were some strut failures, none that actually crashed any planes that I ever heard of. Most of the stories were very similar to yours, which makes me think that you might want to find out when it was produced. Perhaps more importantly, you may wish to contact Sig Manufacturing about it, as I'm sure they'll be happy to make sure you have the upragraded parts needed to take care of that.. They've always been right there for everybody I know of who ever had a problem, and I recall they were also there for the guys who had a few failures during the early release of the Sun Dancer ARF. Also, I'll bet there are still some threads about that you can find from a year or two back that would give you more up-to-date information. Mine was ordered out of Sig later on so the upgrade was already done. (But I haven't flown it yet so I may be talking out of my b^tt !!) Anyway, I do remember that exact type of problem, so some research may be in order for you.

Good luck! Let me know how it goes.

Jim

TO WING BLOWS OFF SUNDANCER

I just got finished writing a long winded post about a top wing blowing offf a Sundancer today at the field. I click on it to post and it timed out and I lost the whole post Shame on Sig with the piss poor cabane strut bolt design. Changed to the modded bolts and they pulled out of the blocks taking off the top wing and pulled out off the lower wing interplane struts breaking the lower wing in half and the plane went in. Piss poor design

First, I don't have a clue how the struts are attached on a Sundancer, so if I miss something here forgive me.

A few big bipes in the last three years or so have been produced with what I consider to be extremely sub-standard methods for attaching fittings, struts, cabanes, and strut to wing attach points. Some have had as little as a small hardwood block that a simple sheet metal screw was used to make a structural attachment of a critical component. Some didn't even have the hardwood block, but simply suggested that the balsa be hardened with thin CA to harden the threads cut by the sheet metal screw.

This goes against everything that has been developed by modelers over many, many years of biplane building and flying. Yes, you can join two objects with a simple machine screw and nylock nut but you have to have something solid in the middle to be attached. Buyers should be looking for hardpoint inserts such as "T" nuts set onto hardwoods for a strong and lasting attachment point. Hard ply tabs, not bamboo/luan ply, for "I" struts is something else to look for. Aluminum angle brackets that are attached via a machine screw into a blind nut is another method of attachment.

Until we as modelers stop purchasing products designed to self destruct industry changes will not be made. Look at this stuff before you make that purchase decision every time you can. If it does not look like is designed with long term strength in mind, don't buy it and tell the dealer why. That happens enough and changes will begin to happen. If you get something that clearly was not designed with structural integrity in mind, then make the changes that need to be performed before you fly it. Not doing so sets the stage for a crash at a time and place yet to be determined. You may not be able to control the aircraft well enough to avoid serious injury to yourself or others when it happens. And it WILL happen!

I have every intention of calling Sig in the morning and voice my opinion of the very poor design of the cabane strut fixtures. I think they really should replace the plane.

You know, I just realized I'd never know whether there was some problem with the Hog Bipe because I rebuilt my cabanes to make them custom and pretty, I used lite-ply sandwiched between two sheets of balsa and rounded the edges and made custom fasteners. Maybe I should give my Sun Dancer Bipe ARF the same treatment so that I won't have to worry about it.

I'd give SIG the chance to make good on things, I think you'll find that if you give them the information that they'll be good to you. They've been around a long time now, they didn't last this long by not taking care of things. Just a suggestion.

Jim