Scale 1/3 Scale Extra 330L Build.

[Snoopy1]

Pulled the two halves apart. Well I have used a number of ways but I must say using standard 3 inch wide packing tape. Great stuff the two halves just fell apart. Now all I have to do is get the tabs glued in and see how it looks and goes together.

 

[TonyHallo]

It is amazing how well one side of the sticks to everything, while the other side is so slippery. It's a wonder it sticks to itself?

 

[dhal22]

It is amazing how well one side of the sticks to everything, while the other side is so slippery. It's a wonder it sticks to itself?

Don't make me think too hard this early. Now I gotta figure that out.

 

[Snoopy1]

Got the tabs glued in on one side with hysol just have give it some time and then do the other side and then see if all the screws can pull the cowl back into shape, man I hope so.

 

[Snoopy1]

Well sitting in the shop waiting for the hysol to cure I started to look at the fuselage and then just started do some small parts as shown in the pictures. The one is the motor bulkhead being glued together and the other two pictures are the sides for the right side of the fuselage. Took a little bit of weight and some clamps to pull it together and close all the gaps.

 

[Snoopy1]

Ok I have a question this is about firewalls in large planes and that are flown a lot and for say 10 years. My problem is even when I have used top of line aircraft ply over the years the bolts loosened up and when you tighten them up again it just becomes a visious circle. Now I have used large washers on both sides and Thin CA until it would not adsorb any more. It all improved the situation but never resolved the problem. Also did the vertical carbon rod thing but that just turns into powder slowly. And also the firewalls are all coated in 50% thinned epoxy.
Ok let me clarify when I say loosened up it not that the nut has backed off it is that over time firewall has compressed and the motor has been able move a tiny bit and then from the motor vibration it all just wears out.

 

[Snoopy1]

Well worked on the other 6 connections for the cowl now just waiting for it to cure again, man bib not remember it taking this long. The ones that were done yesterday took 10 hours to cure. Did a little work on the motor box. Pictures will come later.

 

[TonyHallo]

I use tee nuts and red loctite, can't say that I've had any major problem, my Christen Eagle was built in 2005 and my One Design was built in 2008.

 

[Snoopy1]

Working on the the firewall and getting it set up it will be built into the plane with zero offset up or down or sideways. The plane recommended zero down but 2 degrees off to the right but I will leave it straight have been doing this for a while. I prefer tuning this out with the radio when I start flying. This way I can tune the correct amount and have a fixed amount that is not always correct for all conditions.

 

[acerc]

The problem with any wood is that it will compress under pressure. The trick is to tighten the bolts just enough to hold the engine but not enough to compress the wood. The pull from the engine is not enough to compress the wood unless it has already been started. Also need to make sure the bolt hole is a snug fit so as to not get any side play from vibration. The standoffs can also play a role in this as the bigger the engine the bigger the standoff's diameter needs to be. I cut my own from dowels and can range from 1" to 1-1/2". Since going to the larger dowels instead of the tiny aluminum ones I can also tighten the bolts up a little more without compressing the wood. On the back side of the firewall I use two extra thick fender washers one size smaller on the bolt hole and drill it to fit tight.