Updates: New Bungee Truss and prepration for the firewall

We are making great progress. Last month I discussed the truss that was ordered from Steen Aero. The new one arrived and we began grinding to fit it into place.

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New bungee truss next to the old one to be removed

 

Some sheet metal tabs were grinded off to help fan out the firewall. If you remember a consistent mistake the previous builder made was not measuring to the center of the tubes. Now the airplane is about an inch smaller so everything has to be custom fit.

 

Progress…  January Summary (part 2 of 2)

As mentioned in the first part of the January Summary we had some issues with the new engine mount not fitting.

 

An engine mount jig was made and sent to Steen Aero for them to make a new engine mount.

screenshot-2017-02-23-20-19-40

 

Part of mounting the engine mount to the frame requires a ‘engine spool’ to be welded into the frame.

 

Here are the spools and where they need to be welded. Some of the diagonal tube needs to be cut for a nice fit.

 

Because I am building this airplane strictly for aerobatics, I am trying to save weight everyplace I can. My firewall was built out of titanium to save a few pounds.

Here is the new firewall:

 

 

We also closed up the longerons with steel plates. The edges were made chamfered so when/if the edges need to be grinded, it wont compromise the integrity of the weld.

 

Now onto the wing attachments. If you take a look at the plans the front wing fittings require the tab (flying wire attach point) to be bent to 26.45 degrees. The previous builder who I purchased the airplane from welded this tab on instead of bending it.

Here is a picture from  another builder that has encountered the same problem as me.

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Photo taken from biplaneforum.com

 

This is not good, especially because this need to be strong.

Here is a shot of the plans showing the bend radius and the new wing attachment ordered from Steen Aero.