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Old 02-17-2014 | 12:36 AM
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GallopingGhostler's Avatar
GallopingGhostler
 
Joined: Oct 2004
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From: Clovis, NM
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Two attachments for some reason do not show up on my post. They are Attachment 1969333 and Attachment 1969334. Here they are:



The fuselage also has a slightly warped rear, wood had a natural bow in it. I will remove this when I plank the fuselage top and bottom.

A comment regarding choice of engines. The plans show a 1950's vintage Fox .09 Rocket side port engine on it. From various inputs, power from this vintage engine was .049 like. The engine was easy starting, but not all that powerful. Since I live in a windy part of the US, it didn't make sense to put in such a weak engine. The A.C. Gilbert (yes, the train folks) .11 Thunderhead I purchased from Tower Hobbies about 12 years ago has more power, akin to a mild .09 engine. However this model has a 46" wingspan and with the local windy conditions, felt a more powerful Enya .09 III TV would be the right ticket.

However, I wasn't careful to watch the fitment of Bulkheads F-1 for the engine and F-2 for the landing gear. These are close coupled. The combination of F-1 being about 1/64" narrower and F-2 being about the same wider resulted in doubler cheek cowl nose pinch of 1/4" (6 mm) less.

Titebond Aliphatic water based resin glue is great stuff. Unfortunately, once glued it stays glued. This reduced my choices of engines to either the narrower Cox .074 Queen Bee, or Thunder Tiger GP-07 Schneurle.

The Cox being a really long engine sticks out an additional 1.5" (48mm) beyond the cowling. Plus, it doesn't have a muffler pressure tap. This made the GP-07 a better choice.
Attached Thumbnails Click image for larger version

Name:	Berkeley Impulse Box.jpg
Views:	694
Size:	103.8 KB
ID:	1969393   Click image for larger version

Name:	Berkeley Impulse Box Art.jpg
Views:	847
Size:	246.8 KB
ID:	1969394  

Last edited by GallopingGhostler; 02-17-2014 at 01:52 AM. Reason: Added comments regarding engine choice