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Building Tips and technical articles. => Building techniques => Topic started by: jim gilmore on March 28, 2009, 04:47:46 PM

Title: Profile construction....??
Post by: jim gilmore on March 28, 2009, 04:47:46 PM
I have 2 quetions on the qaakromaster I'm building.
First question is that when I glued in the engine mount blocks I first glue the blocks in and leave the doublers off. I do 1 at a time.On the lower block the mount doesnt fill the space so I took heavy card stock type paper. cut it folded it and  epoxied it all together. I'm guessing that filling the space is better than a void?

My second question is that I'm considering adding a smallish false cowl? like the shoestring has . would that help with strength and vbration ?
Title: Re: Profile construction....??
Post by: Alan Hahn on March 28, 2009, 07:33:53 PM
I think you were right to fill the void--but I would have stuffed in some thin slices of balsa--however yours probably will be as strong--maybe even stronger.

A cheek cowl would look nice. I'm not sure how much strengthening or vibration dampening you need with these newer 2 stroke engines (FP, LA, or Thundertiger 10-15's). They already run pretty smoothly compared to the older iron piston engines.
Title: Re: Profile construction....??
Post by: Leester on March 28, 2009, 07:36:45 PM
As far as the motor mounts, normally test fit and if any gaps fill with balsa. Gaps are usually there to fit different size engine cases.
Title: Re: Profile construction....??
Post by: Wynn Robins on March 29, 2009, 08:03:29 PM
A tripler (cheek cowl) will add strength - to add to the vibration dampening - extend the "cowl" back and fix it to the leading edge sheeting- this will help transfer any vibration back through the airframe