Baffles on a 2.6 Yak.

[notorious_benny]

With summer looming around the corner and a good 12 months of hard flying on my Comp-ARF Yak I have decided that just bolting the motor in the cowl does not provide enough cooling air. So I have decided to bite the bullet and finally baffle the sucker.

Now I will admit I am not much of a builder, and can sit and scratch my head for hours on end and an idea will never pop into my head. So I decided to copy an existing idea.

Since there isnt many threads on the Giants covering baffling I thought I would start one and prove that even a crook backyard builder like myself can 'hopefully' do the job. The idea I have plagerised from a thread on RC universe, the only difference is that I wanted to work with balsa.

I have looked at countless different pictures of baffle set ups on round cowl models and decided that I wanted to try and build a 'shroud' style baffle that will force as much air as possible over the motor.

Well here we go...... first off I grabbed the nose cowl to use for sizing and then found a nice flexible pice of 4" x 1/16 sheet of balsa. Using heaps of water and going very GENTLY I shaped the balsa sheet into my 'shroud'.

[notorious_benny]

Then using the missus's hair dryer I dried out the wood and the glued the overlap together with a little bit of CA.

Once dry and 'workable' I then lined up the 'shroud' over the cowl and tacked it on with a little CA for the moment. Realising that I need to get a hand in the cowl for the choke and also for the 'zip ties' that hold the cowl pice together I cut out the shroud at the bottom.

[RustyTumbles]

Looks good benny,

keep it comming this is a very interesting topic for us Aussies and all other who fly in hot environments.

[notorious_benny]

Now I take my cowl piece and simply through trial and error fit my first 'deflector' I spose you could call it, once I was happy with its position I simply glued it in with a little CA. And voila the baffles are fitted!

Of course I intend to use some epoxy to glue it all down firmly, I am also going to use some thinned epoxy to 'treat' the 1/16 balsa sheet and then I have to think about what colour I will paint it, though it seems that black is all the rage from what I have seen.

If anyone has any ideas on how I could baffle the lower half of the cowling while still maintaining access to the choke and keeping the tuned pipes cool please let me know. LIke I said I am a mug builder and ideas dont come easy

[RustyTumbles]

One side sit slightly higher than the other is there a reason for that?

[notorious_benny]

Yeah, like I said I am dodgy! Seriously though the cowl isnt bolted on fully in that shot and I havnt finihed sanding everything yet.

[RustyTumbles]

Thats cool, just curious. I think painting the baffles black will look the best.

[airborneSGT]

Do you think you need the baffles for a non tuned pipe DA 100 in the same plane? I am just starting to put together my yak with a DA 100 and also live in a hot environment. I also notice that you have the CF carb plate. I am guessing you also needed that to get the DA running right.

[notorious_benny]

Yeah, under the carbon plate I have a little pice of aluminium drink tin bolted really close to the diaphragm plate. This stops the motor richening as it accelerated during the takeoff roll. Simple, and works a treat.

I would say yes, definitely baffle it no matter what pipes you run. Your motor will last longer, as well as make better power. I used to run standard stacks and they kept the heat in close to the back and bottom of the cylinders. And that is were the motor is most noticeably 'pinking'.

[always flying]

Thats great man!!

I've been meaning to fab something up for my yak 55.... but been scatching my head for a while over it!..good job!! this will give me a good start!

cheers!

mannyh

[SBR_RV]

keep it up benny!

[notorious_benny]

More to come tonight. Just been shopping for some epoxy and some black paint. Will try and get it finished up tonight.