Extreme Speed Prop Planes Discuss the need for speed with fast prop planes (Screamin Demon, Diamond Dust, Shrikes or any REAL sound breakin'''' plane)

How to keep exhaust out?

Reply

Old 08-07-2011, 07:34 AM
  #1  
_Tommy D
Thread Starter
My Feedback: (20)
 
_Tommy D's Avatar
 
Join Date: Feb 2004
Location: East Islip, NY
Posts: 683
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default How to keep exhaust out?

Guys

Normally I'm able to shim the mufflers low enough on my models that getting exhaust residue into them is not an issue. Not so on my Sig Kougar.

It has a 55AX and Performance Specialties muffler. I already have 1 extension on it to get it as far away the model as possible.

What I tried to seal the wing gap against the fuse is as follows:

Cleaned wing saddle on the fuse and applied a liberal amount of automotive RTV Red to area. I then installed the wing which was coated with wax paper and let it dry. Well much of the RTV stuck to the wax paper!

I'm open to suggestions as to weather I should have waxed the wax paper or what not.

Thanks!
Attached Thumbnails Click image for larger version

Name:	Nl31010.jpg
Views:	13
Size:	74.1 KB
ID:	1645493  
_Tommy D is offline  
Reply With Quote
Old 08-07-2011, 07:53 AM
  #2  
gltruett
My Feedback: (23)
 
Join Date: Jun 2002
Location: Woodstock, GA
Posts: 99
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to keep exhaust out?

Tommy,

I do pretty much as you did but I use saran (plastic) wrap rather than waxpaper and I've never had it stick. I just use the cheap white or clear RTV, not the red stuff. Cut off a too big piece of the plastic wrap, stretch it over the wing until all the wrinkles come out and tape with masking tape on the edges. Put a good bead of RTV on the wing saddle, don't worry if it oozes out when you bolt the wing on, you can trim it with a new razor blade after it cures (give it 24 hours or so). You could also use one of the little exhaust diverters on the end of your muffler to direct it away from the wing saddle.
gltruett is offline  
Reply With Quote
Old 08-07-2011, 08:03 AM
  #3  
_Tommy D
Thread Starter
My Feedback: (20)
 
_Tommy D's Avatar
 
Join Date: Feb 2004
Location: East Islip, NY
Posts: 683
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to keep exhaust out?


ORIGINAL: gltruett

Tommy,

You could also use one of the little exhaust diverters on the end of your muffler to direct it away from the wing saddle.
It blew off about 5 seconds into the flight The muffler leaves very little for it attach too.

Yep that RED RTV stuck like glue to the wax paper. I wonder if I coat it with oil if it would have made a difference.
_Tommy D is offline  
Reply With Quote
Old 08-07-2011, 08:21 AM
  #4  
speedracerntrixie
My Feedback: (29)
 
speedracerntrixie's Avatar
 
Join Date: Jun 2010
Location: Sacramento, CA
Posts: 6,794
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to keep exhaust out?

Tommy, if the wing is covered in Monokote or Ultracote, you can simply wax it with carnuba wax. Do not buff it off just leave a thin film and then use clear RTV. The RTV will not stick to the wax.
speedracerntrixie is offline  
Reply With Quote
Old 08-07-2011, 04:47 PM
  #5  
stall_warning
Member
 
Join Date: Sep 2006
Location: Mountain Top, PA
Posts: 33
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to keep exhaust out?

I was able to attach an exhaust deflector to a TT muffler that does not have the milled ridge like the OS muffler. I pinned the
deflector in place. Drilled a 1mm hole thru the deflector and muffler while the deflector was in position. Used music wire control
rod from one of those small electric planes, it was 1mm. You can then bend the ends over like I did or maybe cut it flush
and use a Ty rap to keep it in place. The trick was to drill straight and not break the bit. So far, it's still on.
stall_warning is offline  
Reply With Quote
Old 08-08-2011, 10:04 AM
  #6  
bob27s
My Feedback: (19)
 
bob27s's Avatar
 
Join Date: Apr 2002
Location: Cleveland, OH
Posts: 5,576
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to keep exhaust out?

just as a reference,

The Kougar and King Kobra were both originally configured with a 30deg engine, not fully side mounted.

They did that so the muffler would clear.

http://www.jettengineering.com/hall/...k-nose-300.jpg
Attached Thumbnails Click image for larger version

Name:	Ge96908.jpg
Views:	9
Size:	114.0 KB
ID:	1646027   Click image for larger version

Name:	Up48788.jpg
Views:	9
Size:	109.2 KB
ID:	1646028  
bob27s is offline  
Reply With Quote
Old 08-08-2011, 10:10 AM
  #7  
bob27s
My Feedback: (19)
 
bob27s's Avatar
 
Join Date: Apr 2002
Location: Cleveland, OH
Posts: 5,576
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to keep exhaust out?


ORIGINAL: gltruett

Tommy,

I do pretty much as you did but I use saran (plastic) wrap rather than waxpaper and I've never had it stick. I just use the cheap white or clear RTV, not the red stuff. Cut off a too big piece of the plastic wrap, stretch it over the wing until all the wrinkles come out and tape with masking tape on the edges. Put a good bead of RTV on the wing saddle, don't worry if it oozes out when you bolt the wing on, you can trim it with a new razor blade after it cures (give it 24 hours or so). You could also use one of the little exhaust diverters on the end of your muffler to direct it away from the wing saddle.

Use monokote backing plastic. Works great for silicone potting release.

I do my wing saddles with clear GE silicone all of the time. Very little bit goes a long way.

bob27s is offline  
Reply With Quote
Old 08-08-2011, 11:23 AM
  #8  
jaka
 
Join Date: Dec 2001
Location: Upplands Vasby, SWEDEN
Posts: 7,788
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to keep exhaust out?

Hi!
To have a thight wing to fuselage fitting you use 24 hour epoxy and brown micro balloons!

Just put on some masking tape on the wing center. Wax the tape surface with carnuba wax (not car wax). Mix 24hour epoxy with brown micro balloons and put on the fuselage wing sadle. Bolt the wing to the fuselage and wait 24 hours!

Silicone is no good!
Attached Thumbnails Click image for larger version

Name:	If10757.jpg
Views:	8
Size:	22.6 KB
ID:	1646056   Click image for larger version

Name:	Pk31785.jpg
Views:	9
Size:	29.1 KB
ID:	1646057   Click image for larger version

Name:	Wb77042.jpg
Views:	7
Size:	42.5 KB
ID:	1646058   Click image for larger version

Name:	Jd88547.jpg
Views:	5
Size:	57.5 KB
ID:	1646059   Click image for larger version

Name:	Ep85496.jpg
Views:	10
Size:	73.0 KB
ID:	1646060   Click image for larger version

Name:	Yw68063.jpg
Views:	11
Size:	34.9 KB
ID:	1646061  
jaka is offline  
Reply With Quote
Old 08-08-2011, 06:14 PM
  #9  
_Tommy D
Thread Starter
My Feedback: (20)
 
_Tommy D's Avatar
 
Join Date: Feb 2004
Location: East Islip, NY
Posts: 683
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to keep exhaust out?

I wanted to thank you guys for the suggestions once again.

I just applied some GE Brand clear silicone and tried wax paper once again. If this also sticks to the wax paper I guess Ill pick up some saran wrap or the likes. The idea to use backing from film covering was GREAT! However being a pack-rat it means now Ill have even more "junk" taking up shop space.

The Kougar is a old one, and fly's as well as say a old pair of boots fit. I hesitate to change the engine orientation for that reason. What I might try is to use the evolution/Jett style muffler as it's got a longer flange standoff then the Ultra-thrust style one.

Some aluminum tape creatively applied could also act as a Ruth Goldberg exhaust deflector as well =)
_Tommy D is offline  
Reply With Quote
Old 08-09-2011, 06:39 AM
  #10  
landeck
Senior Member
My Feedback: (1)
 
Join Date: Nov 2007
Location: Sandy Springs, GA GA
Posts: 1,710
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: How to keep exhaust out?

One trick to help the silicon adhere to the wing saddle is to drill a lot of shallow small (1/64") holes in the wing saddle so that the silicon has something to help it grip the saddle.

Bruce
landeck is offline  
Reply With Quote

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service