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Author Topic: Light mufflers  (Read 5279 times)

Offline Matt Piatkowski

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Light mufflers
« on: November 05, 2015, 06:47:36 AM »
Hello,
I am considering making light mufflers using the carbon composite mat and High Heat JB Weld.
As the engine exhaust temperature is, roughly speaking, in 260-350 deg. F range, High Heat JB Weld qualifies.

I am not sure, though, if such laminate will be strong enough not to crack due to vibration and internal pressure.

I would make two halves of such muffler having three layers of the carbon composite mat in the gypsum mold and glue them together, embedding the mounting nuts. The estimated wall thickness is 0.025 - 0.030".

Perhaps a thin aluminum wire can be wrapped in two or three critical places around such mufflers to reinforce them?

Does anybody have the practical experience in these matters?

Thank you,
Matt



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Offline Tim Wescott

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Re: Light mufflers
« Reply #1 on: November 05, 2015, 10:41:38 AM »
Some thoughts:

  • No I don't have practical experience directly with that.  I did grow up in a high-end fiberglass shop, and stayed interested, so I know a bit.
  • As long as the stuff retains some strength, I think it'll work.  An engine fire will be more hazardous to it than to an aluminum muffler, though.
  • There are some pretty light aluminum mufflers out there -- before you spend time on this you may want to get some data on the lightest ones.
  • Consider using cloth and roving, and maybe do it by applying the stuff to the outside of a wax plug, possibly even finishing it off by vacuum-bagging it.  When it's cured out at room temperature take it out of the bag and finish it off at elevated heat in an oven, melting out the wax at the same time.
  • If you don't hold the mounting nuts in a jig when you glue it up they won't be in the right place -- I'd at least think about putting solid aluminum inserts into the thing, then drilling and tapping the holes after
  • JB Weld is impressive stuff as far as the consumer market, but there's much better stuff on the industrial market.
    • I'd start by checking the fact sheet on the West Systems epoxy -- you may not need to go any farther than their layup resin
    • If not West Systems, then see what 3M and Loctite have to offer.  You may have to work to get your hands on it, but the industrial stuff can be way superior to the consumer stuff
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Offline Matt Piatkowski

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Re: Light mufflers
« Reply #2 on: November 05, 2015, 11:46:02 AM »
Hi Tim,
Thanks again for your thoughts.
Where are these "pretty light aluminum mufflers"?
Who has them?
Regards,
M
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Offline Tim Wescott

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Re: Light mufflers
« Reply #3 on: November 05, 2015, 12:09:24 PM »
The muffler that comes with the Tower 40.  There are other mufflers specifically made to be light, that I have held in my hand, but I can't recall any names.

Hopefully someone will chime in...
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Offline Dane Martin

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Re: Light mufflers
« Reply #4 on: November 05, 2015, 12:17:40 PM »
The lightest one i have used was a merco remake. Got it from eric at rsm. Give him a call and tell him your sizes. He might have some. Limited run though.
And i believe Randy Smith makes some tube mufflers that are much lighter.
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Offline Steve Helmick

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Re: Light mufflers
« Reply #5 on: November 06, 2015, 10:11:33 PM »
I'm a fan of Randy Smith's CNC Tube mufflers. I recall them to be about 1.5 ounces plus screws plus a rubber deflector, aka "Rubber Ducky". Check with Randy (our moderator) for price and sizes available. If you want a pressure tap, you need to add it yourself, like I did. Just aft of the split line, IIRC. Works fine.  randyaero at msn dot com   Give him the benefit of a few days to respond...and a good subject line.

Scott Dinger makes welded aluminum tube mufflers that are lighter and were the choice of Tom Lay. I have an address for him, weldit74 at yahoo dot com , but I can't say if it's current or not.

 H^^ Steve

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Offline Brad LaPointe

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Re: Light mufflers
« Reply #6 on: November 07, 2015, 04:32:57 AM »
Matt ,

See the combat guys . They are using carbon fibre mufflers . They stand up very well . Pat ,Yaro ,or Ivan probably can point you towards getting one built or how to do it .

Brad
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Offline Peter Grabenstein

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Re: Light mufflers
« Reply #7 on: November 10, 2015, 09:28:12 AM »
Hi all

Mr. Armand Kuentz /France is making excellent custommade lightweight mufflers for many F2B engines.
To my Memory, Richi Kornmeier and his Tom Lay ST 60V + Kuentz muffler.
Many month ago he made one tube muffler to fit my B.40 .
Excellent product with 42grams /1,5oz (no bolts) which is worth each Euro.
See pic. below, tube muffler OS LA 40/46 at 47grams / 1 2/3 oz. (no bolts).
You can reach Armand Kuentz @

a.kuentz@hotmail.fr

All the best
Peter  H^^

« Last Edit: November 10, 2015, 12:22:30 PM by Peter Grabenstein »
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Offline Matt Piatkowski

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Re: Light mufflers
« Reply #8 on: November 10, 2015, 10:29:01 AM »
Looks good and is light.
I am checking the price including shipping to Canada, brokerage fees and/or other custom related fees/charges/dues and taxes.

Knowing a bit how the Canadian border works, the additional costs associated with, how they call it "importing foreign goods to Canada from the non-NAFTA country" will be substantial.

Cheers,
M

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Offline Matt Piatkowski

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Re: Light mufflers
« Reply #9 on: November 10, 2015, 10:34:10 AM »
the e-mail address a.kuentz@hotmail.com does not work.
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Offline Peter Grabenstein

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Re: Light mufflers
« Reply #10 on: November 10, 2015, 12:16:46 PM »
Quote from: Matt Piatkowski on November 10, 2015, 10:34:10 AM
the e-mail address a.kuentz@hotmail.com does not work.

Sorry, my mistake, please try this one

 a.kuentz@hotmail.fr

Peter  H^^
« Last Edit: November 11, 2015, 12:35:05 AM by Peter Grabenstein »
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I don't care who your father is ......... as long as I fly here,
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Online Lauri Malila

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Re: Light mufflers
« Reply #11 on: November 30, 2015, 11:39:33 AM »
Hi.

Here is some pictures of my latest home-made muffler. Body lenght is about 150mm (5,9") and diameter 36mm (1,4"). End caps and baffle/side resonance chamber thingy are machined from barstock (Al#6262) and center tube is 1/64" wall thickness hard aluminium tubing.
Assembly with interference fit (resonator to tube), brazing (header & stinger) and JB-Weld (endcaps to center tube).
So it has 2 expansion chambers and one side-resonant chamber.
Total weight before polishing is 45g (1,59oz), I think that's very light for such an efficient muffler.

Lauri
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Online Lauri Malila

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Re: Light mufflers
« Reply #12 on: November 30, 2015, 11:40:27 AM »
Insides..
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Online Lauri Malila

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Re: Light mufflers
« Reply #13 on: November 30, 2015, 11:41:24 AM »
..insides..
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Online Lauri Malila

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Re: Light mufflers
« Reply #14 on: November 30, 2015, 11:42:04 AM »
..insides..
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Offline Target

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Re: Light mufflers
« Reply #15 on: November 30, 2015, 12:57:47 PM »
That's some awesome looking hardware right there!
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Regards,
Chris
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Online Lauri Malila

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Re: Light mufflers
« Reply #16 on: November 30, 2015, 01:40:16 PM »
You mean the Kostin F2A's in background?  :P
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Offline Target

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Re: Light mufflers
« Reply #17 on: November 30, 2015, 03:33:22 PM »
Oh, no, I'm referring to your creations. They look great.
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Regards,
Chris
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