This is a flexi exhaust system.
How can I tie the can down?
Are tie straps available?

How hot do they get? I was thinking wire ties, but they are only good up to 100 deg C
This is an aluminium can, 267 x 60 diameter.
Maybe some insulation under the wire ties? What type of insulation?
That exhaust wrap tape could be a possibility? I will check SuperCheap Autos.

Maybe you could use some thin brass straps and bolt or screw it down.

i use plastic zip ties on my tuned pipes, been using them for years on my glow engines...is this on glow or gas?

you could also use to silicone fuel tubing around the plastic tie, does that on glow as well

Ditto on nylon tie straps. Only time I ran into problems was on nitro boats running 60% with the header cowled and not enough air flow. The silicone coupler will pop first though. On the pipe? No problem....

Dave Brown also makes a mount with a rubber O-ring.....

Quick Google Search: https://www.greathobbies.com/product...rod_id=BRO1060

I used 20mm i.d. teflon exhaust tubing on my .50ci glow methanol 2-stroke helicopters, plus silicone tubing over it at both ends (one single piece obviously works too) to prevent leaking: picture.

Prettig weekend Ron

Originally Posted by JimboPilotFL

Maybe you could use some thin brass straps and bolt or screw it down.

I have some 0.5mm (0.02") sheet metal here. I will have a look.

For sheet, you really need to wrap it round a buckle or rod of some kind and rivet it.
Then the buckle can be retained by two saddle straps.
Another way of doing it is screw into the side of a mounting block?

Possibly it needs some kind of cradle, too.

For a temporary test setup, I was thinking 6mm ply. (1/4")

I am sorting it out for a vertical crank axis, so the test version needs to go straight up about 20 inches.
I am testing in the conventional orientation.

I have a bit of el cheapo ply here, so I can make a 3-legged "Y"- shaped stand for it.

Originally Posted by RCpilot7974

i use plastic zip ties on my tuned pipes, been using them for years on my glow engines...is this on glow or gas?
]

you could also use to silicone fuel tubing around the plastic tie, does that on glow as well

The pipe is about 0.7L.
Gasoline/Petrol engine.
With a 61cc motor running into it, that is more than 10x the capacity.
The exhaust should be getting pretty cool after expanding 10 times. I think it exits at around 400 deg C, and 200 psi or so.
The final temperature in the muffler depends on the heat capacity of air , but should be down around the 50 degree mark.
I don't know if a smaller muffler runs hotter? - less area for surface cooling.
Definitely too hot to hold onto, but not instant sizzle heat.

I should check it with my infrared thermometer. - that was quite cheap, from AliExpress, I think.
I need to see if it still working!

I will try the wire ties for now.

not gonna lie, i dont have any gasser tuned pipe experience...based on personal experience, gassers do run hotter...lol the engine head burn and muffler burns are more painful than on glow engines...do let us know

I don't know where i saw them but somebody makes metal "zip ties". I guess a google search is in order.


Ken

Originally Posted by kenh3497

I don't know where i saw them but somebody makes metal "zip ties". I guess a google search is in order.


Ken

I have some 14 inch stainless zip ties on order, but I will keep them for airframe testing.
If the standard wire ties work, that will be good for the test-bench.

The gearbox will take a while to build and bench-test.

I have found that starting torque is a lot more than I thought it was.

I am upgrading my propeller centre cam-dog tube to 14-11mm wall stainless 1.5mm wall, or about 1/16"
The starting prop is directly driven by the engine, so the Delrin gears only have to take the output torque for one of the two props,
which is a bit less.

The starter nose seems to be standing up OK so far. The J-B weld is good at holding it together.

There is a guy in our club with a hobby shop that I noticed carries tie wraps with a coating on the inside. He specialises in the monster gas planes so maybe they are good for that purpose, or at least battery or tank hold downs. The picture sure looks like a quality strap. https://thunderboltrc.com/index.php?...rd=griplocktie They are reuseable which is a good thing.

I used stainless waterhose clamps with a narrow strip of rubber bicycle inner tube in between the clamp and muffler. You want some flex with the hold down system to compensate for the expansion and contraction of the muffler as it gets both hot and cold.