Using Studs to Increase Heat Transfer in Heat Muff

[Aggie78]

Originally Posted by civengpe

Not trying to be funny, but what about a heated seat like this? http://a.co/0g2naWs

Being from Houston, we usually fight the opposite problem.

Exactly what I have for the Missus...works good, complaints waaaay down...

[RV Jerry]

I bought a heated battery powered jacket for my friend who has no heater, he says works great, battery last for hours and it probably can be tied in to A/C power. Ordered jacket from Home Depot

[F1R]

Where are you feeding the air from? Low on the rear baffle bulkhead will let the cylinder fins pre heat the air before it gets to the heat muff.

Electric seats and electric snowmobile underwear are very effective and let you keep your head in cooler air.

[lr172]

Originally Posted by vetterman

Years ago I sent a tail pipe to another exhaust fabricating friend and he welded studs on the pipe for me. I tested the outlet air temps both before and after and there was no difference. At the time neither he or I had any data to know what it would do. He and I were both quite surprised at the results, so I'm saying from that test it's probably not worth the cost and labor.

Thanks for posting. Very helpfull to hear of actual test data. Maybe a bigger alternator is in my future.

Larry

[lr172]

Originally Posted by sibriggs

Wrap some safety wire around a pencil diameter size rod. Use the resulting coiled spring to wrap around the exhaust pipe under the heat muff. You don't want to use a regular spring because it will rust and break up, or a Bril?lo pad size wire as it will chafe and break up. Good old .040 safety wire.

Thanks Steve and Carl. Maybe I'll try stuffing something in there and see if it improves the heat output.

Larry

[lr172]

Originally Posted by WyoDave

Is your cockpit well sealed? Canopy, Stick boot, etc...? I live in western Wyoming and regularly fly in ground temps around zero. At altitude often well below zero. When I first bought my 6 it was unbearable at even 15 above. Sealed the canopy and it is perfectly comfy. Even my wife, who does NOT tolerate cold, finds it perfectly comfy in seriously cold temps.

Yes, cockpit is well sealed. Zero air from the canopy. Almost zero air from the spar area or footwell area. I have aileron boots and a fair amount of RTV sealing all sorts of little openings, including around the spars. I could have air from the baggage area, but I don't feel it.

The heat is fair, but had a few days around zero and could have used more heat. I am using a 1.25" restrictor on the air inlet and could consider opening that up a bit now that I have two muffs.

I also have no carpet or interior panels and I suspect the lack of insulation allows a very large amount of heat loss through the aluminum and plexi. The air near the cabin sides is MUCH colder than the rest of the cabin air.
Larry

[lr172]

Originally Posted by F1R

Where are you feeding the air from? Low on the rear baffle bulkhead will let the cylinder fins pre heat the air before it gets to the heat muff.

Electric seats and electric snowmobile underwear are very effective and let you keep your head in cooler air.

I am taking air from the rear baffle just above the fins on #3. I like the idea of taking air from the oil cooler, but can't think of a way to maintain enough pressure/velocity without some mechanism to switch from cold to warm weather (need more air flow through cooler).

I have seat heaters, but never used them. Pretty foolish on my behalf, but my alternator can't handle the extra load at lower (idle/taxi) RPMs. Therefore they are off at T/O and I always forget to turn them on once moving.

Larry

[Scott Hersha]

Be care with using steel wool, pot scrubbers, etc. inside your heat muff. Put a torch on the stuff first and see what happens. I've seen steel wool catch fire and burn like a sheet of newspaper with just a pass with a torch. You don't need that kind of heat!

[vetterman]

Ok guys, I see a lot of ideas being kicked around here, some good some well here's what I did years ago on my -4 to try to increase the cabin heat. I took one of those stainless pot scrubbers and neatly pushed, pulled, and prodded it into the heat muff. Yep, it did increase the temperature of the cabin heat. Seems it was about maybe 50 hours later, flying along happy as Jay bird when I noticed I was being hit with something coming out of the heater. I captured one of them and discovered it was little C shaped steel things. That's right, the heat deteriorated the pot scrubber and it was literally coming apart and attacking me. If I remember it wasn't a cheap one, I'm thinking it was a chore boy brand. It was removed from the heat muff, or what was left of it. So the next step was to close up all of air leaks, which really helped. I've always said that little leaky breeze that you can feel in the summer time, become an unbearable arctic blast in the winter time.

[ChiefPilot]

I used a couple of additional stainless steel hose clamps and some bits of stainless.

The hose clamps hold short L-shaped strips of the SS around the pipe, with the short end of the L sticking up vertically and with 6-8 of these things distributed around the circumference of the pipe. This whole thing is kind of a like a diffuser.

Two such diffusers are in place, just inboard the inlet/outlet openings of the muff. The screw for the clamp is inline with the inlet/outlet, and both serve to not only provide additional surface area but also to force a longer route for the air to take across the hot exhaust pipe.

Coupled with the cross-flow arrangement and a not-drafty cockpit, I'm pretty comfortable down to about -5ºF during a sunny day and perhaps 10ºF at night.

-Brad