The Ford Barn

The Ford Barn (https://www.fordbarn.com/forum/index.php)
-   Model A (1928-31) (https://www.fordbarn.com/forum/forumdisplay.php?f=3)
-   -   Stainless exhaust pipe rattle won't stop! (https://www.fordbarn.com/forum/showthread.php?t=228835)

James G. 09-10-2017 02:12 PM

Stainless exhaust pipe rattle won't stop!
 

I've not resorted to building a "modern rubber/hanger and those "clamps for stainless exhaust" only work for a short while.
QUESTION - what can happen if I just resort to the original clamp Ford used and just clamp the stainless pipe down??? does it put the manifold casting in danger of cracking???
So tired of that dadburn rattle and I'm not about to do away with my stainless exhaust!!

Dodge 09-10-2017 02:22 PM

Re: Stainless exhaust pipe rattle won't stop!
 

Stainless steel grows in length when heated as in the exhaust system. You need to figure
that in. The clamp needs to let it expand.
In some cars the exhaust will grow several inches.

Y-Blockhead 09-10-2017 02:28 PM

Re: Stainless exhaust pipe rattle won't stop!
 

Quote:

Originally Posted by Dodge (Post 1525450)
Stainless steel grows in length when heated as in the exhaust system. You need to figure
that in. The clamp needs to let it expand.
In some cars the exhaust will grow several inches.

Good morning, Dodge. Does S/S "grow" more than regular exhaust pipe? I don't have S/S exhaust, just askin' for my own knowledge and future reference. Thanks

eagle 09-10-2017 06:07 PM

Re: Stainless exhaust pipe rattle won't stop!
 

In general (10-6 in/in/ deg F)

Carbon Steel (1020) 6.7
Grey cast iron 6.7
Stainless (304) 10
Aluminum 13 Highest
Copper 9.3
Manganese-bronze 11.2
Titanium 5.0 lowest
Gold not listed in the book I checked

In reality these numbers are just guidelines, the thermal expansion of can vary quite a bit depending on the alloy. Silicone for instance reduces the thermal expansion of aluminum significantly. The thermal expansion rate also changes somewhat depending on the temperature of the metal.
(Googled)

Tacoma Bob 09-10-2017 07:08 PM

Re: Stainless exhaust pipe rattle won't stop!
 

MMMMM been runnin a S/S aries for years with a re-pop hanger. I did have to fiddle with it I bit but have run for years with no problems.

katy 09-11-2017 10:23 AM

Re: Stainless exhaust pipe rattle won't stop!
 

What does "In general (10-6 in/in/ deg F)" mean?

Jim/GA 09-11-2017 11:18 AM

Re: Stainless exhaust pipe rattle won't stop!
 

Quote:

Originally Posted by James G. (Post 1525447)
I've not resorted to building a "modern rubber/hanger and those "clamps for stainless exhaust" only work for a short while.
QUESTION - what can happen if I just resort to the original clamp Ford used and just clamp the stainless pipe down??? does it put the manifold casting in danger of cracking???
So tired of that dadburn rattle and I'm not about to do away with my stainless exhaust!!

I purchased an oversize muffler hanger with woven insulation inside it with my S/S muffler. That lets the tailpipe move when it gets hot but does not rattle.

Bratton's part number 7131. I'm sure other vendors have the same thing.

Nathan_1929 09-11-2017 03:15 PM

Re: Stainless exhaust pipe rattle won't stop!
 

Quote:

Originally Posted by Dodge (Post 1525450)
In some cars the exhaust will grow several inches.

No way, unless it's made out of rubber.

Quote:

Originally Posted by katy (Post 1525789)
What does "In general (10-6 in/in/ deg F)" mean?

Sounds like he's describing the coefficient of thermal expansion (CTE) for different metals. 10^-6 is scientific notation, and in/in is the unitless coefficient, per degree F. Another way of looking at it is as microinch per inch per degree F.

So, he's saying the CTE for stainless is 0.00001 in/in per degree F. What I'm seeing elsewhere is, based on the alloy of stainless, linear CTE is somewhere between 5 to 10 * 10^-6 /deg F.

What does this tell us? Someone should just measure their tail-pipe hot and cold based on a known datum and tell us how much it lengthens. I'd guess very little.

JBill 09-11-2017 03:19 PM

Re: Stainless exhaust pipe rattle won't stop!
 

Aries calls for care with a "not too tight" exhaust hanger even with the regular steel muffler, so apparently it's not just the stainless steel expansion they're concerned about.

brianpharmd 09-11-2017 07:49 PM

Re: Stainless exhaust pipe rattle won't stop!
 

I have a S/S Aries exhaust on my coupe and a standard Aries on my sedan. Both have the oversized tailpipe hanger for expansion. Both had the flimsy thermal cloth which lasted all of 100 miles. I bought some exhaust pipe wrap from the auto store. Not is as wide as the clamp but not very thick. I could it to fit the circumference of the clamp. Attached it with red RTV and let it dry. Then I attached the clamp with the pipe in place. Snug but still let's the pipe expand. Also rooming my rattle at the end of the tailpipe. Check Amazon for the exhaust pipe wrap. May be cheaper than the auto parts store. Send me a PM if you need pictures.

Brian

brianpharmd 09-11-2017 07:54 PM

Re: Stainless exhaust pipe rattle won't stop!
 

Quote:

Originally Posted by brianpharmd (Post 1526037)
I have a S/S Aries exhaust on my coupe and a standard Aries on my sedan. Both have the oversized tailpipe hanger for expansion. Both had the flimsy thermal cloth which lasted all of 100 miles. I bought some exhaust pipe wrap from the auto store. It is as wide as the clamp but not very thick. I cut it to fit the circumference of the clamp. Attached it to the clamp with red RTV and let it dry. Then I slid the clamp over the pipe and tighten in place. Snug but still lets the pipe expand. Also eliminated my rattle at the end of the tailpipe. Check Amazon for the exhaust pipe wrap. May be cheaper than the auto parts store. Send me a PM if you need pictures.

Brian

Auto correct/word substitutions on the tablet makes my post look atrocious. I fixed it in this post.

Chuck Sea/Tac 09-11-2017 11:26 PM

Re: Stainless exhaust pipe rattle won't stop!
 

I used some welded cloth

katy 09-12-2017 09:13 AM

Re: Stainless exhaust pipe rattle won't stop!
 

Nathan, thanks for the explanation, but I'm still confused.
I took high school math in the '50s and don't understand the "modern" symbols and ways of expressing mathematical equations.

midgetracer 09-12-2017 11:18 AM

Re: Stainless exhaust pipe rattle won't stop!
 

Katy what he is saying is that the pipe expands in length .000001 inches per inch/ degree F. this means that for a length of 10 ft (not a real measurement of a model A muffler) and a temperature increase of 100 degrees F (10 ft =120 inches) therefore, 120 inches X 100 degrees X .000001 =.12 inches expansion in length for the exhaust pipe and muffler. Not very much is it?

katy 09-13-2017 09:46 AM

Re: Stainless exhaust pipe rattle won't stop!
 

I understand co-efficient of thermal expansion, but what I'm trying to get my head around is what 10-6 in/in/ means.
10 minus 6 equals 4, that's pretty simple, but then what does in/in/ mean?

midgetracer 09-13-2017 10:53 AM

Re: Stainless exhaust pipe rattle won't stop!
 

something times 10 to the minus six equals moving the decimal point 6 places to the left.

Nathan_1929 09-13-2017 11:23 AM

Re: Stainless exhaust pipe rattle won't stop!
 

Quote:

Originally Posted by katy (Post 1526678)
I understand co-efficient of thermal expansion, but what I'm trying to get my head around is what 10-6 in/in/ means.
10 minus 6 equals 4, that's pretty simple, but then what does in/in/ mean?

"10^-6" is scientific notation for 0.000001. "in/in" is a way of saying "this is a unitless coefficient." Per degree is as stated.

That way, you can multiply your original length of material by a tiny coefficient specific to that material and arrive at what happens during a temperature change.

As midgetracer says;

The material expands in length .000001 inches per inch/ degree F.

Where CTE = .000001, x = 120 in, deltaT = 100 deg:

deltaX = .000001 * 120 in * 100 deg = .12 in.

To double check our logic, the units are:

(in/in /deg) * (in) * (deg) = (in*in/in)*(deg/deg) = in.

Makes sense.

But like I said several posts ago, someone should just measure the end of the tail pipe against a known datum at hot vs cold and see how little it actually moves.

dumb person 09-14-2017 04:14 AM

Re: Stainless exhaust pipe rattle won't stop!
 

A mild steel one moves about 5mm in my experience. Enough that it will permanently distort if the clamp was welded on and not the slip fit kind...

katy 09-14-2017 09:13 AM

Re: Stainless exhaust pipe rattle won't stop!
 

Thanks all for the replys to this old fart, I think I'm starting to understand this scientific notation stuff a little bit. I tried a web search and still didn't find much stuff in plain words that I could understand.


All times are GMT -5. The time now is 02:38 PM.

Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.