Exhaust lagging

[Wrinkley]

Its time to fit some exhaust lagging to my engines exhaust. Now I'm sitting at home and want to go and get some lagging tomorrow so I can fit it at the weekend. I am sure the sensible thing to do is wait till the weekend, measure it, and buy some next week. But... I'm not really like that 'cos I'll still get it wrong. So how much have you used? My 2"1/2 or 3" pipe comes out of the engine along a bit round a bit then goes up. Enters the silencer 5"diameter (ish) for a couple of feet then goes back to a pipe for six or so inches then out the roof. I have not uses a tape measure on this, can you tell?

 

I have done a search on the forum and know the perils of diesel soaked lagging or securing it with cable ties but so far no help with length.

 

Any help, to the nearest meter or mile, would help.

 

Regards

 

Wrinkley

[alan_fincher]

Its time to fit some exhaust lagging to my engines exhaust. Now I'm sitting at home and want to go and get some lagging tomorrow so I can fit it at the weekend. I am sure the sensible thing to do is wait till the weekend, measure it, and buy some next week. But... I'm not really like that 'cos I'll still get it wrong. So how much have you used? My 2"1/2 or 3" pipe comes out of the engine along a bit round a bit then goes up. Enters the silencer 5"diameter (ish) for a couple of feet then goes back to a pipe for six or so inches then out the roof. I have not uses a tape measure on this, can you tell?

 

I have done a search on the forum and know the perils of diesel soaked lagging or securing it with cable ties but so far no help with length.

 

Any help, to the nearest meter or mile, would help.

 

Regards

 

Wrinkley

No idea about length, other than when I re-wrapped just the pipe nearest the engine on mine, (not the "box" at all), I thought I had bought more than ample, but was amazed how fast it got used.

 

The other warning, is that I did it unprotected, and it brought my skin up in a far worse rash than I have ever got from say fibreglass loft insulation.

 

My strong advice, unless you are bullet-proof to such things, is to wear good protection, and try and avoid much skin contact.

[Marky_Mark]

get about 100 metres, you should have enough then !!

[alan_fincher]

get about 100 metres, you should have enough then !!

£2.29 per metre at Midland Chandlers.

 

So about two hundred and thirty quid, then ?

[RobinJ]

Its time to fit some exhaust lagging to my engines exhaust. Now I'm sitting at home and want to go and get some lagging tomorrow so I can fit it at the weekend. I am sure the sensible thing to do is wait till the weekend, measure it, and buy some next week. But... I'm not really like that 'cos I'll still get it wrong. So how much have you used? My 2"1/2 or 3" pipe comes out of the engine along a bit round a bit then goes up. Enters the silencer 5"diameter (ish) for a couple of feet then goes back to a pipe for six or so inches then out the roof. I have not uses a tape measure on this, can you tell?

 

I have done a search on the forum and know the perils of diesel soaked lagging or securing it with cable ties but so far no help with length.

 

Any help, to the nearest meter or mile, would help.

On the occasions I have had to take mine off, its always shorter when it goes back!

If its 3" diameter and the lagging is 3" wide then you will need 9" for each width of lagging, so if the pipe is 3' long you need at least (12 x 9) 9' of lagging!

[bottle]

Did you allow for the overlap?

[WotEver]

On the occasions I have had to take mine off, its always shorter when it goes back!

Funny that - mine shrunk under exactly the same circumstances.

 

Tony

 

If its 3" diameter and the lagging is 3" wide then you will need 9" for each width of lagging, so if the pipe is 3' long you need at least (12 x 9) 9' of lagging!

Plus another 50% for overlap?

[Bimbly1]

I bandage the lagging on with two round turns to anchor and the about a 50% overlap. Bends require a bigger allowance. At the other end I leave sufficient length to enable me to cut the lagging down the centre for several inches, tie a knot at the closed end of the cut and then wrap the two parts in opposite directions around the pipe and tie off. On mine, If IRMR I found that about two feet of ?4" lagging covered about nine inches. But it was a couple of years ago, I didn't measure it to closely 'cos I didn't know I was going to be asked.

[Matthew Knowles]

What does lagging the exhaust achieve?

[bottle]

It stops you burning yourself when it is hot.

[WotEver]

It stops you burning yourself when it is hot.

And it allows your boat to get its BSC.

 

Tony

[Marky_Mark]

does it help to warm the Exhaust ?

[WotEver]

does it help to warm the Exhaust ?

Yes, but I've never worked out an easy way...

[magpie patrick]

Its time to fit some exhaust lagging to my engines exhaust. Now I'm sitting at home and want to go and get some lagging tomorrow so I can fit it at the weekend. I am sure the sensible thing to do is wait till the weekend, measure it, and buy some next week. But... I'm not really like that 'cos I'll still get it wrong. So how much have you used? My 2"1/2 or 3" pipe comes out of the engine along a bit round a bit then goes up. Enters the silencer 5"diameter (ish) for a couple of feet then goes back to a pipe for six or so inches then out the roof. I have not uses a tape measure on this, can you tell?

 

I have done a search on the forum and know the perils of diesel soaked lagging or securing it with cable ties but so far no help with length.

 

Any help, to the nearest meter or mile, would help.

 

Regards

 

Wrinkley

 

The way that 3 feet of the stuff disappeared when I had a 6 inch gap in my lagging suggests you need an awful lot. Trouble is procuring it.

 

Motor dealers don't sell it unless they work with racing cars, boatyards tend to only stock enough for their own purposes, dealers sell it by the 200 foot roll (although that would make sure you had enough )

 

Having got exasperated over trying to get some, we got ours by chance. Going to get Juno and take the keys, she wasn't ready, the boatyard guy had broken a finger and been unable to complete our anti-foul. Apropos nothing I asked if he had exhaust lagging, explaining the other boat needed some. Because the boatyard where we bought Juno runs a hire fleet he had yards of the stuff, and cut of a two metre length "to make sure" and gave it to me, he also gave me wire ties to secure it. He wouldn't take payment.

 

imagine how much you might need, double it, double it again, and perhaps multiply by three just to be sure...

[Wrinkley]

Getting worried now. Worried enough not to get some until I measure the pipe and silencer. If I measure the circumference of the pipe to find out how much to wrap round once, divided the length by the wide of the wrap to find out how much to cover it. Add 50% for the overlap and two bends and do the same for the silencer that should do it. Just thought how do you cover the end of the silencer. I think I need a nurse to apply this?

[RLWP]

Getting worried now. Worried enough not to get some until I measure the pipe and silencer. If I measure the circumference of the pipe to find out how much to wrap round once, divided the length by the wide of the wrap to find out how much to cover it. Add 50% for the overlap and two bends and do the same for the silencer that should do it. Just thought how do you cover the end of the silencer. I think I need a nurse to apply this?

 

In my opinion, rather than add 50% I'd double the length. That way you can be sure you have enough, and get a proper overlap on the wrappings

 

I did a short bit on Tawny owl, and that bandage doesn't go very far

 

Richard

[alan_fincher]

In my opinion, rather than add 50% I'd double the length. That way you can be sure you have enough, and get a proper overlap on the wrappings

 

I did a short bit on Tawny owl, and that bandage doesn't go very far

 

Richard

I endorse that.

 

I'd say each wrap needs to 50% overlap the last, so that there is effectively a double thickness all over. That means you need to calculate how much would cover the pipe and box about twice, if it were just butted together side by side on each turn.

 

I'd not buy less than that - perhaps even still add a bit for safety......

[Marky_Mark]

Search ' Exhaust Lagging ' on Ebay, some good deals on there, Also Click me ,....

[RLWP]

£1.42 is a good price

 

Another thing, because it's tucked away under the deck, our silencer isn't lagged and passed the BSC that way

 

That could save some money

 

Richard

[Québec]

according to Acorn Chandlery

 

A 5m length will cover about 1m of 40mm pipe, when wrapped with a 25mm overlap.

 

Selling it here: Clicky

[RLWP]

according to Acorn Chandlery

 

A 5m length will cover about 1m of 40mm pipe, when wrapped with a 25mm overlap.

 

Selling it here: Clicky

 

Ad they sell copper wire to fix it too!

 

I stripped mine out of some twin and earth solid mains cable

 

Richard

[jelunga]

Getting worried now. Worried enough not to get some until I measure the pipe and silencer. If I measure the circumference of the pipe to find out how much to wrap round once, divided the length by the wide of the wrap to find out how much to cover it. Add 50% for the overlap and two bends and do the same for the silencer that should do it. Just thought how do you cover the end of the silencer. I think I need a nurse to apply this?

 

 

OK ,shall we do this scientifically.

 

Here is a formula, allowing for 50% overlap

 

PiDx1.5L = length of lagging in inches

where D = outside diameter of exhaust

L= length of exhaust to be lagged

w=width of lagging

 

all dimensions in inches

50% overlap allowed.

 

Am I right? Or is this bollocks?

 

 

So for a 12 inch lenght of pipe of diameter 3 inches using 2 inch width lagging, you will need 170 inch length of lagging.

 

???

Keith

[RLWP]

OK ,shall we do this scientifically.

 

Here is a formula, allowing for 50% overlap

 

PiDx1.5L = length of lagging in inches

where D = outside diameter of exhaust

L= length of exhaust to be lagged

w=width of lagging

 

all dimensions in inches

50% overlap allowed.

 

Am I right? Or is this bollocks?

 

 

So for a 12 inch lenght of pipe of diameter 3 inches using 2 inch width lagging, you will need 170 inch length of lagging.

 

???

Keith

 

Let's see. Pi is about three, so circumference is about 9". Length is 12", so that's 6 strips 2" wide, double it for 50% overlap is 12 strips. 12 times 9" is 108" so buy 110" or 2.75 metres. Three metres 'cos it's sold by the metre

 

Richard

Edited October 7, 2010 by RLWP

[Wrinkley]

14 times the length of 3" pipe? So for 2 meters of pipe 28 meters of lagging? My that is a lot of stuff. We're getting near Marky Marks 100 meters. How much are those shinny lorry silencer covers? Could be a lot simpler.

[RLWP]

14 times the length of 3" pipe? So for 2 meters of pipe 28 meters of lagging? My that is a lot of stuff. We're getting near Marky Marks 100 meters. How much are those shinny lorry silencer covers? Could be a lot simpler.

 

How would you bend it around the flexible pipe?

 

Richard