getting out dents

[mrbb]

OK I have seen a few video's about getting dents out of a pipe
and was wondering how many people have every done thsi them self, and how ell it worked

I am talking about plugging the pipe,and filling it with air and then heating it with torch

I have a FMF Gnarly pipe off a 2000 YZ 250 that has a few dents in it, I know its a pretty heavy gauge pipe, has any one done this on this type of pipe, and ???

thanks for any imput you feel might help

 

[Bonehead]

Mrbb I have done lots of pipes over the years and have come up with a variety of plugs and fillers. The one thing I will tell you is safety wire the plugs in better than you think and never stand in the way of a plug! Go slow with the heat and consintrate on the dent or you will over fix the dented area.

 

[mrbb]

Thanks

I have read a bunch on this subject, seems a lot of folks have a lot of worries, concerns on a pipe over expanding and or blowing up/fires

should I try to clean the insides first?? maybe flush them out with a cleaner, then rinse the out real well with water and let dry??

what do you recommend I try for caps? and yes I planned to wire them good, extra good from what all I read, and go slow

if I had a pipe shop or place that did near me would just drop off, but none near where I am at
Northeast PA, so, figured I would try this trick, as in all the video's I saw seems pretty simple, minus the worries about a weak weld fire blowout I guess!

any recommendation on how much air pressure, and or what is TOO much pressure to not go up to??

thanks again

 

[pesky nz]

+1

The one thing I will tell you is safety wire the plugs in better than you think and never stand in the way of a plug!

I have used a rubber door stop with an 8mm bolt and washers to squash and block the tail pipe end successfully my one is about 25mm thick. It needs to be clean where the rubber touches the pipe. I have tried similar front pipe bungs with three bolts but they were not trustworthy and popped out at close to leathal force too often so on the header end I use a large washer and solder it in place with easyflow or silphoss and use an old valve from an innertube in the centre to be able to fill with compressed air. Whwn I'm finished I heat the solder joint and remove it then pollish the area free of solder. BIG WARNING YOU ARE MAKING A POTENTIAL COMPRESSED AIR BOMB if you count the number of square inches on the surface of the entyre expansion chamber and multiply it by the psi that is how many pounds of energy can be released. Wear safety glasses or a complete head shield. My experiences needed around 60 to 80 psi and heating to a just visible cheery red, any sparkling is way too hot and will usually end with a blow hole shooting sparks across the workshop. I usually had to add extra air after each dent as the pipe got bigger inside more than the heat over-pressurised. If any area bulged out too much a very gentle tapping with a small hammer will be able to smooth it back into place. I've never had an explosive split but often get a leek and have to depressurise and weld up small cracks or pin holes.

 

[Bonehead]

That is absolutely coerect Pesky I like the soldering a cap on. I may try that on the next one. I have shot plugs out that have stuckt into the ceiling

 

[mrbb]

thanks guys, I was thinking about sodering an end as well

I also planed to wrap the ends with wire mess, and also wire the ends on, so if any came off they could be caught or at least slowed down a lot!

I have some heavy duty leather I was going to some what wrap the pipe with as well so if any thing lets loose, it too would be slowed down or caught!


read a lot lately on pro's and con's

most say they get by with about 35 psi too, so will start at about 20-25 and work up as things go


thanks for the idea's and imput

maybe next week I will give it a try if i have the time!

My next question is, besides looks,
How many actually feel any power come back afterwards??

and has anyone had any problems with pipes rusting where they were heated, and or does anyone think they re dent a lot easier after a fix like this??