John Minchell Posted February 19, 2023 Share Posted February 19, 2023 Anyone got a clever way to remove dents from tuned pipes when you can't get to the inside with a tool? And the pipes are the expensive Krumscheid tuned expansion chambers so I don't want to start cutting them open as my aluminium welding is well out of practice? TIA John M Quote Link to comment Share on other sites More sharing options...
Engine Doctor Posted February 19, 2023 Share Posted February 19, 2023 The pipe part should be easy if you can get a rod along to the dent. The canister is a bit of a problem though . The dent shouldn't affect its performance though just looks ugly . My only suggestion would be to drill a hole to pull or push the dent out then fill the hole with low temp Ali brazing rod the grind down the filling and polish . You can anneal the earea first by heating with a smear of soap on the area and when it turns black plunge it into cold water. This will soften the ally and make it easier to reshape. Quote Link to comment Share on other sites More sharing options...
Don Fry Posted February 19, 2023 Share Posted February 19, 2023 Crude fix, Engine Doctor reckons it will still work. Leave alone, fill the dent. But I feel the pain, been there. Game of blood. Quote Link to comment Share on other sites More sharing options...
john stones 1 - Moderator Posted February 19, 2023 Share Posted February 19, 2023 I would leave it alone, the header part looks like it'll fracture if you set about it. Quote Link to comment Share on other sites More sharing options...
GrumpyGnome Posted February 19, 2023 Share Posted February 19, 2023 Just leave it. Won't make much difference.... ignore the aesthetics Quote Link to comment Share on other sites More sharing options...
John Minchell Posted February 21, 2023 Author Share Posted February 21, 2023 Thanks for the replies chaps. John M Quote Link to comment Share on other sites More sharing options...
Jon H Posted February 21, 2023 Share Posted February 21, 2023 Fill it with water and freeze it? it might completely explode though 1 Quote Link to comment Share on other sites More sharing options...
Mike T Posted February 22, 2023 Share Posted February 22, 2023 You may be able to raise that 'crease' a little by annealing then tapping gently (many, many taps) on either side with a planishing hammer. You wont get it out completely without a mandrel of some sort. How big is the aperture at the engine end? Quote Link to comment Share on other sites More sharing options...
John Minchell Posted February 22, 2023 Author Share Posted February 22, 2023 Mike, the crease is 165 mm along the taper from the open (inlet) end and dia from the exhaust header is 21mm. The dent at the exit end of the pipe is 46mm in from the rear end and its only 14mm dia. So can't get a curved mandrel in big enough or strong enough to do the job. Quote Link to comment Share on other sites More sharing options...
Mike T Posted February 22, 2023 Share Posted February 22, 2023 (edited) OK - assuming the pipe is straight and with no baffles up to the point of the crease, then you only need a mandrel with a reach of, say, 180mm. A 300mm length of 15mm dia steel rod with the end rounded to a hemisphere and mounted in a bench vice should give you enough overhang to get at the crease. I'd try working the pipe over the mandrel by hand to start with and if it proves too stiff, then resort to the hammer. If the pipe is baffled, then you've got no means of working the outlet dent, other than major surgery. Rotate the pipe so it's facing the airframe 😉 Edited February 22, 2023 by Mike T missing dims. Quote Link to comment Share on other sites More sharing options...
John Minchell Posted February 22, 2023 Author Share Posted February 22, 2023 Ah never thought of gripping the bar in a vice and working the pipe in my hands. Will try it at the weekend. Thanks Mike. Quote Link to comment Share on other sites More sharing options...
Bruce Collinson Posted February 22, 2023 Share Posted February 22, 2023 If I had to do that, I’d try to get the local Dentmaster bloke to look at it as I understand they carry mandrels of all shapes and sizes. BTC Quote Link to comment Share on other sites More sharing options...
Recommended Posts
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.
Note: Your post will require moderator approval before it will be visible.