I am working on another custom exhaust and I have the following measurements. The header terminates in a male tube 1.66-1.69" OD depending on where you measure it. I found 1.75" SS exhaust tubing 16g would be 1.75-(0.065*2) or 1.62" ID 1.75" 18g (0.049" wall) would be 1.652" theoretically. http://www.mandrel-bends.com/catalo...18-gauge-304-stainless-straight-tube-390.html I know I am going to need to massage this tubing slightly to make that joint a nice slip fit. I've read some reviews of exhaust pipe expanders on Amazon etc and did not get a good feeling but I am only trying to get a little bit of diameter out of this tubing. http://www.amazon.com/Lisle-32500-Exhaust-Pipe-Expander/dp/B0002STSNU Suggestions including buying new tools or having a shop do it?
I've built a couple exhaust collectors for LC8's and needed to get some SS pipe expanded. I went to a local guy that does custom exhausts and headers to have the pieces expanded. As soon as he saw the SS he said it will split. Sure enough,,,,every piece he tried to expand split. Some split as soon as he put pressure on them and others split after about 1/16"
I have to think it's possible in some way. The guys mandrel bending this stuff are deforming the metal much more than I would be getting fifty thousandths or so. But I guess I would be getting close to the 1/16" you were. I have some larger diameter SS from this same supplier and I might try out a piece with a local muffler place before buying a bunch of new stuff. Everything from this joint back to the can will be welded so I really only need it fit this one section. Hell even if it split I could pretend it was supposed to be that way in order to split it for clamping. I could also slit the tube and form it over a blank I make on the lathe and TIG weld it but I think that's a lot of effort for something that should be easier. What wall thickness was the material you had when it split?
This is my pipe expander - you need to heat the pipe for it to expand. Exhaust shops have hydraulic expanders that work pretty well....but not pretty.
18ga SS. Maybe with the little bit you need to expand it will be fine. The shop I use has been doing this work for as long as I can remember,,, he can bend anything. He's even bent a couple brass and copper boat exhausts for me over the years. We did try heating one and it split just as easy. Not sure what you mean by not pretty,,, the hydraulic expanders are the same principle as the manual.
Don't know if you could go the other way with a bigger tube but Concours has some 2" stainless .060 wall for sale In the FM and the price seems pretty reasonable to me.
Hi, Pete ,your local exhaust guy can shrink tubing also on a good exhaust machine. Regards,Ed also HF has a small 1.125 to 2" ? expander
Did you anneal the tubing or heat it up and try expanding it while red hot. I'm just curious because I have my first exhaust project comming up and I will be using stainless tubing. Id love to see some pics from the Op as the project progresses, will you also be fabing up a muffler?
This was one of the multiple failures.... Not saying it can't be done but we tried without any luck. We did try anealing and were met with the same exact result. As soon as the expander exerted pressure the tube split. In the end I used plain steel header tubing. The rest of the system was plain steel so I really didn't worry about it.
I use one of those manual pipe expanders to make squished pipes round again, I've never had any luck expanding one enough for a slip fit, it ends up not quite round.
I'll be posting pics in my build thread in the some assembly required forum. I built a header from scratch last time for a CBR600, wow that was an exercise in humility. I did it out of carbon steel as I also have a tubing bender for some of the shallow bends and the guy I bought the tight radius bends from said it would work better than stainless. For this project, I am using the stock Ninja header, and coming from the much discussed swage back under the motor and up the side of the subframe like all the other exhausts you see. I'll be doing it out of stainless and then using a carbon fiber Scorpion can I bought off ebay yesterday for $50. I like the carbon cans because they are really light and don't get hot like stainless. The only crap part about building it out of stainless is back purging the tube with argon the whole time you are welding it. But it's a fairly simple task once you have done a couple. This will be my third exhaust and hopefully I don't make any mistakes. Even if the tube cracked like the pics above, I'd be fine with it as I would just weld it back up
<!--[if gte mso 9]><xml> <w:WordDocument> <w:View>Normal</w:View> <w:Zoom>0</w:Zoom> <w:TrackMoves/> <w:TrackFormatting/> <wunctuationKerning/> <w:ValidateAgainstSchemas/> <w:SaveIfXMLInvalid>false</w:SaveIfXMLInvalid> <w:IgnoreMixedContent>false</w:IgnoreMixedContent> <w:AlwaysShowPlaceholderText>false</w:AlwaysShowPlaceholderText> <woNotPromoteQF/> <w:LidThemeOther>EN-US</w:LidThemeOther> <w:LidThemeAsian>X-NONE</w:LidThemeAsian> <w:LidThemeComplexScript>X-NONE</w:LidThemeComplexScript> <w:Compatibility> <w:BreakWrappedTables/> <w:SnapToGridInCell/> <w:WrapTextWithPunct/> <w:UseAsianBreakRules/> <wontGrowAutofit/> <w:SplitPgBreakAndParaMark/> <wontVertAlignCellWithSp/> <wontBreakConstrainedForcedTables/> <wontVertAlignInTxbx/> <w:Word11KerningPairs/> <w:CachedColBalance/> </w:Compatibility> <w:BrowserLevel>MicrosoftInternetExplorer4</w:BrowserLevel> <m:mathPr> <m:mathFont m:val="Cambria Math"/> <m:brkBin m:val="before"/> <m:brkBinSub m:val="--"/> <m:smallFrac m:val="off"/> <m:dispDef/> <m:lMargin m:val="0"/> <m:rMargin m:val="0"/> <m:defJc m:val="centerGroup"/> <m:wrapIndent m:val="1440"/> <m:intLim m:val="subSup"/> <m:naryLim m:val="undOvr"/> </m:mathPr></w:WordDocument> </xml><![endif]--> You can take one of the cheap expanders and cinch it up tight. Then you take a small hammer and peen evenly over the outside of the pipe. If it works for you like it did for me the expander will be loose. Tighten to round pipe, then remove, check fit and repeat as needed.. <!--[if gte mso 9]><xml> <w:LatentStyles DefLockedState="false" DefUnhideWhenUsed="true" DefSemiHidden="true" DefQFormat="false" DefPriority="99" LatentStyleCount="267"> <w:LsdException Locked="false" Priority="0" SemiHidden="false" UnhideWhenUsed="false" QFormat="true" Name="Normal"/> <w:LsdException Locked="false" Priority="9" SemiHidden="false" UnhideWhenUsed="false" QFormat="true" Name="heading 1"/> <w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 2"/> <w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 3"/> <w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 4"/> <w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 5"/> <w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 6"/> <w:LsdException Locked="false" Priority="9" QFormat="true" Name="heading 7"/> <w:LsdException Locked="false" Priority="9" 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I don't use it to expand one size up, but when using bending tube it doesn't make slip joints like ordinary exhaust tube, bending tube is slightly thicker. I just expand enough to make a slip joint.
I built a SS exhaust for my hot rod using 2"x 16ga 316 tubing. All slip joints were done by hand without heat. No splits. It wasn't the easiest thing to do but it did work.
Don't you think it could be easier to go oversize a little? You are welding anyway. I have some SS tubing here, specs are 1.9" OD and 1.75" ID. Sturdy.....0.066-7" wall thickness. At least I can tell you where to look if interested, my friend does metal recycling. I only picked up a short piece from him but he told me: railings from some school aquatic center.
I need to either purchase prebent sections or do them myself. Since large radius dies are very expensive for my bender and the mandrel bends are cheap relatively, I'm going with such sizes I can buy. Plus if I was going to buy another die 1.75" is an easy one to get rid of sure to popularity of the off road crowd.