# DIY: Exhaust tubing expander



## diive4sho (Feb 7, 2004)

I always seem to come across situations where I need an exhaust tubing expander.... you know, something like this:





Obvoiusly I'm not going to go out and spend $3,000 on a hydraulic bending machine just for the expander on the end of it. 

SO, I got the thinking.....I wonder if I can take a quality version of one of these:










and somehow use a portapower 










to ditch the center bolt and make a homemade hydraulic exhaust tubing expander?

I went to many industrial supplier websites trying to find what I would call a hydraulic pulling ram/cylinder.....only thing I found was something like this:









I couldn't see a way to make that work because the cylinder rod is far too large to fit in the center of one of those crappy handheld expander tools and the face of the cylinder near the sealing surface of the center rod is obviously not designed to take a force. This would most likely cause the cylinder to leak and fail.

Off to Harbor Freight's website to see what kind of junk they have. I find this:









Which has the type of pulling cylinder I'm looking for. The cylinder can take forces on its face without damaging the sealing surface AND the diameter of the rod is not an issue because it is flush with the face and a thin threaded rod screws into it. When pumped the rod pushes out the back of the unit. Nice!

This is how it works:






So if I order a bad ass version of an exhaust tubing spreader and one of those punch tools I should be able to combine them into some awesome franken-tool.
I did some research and found that Lisle makes the best version of a exhaust expander/spreader because their tool is designed to not only straighten an out of round pipe like the others on the market but their tool is made to stretch the pipe. So it should be up for the task. Here is the spreader from Lisle tools :








Part number 17350

Searched Ebay for the punch tool since the Harbor Freight is on backorder and they could provide no ETA on restock...

Lo and friggin behold I find this:

http://www.ebay.com/itm/10-TON-HYDR...208?pt=LH_DefaultDomain_0&hash=item2eba907618

Which appears to me to be the SAME EXACT THING that I was going to make myself only twice the price.:laugh: SAME Lisle tool combined with the SAME punch tool cylinder/ram.

I've always said that no matter what you come up with someone else has probably thought of it first. However I've never had it thrown in my face like that lol.

Longest picture story ever made short. Parts are on their way and I should have it all assembled and ready for testing by the end of next week. If all goes well (which it should because it is already an actual product being sold on the web) I will complete the DIY and you too can make your own hydraulic exhaust spreader/expander tool.


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## diive4sho (Feb 7, 2004)

I received the Lisle tool yesterday. Just waiting on the Hydraulic punch/knockout kit.


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## sdezego (Apr 23, 2004)

:thumbup:


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## ToddA1 (Apr 22, 2002)

diive4sho said:


> I received the Lisle tool yesterday. Just waiting on the Hydraulic punch/knockout kit.


Do you do that much exhaust work where this is necessary? Curious what your end cost will be after sourcing all of the parts.

I like building stuff, too but sometimes just buying an available tool is easier, lol.

-Todd


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## need_a_VR6 (May 19, 1999)

When I get rammy (often!) I just use the impact on my screw expander.


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## diive4sho (Feb 7, 2004)

ToddA1 said:


> Do you do that much exhaust work where this is necessary? Curious what your end cost will be after sourcing all of the parts.
> 
> I like building stuff, too but sometimes just buying an available tool is easier, lol.
> 
> -Todd


No but having the right tool for the job makes all the difference. I'm sure now that I have it I will find an excuse to use it often (eg, full stainless exhaust for the allroad, test pipes for friends, etc.).

$285.74 is the grand total. The available hydraulic exhaust tubing expander was close to $500 shipped. Spending almost double just didn't make sense to me.

Also, I will still have the punch/knockout tool to use whenever I need it and I can see that coming in handy. On top of that I can purchase other attachments for the hydraulic hand pump... The tubing expander is really only an attachment being created to add to the "potra-power", which is a useful tool to have in the garage. 

The knockout/punch tool is on the truck for delivery today. We will soon see how useful of a tool this will be.


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## vwangler (Jul 27, 2009)

You should be able to use that pump with a set of hydraulic dimple-dies also... I thought that SWAG off-road used to sell a kit that used that exact pump, but I can't find it now.


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## zcxerxes (Nov 13, 2005)

throw this in with it and i'd be interested.
http://www.harborfreight.com/garage-shop/hydraulic-pumps/10000-psi-air-hydraulic-pump-98318.html
just because i am lazy and impatient.


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## diive4sho (Feb 7, 2004)

Guess who else had this idea....

Snap-On

http://www.snapon.com/International/6pdffiles/cg5560hy.pdf#search='hydraulic exhaust expande

:laugh:


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## diive4sho (Feb 7, 2004)

Ok guys....It worked!

I was hoping that when I tried to put the two tools together they would have the same thread pitch and bolt size. Turns out that they were very close in size and thread pitch but one was metric and the other standard. So an order was placed with McMaster-carr for some supplies. I only ended up using the threaded rod. The nuts were a Just in case I need them item.










I took the 1 foot long rod and cut it down to 7". Unscrewed the bottom of the hydraulic ram and took the cylinder out of the center. Removed the O-Rings.
Then I welded the rod in the cylinder. Allowed it to cool down and put it all back together. Sorry I didn't take pictures of this but it is easy to understand when you have the parts in front of you.










Next I threaded the expander tool onto the rod and tested it out.






I had a piece of exhaust tubing sitting around that was swedged on the end from the factory (an autozone muffler repair pipe)

I swedged the opposite end with my tool and here is the result.
Factory on the left.............................................. .................................................. ..............My tool's swedge on the right










The fitment









an inside view of the swedged end









$285.74 Punch tool and lisle tool shipped 
$5.95 Threaded rod from McMasterCarr
$4.98 Shipping from McMasterCarr

$296.67 Total

A Hydraulic Exhaust Tubing Expander (and still functional knockout/punch tool) for under $300

:wave:


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## ToddA1 (Apr 22, 2002)

Wow, that's great and I think your swadged end looks better than the Autozone one. 

I've used the store bought ones and it looks like the expanders run parallel with the pipe and yours looks more uniform, being stretched perpendicularly.

-Todd


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## diive4sho (Feb 7, 2004)

Thanks. I'm very pleased with it. It's nice to be able to make your own joint because you can make it fit tight. I was surprised how square the inside end of the swedge was....no slop when you slide the other pipe in.

I have to admit I found the limit of the tool already. I tried to stretch a thick stainless tube and I popped the weld. Taking it apart and going to pin the bolt in and TIG it this time instead of MIG.


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## diive4sho (Feb 7, 2004)

So after I found the weak spot on the tool I ripped it down and made it stronger. 

This is the ram that is inside the punch tool....drilled a hole in it. 



















Did the same for the bottom of the McMaster Carr Threaded rod....and threaded it for an M12x1.75 bolt. 











Put the rod back in the ram. Threaded my M12x1.75 bolt into the rod through my new hole in the bottom of the ram. Welded it in place. 











Welded the top again....with the TIG this time 










Pushed the ram back into the punch tool 









Put the return spring back in 









Threaded the bottom cap back on 









All done...Time for a test. 

Remember the pipe I previously expanded? I decided to see if I could expand the part that fit inside of it, to now fit over it. That would be a very large stretch but I felt that the tool was now up for the challenge. 
Here is how it turned out. 




























This is definitely my new favorite specialty tool.


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## d-bot (Sep 6, 2004)

Hot dang, nice one!


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## 2doorV6 (Jan 29, 2003)

*sweet*

nice looking tool build definately need one


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## gbisus13 (Aug 16, 2005)

Really cool idea, but why not just use the impact gun on it? The lisle description says the expander is made to be used with an impact gun. Do you get a better stretch this way for some reason?

Also, why the 4 segment stretchers instead of the ones with more segments?


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## diive4sho (Feb 7, 2004)

If you've ever tried to use one of these tools with an impact you know how difficult it is. The bolt strips out, or the impact gun wont fit under the car in the exhaust tunnel, it wasnts to twist, it's just a PITA. A small hydraulic pump like this can put out some serious power with just a few small pumps of the lever.

The multi-sectioned expanders that you're referring to aren't meant to be expanders, they are just meant to make the pipe round again after an exhaust clamp makes it out of round.


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## gbisus13 (Aug 16, 2005)

Thank you, that makes sense. Haven't used them, the few exhausts I've done so far were just butt welded.

For these expanders, do you have to insert the entire length of the expander into the tube, or can you do just a little bit. I'm thinking of the multi-section curves I've wleded together, and if there was just a 1/2" slip joint on each curve instead of trying to fit up the butt joint on each angled cut, would make so much easier. 
I'm guessing the entire thing needs to be in the tube tho or else the 'unrestricted' end of the expander would jump out without expanding the inside the tube end? I guess could cut a scrap piece of straight section to restrict the half of the expander not in the tube needing expanded.


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## diive4sho (Feb 7, 2004)

You could do that or make a few adapter pieces and cut them down to be really short adapters.


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## diive4sho (Feb 7, 2004)

Wow, 20,000 views. Crazy


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## Lysholm (Nov 8, 2001)

agreed you should update the picture hosting...


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