# Pipe Bender Jig



## Chris Scott (Jan 2, 2008)

In another thread a pipe bender had the potential of being the solution to a pipe fitting problem; although not suggested. I'm posting this pipe bender jig idea separterly so it; 1. may inspire or help; 2. hopefully will become reference, not get lost and could be found if or when someone might search for Pipe Bender info - no matter how remote that may be.









This design is credited to Torry Krutzke who showed it to me several years ago. I have not seen or read about similar pipe bender before or since. 



This jig can be used on rough pipe (no fittings on ends), or finished pipe. Finished pipe here means fittings on one or both ends which prevents using a bender where the pipe must be inserted into the bender, i.e. coiled wire type, etc. 

This example jig is made from hardwood. If you can cut it from brass (as pictured below), or AL, etc., that's even better. Hardwood is appropriate for those of us who are machining challenged.
Pipe Bender Jig: 
- This example is for 3mm Accucraft copper pipe. 
(Measurements are approximate as this mixes English and Metric measurements. If larger/smaller, English/Metric adjust the sizes and measurements to suit.) 


- "Bend" means the diameter as measured on the inside bend of the pipe.


- Begin with a short length of hardwood dowel. HD or hardware store is usually maple, but it must be a hardwood. 


- Dowel should be ~1/4" larger in diameter than the bend diameter, i.e., a ~3/4" dia. bend = a ~1" dia. dowel.


- Cut a grove, dado, 3mm+ wide and 3mm+ deep (~


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## HMeinhold (Jan 2, 2008)

Chris, 
What is your trick? I made several of these benders with groove depths between 1/2 to 1/1 of the tubing diameter and precise fitting width. Even with annealed tubing I never got nice bends without affecting the cross section. The tubes flattened at the bottom and thentop. The only benders which work well for me are: 
http://www.hobbylinc.com/htm/dub/dub785.htm 
Regards


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## Chris Scott (Jan 2, 2008)

Posted By HMeinhold on 09 Jun 2010 09:54 PM 
Chris, 
What is your *trick?* I made several of these benders with groove depths between 1/2 to 1/1 of the tubing diameter and precise fitting width. Even with annealed tubing I never got nice bends without affecting the cross section. The tubes flattened at the bottom and thentop. The only benders which work well for me are: 
http://www.hobbylinc.com/htm/dub/dub785.htm 
Regards 


Finese, patience, love? Heck if I know.









Flatening bottom/top? Bend radius too tight for the pipe diameter; the pipe wall is too thick, bending pipe too fast??? Things that come to mind. Maybe try a pipe that flattened (top or bottom) and try bending it to 2x-3x the radius. If that works, the problem bend was too tight for that particualr pipe?

I tried the DuBro (your linked), limited to 2, maybe 3 English pipe sizes. K&S wrapped wire benders are another option. They too are limited to just 4 English sizes. Metric sizes are a problem with these. 

Heard of two other methods - never tried either; 
1. a soilid wire tight fit through the pipe. Have to find the wire; seems like small OD pipes with this would not work.
2. heat pipe and fill with solder, bend pipe, reheat to drain the solder. I may not have the exact details of this right (?). Maybe someone can fill in the right details.


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## hawkeye2 (Jan 6, 2008)

Cerrosafe and Cerrobend are 2 alloys of Wood's metal that melt at about 158 F and are used to fill pipes for bends or to make castings of something that you need to measure such as the chamber in a firearm where you can't measure it directly. The metal can be removed from the tube by immersing it in hot water till it melts out. The metals are expensive but can be reused and a pound is a lifetime supply. Here is a link to a how-to for bending tubing:

http://www.canadametal.com/pdf/cerro_bending.pdf


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## rbednarik (Jan 2, 2008)

One can also fill the pipe with water and freeze it, or fill with compacted sand to eliminate the risks of kinking while bending. The pipe should always be annealed first. 
I wouldn't want try the solder method since you can never guarantee the pipe to be completely clean after blowing out the solder. You wouldn't want little pieces of solder going into your water system or worse. Cerrosafe is another nice compound to work with for tube bending. 


The K&S benders are great for any angle under 45*...good luck getting the spring off of a 90* bend as the tube still deforms somewhat. I have a few tubes in the shop that attest to that with an unintentional cooling coil (pipe bender) built in! 

Personally, either using annealed pipe and bending by hand (for 1/16", 2mm and 3/32") or with the DU-bro pipe bender (1/8" or 3mm) works well. I also have modified a set of automotive brake line pliers that can accept 5/32-1/8" pipe, which is useful for superheater tubing.


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## xo18thfa (Jan 2, 2008)

Posted By rbednarik on 10 Jun 2010 07:18 AM 
One can also fill the pipe with water and freeze it, or fill with compacted sand to eliminate the risks of kinking while bending. The pipe should always be annealed first. 
I wouldn't want try the solder method since you can never guarantee the pipe to be completely clean after blowing out the solder. You wouldn't want little pieces of solder going into your water system or worse. Cerrosafe is another nice compound to work with for tube bending. 


The K&S benders are great for any angle under 45*...good luck getting the spring off of a 90* bend as the tube still deforms somewhat. I have a few tubes in the shop that attest to that with an unintentional cooling coil (pipe bender) built in! 

Personally, either using annealed pipe and bending by hand (for 1/16", 2mm and 3/32") or with the DU-bro pipe bender (1/8" or 3mm) works well. I also have modified a set of automotive brake line pliers that can accept 5/32-1/8" pipe, which is useful for superheater tubing. 

Freezing water... That's sounds like an experiment. I've used super fine dry sand. That works down to about 5/32" Anything smaller it does not work. I have some plans for rather elaborate benders, but they look like more of an exercise in building the machine rather then bending the tube. I made a bender based on Colin Binnie's plan. It works OK, but is a real pain in the neck to set-up.

Here's his plan










Here's my bender










I have a set of plans for this bender. Looks like it would be easier to use but a tougher to make.


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## Brooks (Jan 2, 2008)

When using Torry's jig, a step that may be crucial (and was listed in his original post describing his jig) is to support the pipe on the table as you roll the jig over the pipe. The pipe is trapped between table and the jig slot. I never bend the pipe in the jig while holding all parts in the air; all parts of the bending pipe must be supported, either by the floor and walls of the jig (100% depth groove), or by the table top. Annealing first is also crucial. I've only bent thin-wall 1/8" K&S pipe, so can't comment on other sizes.


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## Dwight Ennis (Jan 2, 2008)

I made a bender based on Colin Binnie's plan. It works OK, but is a real pain in the neck to set-up.This is very similar to Du-Bro's benders Henner mentioned above Bob. I have both Du-Bro benders (1/8 & 5/32). For under $10.00 each average, they can't be beat!! Both work perfectly, will bend tubing past 90*, and for the price, are far easier than making something.


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## xo18thfa (Jan 2, 2008)

Posted By Dwight Ennis on 11 Jun 2010 08:28 PM 
I made a bender based on Colin Binnie's plan. It works OK, but is a real pain in the neck to set-up.This is very similar to Du-Bro's benders Henner mentioned above Bob. I have both Du-Bro benders (1/8 & 5/32). For under $10.00 each average, they can't be beat!! Both work perfectly, will bend tubing past 90*, and for the price, are far easier than making something.









Looking at the DuBro bender, I think it's a better design. Mr Binnie's design requires a lot of fiddling to get the rollers and spacers tightened. If they are not tight then they slide apart in the middle of the bend. The DuBro looks it does a good job of preventing the tube from slipping, which is the problem with Binnie's if it's not tight.

Being the son of mid-western farmers, it is in the genetics to build everything. I just need to stick a crow bar in the wallet and get DuBro's.

Bob


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## Dwight Ennis (Jan 2, 2008)

I just need to stick a crow bar in the wallet and get DuBro's.It doesn't take a huge crowbar for $8.00 and $11.00.


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## xo18thfa (Jan 2, 2008)

Posted By Dwight Ennis on 11 Jun 2010 11:12 PM 
I just need to stick a crow bar in the wallet and get DuBro's.It doesn't take a huge crowbar for $8.00 and $11.00.









I know, I know







I need to do something soon. Pipes for the Nina are just around the corner.


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## Chris Scott (Jan 2, 2008)

Different Pipe Benders work in some situations and not in others. Below are examples.


Du-Bro(top) and K&S pipe benders can work well. It depends on the pipe length and with short pipe whether the short pipe already has fittings, either Ferrel & Nut or other:











If the pipe is short and already has fittings then Du-Bro and K&S pipe benders have problems, the pipe will not fit in these pipe benders:











This is where Torry's pipe bender works really well:




















Torry's makes his Pipe Benders for English sizes; 1/16", 3/32" and 1/8"; The pipe he uses for his Coal Conversions. As Brooks described Torry's bender as designed needs the pipe annealed, pipe in the slot and the bender rolled on a flat surface to make a bend. With metric pipe the fit is a little different, a little better I think. The metric ~equivalent sizes are slightly smaller, i.e., 1/8" (0.125 vs 3mm (0.1181); the result metric pipe fits lower in the grove and snug. 

Accucraft 3mm pipe is my specialty, or pretty much every pipe I need to bend or reshape to fit a tight space. The 3mm snug fit makes rolling on a table optional. I can use two hands; one holding the pipe in the slot then I can use both hands to shape the pipe bend. I have gotten so used to Torry's bender and this method with any length pipe or bend I them for pretty much every pipe. 

Hope this makes the distinction between where each of the pipe benders can be used clearer.


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## Andre Anderson (Jan 3, 2008)

A method that I used when I needed to bend tubing for my rc airplanes was to fill the inside of the tubing with mono-filament fishing line. And then bend the tubing. Harry Higley and sons ( http://www.harryhigley.com/Tools1.htm ) makes the same kind of bender as shown in the first photo and he calls it "BISO BRASS TUBING BENDERS" . His go in a vice. If I could figure out how to add a photo I would post one of his bender.

Andre


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## xo18thfa (Jan 2, 2008)

Posted By Andre Anderson on 18 Jun 2010 12:10 PM 
A method that I used when I needed to bend tubing for my rc airplanes was to fill the inside of the tubing with mono-filament fishing line. And then bend the tubing. Harry Higley and sons ( http://www.harryhigley.com/Tools1.htm ) makes the same kind of bender as shown in the first photo and he calls it "BISO BRASS TUBING BENDERS" . His go in a vice. If I could figure out how to add a photo I would post one of his bender.

Andre 



Looked at Harry's website. You could combine all the benders and drill/tap guides into a single piece of 1" or 1.25" hex bar and have a universal tool block.


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