Bending Fuel Lines

[jswareiv]

Looking for some advice and techniques for bending the aluminum fuel lines. I have a tool, but it will only radius so far because of the fixed bend in the tool. I didn't want to bend it by hand and risk crimping it. There must be a better way.



Here is the tool I am using.

[N427EF]

You'll get lots of advice on bending fuel lines.
Referring to your picture, you simply shorten the straight end a bit and open up the radius a tad and your tube will fit.
I always leave the straight end for last so you can custom size the tube.
Don't be afraid to bend the tube between your fingers, gentle bends only.
I found that not using a bending tool except for the clean 90 or 180 degree curves works much better without a tool.
Even the finest bending tools collapse the tube just a little bit and generally leave a few marks on the tube. Gently persuading a fuel line between your fingers for a perfect fit is far easier and more accurate than trying to use a bending tool for every turn of the fuel line.
Needless to say, you can't bend as tight by hand and no matter what, you cannot collapse the fuel line.

[BillL]

You have the best tool there. I have had some luck using the tool, lessening the bend angle, then using a wooden buck of the correct radius to tighten the radius.

I am not adept at hand bends as in the end they just don't look so neat. I made a tube straightener and make sure the tube is long and perfectly straight before beginning. It only took about an hour to make.

Happy bending.

Oh -I have the parker roloflare (and I am very happy with it for aluminum), but recently had the opportunity to use the, very heavy duty, Ridgid 45 deg flare tool on some 3/4 copper. It is fantastic!!. All steel, nice off set roller and makes beautiful flares. Nice surface finishes too.

[terrye]

Sorry, you do NOT have the best tool there. I have one of those in my toolbox, and after some frustrating bends like yours, bought a 1/4" and a 3/8" RIDGID series 400 instrument tube bender. Even though I hated to spend that much extra money, they are much better tools.
https://www.ridgid.com/ca/en/400-ser...rument-benders
Measure the bend radius on the drawing and measure your tube bender. I think you'll find your tube bender has a larger radius. Also check the bend radius on the RIDGID benders.

[rvbuilder2002]

The line shapes were based on a bend radius of 1".

The prototypes where made using an economy tube bending tool similar to THIS

[BillL]

Originally Posted by terrye

Sorry, you do NOT have the best tool there. I have one of those in my toolbox, and after some frustrating bends like yours, bought a 1/4" and a 3/8" RIDGID series 400 instrument tube bender. Even though I hated to spend that much extra money, they are much better tools.
https://www.ridgid.com/ca/en/400-ser...rument-benders
Measure the bend radius on the drawing and measure your tube bender. I think you'll find your tube bender has a larger radius. Also check the bend radius on the RIDGID benders.

You certainly have a better tool, but I did measure the bend radius on the Imperial shown by the OP and specifications for the Ridgid, and they are both the same, at least for the 3/8" tubing. If one has the need to bend stainless or harder materials, the Imperial would not suffice. The mandrel surfaces are painted and would not be as durable with repeated stainless usage. I think for 3003 aluminum the Imperial will produce a good quality bend, but it is more bulky than a dedicated 3/8" tool.

[TS Flightlines]

There are alot of different benders out there, and most will bend a similar radius. Personally, I have several Imperial 364-FHA benders that in some cases I modified to do some specialized things. ( UH----Steve is working on the CNC bender now.)
Take your time, dont try and bend something too tight, or with insufficient wall thickness. The tubing as supplied by Vans will bend just fine.

Tom

[gasman]

This tubing bender.... http://www.harborfreight.com/tubing-bender-3755.html ... for under $7 will work just fine if you file some edges and place shipping tape over some of the dragging surfaces. I would match the quality of bends to any bender.

Do a sample and see what needs to be cleaned up. You don't want any marks on the tubing.... trim and do another. Results will be a cheap and useful bender.

You do need to plan ahead when bending tubing. When you can, allow for extra to be trimmed off of each end. And make your flairs last. Take a piece of tubing and mark it in the center for 2" at 1/16 per mark. Then start your bend at the first mark and make a 90* bend. At the end of the bend, make a finish mark. You now know how much tubing is needed to make the bend.Leave an inch straight on each end. Do the same with a 45*.

Make up a couple flared ends with an inch of flat. Get some clear tubing that fits over the aluminum tubing and cut to represent straight runs and install the bends and ends as needed. Now, just measure between the lines and to the ends of the flair. Do not add anything for the flair, it consumes almost no length. Add up the 1/16" marks in each bend and you have the length needed to make your tubing run.

[RV7A Flyer]

Best I've used so far (wish I owned a set of these, but fortunately, a friend has access to them ):



Swagelok. Pricey. Excellent.

[JRichichi]

I've got the Ridgid series 400 tube benders. They aren't cheap but they work great. I've only used them on 3003-0 and 5052-0 aluminum tubing however. I found a drop of oil on the "shoe" helps with getting a nice surface finish on the tube. I also modified the tool using the same method that Tom Swearengen talks about in another thread. His modification of the bending tool (and mandrel for holding the tubing with the latch) allows me to start the tangent of the bend right up against the end of the AN819 sleeve. Great idea there Tom!!!

I'll post some pix of the tubing bends when I get to a computer that has the pix on it.

I hope this helps.

Jeff