How to make a brake line straightening jig

I was about to start work on the brake lines on my 56 Chevy truck and decided to go all stainless lines for no other reason that I like stainless. I already had a nice jigs floating tool but no easy to straiten the coil. And let me tell you, stainless is nice and stiff. I looked online for a jig but all the nice ones were in the $200 range. That is not unreasonable if it is a tool that you will use more than once or twice a year or five. In my case that was likely going to be used a few times but not $200 worth of times.

As the jig is fairly basic in concept and construction the only issue would be sourcing the parts. Luckily we live in a world where you can pretty much buy everything from Amazon, eBay and McMaster-Carr.

I found some wheels for a decent price with the proper channel geometry on Amazon. I initially designed the jig with the idea that it would be able to do 3/8 and smaller diameter tubing.

Deciding on the design

I explored a few approaches but most of them required springs or an extra compression mechanism. The obvious solution for me was to use something that I already had and after looking around the garage I realized that a vise is the perfect clamping mechanism with it’s built in adjustment. The only limitation this has is lack of portability, but if you are working with stainless like I was any handheld device would be a pain in the trunk, unless it has some kind of crank or mechanical assist.

So long story, longer I decided to make some custom jaws and use the vise as the tension mechanism. This allows me to use it on any diameter under 3/8″ with just a few quick turns of the handle.