• Magnetic Jigs

Jig for Soldering Brass Bars

My Jig Setup

I’ve had numerous inquiries as to my setup for soldering.  I’ve tried multiple different variations, but have found that without a doubt the best way to solder a tube chassis is with a magnetic jig.

There is some initial investment involved here, but once you have your setup it will last for many years, and is as versatile as your imagination.

There are really only 3 or 4 elements that you’ll need for an adjustable jig that is perfect for soldering.

To start, you’ll need a good steel plate, something large enough to work on, but small enough so you can store it away when you’re not using it. You have to use steel so your magnets will stick to it.  You don’t want to use some old plate either.  You want to use a plate with a good smooth surface so all of your bars will sit flush.

This one would be perfect to use, and will run you about $10 with shipping:


Steelworks Boltmaster 24X12 22Ga Stl Sheet 11775 Sheet Steel

The next and most important item for your jig is the magnets.  Dime store magnets will not work.  You need serious magnets will enough force to hold everything in place.

Neodymium Block Magnet

Neodymium Magnet

Rare Earth (Neodymium) magnets are some of the strongest magnets you can buy, and if you haven’t ever played with some, you will be shocked at how true that is.  Use of these magnets is crucial to the success of your jig.

I recommend using block magnets over round magnets because you can stack them, or lay them on their side for more possibilities.  I use 1/2″ x 1/2″ x 1/8″ magnets because of their pull force.

When i first purchased mine, i searched around and found that K&J Magnetics was the best place to buy, they had a good selection and ordering was easy.  (don’t order yourself any computer components or anything the same day, if they arrive together, the computer circuitry will probably be toast.. these magnets are strong!)

Next you’ll want to get some Angle Bar. I chose aluminum because it’s relatively rigid, easy to cut, and isn’t affected by magnetism. I recommend using the thinner 1/8″ version over 1/4″, because the closer the magnets can get to your steel plate, the stronger they will hold.


Aluminum 6063-T5 Angle ASTM-B221, 1/8″ Thickness, 1/2″ x 1/2″ Leg Length, 72″ Length

I used a band saw to cut my angle bar to various lengths, 1″, 2″, and 3″.  The angle bar is used for clamping, for holding a part true to a line on your plans, or for elevating a part up off your soldering table.

Speaking of clamps, you’ll want a good supply of mini spring clamps. Use the metal ones, not plastic (they will melt!).  In the example jig photo at the start of this article, i’ve remove the clamps for photography, but i do use them extensively to hold the bars flush against the aluminum angle bars to keep everything perfectly straight before soldering.


12 Spring Clamps Woodworking Craft Hobby Repair Tool 2″

The Dirt Late Model plans are designed to be printed out.  The plans for the sub-assembly you wish solder is set onto the steel plate.  Using the magnets, angles, and clamps you  box in the parts so everything is aligned and held fast.  Once the parts are perfectly in place,  apply some flux with an acid brush, and solder using a torch.  The paper will scorch during this operation, but after 10 years i’ve never had a fire.  (I highly recommend having a fire extinguisher nearby)

Smaller parts can be laid out on the plate using only the magnets.  They hold strong enough that you can solder multiple parts and they will stay put as you pull out the finished part, and set the new parts in place.

Leave a Reply