Magnetic 3rd Hand

Anyone who plays arounsd with elecronics knows how important a 3rd hand is. It gives you the ability to hold solder in one hand and the soldering iron in the other and easily add solder to a component.

I've been using some homemade 3rd hands for some time and can't imagine building a circuit without one. Recently I was using a couple of magnets for a project and a resister got stuck to it. I had a bit of an epiphany and realised that adding a magnet to a 3rd hand would be a quick and easy way to hold a part whist I add solder to it.

The project is an easy one and will definitely become a welcome addition to your solder station.

Step 1: Parts and Tools

Parts:

1. PVC Cap 100mm - Hardware store. If you are in Australia then you can get these from Bunnings

2. 3 X Square washers - Hardware store, Bunnings

3. Plastic Flexible Water Oil Coolant Pipe Hose - eBay

4. Rare Earth Magnets - eBay

Tools:

1. Epoxy Glue

2. Drill

3. Superglue

Step 2: Drilling and Gluing

Steps:

1. First drill a hole into the middle of the PVC cap. The hole shjould be big enough to fit the tap section of the pipe into it.

2. Next, scratch-up the inside of the PVC cap. This will ensure that the epoxy glue sticks to the bottom of the cap

3. Add some epoxy glue to the bottom of the cap and add one of the square washers to the bottom.

4. Add more glue to the washer and glue the other 2 washers so there are 3 in total. Enure the hole is aligned to the hole in the cap

Step 3: Add the Tap Section to the Base

Steps:

1. On the tap section, there is a plastic hex nut which fits nice and tightly into the holes of the washer

2. Place the bottom of the tap into the top of the cap and with a small hammer, tap it into place

3. Make sure that the end of the tap is flush with the washer so the cap sits flat

Step 4: Adding a Magnet

Steps:

1. Add some superglue to the top of the pipe section.

2. Next, place the magnet on top of the pipe and hold down until it is stuck fast

3. I also added another magnet to the one glued to the pipe which gives you more area to attach components.

Step 5: Finishing Up

Steps:

1. Push the pipe into the tap section. If you need to reduce the size of the pipe, then just pull a few sections off which is what I did.

2. Now you are ready to use the 3rd hand. Just place whatever component againt the magnet which will hold it in place and start to solder.

Comments

[Cheesey125]

Is it rare earth magnet or neodymium

[marinusddekok]

how much does it cost?

[lonesoulsurfer]

I had most of the parts but if I had to guess I would say around $8-10.

[DIY_YID]

Interesting instructable!

[lonesoulsurfer]

cheers

[KJMagnetics]

Nice! Be careful not to overheat the magnets...they can be weakened by high temperatures!

[Gentleheart]

The demagnetisation temperature of a magnet is wayyyyyyy beyond soldering temperature (a least 3x higher). No worries there!

[killbox]

no its not, most common plated neodymium permanently loose their magnetic field at about 350C see the near the bottom under temperature effects. https://en.wikipedia.org/w/index.php?title=Neodymi...

ive also recently been tinkering with selectively blanking sections of neodymium with heat, so i can say i have first hand evidence that a soldering tip will easily go above 400C https://www.instructables.com/id/Hiding-Messages-in-Magnets-Co2-Laser-Blanked-Neody/

[Gentleheart]

And right you are. Never knew the curie temperature of neodymium was that low. But for ferro magnets it is much higher. (>750° C) Not 3 times higher than soldering temperature but almost twice.
So I stand corrected and the advice is to use ferro magnets for this project.

[querry43]

I suppose you could double up the magnets and replace the outer one as it wears down.

[hollyblue]

I'm about to order parts to build this. The magnet in the picture looks smaller than the size in the link - 50x25x10mm - what size did you use? What is the size of the flat nozzle? Thanks.

[lonesoulsurfer]

Hey there.
I think they must be 20mm x 5mm x 3mm. I'll have a look tonight and work out the exact dimensions and will update the parts list.

[Mad4400]

Great Idea, it would be even better if you could incorporate the pipe into a fume extraction unit.

[lonesoulsurfer]

That's actually a really good idea!

[DanielG707]

Great!

[Gentleheart]

Brilliant idea! Surely will try this out!

[lonesoulsurfer]

Thanks very much. It's come in very handy on a few recent projects

[Gentleheart]

Added bonus: the magnet will disappate some of the heat from the soldering iron.

[RobertC2]

Already have a 3rd hand device?
Add a magnet to any of the metal alligator clips to see if you like how this concept works... then, if you like it, think about making it more permanent; with a larger magnet, perhaps.

[Henmarsh]

One thing I learned from replicating. Lonesoulsurfer's 'ible is that a powerful magnet isn't a great idea. Sure, it hold the components firmly but it also attracts the soldering iron too which is a PITA. Component are light, so less is more in this case and a weaker magnet will work better.