Third Hand++: A multi-use helping hand for electronics and other delicate work. by rstraugh
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In the past I've used the third hands/helping hands available at chain electronics shops and have been frustrated with their usability. I could never get the clips exactly where I wanted them or it took more time than it really should to get setup right. I also wanted the ability to hold small circuit boards and alligator clips just don't do a very good job.

I was familiar with the adjustable coolant hose systems used to spray coolant at cutting tools in the machining industry and thought that would be a great place to start. I ordered various nozzles and hose segments from my favorite online machine tool supply company and started experimenting. This is what I came up with. While it still has plenty of room for improvement it has served me well over the last 3-4 years.

These arms can be placed into pretty much any position and they will stay there.

Another nice feature is that you can make all sorts of attachments for holding whatever you need to work on. So far I've made a circuit board holder, a clamp, a mount for an LCD, and an extraction fan for keeping fumes out of your face.

All you really need are some simple hand tools, a couple taps, a drill bit and a drill to make the basic version. If you have all the tools you need, it can be made for $20 or less.
 
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Step 1: Getting Started

Third Hand:Parts and Tools.jpg
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The first step is to gather everything you'll need.

Tools:
- Drill (A hand drill will work but a drill press would be better.)
- 3/8" drill bit
- 1/8-27 NPT tap
- 6-32 Tap
- A tap handle
- Ruler
- Center punch

Don't forget safety glasses!

Parts:
- The Base:
I used a block of 1/2" thick aluminum (5.75"x2.5"x0.5"). Aluminum is heavy enough to be stable and is easily tapped. You can use whatever you want as long as it is at least a 1/2" thick and can be tapped. (Plastic, wood, MDF, steel, etc...) The lighter the material, the larger the base needs to be in order to remain stable. If the material is too soft the threads will wear out and the arms won't stay in. If you don't have a local source for the aluminum you can order it from an online metal sales company cut to length for about $6 plus shipping. I have used www.onlinemetals.com for other projects in the past.

- The arms:
The arms are made from coolant hoses and nozzles used in the machining industry to keep cutting tools cool and lubricated. I used the Snap Flow brand coolant hose system which I bought from www.use-enco.com. They sell a "Male NPT Hose Kit" that has 13" of hose and an assortment of nozzles and connectors. That gets you most of what you need to make a two handed Third Hand. I'd recommend buying two kits and a few extra nozzles and connectors. For around $12 you will have more than enough parts to make 4 arms.
For each arm you will need:
- One 1/8 NPT connector
- 4-5" of hose
- One 1/8" 90 degree nozzle.
You may want to consider buying the hose assembly pliers for $23. They are a little difficult to snap together by hand. I didn't buy the pliers but I kind of wish I had.

- The Hands:
Each hand is made out of a banana plug threaded into the 90 degree nozzle and an alligator clip. I chose the "Flexible Banana plugs (2-Pack)" from radio shack because it has 6-32 threads that will thread into the nozzle. The alligator clips are the standard 2" size.
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nwlaurie says: May 18, 2013. 2:27 PM
I'm very taken with this but not kitted up for drilling and tapping. I'm wondering whether this is (yet another)opportunity to get the SUGRU out! I'm going to order a 13" length of the hose material from eBay and have a fiddle.
GREAT instructible because you are SO right about the two-armed, ball-jointed, easily-broken magnifying glass type of gadget.
Archy says: Apr 22, 2013. 4:58 PM
I'm building the same thing, with the magnet fittings from locline instead of tapping my steel block.
However, since I'm using a 14x14"x1/4" steel panel as a workspace as well, I'd like to coat it so it's not a bare metal surface that is a) conductive b) hard (dropping delicate components) c) slick (said components rolling off, and if unbroken before, broken upon falling off the surface).
I've put a fair amount of time into googling things like "rubber metal coat", "coating metal vinyl", etc. But the best I've come up with is plastidip. It seems that plastidip is really susceptible to sharp edges, which concerns me, as removing the magnetic mounts will probably require me to leverage them against their edges.
I need a durable, soft/rubbery coating for steel.
So, any ideas for what I'm looking for, or how I can search better?
hamstermaster says: Mar 18, 2013. 8:46 PM
do you have a step by step video tutorial on how to make this? this would be very beneficial for those who are physically disabled, its an easy DIY alternative for the medical stainless steel.
vickybacon says: Feb 5, 2013. 1:10 AM
If you happen to be living in the US, I found a great site alternatives who also can supply affordable yet reliable stainless steel bars and other steel structures.
Malaclypse says: Nov 17, 2012. 7:29 AM
You would be better off getting an "R" (.343) Drill and a #5 Center Drill after using the center punch. The center drill will give you a good pilot hole and if you find one with an 82 degree chamfer on it, you will also have a good leading edge for your threads.

Although, 3/8" (.375) will work because of the nature of NPT taps, and since you aren't using it for anything but structural support, it should be fine.
Malaclypse says: Nov 17, 2012. 7:35 AM
Also, USE A VISE! Drilling through any kind of metal while holding it in your bare hands in a REAL quick way to get hurt if it grabs when breaking through.
Boaticus says: Jul 5, 2011. 5:06 PM
Great instructable! I made the 4-armed part tray version. Also added a sheet of 1/16th thickness neoprene rubber to the bottom for more traction and less scuffs on the work bench.
IMG_0203.JPGIMG_0204.JPG
buhari444 says: Aug 22, 2012. 3:09 AM
hey whats the total expensive for this project .........
bwdidwhat says: Dec 8, 2011. 9:53 AM
You did an amazing job on that. Just saying.
zeremy says: Sep 24, 2011. 11:21 AM
i really have to have one of those trays
flamekiller says: Aug 21, 2012. 10:33 PM
Just build one up for myself ... haven't actually used it yet and it is already orders of magnitude better than your typical "helping" hands, at not much larger of a price.

Added a few bits of my own (well, a sunk dowel as a solder spool spindle). Would like to mount the soldering station on the board, but it doesn't have keyholes (next generation, Sparkfun, next generation!)
flamekiller says: Aug 21, 2012. 10:38 PM
Hey, how about some photos ...
IMAG0521.jpgIMAG0522.jpgIMAG0523.jpgIMAG0524.jpg
enderwigin says: Aug 19, 2012. 12:33 PM
This is my finish product. I had to epoxy some of the bolts in place cause i could not thread the metal. (it was to thin) i hope you like.
IMG_20120817_151538[1].jpgIMG_20120817_151446[1].jpgIMG_20120817_151522[1].jpg
jwmallett says: May 27, 2012. 9:32 PM
I saw this instructable a few months back and acquired most of the parts. Thank you for this instructable and others who have taken the time to post their ideas. I was deciding on which type of platform to get. In the meantime, I saw this portable work vise. I paid 30 bucks for it with shipping on ebay. Most of them are a few dollars more, maybe expect to pay 40-50 with shipping. Little did I know when I purchased it, I found out that you can tap the brackets that hold the boards and the coolant hose screws into it securely. I saw a post on here about an addition of a Irwin quick grip, I think this one is a micro or mini. I was going to get around to tapping the other three, but after using this, I have abandoned getting a platform and building a table version. This thing rocks! I can fit the tiniest DIY boards snugly in the vise and quickly adjust it to secure and area. This is extremely useful for getting to both side of a circuit board, and the table is heavy enough that I can apply enough pressure to effectively pull components, etc. Plus this thing can be used for all sorts of things. Keep the ideas flowing!
Workbench Vise.JPGphoto(1).JPG
jwmallett says: May 27, 2012. 2:43 PM
BTW, the tap I used was a 3/8-24 found on ebay. Also I want to note that, there is a hole in the hardened rod that the blue plastic mold goes through, its about a quarter inch in diamter. I think I used a 3/16 bit and just happen to hit it! on the back side I drilled a 3/8 hole, if i remember correctly and was able to force fit the attaching peice. I put a machine screw in from the back side ( i think it was #10 or #12), sorry it has been a month or so, I cant remember, but it was bigger than the hole in the straight nozzle. Fit through the hole that was machined from the factory. Then I added some epoxy for good measure on the inside of the nozzle. then trimmed the screw and added an acorn nut and washer and tightened it up. Works like a charm!
jwmallett says: May 27, 2012. 9:52 PM
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quaeredeo says: Feb 20, 2010. 7:06 AM
Please would someone make one and let me buy it from you. What would you charge to make one for me? quaeredeo@comcast.net
Schliermaaker says: Apr 5, 2012. 6:14 AM
Take a look at;

http://www.exltek.com

http://www.exltek.com/Products/Lookup.aspx?ItemNumber=Clip_Sticks_14
foxmcf says: Dec 29, 2011. 1:12 PM
I searched over and over again for the 'perfect' soldering station. This is definitely it. I ordered my hose kit from enco on Monday, and they arrived today. Thank you for the great instructable! I also ordered a couple of these magnetic vise grips, and together your possibilities on soldering configuraitons are endless.

Here is a link. If the link stops working, search google for "Napa 77-4025 Magnetic Soldering Clamp Vise"
http://www.ebay.com/itm/Napa-77-4025-Magnetic-Soldering-Clamp-Vise-/250933642527?pt=LH_DefaultDomain_0&hash=item3a6ccf851f
stagebuilder says: May 27, 2009. 9:04 PM
It's usually better to just drill through metal with the size bit you want rather than using a "pilot" bit like drilling in wood. It will cause your larger bits to wear unevenly. So just use the size you wish and go slowly, gearing down the drill press if you can, and releasing every now and then rather than forcing straight through. Also, you should always use a lubricant when drilling any metal. This will also save your drill bits.
rstraugh (author) says: May 28, 2009. 5:32 AM
Cool, thanks for the pointer. I've wondered about that. Often I'm using a hand drill and find it too difficult to drill all the way through in one pass with large bits. But, I can see how that would wear out the outside of a bit faster.
qualia says: Jul 9, 2009. 3:26 PM
conversely, if a straight hole without the drill wandering is the objective, or when going through hard materials, like annealed tool-steel (hardened tool steel drilling = fail) , sometimes it is good to drill a pilot hole and go up in bit sizes till you've got the hole size you're after. dont try go in drill bit steps of more than 2mm larger than the last, or it will srsly rip up the tip.
johnpeck1 says: Jul 25, 2011. 8:17 AM
I drill metals all the time. I use a small pilot hole, 1/8. Then finish it with the proper bit. This makes a clean hole and saves your bigger bits point. Makes a perfect hole every time.
mildsteel says: Jul 7, 2011. 10:49 PM
good idea, but be careful when doing these things because some equipment are hot on working times.

http://www.metal-supplies.com/12201/index.html
hi111 says: Feb 11, 2010. 7:59 PM
 Could you please give links to the exact things you used?
Tanks in advance!
nbagf says: Jul 3, 2011. 2:28 PM
male npt hose kit 
right angle 4 pcs kit 
1/8-27 NPT tap
6-32 tap


hows that for a part list ($25.49 without tax or shipping costs)

natter37 says: Jun 12, 2011. 11:39 AM
is that actually called "Coolant Hoses"? cos when i try and find it it only comes up with hoses :/ is there another name for it?
superjail3 says: May 30, 2010. 8:53 AM
 couldnt the base be wood otherwise great instructable
ZeroTruths says: Jul 11, 2010. 5:39 PM
Yes, but then you'd need to find a way to add more weight so that it wouldn't tip over as easily.
TheGreatS says: May 16, 2011. 4:59 PM
Or you just make a bigger base.
slithytove2 says: May 1, 2011. 2:32 AM
I have been browsing some of the loc-line products (officially retailed at http://modularhose.com/) and had a few ideas:

They sell a magnetic base (though for the 3/4" system, item 60532) (just need to get the converter to go from 3/4" to 1/4" or 1/2" if you want a smaller one)
Using two of the Y-Fittings (item 41408) you could get 3 arms, with one set apart from the other 2 (this would actually allow greater range of motion that the fixed base)
Alternately you could use a solid 4-way cross (item 41498)

While coming to a bit higher price than above (about $35, $13 of which for the magnetic base, which could be built for cheaper), it would create a more modular and flexible system.
steel plate says: Feb 15, 2011. 11:35 PM
http://www.ysteelplate.com
wjulaxer13 says: Aug 20, 2010. 10:13 AM
what would be considered the max temps that this hose will handle? I would like to make this to handle braising temps which are quite a bit higher than standard soldering. thank you
maurice1993 says: Jul 20, 2010. 2:11 PM
I wann one just like the last one, with 4 hands, how much? =]
techturtle2 says: Jul 3, 2010. 9:56 AM
I have that same soldering iron. be careful with it it gets WAY to hot! :)
joerice01 says: May 21, 2010. 1:47 PM
 What are you using to filter on the back of the solder fan?
ngenius says: Dec 10, 2009. 12:16 PM
What machine was used to mill the parts trays into the aluminum?
u_r_teh_svck says: May 16, 2010. 6:17 PM
its called a milling machine
112251919112 says: May 15, 2010. 11:13 AM
Have you ever that of marketing this?
urbanwoodswalker says: Apr 27, 2010. 9:20 AM
Ok, I definately need these...I am in the USA....anyone figure out how to make one with US materials?  Or, a link to getting the hoses here?


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