Cool Tools: Flux!

I’m a believer in using the right flux for the job, and as such I keep a variety of electronics fluxes on my bench. Here are some of my favorites.

MG Chemicals 835

835-100ML

MG Chemicals 835 is an electronics-grade activated rosin (RA) flux that is useful for a wide variety of soldering applications. The high activity rosin formula is helpful for soldering corroded copper wires and oxidized components or tarnished copper clad. It’s readily available at most electronics stores, inexpensive, and versatile. The biggest downside of this flux is that since it contains a very high solids content (50%), it tends to leave gummy rosin residue on everything it touches (including your fingers). This flux is also available in a flux pen. The RA designation implies that all flux residue should be thoroughly removed after soldering to prevent long term corrosion and electrical leakage.

Kester 186

Kester 186 (datasheet) flux is a lower solids content RMA flux (36%) and IMHO the ideal compromise between activity and residue. If I had one flux on my bench, this would be it. Kester sells it in flux pens or by the gallon (and one gallon will last years in even the busiest prototyping lab) but fortunately you can buy smaller bottles on eBay. Kester claims the residue can be left on your PCB but I usually clean it off if long term reliability is a concern.

Kester 951

Kester 951 (datasheet)  is a low solids (2%)  rosin-free no-clean organic flux that is useful for situations where cleanup would be difficult or impractical and flux residue must be minimized. This flux is surprisingly readily available on eBay and seems to be very popular with the Xbox repair crowd. It is the lowest activity flux I have on hand and can be frustrating to use if the components to be soldered are anything but spotlessly clean. During soldering, this flux remains active for a matter of seconds before largely evaporating. I would avoid it unless you’re doing really fine work (eg. soldering close to bare die) where removing flux residue might damage bondwires or sensitive components.

 Flux Dispensers

FD-21

These Plato flux dispensers are my favorite dispensing tool and are perfect for applying a precise drop of flux to just the right spot on a PCB, minimizing mess and cleanup. They are inexpensive, high quality, and easy to use. These are available from many distributors (Techni-Tool, Mouser, etc.), but I usually order from All-Spec because they typically have the best pricing. I prefer the Plato FD-21 (0.010″ needle) for thinner fluxes such as Kester 186 and the FD-2 (0.020″ needle) for thicker fluxes like MG Chemicals 835.

Cool Tools: Menda 35622 Spudger

Menda 35622 Spudger

The Menda 35622 spudger (datasheet), an official Apple repair tool made famous by ifixit’s iPhone repair guides, is handy for all sorts of spudging(?) applications, including bending, prying, pushing, shoving, tweaking, twisting, scraping, and soldering.

These are now readily available from most electronics and phone repair shops, but I usually buy them in bulk on eBay.

You can also find them on amazon.com:
Menda Soldering Probe, Nylon, 6″ OAL, Spudger

Another option: These orangewood sticks from Techni-Tool are also great for pushing and prying. Since they’re disposable they can also be used for things like mixing epoxy!

Cool Tools: DealExtreme Edition

Dealextreme is home to a few good buys on electronics prototyping supplies.

Here are a few of my favorites.

Thrum scissors

DX Thrum Scissors

These miniature thrum scissors are handy for opening ESD bags, trimming the ends off of SMD component reels, and cutting kapton tape, among other things. I keep several pairs at work and at home and use them all the time. They are much more precise than standard scissors and good for all sorts of light duty applications. (You can also buy these from amazon.com here: Blue Handle Stitching Yarn Thrum Scissor Tool 3 Pcs)

ESD Tweezers

Lodestar tweezers

These Lodestar L601110 ESD tweezers are perfect for all sorts of electronics prototyping and repair work. I find them very useful for surface mount assembly and rework, but I also use them for precision gluing, discharging SMD caps, shorting traces on PCBs, and also sorts of other off-label uses. They are cheap enough that when I bend or otherwise damage one set, I’ll throw them away and buy another. If I only owned one pair of tweezers, it would be these.

Configurable Storage Boxes

Storage boxes

These configurable storage boxes seem to be slightly lower quality than the ones offered by Adafruit but are a tad bit cheaper and a nice add-on item if you’re already placing an order at DX.

45-in-1 Multi-tip Screwdriver Set

 

Multi tip screwdriver set

This 45-in-1 multi bit screwdriver set is  decent for the price and generally useful for disassembling a wide range of consumer electronics devices.

Update 1/2/2015:

Chris Jones (@chrisgj198) pointed out a few items I missed!

 

 

Cool Tools: Design Easy SMD Component Kits

Introduction

Inspired by Kevin Kelly’s book Cool Tools: A Catalog of Possibilities, I have set out to document tools that I find particularly interesting or useful, primarily in my work as an electronics hobbyist and professional electrical engineer. This is the first post in that series.

Design Easy SMD Component Books

Design Easy SMD Kit

These SMD component books are super handy for all sorts of electronics prototyping, construction, and repair projects. I bought a full set of these books for my lab bench at the office some time ago and and have found them invaluable. I liked them so much that I bought a second set for home!

R0402 kit detail

I prefer these component books over other types of SMD kits such as trays, bins, drawers, or bags because they don’t take up much space on the shelf and they keep components nicely organized in order by value.  Components are easy to access and hard to mix up.

There are many other vendors on eBay and aliexpress that sell component books just like these, but I like Design Easy because they have reasonable prices and carry resistor and capacitor assortments from size 1206 all the way down to 0201. You can save on shipping by ordering a complete set at once.

Here’s a snippet from their eBay store:

0402 practical book: ( resistor 63value 3300pcs )+( capacitor 17value 950pcs )
0603 practical book: ( resistor 63value 3025pcs )+( capacitor 17value 700pcs )
0805 practical book: ( resistor 63value 3025pcs )+( capacitor 17value 700pcs )
RF practical book:    ( 0402 capacitor 12value 600pcs ) + (0805 capacitor 10uF 50pcs ) + (0402 high F inductor 38value 1900pcs)
0201 resistors: 106 values, 50 pcs/value, 5300 pcs in all
0402 resistors: 170 values, 50 pcs/value, 8500 pcs in all
0603 resistors: 177 values, 50 pcs/value, 8850 pcs in all 5%
0603 resistors: 170 values, 50 pcs/value, 8500 pcs in all 1%
0805 resistors: 177 values, 50 pcs/value, 8850 pcs in all 5%
0805 resistors: 170 values, 50 pcs/value, 8500 pcs in all 1%
1206 resistors: 170 values, 50 pcs/value, 8500 pcs in all

0402 capacitors: 80 values, 50 pcs/value, 4000 pcs in all
0603 capacitors: 90 values, 50 pcs/value, 4500 pcs in all
0805 capacitors: 92 values, 50 pcs/value, 4600 pcs in all
1206 capacitors: 38 values, 50 pcs/value, 1900 pcs in all

Their “practical book” series contains an assortment of SMD resistors and capacitors in one book, while the separate resistor and capacitor kits are more complete and IMHO generally more useful, particularly if you use capacitors a lot and need a wider assortment of values.

Bonus: If you want to create your own component assortment or add extra pages to an existing one, Adafruit carries Blank SMT Storage Books and extra Storage Pages.

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