Gertboard - The Element14 strikes back

Hi Ray.  I have been following this discussion and feel that the following may be of some help to you.

In a late eighties I toured the UK with the DTI mobile automated Electronics Factory demonstrating  surface mount techniques and all the other advanced manufacturing in electronics techniques coming to the forefront at that time.  After this I spent some time at the Highbury college in Portsmouth running the surface mount technology workshop.  At that time IBM had a local factory, and it was trying to cross train all its employees and their idea was that if everyone was flexible, then the factory would become more efficient. The factory made hard disk drives and there was a small surface mount board incorporated in that device. The idea was that they could take a storeman or perhaps a fork truck driver and get them to assemble surface mount boards the same way that the young female operators did.  So, without asking me if I thought it was feasible - IBM was always right -  they commissioned me to run a series of workshops to do the training. This just really did not work because the men not only found it very difficult to hold the tools and components steady, but also to see what was going on without powerful magnifiers.  The young females found it easy and produced high quality work. Needless to say, the experiment was abandoned after a short time.

So, everything you have said in this discussion is validated by my experiences. However, I feel sure that the posts I make over the coming weeks will give you hope and enable you to complete a satisfactory kit build. Must stop now as I have run out of time. For the record, I was born before the WW2 rationing started, but still expect to complete a Gertboard kit build which will work first time.

Very interesting post, cityswift, and inspiring too.

Thanks for that Cityswift and I look forward to your additional posts. Us old dogs still got a few tricks in us eh?

Ray

About making soldering easier- I recently realized that one reason it's easier to solder at work than at home (apart from the nice binocular microscope) is that we have Metcal MX-500P-11 soldering irons. With that unit, the tip is only 4 cm away from the hand grip, making precision work easier.  I could not spend $500 for my own Metcal, so at home I have a cheap Radio Shack iron with a tip about 8 cm away from the grip, so it is 2x as long. That means any deviation in the angle of my hand is multiplied 2x at the tip relative to the Metcal, and that makes a real difference with accuracy.

Is there any affordable iron with a short hand grip - tip distance? Or is that not practical with a simple, conventional iron (the Metcal uses RF heating right at the tip, so there is no separate heating cartridge to design around).

jbeale wrote:

 

we have Metcal MX-500P-11 soldering irons. With that unit, the tip is only 4 cm away from the hand grip, making precision work easier.

That is an excellent observation.

PS. I have a very old Bausch & Lomb 20X binocular microscope fixed to my worktable, and when I set its 0.7-3.0 zoom to the lowest magnification I get 14X and am able to solder tiny features reasonably effectively.  Good hand control is really difficult though, so your point rings a strong bell.  I'll be looking out for shorter soldering irons.  A pic here for background:

http://www.flickr.com/photos/morgaines/6172845302/in/set-72157627604533547

Morgaine.

Thanks jbeale and Morgaine. Excellent tips (pun intended) about shorter irons  Mine is about 3 or inches from holding point to tip, Perhaps a shorter iron would help steady my wobbles or I need some oven gloves.

Ray

Morgaine Dinova wrote:

PS. I have a very old Bausch & Lomb 20X binocular microscope...

If I had a binocular microscope, I'd just use my laser vision!    It doesn't work with a magnifier or monocular microscope or video monitor.

There's a joke about sharks and overlords there somewhere, but it refuses to materialize.

I have looked at the Gertboard assembly manual and the soldering instructions are basically

1. Solder iron in

2. Solder in

3. Solder out

4. Solder iron out.

I think the process deserves more coverage than that, as if you have an understanding of what is happening, then you have much better chance of doing it correctly.

This is what happens when you make a joint using 60/40 tin lead solder wire with a rosin flux core and an iron tip temperature of around 270 degrees C.

1. All surfaces must be bright and shiny to start with.

2. The tip is applied to the surfaces being soldered to bring them up to its temperature.

3, The solder is fed into the joint and it melts a 185 C releasing the now molten flux into the joint. The flux is inert at room temperature but becomes molten at 120 C and mildly acidic so that it dissolves the thin layer of oxide on the surfaces allowing the formation of a pure alloy. This is the process known as wetting, and the flux is the key to its achievement. The solder is then withdrawn.

4. The tip is removed and the temperature drops rapidly and the solder solidifies at 185 C and the flux residue solidifies around 100 C and reverts to its inert state. The components must not be moved during the freezing process so some method of achieving that needs to be implemented.

I am sure that many of you will already know this, but I thought it worth repeating so that you start on a solid foundation.

I have ordered bits to test out some ideas and more will follow.

Dave Tedd

I have some real probs with hand shake any good tips? would be VERY welcome. (cushion rest etc)

My 2p suggestions are to have a deep desk with a good non-slip rubber esd mat. You try to lay the board as flat as possible and solder with your full forearm resting on the desk. It's not always possible, but helps a lot.

Referring to what cityswift said, a very common sight within the electronics manufacturing industry would be a young female operator sat at a deep desk with chair set quite low, arms resting on the desk soldering away.

I see others mentioning the helping hands things, the problem I always have with those and similar (I use a small vise to hold stuff when it really shouldn't move) is that the extra few inches of height they add leaves me with nothing to steady my hands on and even more hand shake.

Find something that works for you and go with it.