Subject to some time over the next 50 years on learning how to,
and then getting round to, trimming and polishing the marble slab,
the vibrating Morse Keyer previosuly discussed may be viewed
in the Blog pages at
The keen-eyed amongst you will have noticed that it has been
bodged together with bits from a hoarder's dream. There is a
proliferation of the knurled brass screw tops that used to adorn
the 4 1/2 volt Ever Ready batteries (probably 45 years in the
junk box, bound to be useful someday!), the two contact pillars
are fashioned from the pins of round-pin mains plugs, and the
connections are to two Binding Posts of 1930s vintage.
Appropriate, perhaps, for a replica of a machine that was patented just over
100 years ago?
Although the construction looks a bit chunky, the working bits
are in fact the same dimensions as the Vibroplex from which it was cribbed.
The base is bigger because it was a piece of scrap ally in the junk box.
The marble has to be large to match the base.
I have long wanted a Morse Key where the operating lever was at desk level,
and I have achieved this with the right-angled drop down,
For a rather unusual use:-
(OK, I cannot deny your curiosity. I want to graft selected
seedling alders onto "Adult" trees. There is no problem
about the woodwork, but they just don't "take". Some people
graft alder cultivars onto potted trees which they lay
across a hot pipe (How hot? I don't know yet), and then the
graft "takes". But you can't do that with rooted trees in
the outdoors. So I used 24 volt AC from a transformer,
feeding 2 KOhm 2 watt resistors (about the same diameter as
the alder twigs) taped to the twig, wrapped round with 10
cms of bubblewrap (which can't get waterlogged, about 3
turns) which gives a temperature about 10°C above ambient.
That seems just cosy. But it didn't work! The grafts died!
Why not? 2 possibilities have been suggested to me:-
1) The heat is too localised.
2) Voltage gradients are set up on the twigs which kill them.
I am doubtful about both, but I must try them. One of the problems is
weight; these twigs are 2-3mm in diameter at the end of long branches
and there is limit to what they will bear.
One possibility is to tape the resistor to one side of a sachet of
some liquid, any liquid, so long as it's not too expensive, and tape
the other side to the graft. Possible!
But rather better it seems to me, is to use that kind of soft sheet
metal that toothpaste tubes used to be made of. I would simply wrap
one turn round the resistor and the second turn the other way round
round the twig, making a kind of figure of eight (8). That would both
supply uniform heat to the graft and shield it from electrical fields.
But where do you get such soft sheet metal? Does any kind of
toothpaste still come in it? Where can I get it? What is it CALLED?
You can't ask for something which you don't know the name of!
Shooting in the dark!
Could get some lead flashing and a set of rolls to roll it thinner or even
beat it thinner with a planishing hammer. Alternatively, you could treat
yourself to a few bottles of decent wine. Check the cover over the bottle end
before purchase, since you don't want the cheap plastic stuff :-)
Does the air-graft actually need to be heated at all?
What I have actually done is use cut-up disposable "aluminium" pie
trays from the supermarket. It's not as thick as "card" but it's
thicker than ordinary paper. It folds and then holds its shape in a
handy way. It will certainly shield the graft from the voltage
gradients and it really ought to distribute the heat, about 0.3 watt's
worth, 10 °C.
That is the question to be answered. Others say that it works, but
heating it electrically, I couldn't make it work. So, on un-grafted,
normal branches,I am investigating possible causes:-
1) That uneven distribution of the heat is the problem. I am testing
that as described above by using thin sheet metal to distribute the
2) That the voltage gradients are the problem. At first I was very
sceptical of this - 24 volts is not a killer voltage!, but now I have
come round to thinking it is quite likely. I am testing it in 2 ways:-
a) Simply taping a wire to the branch.
to produce voltage gradients across the branch
b) Taping a wire to the branch, but cutting back one of the
to produce a voltage gradient along the branch.
Let's hope a result appears before the branches loose their leaves for
If you have stone masons in the area then they often use a very thin
sheet zinc, IIRC for templates. My local engineering supplier Avery
Knight and Bowlers in Bath stocks it. It is about 0.5mm thick and easy
Thank you. It's amazing the variety of sources that have been
suggested on other groups, Euthymol toothpaste, Tomato puree, Kavli
cheese tubes... Seek and ye will find indeed! Your suggestion will go
onto the list. Thank you.
Ouch that's expensive.
Any reason you can't use lead roofing flashing? Code 3 (3 lb/sq ft)
should do, about £30-40 for 6m by 150mm. Bit thicker than foil, but is
there any harm in that?
I think copper would be a mistake here, possibly toxic.
Can you use DC rather than AC? If you use shielded cable with the shield
grounded you shouldn't have much in the way of electric or EM fields
near the plant.
Weight may be a problem. These are thin branches at a long reach.
I could use DC. Then does it have to be perfectly smoothed? Where do
you stop? Before I explore these avenues I'll see if I can make what I