A return to model building and flying. Part 65
And Now For Something Completely Different
At the last club race day, wonder of wonders the weather was sunny and warm and it actually wasn't blowing trees over! I did the most stupid thing imaginable. I had taken two models out of the car boot and placed them on the ground, reached in for the third and stepped back with it. You guessed it! strait onto my 1/2A model reducing it to a jigsaw puzzle, far too awkward around the engine bay to attempt to epoxy it back together there and then, and be sure of it, I would have; had it been humanly possible. Feeling rather stupid, I went out and won the other two classes, not difficult with no opposition; come on guys! But I felt more than a little annoyed with myself.
I hadn't realised until I started writing this that I had been racing this model every month for five years, That is a lot of fun flying for very few pennies......!
we pilot each others models I ended up flying Andy Green's
Hallam Models, T'WING with a PAW 1.5 (pictured right), and what a nice
thing it is too.
It flies on rails, and even managed to hold a power on attitude
like a carrier model when the engine became sick at one point. This
made me remember that I had bought one at the Nationals, and the kit
was sitting on top of my wardrobe. An ideal replacement for the model
I had just trodden on.... I had that sudden itch to build again.
I love Hallam models kits. This is what CL kits should be like, simple, practical, quick to build, lots of fun, and they don't look bad either. This is what you get for your money, a plastic bag of bits. Enter stage right, the T-wing kit.. Taadaaaa!!!
step was fitting the engine. I
always take a lot of time over this, as I find the rest of the model
not only depends on it, but needs to line up with the engine too. Get
the thrust line out of alignment and it will still no doubt fly, but
never properly. It took me an afternoon of drilling and filing and bit
of work with a jig saw before I was happy. Just screwing a PAW in as it
was designed for would not be so involved, but I like my MK17's as they
are more predictable to start; not as powerful as a good PAW 1.5, but
I'll go for reliability every time. I'm surprised no Chinese
manufacturer has cottoned on to the idea of making a modern MK17
equivalent? I'm sure they could be remade with modern materials and
know-how to produce a lot more power.
When I was doing this and starting
to take note of things, I began to realise how good the wood selection
was. Don't know if I was just lucky, but it is very good, with all the
parts fitting snugly... without it being laser cut?
There was only one
error, the bellcrank leadouts don't line up with the holes in the
fuselage. Fortunately all you have to do is make another hole for the
bellcrank pivot bolt the ply reinforcing washers still cover the
original hole; so no big deal. The two pieces of wire in the second
picture are to check the alignment, only the rear hole in the leadout
guide is meant to be used. This in itself suggests that the model is
supposed to be flown with a very forward CG.
Leadout holes prior to moving the
checking the alignment
then went swimmingly up to this point. Then came the finishing bit. I
wanted to see if I could get the epoxy idea I tried on the Phantom to
work.For those that haven't rread my exploits it had been a bit
of a disaster. The idea had been to reduce the number of layers of
paint needed to finish a sheet surface, by sealing the bare wood surface in one
coat with epoxy resin, thus doing away with the dope tissue and sanding
sealer method and all the coats needed before the primer goes on.
However it's not quit as simple as it might seem; but I'm ever the
optimist. The problem last time was the epoxy cured so hard that I had
difficulty working it, so this time I mixed in a lot of micro balloons.
Result.....! negligible effect on the sanding, but it did cure
quicker. Next time I will try heating it with a heat gun after
brushing, as suggested in the instructions, it's supposed to help it
flow and loose some of the brush marks. We shall see?
After the usual primer and rubbing down, I ran into another problem. Out of laziness I used the tape hinges supplied to fix the elevator. BIG! mistake, I could not get them to blend in, and the whole thing was becoming a mess. I made the decision to remove them; oh what a mess! There then followed another hour spent filling and trying to level the holes that had been left.
After that things went fairly smoothly and two coats of car spray later I was fitting the hardware;.Then there followed another Oops! moment. I had used a countersunk screw for the bellcrank pivot to allow the fuel tank to sit a bit closer to the wing; when I tightened, the head pulled through the top ply washer. I got round the problem by using a brass sleeve epoxied into the hole.
I'm also a great believer in tip
weight, as I find it can help a lot in marginal flight conditions(of
all sorts), so I tend to use more than is ever supplied. In this case a
copper coin was twice the weight of the bit of lead supplied and was
neatly buried in the wing; not sitting on the surface as depicted here.
Using a coin as a tip weight
Everything else went smoothly
this is the result, ready and waiting to fly. It's only taken me two
weeks to produce this, which is akin to light speed for me...! And it
would have been even less if I could have got epoxy idea to work
Flying didn't go so well. It launched OK and settled down to what felt like a nice steady flight pattern, but after a few laps she suddenly inexplicably dived into the ground? No real harm done, but puzzling. I certainly didn't do anything and the only thing detached apart from a broken prop blade was the tank still attached to the engine by the fuel pipe. It's possible that it came off in flight and swung forward, as I tend to epoxy tanks in place this is quite possible, and this time I had forgotten to scour the paintwork first; but I will never know? Done properly, it takes considerable force i.e. a hammer and a wood chisel to get a tank off again so I trust the method, it's simple and quick to apply to small models.
needs a few tweaks and minor repairs, and I will try again, but so far
it shows promise. It also gave me an excuse to fit a better size tank
as I miscalculated with the last one, it should have been 30cc not
50cc, that should make sure I can get between 50 and 90 laps on a
The Phantom replica is also having
an extensive and brutal modification to get a bigger fuel fuel tank in,
will be handy as spare model for our club racing. I hate having models
sitting around doing nothing. There really is no
need for the engine bearers to be full width for the full chord of the
wing. I'm also altering the thrust line to try an cure a wandering up
and down in flight.
After a long search for something
will stick bubble canopies in place, I knocked off the phantom one when doing these modifications, it
was never well fixed in the first place, I have found that plain old
UHU glue in the yellow tube is excellent. Even more so because it can
be found in Pound Shops as large tubes. I'm finding that I am using it
more and more. I started to use it on the binding I do in stainless
steel lines, and now I find it's the best thing so far for gluing
control surface hinges into wood. It even reminds me of using balsa
cement because of the smell (oh happy days). Just hope it's not banned
in future by some EU directive because it's solvent based.
New Carrier Deck
My club now has a fine new Carrier Deck, designed by Andy Green to be relatively easily movable. Just needs painting and finishing off now. It is not meant to be portable and will stay on site, but needs to be relatively easily moveable without dismantling to allow for wind direction, be weather resistand and easinly maintained, hence it is bolted and screwed together, and to be able to get it out of the way before any aerobatic pilots using very long lines start complaining about the hazard. Wimps! Land on the deck I say; it's call precision aerobatics after all LOL!
I am still experimenting with the ASP30 4stroke, I still can't start it reliably by hand. Trying out some fully synthetic oil based fuel, did seem to make a difference in that I could actually start it occasionally, after it's usual first rush of enthusiasm the subsequent sulk.The next step was to drastically reduce the amount of oil and see if that made any difference. Short answer, no! I have just about reached the end of the road with this engine, as good as it is in flight I am not prepared to lug a battery and starter around just to get it going.
The only thing what would possibly
get me to use a starter, was a device I saw once in Holland being used
to start a speed model. it was a tube, self contained (batteries
about 30cm long, and maybe 5cm in diameter? but I have never seen one
like it before or since!
I recently received a few emails from John Fletcher in Oz. I'll let John tell his own story:-
Of recent interest is your scanned
magazine section where I learned yesterday from a J E Ballard advert
that the JB “Atom” 1.5cc diesel was designed by a Charlie Gray not John
Ballard as I and many others thought.
Second pic' is of an Allbon Javelin
received seized solid and the conrod was a casualty of
dismantling. New conrod made by me next to it and also has needle
ass'y made by me. I make exact replica NVA's for anything. Make
any part for any engine.
I also rebuild and upgrade Seelig and other timers. Buy and sell on eBay from time to time. Pics are of a Seelig F1C/Open Power timer with extensive mods. such that my modified timers NEVER fail in service. Takes me three days to make the parts for and upgrade a Seelig timer. Also do the Seelig F1J/B "Mini's" to overcome their problems.
I have covered all disciplines in aeromodelling but like you have no great interest in "main stream" R/C. The R/C that I have flown is Old Timer, where it is a little like being able to fly Free Flight and get the models back to the launch point. We live on 10 acres so have been doing a little C/L flying here on the property. I have a "Peacemaker" with Rivers Silver Streak 2.49 Mk 1 that is an absolute delight to fly, the engine flying through all circular manoeuvres without sagging or misfiring. Starts first flick too.
Rivers Silver Streak MII with prop. driver and NVA made by me
The ETA 15 Mk III which has spinner nut and washer, prop. driver and collet, Philips head screws in stainless steel, the tufnol rotor and the NVA all made by me. Doing the screws was challenging, I cold forged the Philips recess then after machining the head to shape with form tools I ground to the exact curves I lightly glass bead blasted the screw heads to replicate the nickel plate of the originals. The ETA's nickel plated brass NVA parts I made in nickel silver so it's the same colour all the way through. Ratchet clip marked out, hand cut, formed to shape in annealed spring steel then hardened and tempered, chemi blacked and lanolin dipped.
Doing work for others as I do,
time is my problem!
power to your elbow John, and long may you enjoy what you do.
Different way to display the Model
I mentioned some time ago that I was looking into the prospect of getting you all to use a document viewer to read the magazines from zip files without having to unpack them first. this would alieviate the need for me having to display them on the web pages also. This would save me an awful lot of work.
I am still looking into it, to find
suitable viewers for everyone. The screen grab is of a copy of
an Linux application called 'Comix' for viewing comic books in various
compressed formats, displaying a couple of pages of a Heavy Metal
that it can display the pages two at a time as you would see the real
paper copy, and gives a flavour of what it would look like to
view the magazine files in this way, full screen with no distractions
is even better.
Comix viewer running in Linux Mint
with an LXDE desktop