Here is a list of all the postings John Timmis has made in our forums. Click on a thread name to jump to the thread.
|Thread: Chiltern DW!|
It's been a while since the last post so here are a few photos to show the work in progress.
The build has been fairly straight forward aeromodelling so far. The fuselage is a simple built up square structure with a rounded top deck. The wings are built 'egg box ' style with slotted ribs & spars. The washout is jiggled in by the tapered rearspar. It all goes together very easily & makes a nice true wing.
I gave myself some difficulties because I fancied the DW1a with the inverted engine. Although there is lots of room in the fuselage the motor is in the very top of the cowling which is very tight for space. The solution was to make the front of the cowl removable to enable fitting of the motor.
I wanted to use gear that I already had, so this will be a Quantum 40 motor & a 6s lipo.
The construction is more or less finished apart from completing the linkages & cowling.
the model as it stands weighs in at a tad under 5 lbs.
The plan is to cover the wings & control surfaces with dope & nylon with glass on the fuselage.
Hope you like it. More later,
I said I would post a few photos when the build got going so here we go. I hope someone will find them of interest.
The design was by David Boddington & was a free plan in RC Scale Aircraftin the Feb 94 issue. The plan was downloaded from Outerzone & enlarged to 64" wingspan by the local copy shop.
The original plane was a late 1930's racer, designed by two DH apprentices. It was quite successful & the originals can be seen flying at Shuttleworth. The engine in the prototype was a converted Ford 8 sv engine.
The build started about a month ago, this is the progress so far.
It's all been straightforward so far.
More to follow later.
|Thread: Chiltern DW1a plan|
All views & opinions are welcome. Feel free to join in.
I 'm making it electric. Motor will be a Ripmax Quantum 40, 6s battery. Thats what I have. Should have pleanty of grunt.
The prototype first flew in 1937. It was powered by a converted s/v Ford 10 motor, 32 hp. It was a successful racer & had a top speed of 112mph & landed at 35 mph. Fully aerobatic. 3 were built befor the war plus the DW1a with a more powerful motor. Quite remarkable. There ar two examples that you can see flying at Shuttleworth.
Does anyone know where the C/G should be on the model?
Plans are all sorted. Thanks to outerzone, local print shop (only £5) & kc for providing the missing bit of the plan.
It all looks very straightforward thanks to DB. My only concern is the spatted undercarriage which is also very rigidly fixed, smooth landings needed. There is no mention of control throws or C/G position on the plan.
I'll post some photo's when it gets started.
Jim, your model looks great.
Thanks very much, that was a pretty quick response. Yes I was wrong about the title, another senior moment.
I'm planning on building the larger version & converting it to electric. It looks like a straightforward build & being a Boddington design is bound to fly well.
The full size is a very pretty airoplane, built in the 30's. A couple of years ago I saw the two surviving examples flying together at Shuttleworth.
Thanks for helping. Sending a pm now.
I'm looking for a new project, don't like to have an empty building board for too long. This one has been on my 'To do' list for a long time, trouble is I can't find my copy of the magazine. Can any one help please. I can download the plan from Outerzone but it does not show the front fuselage for the DW1a version (inverted engine) which is the one I fancy. The drawing for the inverted engine was shown on a separate page of the magazine. There was also a good 3 view drawing in the mag.
thanks in advance.
|Thread: Van's RV3|
Nigel, Levanter thanks for the replies.
The motor is accessed through the hole behind the spinner, you just need a long Allen key. The motor is fully enclosed . I did make an extra cooling slot in the bottom of the cowl for the motor. I was glad of this when, having fitted the prop & spinner, I came to unscrew the prop nut & the motor spindle turned with the nut & the motor could not be held. Fortunately ,It was possible to insert a length of hardwood through the cooling slot to engage with the slots in the motor casing.
The wing has 2 servos in the center section, one to drive the ailerons via bell ranks & the other to drive the flaps via pushrods & rotary drive. I did it this way because: I already had suitable servos, I wanted to avoid a very long horn on the flaps ( necessary because they are bottom hinged), I like to try new ways of doing things.
I didn't take any photos of the build so I can't show the installation. The drive was cobbled together from bits that were in the workshop ( brass tube , piano wire, couple of collets, Paxolin for the flap boxes). it all works well, the essential things are that the bend in the torque rod must line up withe the flap hinge pins, the torque rod must be a good fit in the flap box.
The photo shows the working pieces, the flap box is 2 rectangles of paxolin separated with ply spacers, I think the torque rod was 14swg, don't make it too long.
Hope this helps. Good luck if you try it.
So how did it go then?
Too exciting by far. More of a first "FRIGHT'.
Saturday morning , batteries all charged ,nice day; what could possibly go wrong?
Well the flight proved two things: there was plenty of power & the c/g was too far back. It really was uncontrollable but was gaining height fast. At fair height the motor was throttled back & I managed to find a rather twitchy trim which enabled one circuit of the field & a safe landing with no damage. Luck was certainly on our side.
So back in the workshop, the flight battery has been moved forward 6" & the ESC relocated above the battery. It's a bit cramped bot it all goes in, just.
Move forward to Wednesday. Now how does it go? In a word BEAUTIFUL. Changed a tiger into a pussy cat. Your Grannie could fly it now.
Looking forward to lots more flying. Very lucky to get away with though. I must have been a very good boy recently.
Latest thing from the workshop is a Van's RV3. Basically it is Peter Millers design ( freebie plan from a couple of years back) enlarged 25% & converted to electric.
I don't like to have an empty building board for too long. With the Hurricane finished,but still not flown, I decided that what I needed was a straightforward scale model (no fussy detail) , robust & with a good strong U/C, about the same size & weight as the Hurricane & using the same 6s batteries.
Power train consists of: Ripmax Quantum II motor, 80amp esc, 6s battery, 13x4 prop. On a fresh battery it gives 1360watts. Weight is a tad under 9lbs.
Hopefully first flight is tomorrow. Pilot looks a bit pale but then she has never flown before & hasn't had time to put on her make up either.
Fingers crossed ( thanks Peter)
|Thread: Aldi bargains|
Thanks everyone for the help & suggestions. The job is getting there although slowly. I am having to stop & clear the nozzle very often. I would like to say that I am a big fan of Aldi & am sure that the problem is with my technique not the kit.
Did anyone else buy one of Aldi's compressor / airbrush sets?
I bought one a couple of months ago & unboxed it yesterday to spray the latest build. I'm using B&Q matchpot paint (valspar) thinned with water. Results so far are disappointing . Pressure is about 35 psi, the paint has to be thinned so much that you get hardly any volume on the model.
Does anyone have any experience or tips?
|Thread: Strange motor behaviour|
Thanks for the replies. I'm in the middle of 2 weeks away from home at the moment & access to wifi is a bit intermitent, I'm not ignoring your replies, please keep them coming.
I don't think it's the battery, I have 2 6s , Both are good & balance well. The motor runs & sounds fine most of the time, there is lots of power but it does sound a bit rough for the short time it slows down. When it picks up again it runs ok.Nothing seems to be getting hot. I'll do some checks when I get back home. It sounds like the esc to me. Will report back.
Yes it's electric.
I'm hoping to be able to pick someone's brains here.
Now that the council have cut the grass & the weather has improved, I've been flying the Chippie.
About 2 min into the flight the sound of the motor changes & it seems to loose a few revs for about 5 or 10 secs, the motor then picks up for another 2min then this repeats again, for the rest of the flight. It sounds a bit like an over compressed diesel. The same thing happens on a ground run, the throttle setting makes no difference.
Any ideas please?
|Thread: Paint masking Advice|
I agree with Martin.
|Thread: Hawker Hurricane by John Timmis|
A very cold garage/ workshop & various other commitments have meant that time for building has been very limited for the past couple of months. Anyway I think that the build is now just about as finished as it ever will be. (Do you ever really finish a scale model?)
A cast lead ring weighing 15 oz has been glassed into the very front of the cowling. The CG is now spot on & the finished weight ready to go is11lb 10oz. So, just need to set up the control throws & checkthat all the screws are tight & it will be good to go. Just need to get my thumbs in practice & some nice weather now.
Here are a few photos. Thanks to all who have followed the build & have contributed. Hopefully there will be some flying photos later.
Need to decide on the next project now, I have a few ideas for a quick build before the "Fury" starts.
Here are some photos of the recent progress. Still some way to go but getting there.
|Thread: Favourite Tools...|
Winch launching gliders. Lots of power under your thumb. 8 litre chevy engine, 400hp, 0-60 in 3 sec. Great.
|Thread: RAF's Finest Biplane? Hawker Fury MkI|
Sorry for the late reply.
Re the bits: please put me down for a hinge set & a vac form spinner. There is lots of time to cut out the wooden bits,most of the ribs are identical profile. Can cut the brass bits myself & will probably do a wooden cowling.
|Thread: Hawker Hurricane by John Timmis|
The receiver battery has been mounted in the lower cowling, underneath the speed controller. It is velcroed onto a ply divider which will also direct cooling air over the speed controller. The fibreglass cowl was cut on the scale panel lines to give access & will be held in place by a tongue & magnets.
The other bit of progress has been the cockpit canopy framing. I wondered how to do this for a while. People always seem to look at the canopy area first so it needs to look tidy. What I really wanted was a frame from litho but this was something I hadn't tried before. Advice was found in an old mag article written by David Vaughan that confirmed that this was a good way to go. The canopy has to be masked off & then the litho framing can be glued down with evostick thinned down with cellulose thinners.
The only tricky part of the frame was the front windscreen frame. The annealed litho was clamped between ply formers & gradually persuaded around the curved edge. Several more annealings were needed before the frame could be cut free.
Hope it doesn't end up a gooey mess.
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