By continuing to use this site, you agree to our use of cookies. Find out more

Member postings for David Davis

Here is a list of all the postings David Davis has made in our forums. Click on a thread name to jump to the thread.

Thread: Trendsetters and Iconic Models over the Years?
18/01/2020 05:30:42

Radio Queen

Four Star 40,60 etc

Goldberg Tiger

Calmato Alpha 60

Thread: Do you love some of your engines so much you don't fly them?
17/01/2020 11:52:52
Posted by Don Fry on 17/01/2020 11:12:19:

Small point David. My (failed) trainee is selling his kit. In the kit is an OS 40 FP. and a Thunder Tigre 42 GP.

Both are simple plain bearing trainer type things. Both start easily, with good throttle transition, and reliable tickover, in other words nice little engines. IRO, €20 each.

Thank you for the offer Don, I have never considered myself to be an engine collector but I am an acquirer of unconsidered trifles!

It was a nice day yesterday and as a reward for having finished digging a trench in the garden, one of two required to build a path on sloping ground, I had a play with some of my engines which could possibly be used in a 40 sized trainer. I managed to get the following to run on the test stand: Webra 40, Super Tigre 40, Enya 45 and OS 40 FP which used to power my Fun Fly, so I'm not short of suitable engines.

fun fly apres maiden..jpg

I also own three Irvines and the Enya 50 any of which I could use.

If I do replace the Boomerang I will think about installing an electric motor but probably end up running the Enya 50!

17/01/2020 10:40:31
Posted by Andy48 on 16/01/2020 22:43:25:

A little off topic, but the OP's story raises a few interesting issues.

1. By the time students have got to the confidence stage of take offs and landings surely they should have their own plane and one buddy boxes to that.

2. I don't have any sentimentality about my electric motors seeing as they are as cheap as chips.

3. I love the quick take back system I have on my Frsky gear where I regain control instantly simply by moving the joystick. It is that difficult time where you just give them that extra fraction of a second to self correct that this works best.

I have my own training programme Andy which goes like this;

  1. Left hand circuit.
  2. Right hand circuit.
  3. Horizontal figure of eight.
  4. When the trainee has reached this stage I teach him how to take off.
  5. Loop
  6. Roll, these two manouvres are part of the French Brevet A Qualification if using a four-channel model.The Brevet A is the equivalent of the BMFA A Certificate but a bit more involved.
  7. Once the trainee has mastered these manouvres I teach him how to land but at this stage I insist the he has his own model!

However, my trainee had only reached Stage 3 of the training programme when he got into difficulties. As I've said above,I failed to take back control quickly enough and this happened...blush

enya 50 and boomerang.jpg

If I buy another Boomerang I may power it by an electric motor, I've no emotional involvement with them, but then that Enya is so pleasant to use and to listen to.

15/01/2020 13:59:19
Posted by Brian Cooper on 15/01/2020 13:46:07:

Yes. . . I have an engine which I keep as a "treasure". . It is, however, a most unlikely treasure as it is just a humble Merco .49 with a twin plug head.

The engine has no real intrinsic value, and it isn't even that pretty BUT it is treasured is because I bought it new (about 54 years ago) when I was 12 years old, and it is a shiny artifact from my childhood. . . It took ages to save up my pocket money for it, plus, it was my first "big" engine.. lol. . . There are a lot of happy memories in that old engine. thumbs up

B.C.

Funny that Brian, I bought an Enya 35 of eBay for a few quid last year. It was in its original box with both cylinder heads and all of the paper work. It had been mounted in an airframe, marks on the lugs, but never run. This engine also has no monetary value but I can't see me starting it, flying it or selling it! Something else for the significant others to deal with when I drop off the perch!

15/01/2020 13:53:48
Posted by Don Fry on 15/01/2020 13:40:01:

... Back to post, what is your hole spacing David, or is a strap on necessary because a manufactures silence won't fit the airframe.

edit, senile, forgot the point of the post. What happens to the motor when you fall off the perch, start reading the instructions for stall speeds of these wings you've been issued with.

Edited By Don Fry on 15/01/2020 13:43:38

Don, the OS 40SR and the Enya are early engines with threaded holes for the silencer each side of the exhaust port. On the OS the part of the exhaust port, towards the back of the engine, has broken away. On the Enya the silencer mounting bolts have sheared off in their holes. Hence the need for a strap-on silencer.

The other OS is an as new rear exhaust engine which is intended for a Peter Russell 363.

15/01/2020 10:40:17

Any of you feel the same way as I do about some of your engines? Over-protective perhaps?

Let me tell you a little story. I do a fair bit of instructing and have or had, two i/c trainers and an electric foamie with which to teach beginners. One of the i/c trainers is something called a Primary 40 an eminently forgetable ARTF trainer powered by an Irvine 40, the other was a Seagull Boomerang, my favourite ARTF trainer BTW, powered by an Enya 50. This is a lovely engine and fitted with the Q silencer it sounds lovely too! The problem with teaching beginners is that you go through about five stages before they are competent to fly on their own.

To begin with you are for ever taking back control on the buddy box as their turns become spiral dives!

The second stage occurs when they are not making so many mistakes but in a ten minute flight you may have to take back control three or four times.

By the time they reach the third stage they are capable of flying basic circuits and horizontal eights but sometimes get into trouble so you have to take back control.

The fourth stage is the most dangerous stage. They can usually fly for ten minutes and when they make a mistake they are usually capable of correcting the mistake themselves. I stress the word usually. What happened in my case was that my trainee made a mistake, I allowed him the time to correct it but he made a horlicks of the correction, I gave him a little more time, but before I could regain control the model had smashed itself into the ground. Fortunately the mighty, much-loved Enya seemed to be undamaged.

The fifth stage by the way, is when they have passed a nationally recognised certificate of competence such as the British A Certificate or the French Brevet A. You can kiss them good bye then. They can fly on their own!

Sooooooooo about six years ago the wing departed from my Telemaster 40. The fuselage turned itself into a lawn dart and was only any good for firewood! crying For Christmas I treated myself to a pair of floats. They turned out to be too small for my Senior Telemaster so I decided to build another Telemaster 40, as I still have some structurally sound wings and I plan to build it so that it may be flown from either floats or wheels and it be used in training mode as a replacement for the Boomerang.

I have a number of unemployed fourstrokes including three Laser 70s, sleeping in their boxes. Initially I thought of fitting one of those to the T40 but then I thought that if I had a repetition of the Boomerang event, one of my beloved Lasers could be wrecked!

A few years ago I bought an Enya 45 and two OS 40s at a swap meet for 5€ (£4.28 Sterling or $5.57 US). I decided to fit one of those to the Telemaster 40 and managed to get two of them going on the test stand earlier this morning. They ran very well but they require a strap on silencer. I fitted a BCM silencer but it didn't and oh the noise! sad

Doesn't anybody make a decent strap-on silencer anymore? frown

Thread: Forum members' new models: Let's see them.
12/01/2020 18:17:18

I have never liked control line models but that is a beautiful model!

Thread: Paint masks& markings
12/01/2020 13:21:02
Posted by Tomtom39 on 12/01/2020 12:08:02:

I understand Tim Calvert has given up.

Yes he has. It's a pity because I used him a lot.

fished job 1.jpg

baron apres premier vol (2).jpgj60 in winter.jpg

Edited By David Davis on 12/01/2020 13:22:02

Thread: If I fit floats to my Senior Telemaster will I need a more powerful engine?
11/01/2020 17:17:50

You are right Alan, I used to import Telemaster kits from America and I have flown Telemasters with four, six and eight-foot wingspans, but when I first set up the business, I initially built a four-foot Mini Telemaster and others built the rest of the range including Samantha who assembled the ARTF Senior Telemaster under my supervision. A bloke called Richard, who sometimes posts on here under the soubriquet, "Sparks" because he's an electronics engineer, built the Telemaster 40 and I've no idea where the cg was. Here we are in the picture below.

Team Telemaster

What I DO remember however, was that it was the nicest model to fly out of the entire Telemaster range.

I'll probably go with a cg a little in front of the marked position on the plan.

Edited By David Davis on 11/01/2020 17:19:41

Thread: What size model?
11/01/2020 11:40:53

I once knew a man who drove a Peugeot 205 GTi and who managed to cram a Precedent Stampe biplane into it.He put the transmitter and a bottle of petrol into the two cockpits and it really didn't take him long to assemble it once he'd got to the flying field!

Thread: The Big Guff.
11/01/2020 09:02:37

The construction of the Big Guff continues. I have covered the tail surfaces in Red and Antique Solartex. I intend to cover the fuselage too and to move both of them into the guest bedroom while I attend to smaller models requiring servicing or repair before the flying season starts in earnest. The tailplane is over a yard wide (94cms) and could have been easily damaged in storage in its uncovered state. Building the tailplane with its "eggbox" system of construction has been good practice for the wings which are built in a similar way. The assembly weighs 8.5 oza or 241 grammes. I have not yet glued the hinges in place nor the fin to the tailplane.

Picture below. I don't know why it is on its side but it's not the only one. Mods can we do something about this?

tail surfaces covered.jpg

francois and his prize.jpg

Thread: If I fit floats to my Senior Telemaster will I need a more powerful engine?
11/01/2020 08:11:56

The cg marked on my Telemster 40 plan is 4.5" from the leading edge or 37.5% of the 12" chord. This seems rather too far back to me. The model does feature a lifting tailplane so perhaps that has something to do with matters.

Would you recommend moving the cg forward to a more normal 30-33% of the chord on the landplane version before moving it even further forward when it is fitted with floats? If I were to fit a Laser 70 to it this could easily be achieved!

10/01/2020 11:55:29
Posted by Alan Gorham_ on 10/01/2020 09:45:00:

David, based on the information you've given about the floats in your previous post this morning, I would urge you to check one more dimension against your proposed fuselage....

If you lay the fuselage plan out and lay the float plan out in the "installed" position ie with the step in relation to the CG as per the manufacturers instructions, do the noses of the floats stick out ahead of the prop by at least half the proposed prop diameter?

If they do not you will find the model hard to get up on the plane and in the worst case, opening the throttle will make the floats want to dig into the water, pulling the models nose down. Now is the time to resolve that question!

Having laid the float over the plan I've found that the nose of the float sticks out 5.5 inches ahead of the prop so if I use an 11" prop I should be alright.

That said the cg marked on the plan is 4.5 inches back from the leading edge of the wing on a 12" chord. I make that 37.5% of the wing chord. I can't be sure any longer as the model has crashed and somebody else built the model for me in the first place but I think that the model balance on the spars. In other words the cg was at 3" back from the leading edge, 25% of the chord.

PS. Alan, check out the size of the rudder in my earlier post this morning showing my Telemaster 40 in flight. It's rather small even for a trainer. I think I'll enlarge it 50%.

Edited By David Davis on 10/01/2020 12:05:41

10/01/2020 05:43:56

Thank you for all of your advice gentlemen.

The floats came with instructions on how to mount the floats e.g., mount the step at the centre of gravity, with the top of the floats level, the wing incidence should be 1,5 degrees,floats should be parallel to the centre line of the fuselage and lead should be placed at the front of the floats to being the cg 9-10mm in front of the manufacturer's recommended position.

Given that I've already bought the floats, and given that the fuselage of the model should be 25% longer than the length of the floats, I am considering building another Telemaster 40 fuselage and tailplane as the length of its fuselage is 45" (114 cms) which is about right for these floats. As you can see in my previous post, the tailplane survived the crash but two house moves later it has disappeared.

I am wondering whether to fit an electric motor as per my original Telemaster 40, or whether to fit a four stroke engine. I have a few homeless 48-70 four strokes which would fit.

Rapsody in Blue!

.

09/01/2020 14:06:54

Well I've gone and bit the bullet and I've bought a set of ready-made floats. I thought I'd prepare a model for floats over the winter. The floats were advertised on the internet advertised as being suitable for models weighing up to 5kgs or 11lbs. I had intended to fit them either to my Senior Telemaster or perhaps to my WOT 4 XL. When they arrived they turned out to be VQ Model 635 2481 Floats intended for a 40-46 size model.

I consulted the book "Radio Control Airplane Workshop Secrets" and was advised that the length of the floats should be 75% of the length of the fuselage. As the floats are 92cms long or almost exactly 36" then the maximum fuselage length should be 115cms or 48".

My Senior Telemaster, with flaps, Barn Door ailerons, spruce spars and a glider tow release weighs 12lbs 4ozs (5.5kgs) and its fuselage length is 1.5 metres or 60" so it fails to meet the criteria for both the weight or the fuselage length.

Senior Telemaster

My WOT 4 XL has a fuselage of only 48" but it is powered by a 150 V twin fourstroke. In the picture it has an Enya 120 FS installed. The problem with the WOT 4 XL is that underside of the fuselage is far from flat which may make the installation of floats difficult.

wot 4 xl 1.jpg

I have a vintage Uproar, a replica of the model which placed second in the European Airobatics Championships in 1959. It has a flat fuselage bottom but it only has a tiny rudder so whether that would be suitable as the basis for a float plane I don't know.

nearly there. (2).jpg



Otherwise I could build a Telemaster 40 fuselage and tailplane. I still have the wing. It broke off one day when I was demonstrating the model to a potential buyer! That'll teach me!

rip t40 (1).jpg

Or I could buy an ARTF 40-46 size trainer and convert that.

What are your views?

Thread: Bob Wright's HM 18 Flying Flea as modified by Abbott Baynes. 53.5" wingspan.
03/01/2020 18:39:11

Thank you Max. I am only going on what is printed on the plan. I read elsewhere that the HM 18 had an enclosed cockpit as in your picture. My plan shows an open cockpit. I'm not sure how I'm going to finish it but one thing's for sure, I won't be entering it into any scale competitions!wink

 

PS. I've just bought a copy of the December 1992 Radio Modeller on eBay so maybe the build article will enlighten us.

Edited By David Davis on 03/01/2020 18:45:25

03/01/2020 16:24:25
Posted by Bob Cotsford on 03/01/2020 16:13:26:

Let's see if this pdf link works, it says the early Fleas had a sharp LE which on later versions was changed to the rounder LE we would expect to see. Is the rear wing LE a square section set on edge to give the pointy LE? Is there any clue to the front wing section on the side elevation?

All of the ribs on both wings feature a 1/4" square section leading edge set on the side to give a pointy leading edge.

03/01/2020 16:11:17
Posted by J D 8 on 03/01/2020 16:02:05:

I have never heard or seen square leading edge's only trailing edge's being left square, something to do with better precision with aerobatic types.

The leading edges are made from 1/4" square balsa turned on the side so that they present a sharp edge to the airflow. A diamond shape in cross section.

Martian, I was at Greenacres when Ian Redshaw flew the Bertie Bassett Flying Flea and I got to talk to him.

Edited By David Davis on 03/01/2020 16:14:04

03/01/2020 13:35:09

In 1997 my best friend and former lead guitarist Micheal Harker was diagnosed with leukaemia. We played our last gig together on New Year's Eve 1999 and within two years he was dead. Michael had had a private pilot's licence but had never built a model. As he became less and less fit he asked me to suggest a suitable radio controlled model which he could build and fly. I suggested the usual suspects but he wanted something more challenging and chose Bob Wright's 1/5 scale HM18 Flying Flea, as modified by Abbott Baynes. This aircraft is unusual in that instead of the elevator operating in the normal manner, the entire tailplane is fixed. The mainplane pivots to provide pitch control. I flew one at Cocklebarrow once and it flew very nicely but I handed it back to the owner for him to land it!

Searching through my stuff I discovered that Michael had kept the plan, a December 1992 Radio Modeller publication, and he had also cut out most of the components. He had even made up a template for the curved wing spars. Being a magazine free-plan, it's not that easy to follow; red ink is used for the starboard wing and blue ink for the port wing but maybe I'll build it in Michael's memory. I've got a few little four-strokes sculling about not doing anything.

However, on studying the plan, as we do, I spotted the following instruction, "NOTE: L.E'S ARE NOT ROUNDED." Then there is an arrow pointing to the leading edge of the tailplane.

I have a few questions for people with superior aerodynamic knowledge.

I learned at my mother's knee that if the leading edges are not rounded the model's propensity to stall is increased, so why is there this instruction on this plan?

Is it because it is a tandem wing aircraft?

Does this instruction apply only to the the tailplane or should the leading edges of the wing be left sharp too?

Anyone have a copy of the magazine? December 1992 Radio Modeller? I would willingly pay for a photocopy of the build article or for the complete magazine.

Thread: Uploading pics. to album
03/01/2020 12:59:33

Eric, go to the brown-red line at the top of the page marked "Settings," "Inbox," "Friends," "Albums" etc and click on "Albums."

If you want to create a new album, click on "Create A Photo Album." Then give the album a name and description, though I believe the description is optional. Then you click on "Create Album."

Having created the album you then click on "Edit Photos." Then click on "Add More Photos." You can then browse the pictures stored on your computer and select up to five at a time. Having made your selection you click on "Upload" and the pictures will be put into your album. This might take some time. Once they have been uploaded click on "Save Changes" and all should be well.

If you want to add pictures to an existing album, click on the album, then click on "Edit Pictures," then "Add more Pictures" and continue as above.

Best of luck. We'd all be interested to see your models.

Magazine Locator

Want the latest issue of RCM&E? Use our magazine locator link to find your nearest stockist!

Find RCM&E! 

Support Our Partners
Cambridge Gliding Club
Pepe Aircraft
Slec
Gliders Distribution
CML
Wings & Wheels 2019
electricwingman 2017
Advertise With Us
Sarik
Latest "For Sale" Ads
Do you use a throttle kill switch?
Q: This refers to electric-powered models but do you use a throttle kill switch?

 Yes
 No
 Sometimes
 Rarely

Latest Reviews
Digital Back Issues

RCM&E Digital Back Issues

Contact us

Contact us