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EvilC57

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Posts posted by EvilC57

  1. In my post entitled 'Black 5 twin IC from Sarik Hobbies - Anyone Know it?' here - which I'm planning to build, I wrote about the Black 5 having a bit of an ugly slab-sided fuselage.

    This being the case, I've located a plan for a similar twin IC model called Fifty Caliber, by Dick Sarpolus. This has a much prettier fuselage, which I'm hoping to be able to re-scale & redraw, and transplant onto the Black 5 plan instead.

    My question regards vertical positioning of the wing: The Black 5 (the one with the ugly fus) was designed as a tail dragger, with the wing positioned half way up the height of the fuselage. The Fifty Caliber (the pretty one) was designed with a tricycle undercarriage, and the wing is nearer the bottom of the fus - albeit with the usual small box fairing underneath.

    In other words, what is the vertical positioning of the wing in the fuselage a function of? If you look at (for instance) a DC3, it's a tail dragger, yet the wing is underneath the fus.

    Presumably the tail needs to be kept up clear of any turbulence coming off the wing, but other than that is wing vertical positioning important?

    Edited By EvilC57 on 19/12/2019 16:43:15

    Edited By EvilC57 on 19/12/2019 16:44:55

  2. Posted by Steve J on 14/12/2019 19:01:38:
    Posted by Gary Manuel on 14/12/2019 16:03:47:
    Posted by Steve J on 14/12/2019 13:59:32:
    Posted by Gary Manuel on 14/12/2019 13:34:21:

    How do you know Steve?

    Somebody did an FoI request and published the results.

    Interesting to see how it is after a full year.

    The number in March would be interesting as it would include the people who have registered via the associations.

    Anyway, it's looking like the associations members are very much a minority of drone and model aircraft flyers .

    Bet it’s not 170,000 as the CAA originally thought though frown.

  3. As part of the ongoing upgrade of all my computers to Windows 10 in light of the forthcoming demise of Windows 7, I've been looking into an update of the Logview Studio V1 charting software I used to use with my CellLog 8S battery monitor & logger.

    It seems there is now a V2 of this, which is just called LogView. I've now installed this, and apart from the fact that bits of it are still in German even if you choose English language during installation, it strikes me that it's still in need of development as there are bits that don't seem to work properly.

    Given that it's obviously been developed on a shoestring (as they ask for donations on the webstite), does anyone know of any similar, but more highly developed software which will do the job better?

    The CellLog is still being sold (as of Dec 2019), so I'm surprised that the software Junsi recommend to use with it hasn't been better developed.

    Edited By EvilC57 on 14/12/2019 17:57:28

    Edited By EvilC57 on 14/12/2019 17:58:37

  4. It wouldn't surprise me at all if there aren't vast swathes of people (drone fliers included) who know nothing of the CAA, BMFA or any regulations. As Bob Cotsford said above, many people seem to walk around in their own self-conatined little worlds these days - headphones on, or glued to their smartphones.

    This was bought home to me on the local TV news recently when a university lecturer was being interviewed about the varying interest of her students with politics (in relation to recent events). She said they varied, from those who were interested and active, to those who apparently said "What's a general election?", when she tried to engage them on the subject. And she instisted she wasn't joking!

    Edited By EvilC57 on 14/12/2019 16:23:25

  5. Yes I guess 80FS is outside the 50-70FS recommended by the Black 5 designer - the engine outlines on the plan are described as 'Laser 50/70'.

    As for the RCV 58s; you are correct, they're not especially powerful. I know this because I did a 'real world' tachometer comparison between one of my RCV58s and an OS 46AX on the test bench. Using the same 12x6 APC prop in both engines (within minutes of each other, so the atmospheric conditions were identical), the OS gave 500RPM more at full throttle than the RCV. So the RCV probably only produces about as much power as a good 40-size 2-stroke.

    Edited By EvilC57 on 15/10/2019 10:53:53

  6. Posted by Phil B on 14/10/2019 20:24:04:

    That's an interesting one. Please keep us updated. I fancy a twin trainer for 2 46s or 80FS. Would it do? I have a Dale Tattum plan on the go - Corben Super Ace 60 inch Laser 45. Lots of inaccuracies in the plan. I hope yours is better.

    Hi Phil, the plan says it's suitable for two 50-70 size 4-strokes, so you might be able to squeeze a couple of 80FSs in.

    I'd noticed a couple of omissions already. He's forgotten to include any details of for the main undercarriage legs (although I'm sure I can come up with something suitable), and there are one or two parts which are drawn, but have no labelling as to what they're for or where they fit. All part of the challenge of building something unusual I guess.

    And I guess more anomalies will crawl out of the woodword once I actually start building.

    Something else to finish first though, so I doubt I'll start this one until well into winter.

  7. I recently acquired plans from Sarik Hobbies for a twin IC model called Black 5, designed by Dale Tattam. Unusually for plans from Sarik (or formerly Traplet), there is no build article to accompany them. Being an experienced builder, I don’t particularly need this for the 'build instructions’, however I would like to know a bit more about the background to the model. The fuselage has a particularly angular, rather ugly, slab-sided design, and I would like to have known the rationale behind this.

    Does anyone know (or has built) this model, where/when or which magazine it first appeared in; or indeed, anything about Dale Tattam?

    My reason for wanting to build such an enigmatic model is that I have two RCV58-CD 4-strokes which are homeless at the moment, and they’re exactly the right size to go into it.

    black 5.jpg

    Edited By EvilC57 on 14/10/2019 16:02:54

  8. Right; Just for the record I’ve now discovered a way to switch in independent throttle control when needed.

    I asked a clever chap on our field who flies a twin engined job whether his throttle servos are on a Y-lead, or independent. He uses separate servos with a couple of mixes in his Tx, and kindly sent me the .SPM file which achieves this.

    This is how it’s done using a 1st generation DX8 and 8 Channel receiver (AR8000):

    Mix 1
    THR > AX3
    Rate: -100%
    -100%
    Offset: 0%
    Trim: Inh
    Sw: Gear 0

    Mix 2
    AX3 > THR
    Rate: -100%
    -100%
    Offset: 0%
    Trim: Inh
    Sw: Gear 0

    These two mixes mix Throttle (Ch1) to Aux 3 (Ch8), and Aux 3 back to the Throttle, and have the effect when enabled (Gear switch down), of synchronising the servo movements on both channels for normal flight. But allowing independent movement with the Gear switch up.

    In use this means that with the Gear switch UP you can start one engine and get it running while using the throttle stick to control it, then leave it idling while you start the other engine, and control it from the Aux 3 knob.

    When you’re ready, setting the Gear switch DOWN brings both engines under control of the throttle stick as usual.

    Note that you need to keep the Aux 3 knob in the centre of it’s rotation (where it beeps as it goes through centre) for normal flight.

    Note also that you also need to bind the Rx in Preset Failsafe mode rather than Hold Last Position, to ensure that the slave (Aux 3) channel also returns to closed throttle position on failsafe operation.

    Using an 8 channel Rx also leaves Ch2 and Ch6 both available if you want separate aileron servos.

    I’ve tried all this so far with a battery, receiver and two servos on the bench, and it all seems to work as described (I haven’t started building the target model yet).

    The chap who gave me this setup did say that if he were to get a dead engine in flight, he could switch the mix out, operate the throttle and see whether the remaining engine responds of not, from that he reckoned (knowing which engine was on the primary throttle channel) he could tell which one had cut - and put the correct rudder offset in accordingly. I suspect you would be lucky to achieve this in reality! However, it seems like a useful facility for ground running.

  9. I find thin cyano to be particularly dangerous, the way it runs around joints and often seems to find my fingers.

    Makes 'er indoors laugh sometimes when I go indoors with a section of model firmly attached to my fingers, or two fingers stuck together. I've found the thing is not to panic, and if it's something like a balsa model that can't be put under a warm tap, the sweat from your fingers and a bit of pulling, or the edge of a blunt knife seems to naturally loosen things up after about 20 minutes.

  10. Gen 1 unfortunately, so it's a non-starter for me then (excuse the pun).

    Starting primarily, as per Martin's OP. Also, as Martin says it allows you to practice engine out situations at a safe height before you are forced to when one cuts at an 'inconvenient' time.

  11. Posted by Martin Harris on 14/05/2019 15:49:13:

    Starting is where I find the ability to control the engines separately has some particular advantages. I have a 3 position switch which is set to idle starboard, idle port or full control on both.

    I start the port one first, check it for full throttle running and then switch control to the starboard engine, locking the port one to idle. I then start and check the starboard engine and then activate both throttles for a full power check. Having the running engine locked at idle means I can manipulate the throttle on the one I'm starting with no sudden surprises!

    I can also practice engine outs with the switch selecting either engine to idle.

    Having the ability to throttle back an engine can also add to the repertoire of an aerobatic twin...

    I'm afraid I don't know whether your transmitter is capable of this level of sophistication.

    I balance by ear - but I'm more concerned with reliable operation than getting the RPM to any particular figure and I can't remember the last time my tacho came out of my modelling box.

    Edited By Martin Harris on 14/05/2019 16:00:45

    I like the sound of this, has anybody ever set this method up using a DX8, and if so, how?

  12. Posted by cymaz on 23/12/2018 13:51:29:

    Couple of things on this..

    1. Anybody watched the Navy series about HMS DUNCAN on Channel 5? Apparently this ship can track a tennis ball sized object at great speed from 5 miles or so........so why didn’t the military track this object and follow it to home ?

    Yes it's true, the Samson radar on the Type 45 Destroyer can supposedly track small objects at Mach 3 out to a lot more than 5 miles (and up into space). It seems odd that the authorities don't have some means of tracking a drone that can only do 30mph or so. I guess it was the 'pop up' nature of the target that defeated them.

  13. You beat me to it cymaz. I was just about to say, the press treatment of this couple is like that of Christopher Jefferies, the landlord of Joanna Yeates, who was murdered in Bristol in 2010. Jefferies successfully bought prosecutions for libel against the Daily Mirror and the Sun. I guess this couple may want to pursue something similar.

  14. I gather that having had their pictures plastered all over the newspapers, the couple arrested have now been released without charge. Trial by media again sad.

    Even if he isn’t guilty though, it seems someone should have a word with this guy, as I gather he was often seen by neighbours flying his multi-rotor up and down the cul-de-sac where he lives. Obviously completely unaware of the words in the ANO about not flying near a built up area.

  15. Yes I saw that thread some tome ago thanks. To bring the info in it up to date:

    Robotbirds : As I said in my original post, I’ve bought some from there, but they told me they will no longer be stocking the larger sheet sizes.

    flyingwings.co.uk : Not on the website.

    epp-versand.de : Appear to have it, but they’re in Germany sad

    eppfoam.co.uk : Only list Depron on the website.

    rcfoam.com : List it, but all their white EPP is shown as Sold Out - and they’re in America frown

    epp540.com : Website seems not to exist anymore.

    I guess (short of having to ring around, and potentially end up driving to a model shop half way across the country) the answer is to call the traders going to the next shows (LMA Much Marcle?), and see if they'll be taking any.

  16. Leeds Model Shop, Flying Wings and others don't list EPP sheets at all on their websites as far as I can see, so it sounds as though maybe they have it in the shops but don't want the pain of having to package it for sending out by post. The guy at Robot Birds indicated that they and others would no longer be sending out large delicate sheets because of this.

    I can't remember whether I've seen EPP foam in trade tents at the shows around the UK recently. But I guess if it's available in future, it'll be to personal callers in the shops only.

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