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    How many layers of fibreglass

    Hi team, How many layers of fibreglass will I need to get enough strength in my custom-made wingtips? They are a standard hoerner shape for the Bearhawk Alpha wing, NACA 4412, depth about 10" and span about 15". I estimated they will see about 90N of lift each at 1.0g. Obviously I want to...
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    Stress analysis of a simple wing

    Is there a simple formula which one can use to analyse the stress within a simple wing, of constant chord, shape, and with zero twist or washout? Perhaps there is a simplified form of the Schrenk approximation which removes the form factors and rate of twist variables? I really just want to...
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    Belated post - Bearhawk in NZ

    In case anyone was interested... Rather than re-post everything, here is a link to what we've been doing to make the most of our brand new Bearhawk, first of type to New Zealand: Bearhawk in the backcountry - Bearhawk Forums Thanks to everyone who proffered me advice over the year and a half...
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    Fasted build time (hrs) 4 seat aircraft?

    What are the fastest build-time (hours to construct) aircraft kit-sets on the market, with a real-world four seat capacity?
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    What are the fastest kitset or commonly homebuild piston engine designs?

    Just an interesting thought I've been mulling over, I guess these would be the commonly built racers for Joe public (when he can afford it) - some wild one-off design isn't really relevent to this post. But I am talking about cruise speed, rather than Vne. Some designs that come to mind: I...
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    Painting technique

    Hey all, So I am looking for some after-the-fact advice on painting technique, I've had a problem with painting yellow. Polytone paint by Polyfibre. The problem is, the colour of finish I get changed depending on the aspect I'm painting. Let me explain: I start with an even white basecoat...
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    Aluminium cowling doors - chafe tape to save paint?

    So I have noticed that paint doesnt hold up well to aluminium cowling doors being opened and shut against it. I figure with vibration the pressure from the camlock fasteners will cause to cowl doors to wear all the paint off the bottom cowl. I was thinking about putting on some chafe tape. Does...
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    Photos from the Bearhawk build

    So! I am moving her to the airport in two weeks time, after 14 months and 1600 hours building, not to mention probably another 500hrs research plus 300hrs on a full documentation suite (POH, AMM, Test Flight Plan, Build Log, etc.) It's fair to say I am a bit tired, and still very poor, but...
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    Polyfibre Aerothane and Ranthane - what's the difference?

    Practically in terms of the qualities of the resulting paint job, and difficulty to apply the paint, are there any significant differences between these two paint systems? How much more durable are these polyurethanes compared to the one-part Polytone? Thanks for your advice.
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    Two-part paint for "semi-rigid" surfaces

    Will two-part epoxy primer and paint survive on a surface which is subject to some minor flexing, in this case the firewall? How about the boot cowling inside the windshield?
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    Heat tightening fabric (Polyfibre) - question

    Hey, So I have been through the Polyfibre manual and I can't see an answer to this one. When you do the final tighten on the fabric, at 350*F, is it normal to smell a little bit of "plastic" melting odor at first? I had just calibrated my iron and the fabric didn't seem to relax, so I don't...
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    What sized battery cable did you use?

    Hey all, I am interested to hear what sized battery cable you are using? I am installing a Skytech Lightweight starter motor, which is of course the largest instantaneous demand on the battery cable. I emailed Skytech, and seemingly got a reply from the "GM" there (which was surprising) who...
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    Making your Cessna-style windscreen watertight

    How do you normally go about making a clean and removable installation of a watertight windscreen? I have been told first hand that your avionics are at risk if no water-sealing is used. Sure, there is nothing to stop you just injecting a bunch of silicone or caulk around the edges, but that...
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    Are you a pilot and/or a homebuilder?

    It would be interesting to see what the breakdown of the people who participate on this forum is like, so I thought I'd try set up a poll. Hope I did this right!
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    Wiring Garmin 296 power supply to avionics bus

    Hey - can anyone offer advice on how to do this? I have a Garmin 296 which I want to wire into my aircraft power supply (it will never leave the aircraft) and also into my PFD. I dont know where to get any connectors purpose-built, and I dont have the ones which came with the GPS except the...
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    Where did you fly today?

    An idea shamelessly stolen from another forum, but let's see if it takes off here. A thread to post pictures and reports of any flying you might have done recently. No need for it to be limited to homebuilt and experimental aircraft - it's all good to share! So, go on, lets see em! :grin:
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    A good control for cowl flaps?

    Hey all, Does anyone know of a good cowl flap control you can get? I'm thinking similar to a Cessna etc which gives you some locking force against the air pressure of the flap and vibration. I've looked at some push-button locking controls, but I think their "10lb" locking force is...
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    Are landing lights worthwhile?

    Hey homebuilders, So it's come time for me to decide about landing lights. The heart of my question is, are they actually useful for a VFR pilot who's landing in poor light conditions (twilight), in case a VFR pilot gets caught out later than planned? We've postponed the idea of making an IFR...
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    How much to flare fuel lines / brake lines

    Hey all, I happen to be following Taiser's CH750 build thread, which is brilliant, and noticed some pretty large flares on his pitot tube lines. Obviously this isn't a pressure application so it'll be sweet as, but it got me thinking. How much is the ideal amount to flare a tube end to get...
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    Horisontal Stabiliser Angle of Incidence

    Hey all, Been such a long time since my days of study that I can't remember how to do this, can you help: I am putting ribs on the tail of my Bearhawk, to change the horisontal stabiliser's shape from a flat Maule-style stabiliser, to a symetrical aerofoil shape. This is a standard "upgrade...