Here is a list of all the postings Graeme Evans has made in our forums. Click on a thread name to jump to the thread.
|Thread: Tucano power system chat|
quite right, but for that size of motor the 11.4A is either wrong, or isn't the max amps value... way too low.
The max amps for that size motor would usually be in the 30-50A region
Edited By Graeme Evans on 16/11/2012 20:04:33
|Thread: Mass Build 2013 The Shortlist - time to vote!|
Maybe the 70 ish inch recent free plan of that should have been on the list... probably not as simple a buld though
How frustrating... I'd have picked the tucano in a heartbeat... but I already built one, and although it's brilliant i'm happy with just the one of them. So my vote is for the Wizzza, but I will have to put wheels on it or it will get terrable gravel rash where I fly.
The tucano is a great plane though, I have removable wing and trike UC on mine, with about 400w power on a 2200 4s battery, flight times are easily 10 mins usually.
My Tucano is the black/yellow scheme, but although its the 'right' (aka scale) colours and its nice on the ground its also absolutely aweful to see in the sky... orientation is difficult (for me st least) with all that black.
if the tucano wins I'm sure there will be allsorts but, I hope to see some like this:
Edited By Graeme Evans on 18/10/2012 20:33:35
Edited By Graeme Evans on 18/10/2012 21:04:07
|Thread: Dynamic balance on props|
I know some props are pretty well balanced and for IC I would largely agree, though I do usually check the balance anyway. Afterall a 2stroke 90 engine shakes like hell anyway!
For electric howerver you usually end up spinning the same prop at similar RPM on half the size shaft in a model half the mass, then I find that even the brands you mention can be tweaked with noticible improvment in flight.
Wow... what a response.
While I do still think the dynamic balance as desribed in the article is not as others would decribe I am increasingly worried about the drilling of the the hub for balancing. I can well imagine some people getting carried away and having very little hub left.
PS: Sorry to Brian Winch if you read this I don't mean to be ungreatful for the effort surely taken writing quite a long an important article but I am seriously worried about drilling the prop hub directly as illustrated.
Edited By Graeme Evans on 19/09/2012 21:11:50
Just read the article "Question of balance" in the Autum 2012 special... and was confused by the desciption of dynamic balance, Brian describes it as "it must be in balance over their length, i.e. half way along the blade (for eg) they must be equal in weight" and goes on to describe balancing them in sections along the blade.
This is not my understanding of dynamic balance at all, infact the relative weight along the blade is a self canceling compnent of any balanceing system.
Car wheels are dynamically balanced but at no point are weights added at different distances from the centre, rather on the inside/outside as needed at various calculated positions.
It was my understanding that dynamic balance referred to the difference in weight of parts of the rotating object along the axis of rotation, not across it, easier to think of if you picture an axel... if you put a weight on the side of an axel and another identical weight opposite but further along the axel it would still be in balance laying across a simple prop balancer but if spun sufficiently would vibrate.
additionally in the same article suggests drilling many holes in the hub to remove weight... i really woudn't like to be near that at 14,000 rpm.
Is anyone else botherd by this ot is it just me?
|Thread: C of G on electric Conversion|
Thanks for everyone's help, I thought probably I was just overthinking. I'll just go with the CG on the plan with battery in and ready to fly and take it from there.
I am building a model from a plan that was written for IC, but I am going to fit it out electric. The model is a Cap21 (by Peter Miller) from an old free plan.
The CoG is clear on the plan but on IC the CoG is with no fuel, so the actual CoG will be infront to some degree.
Although the overall setup will be a little lighter than IC the battery, a 4s 3000mah pack, will be heavier than the fuel, so it wouldn't make sense to balance without the battery, infact it would probably be impossible.
Does anyone have any suggestions for selecting a CoG when converting IC to Electric? Should I just go with the plan... I know it will fly if I balance it as per the plan but i'm sure Peter Miller allowed for fuel in flight so maybe the ideal postion would be slightly forward of the mark on the plan?
My flying ability is distlicly average, and I don't want to find the CoG is right at the back of the limit and end up with a premature landing!
Edited By Graeme Evans on 11/06/2012 10:30:08
|Thread: Dear Santa I would like......|
Considering christmas usually means presents in boxes... and serious models won't fit in a under any tree I have kinda had my eye on this little bit of fun...
AT6 Funfighter - EPO 720mm (PNP)
(these are crazy fast)
|Thread: What Next review (3x low wing trainers)|
I was disappointed/surprised not to see a H9 Pulse XT 40 on the list.
I'm sure there would have been lots to choose from but still.
I loved mine and found it easy as a novice to fly but very capable. Infact I have struggled to find anything to live up to it since 'the accident' ... same engine requirements as your selected bunch and although practicality needs to be a priority for the novice... a whole lot prettier than at least two of the selected models too.
I'm certain Horizon would have supplied one for you.
Any reason it didn't make it? was it considered?
Edited By Graeme Evans on 19/10/2011 20:16:43
Edited By Graeme Evans on 19/10/2011 20:16:54
|Thread: Model suggestion as a Plan - small power glider possibly|
|Yeah, I did look at that, and it would fit the bill but I already have piles of balsa and £60+ is money I don't have|
I want to build a small electric model along the lines of a electric glider - but not for actually gliding. The World Models Sky Runner is an ARF along the lines I am thinking but somthing as small as a Multiplex Merlin would also fit the bill.... except I can't find a plan for a similar model...
Anyone know of anything I can get plans for along these lines? I would like a built up or foam/veneer wing, I have seen a couple of solid balsa wing plans but i'm not a fan of those.
|Thread: Ripmax WOT4 Mk2 ARTF chat|
without knowing the existing setting it's impossible to say, what you will have to do is get it running at FULL THROTTLE then screw in the main needle very slowly until the engine stops. This is your base line, just before it stopped would have been maximum power but you will want to undo around 1/4 to 1/2 turn for normal running, for running in you will want to be a little richer still, maybe 3/4 turn out from the point it stopped. Note that the main needle only the top end.
Leaning the engine out too early without running in properly will cause irreparable wear/damage to your new engine.
However I expect the instructions you have give you specific instructions for doing this, as the running in process is critical that it is done right from the very first flick. Not following these instructions will reduce the lifetime and reliability of your engine. If I recall Irvine's instructions are 3-4 mins on full power running a little rich on 20% oil fuel then a cooling off period, and repeat many times.
NO IDLE RUNNING AT THIS STAGE
With the throttle all the way back AND the throttle trim adjusted all the way down there must be NO GAP - at this setting your engine will NOT RUN.
If you don't do this you will not be stop the engine when you want to.
To run your engine the idle speed will be set by how far up you adjust your trim, but this is something that you will have to play with when you have your engine running.
Running in your engine is detailed in the information that came with, and it is imperative you follow these instructions, but you will require to be able to stop the engine on demand during this process.
To get your engine to run smoothly join and ask about at your local club, it takes hands on to fine tune your engine fuel mixture and it's something other members of your local club will be well practised at.
The only advice I can give as you are just starting out, don't adjust the low end fuel mixture. It's the screw in the lower end of the carb. The factory setting is close enough and until the engine is run in any changes could give you trouble.
be sure that you can close that throttle all the way, though the use of the throttle trim (or throttle cut button) is often used to close the final bit you will want to be able to stop your engine on demand.
if your Irvine is anything like mine the gap you're leaving open there would be a fast idle, it will run with a little less than that.
|personally I find the thinner hinges easier to install - and may I say an excellent choice of manual to refer to, I really like the Pulse XT 40|
Edited By Graeme Evans on 05/07/2010 18:56:42
I see someone mentioned the servo splines but the servo splines are a little more clever than was explained.
the splines are the grooves on the servo output shaft that the servo horn pushes down onto (and screw in the top) You will see usually that each arm on the control horn has a number on it, there is a reason for this... if you want your servo arm to stick straight out from the side of the servo when the servo is centred there is usually only one way round the horn can be.
Because there are a fixed number of splines (around 25) there are only 25 ish positions you can mount the horn in, but in one of them the the servo horns will be exactly square across the servo, this is by design, not chance.
Check on the horn which numbered arm you will be using for your setup.
The most common way you will learn this is when randomly cut 3 of 4 arms off your servo horn then realise that with the servo centred you can't get the horn on so it sticks out at exactly 90 degrees.
All of this can be compensated for on your transmitter afterwards by fiddling with the trim or by adjustment of the length of the push rod but it's nice to get things square in the first place.
There is another explanation here: http://www.rmfm.org/servo_arms.htm
|I guess they have changed the hardware pack since I built mine, I didn't have nuts on the control horns, just a plastic spreader pad that the self tapping screws screwed through into. still, howerver you cut them off you will probably want to file them a bit to prevent sharp corners|
|Thread: The May 2010 issue|
Just got my copy but the Habu review seems rather short, I was hoping for more than 1 page... though I suspect this to be related to the lack of pages 15-22 and 119-126.
|Thread: Ripmax WOT4 Mk2 ARTF chat|
|the kit version lists .40 - .90 4 stroke
The Artf isn't all that different, looks like Ripmax have been lazy not recommending 4 stroke engine sizes.
Want the latest issue of RCM&E? Use our magazine locator link to find your nearest stockist!