Here is a list of all the postings David Pearce 4 has made in our forums. Click on a thread name to jump to the thread.
|Thread: Sign of the times - funnies|
The people of Dubai just don't like the Flintstones.
But the people of Abu Dhabi do!
|Thread: Seagull Challenger - First kit Build - First IC|
I have the artf version of the Challenger. It's a good choice, very docile without any bad habits. But fast enough for some fun.
|Thread: Seagull Challenger Sport LW C of G|
Hi Snorbitz, I have the artf version and was surprised at the 60mm recommendation for c of g. It looked so far forward of the main spar and from where you would expect it to be. So I did my own calculations which placed it at 75mm from leading edge. It flies very well with this c of g and is responsive and stable. I've had many successful flights with it.
|Thread: C of G Question|
As I asked the question I thought I'd give an update. I've followed the advice and have been moving the C of G slowly back.
Now all the nose weight is gone and I moved the battery back and the C of G is 82mm instead of the recommended 60mm. She now takes off easier and flies well with no vices.
I've learnt something from this, thanks for all your help.
I'll read that with interest.
That's 98mm which would be about a third of the chord. Perhaps too far but it does show that there's some way to go.
Thanks for that John. I should have mentioned, it's 4S electric, although that may not effect your advice. So you recommend I remove more nose weight, a little at a time, until it flies without up trim, or gets twitchy?
I have a Seagull Challenger ARTF which I have had 4 trimming flights with. When the build was complete I balanced to the recommended C of G of 60mm from the leading edge. Two things struck me, one was that it required about 100g of nose weight to achieve this and the other was that, with a chord of 270mm, 60mm was only 22% of chord. It looked too far forward and was certainly outside the normal position.
Other users on another forum said 70mm worked and when I did a calculation on a C of G app it came out as 72mm. So my test flights have been removing most of the weights to move it back bit by bit. I now have it at 72mm but find I have two conflicting attributes:
Otherwise it flies well with none of the twitchiness that being tail heavy usually causes. I have no down thrust or side thrust as none is recommended in the instructions.
I’d be grateful for any advice. I can fly it with permanent up trim but I am wondering if there’s another answer?
|Thread: What effect does a large cowl have on the efficiency of propeller?|
Thank you all for your input.
I agree more testing and measuring is required. I'd rather get it right the first time so, if there's any doubts, I may well go for a lower KV motor.
I have a Great Planes Mr Mulligan ARTF. The recommended motor is Rimfire 32 with 800Kv and a 12” x 8” prop. That’s a rather expensive, and rare, motor and I’m hoping to use a motor I already own. This is a 900Kv motor which delivers the required 800+ watts using an 11” x 5.5” prop.
My question is; will the large fat cowl have an effect on the power and would I be better off buying a new motor, of lower Kv, to swing a large diameter prop? Is that 1” important? (Fitting a larger prop to my existing motor would raise the current too much.)
Your advice would be appreciated.
Edited By David Pearce 4 on 02/07/2019 10:33:14
|Thread: Ripmax ARTF stocks|
I was just looking around at my favourite retailers and noticed that there are very few Ripmax ARTFs in stock, particularly WOT4s.
Is this a worry or just temporary?
|Thread: New EDF Mini Jets- Jet Provost & Folland Gnat|
Apart from looking great, what impresses me most Tony is that you've designed an EDF model with a duration of 7-8 minutes. Against typical EDF models, including foamies, that's quite an achievement.
|Thread: Electrifying a WOT4 Pro ARTF|
Thank you John for your helpful reply. It's not too late either as, as often happens, I got sidelined into something else. But I am still keen to get another Wot4, there's nothing better for sport flying, towing streamers etc.
I was also pleased that someone knew the version I was going on about! I'm encouraged by your comments and I think the Pro version is worth the conversion work. On a maximum of 4000mah lipo it must offer longer flight times than the other version.
I find it odd that Ripmax chose to offer a lightened version for ic only. An electric version seems an obvious choice.
Edited By David Pearce 4 on 29/03/2019 18:31:22
|Thread: RIZLA +|
Well Gary, as I'm an electric only flyer I'd prefer a Rizla but the original size as I prefer to stick to 3S or 4S.
Thank you KC. I've identified the RCME issue with the Swamp Rat plan, should be able to get it on eBay. Cheers
Do I take it that neither the Rizla or the Swamp Rat are available as plans then?
I always liked the Rizla. Did it, or its smaller version, ever get published as a plan?
Edited By David Pearce 4 on 17/02/2019 18:05:18
|Thread: Removing sticky acetates from new ARTFs|
I guess the advantage of Googone over petrol or lighter fuel is that your wife walks in and says "hmmm, nice smell" rather than "what is that smell?" Handy when you choose to work in the kitchen
I tried using heat on a small sticker and it came away without much trouble. It left a residue of glue so I used some 'Googone', which is made for removing cellotape glue etc, and the end was result was excellent. I then experimented with just using a drop of Googone under the sticker edge and no heat. This worked well and using a rolling action the sticker came away leaving less residue. Cleaning up with Googone and kitchen roll taking care not to dent the covering.
So Googone works without heat but I guess different combinations of covering material and stickers may need different solutions. So always test first.
I now have an airframe clear of stickers awaiting my own markings.
Thanks Ken, sounds simple enough, I'll give that a try.
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