Here is a list of all the postings Paul Johnson 4 has made in our forums. Click on a thread name to jump to the thread.
|Thread: Warbirds Replicas P51 Mustang|
Ron, true story once watched a delivery driver carry a large pile of boxes containing aircraft instruments. He couldn't see over the top and struggled to balance them all. Now they were all clearly marked FRAGILE, he dropped the topmost one onto the concrete floor. At this stage he couldn't bend to pick it up so preceeded to kick it all the way to stores....
Wish I had videoed it....
Edited By Paul Johnson 4 on 06/11/2020 17:42:50
I always as a preflight check move the control surfaces very slowly over their full range looking for any point which my jitter or pause.
It's usually when the feedback potentiometer in the servo which wears that causes an issue.
We can't stop all failures but can reduce them by some easy checks.
David just check them for for a minute or so. No need to add a couple of hrs running more important is to check them slowly for any dead spots.
Fms 9g servo at 6v is 1.8kg cm
David both my Spitfire, Bf109 and Yak all use 3.5kg servos and have been fine. The Yak has, until due to recent illness, had a lot of outings and has been fine.
Most 1400mm fms use servos of a lower kg.
A few tips to you who have manuals............ and LABELS!
The 1/16" balsa skin is a high quality SOFT material, being a lighter grade it will mark VERY easily with light fingernail pressure etc.
When you cut out the lower skin for the U/C make it your mission to add the balsa sheeting to stiffen the structure up.
Until this is done handle like eggs or you will find bits breaking off.
The soft balsa does contribute to a lighter finished model but until it is completed, covered etc you need to be careful.
Actually I was quite relieved.... he didn't send the boys..
Well well well so that's what's in the manual..... Well you lot won't need my help any more then!
Now where's the precious.....
No wonder I forget where I'm up to with you smutty lot....
Okay tomorrow will show the niffty little tool for adding the aileron hatch..
The Nerve racking bit.. cut out aileron and flap...
With the flap cut the top and then the bottom NOT right through from the top!!!!!!
Otherwise you will cut off the ribs.
DONT RUSH Take your time!!!!
next sheet the top front of the flap, the curved piece can be formed by wetting and GENTLY forming around a broom handle or similar and allowed to dry overnight as it is a small tight radius for 1/16" sheet.
Trimmed and mylar hinges fitted and pinned. Make the pins ONLY long enough to go through the 1/16" + mylar + 1/ 8" no longer especially near to where the torsion bar will be glued.
The flap was temporarily fitted to show why although fiddly we chose this method.
Fast forward..... wing underside sheeted.
Where's the other foot gone?
Probably searching for labels......
I hate you Butler.......
If the eagle eyed amongst you may have spotted, the torsion bar link has been left off. This is to allow you to remove the flap to complete it, cover , fit the hinges, and lastly add that bar. If you do not it will not allow you to remove the flap as it fouls R2.
Edited By Paul Johnson 4 on 03/11/2020 17:12:25
Edited By Paul Johnson 4 on 03/11/2020 17:18:57
Once you have marked the top sheet, time to sheet the bottom.
Check that there is not too much weight on the wing that may create a bow on it check the trailing edge with a long ruler to make sure.
At this point also measure the flap spar centres to aid in marking the skin for cutting.
Use YOUR measurements NOT MINE!
Okay I just checked back on my posts and realised that I had not mentioned that the flap spars should NOT be glued to each other
They are glued to each of their adjoining wing ribs only
Hey but that should be in the manual which you all have and have read BEFORE staring the build eh?
The next is something you need to take your time and get it as accurate as you can, please do not rush this.
You need to mark the cut lines for the top skin for both the aileron and flap.
Using a pin/needle push through between the aileron spars from the bottom through the top skin.
Do this at both ends of the aileron. With the Pin/Needles through turn the wing over onto a flat surface then using a long ruler as a guide on those pins draw a line on the top of the wing skin.
Next using the same method mark the cut line for the flap. This is as marked in the next picture. Please pay attention to where to mark.
Next construct the wing supporting Jigs
These fit under R1 and R10
Just had Graham and Sweep drop in..... apparently I've been slacking!!
So you balsa sniffers to date the build has gone very quickly, even without a manual, drawing and LABEL.
This has listed 10 sheets of 1/16 balsa, there is actually 11 in the box.
Even so please be frugal with it because should you damage any you will find it tight to complete the skinning, without trawling the model shops for any stock at the moment.
Laying the wing on it's stand off tabs on a flat surface start with the top and fit the first sheet in line with the main spar centre line. This will help the leading edge sheet when you come to add it.
Those damn feet again!
Now you may take the sheet to R1. I did not as I still had to sort out how I was going to utilise the early R1 with it's cut out.
I then worked towards the leading edge. Keep the trimmings!!
and finally the trailing edge. You will need to add a small piece of 1/16 as shown, I have written on it how big.
Trailing edge trimmed, leave a couple of mm extra to allow a nice tapered trailing edge.
Aww come on David is that all you done so far...
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