Chris Walby
-
Posts
2,814 -
Joined
-
Last visited
-
Days Won
3
Content Type
Profiles
Forums
Blogs
Gallery
Calendar
Downloads
Posts posted by Chris Walby
-
-
Sorry to head off at a tangent, but if you do have a dog of a model why not share it with the club instructor and great guy Dave!
I rest my case with selecting an unproven design, high wing loading and rearward C of G! None of this will be relevant with Richards designs, but just be carful what you wish for on the extras list 🙂
-
New day and less gloom and doom!
Ooorr don't get me on the subject of twins...and beside the fact that I have had more one engine/motor outs on electric than IC brings me to simple point of preparation and care + a good dose of plan B in readiness when it goes Pete Tong. IC twins I have are 3 Tiger Cats, Mossie and Dual Ace and the point there is NEVER take off unless everything is 100% as it will only get worse!
Not adverse to electric twins with OV 10, P38 (two!) BH Mossie, WooHoo, Grumpy Tiger Cub and the Focke Stick, so sticking to the subject the foam P38, OV 10, are interesting in this discussion along with the Grumpy Tiger Cub (balsa)
The foam P38 is a surprise as its 63 inch wingspan and AUW is just short of 3.7kg (over 8 lbs) and flies really well, but has that presence of don't push me or I might just bite back (if you do something silly). Three blade is nice and the 2 blade/motor upgrade is outstanding! hence why I have 2.
The OV 10 is another surprise, but with a twist its 55 inch and weighs more that the P38! with 2 x 4S4000 packs..and the twist? it has more wing area! Can't beat a thick wide plank of a wing!
Last is the Grumpy Tiger Cub and talking to Peter (the designer) it is very tolerant of single engine operation. 55 inch and AUW 2.5kg (5 1/2 lbs) and I can vouch for this as Mr dumb nuts repeatedly flew it with a duff 4S4000 causing one of the ESC to latch in LVC (the ESC continues but only up to 50% throttle), no drama and on one occasion carried on to the end of the 5 minute flight.
Now for a word of caution with a couple of bitter experiences, both of my doing. The first was the demise of my first BH Mossie, gear down, flaps 1/2 and slowed it up resulting in it dropping a wing at 25 ft. BH use to jig build these so they are very light, but when the UC hits the ground it rips the entire nacelle out of the wing, near total write off. The other was my Ta154 Moskito ic twin that turned out just plain heavy and a rather (massively understated) rearward C of G. Was it nice to fly...hell no and prop hanging a 18lb 80 inch warbird at 250ft due to loss of elevator authority was a very memorable moment!
With Richards help we did tame it a bit
Broken record time, build light without UC or flaps, dolly launch or hand chuck. Then once you have the hang of it add the weight and the expense if you want
-
1
-
-
Mr doom and gloom here!
On the EDF front (yes I would like one), but I think its a very emerging area of the hobby. There are some real winners out there mk1 Habu, but here is the catch as on tarmac they are a dream to get off the deck (4S3300/4000), but short grass and you have to peel it off, wet or long grass don't bother it will end in tears. Now these have fixed gear so look pants when flying around. If you had launch with the gear its very marginal, but without the wire gear (not even the weight of retracts) its a piece of cake. So what does that tell you about margins.
Now roll on the mk2 Habu...why does it have fixed gear, why is it 4S or 6S compatible, IMO because its all still very marginal. 4S off tarmac ok, off grass it has to be yanked off. 6S and grass and it gets off ok, but its hammering the battery in the process (yes I get LVC on the ESC, but with 1/2 to 3/4 the rest of the 5 minute flight is possible),
I have a SU47 (twin 70mm) that can kill a 6S4500 lipo in 2 min 15 sec and its so marginal flight performance its bike clips at all times. I has such aggressive cheat holes that with UC it actually sucks it to the deck on roll out...back the throttle of and it lifts off the ground...but not for long before its aggressive stall catches up! The most successful launch is to remove the retracts (still weighs 2.6kg) and hand launch with stabilisation/safe on. Its that marginal it just misses the ground but then it up to me then get a few circuits before belly landing!
IMO Arrows have cracked it, small and light models powered by 3S2200 and guess what...no retracts, no wire UC, no flaps and not even a rudder, why? because they know its all about power to weight.
I tried a FT kit that could be pusher or EDF and what was surprising was the loss of EDF performance once you add and induction and thrust tube + it wants to implode on full power! So something like an A10 is doable but its been done and expensive.
Not flown one but the HK Vampires are very popular and fly very well, what's the winning formula?
Looks like we are back to single engine WW2 fighters with popular (common) at one end of the spectrum or unpopular/ rarely modelled at the other end....or dolly launched twin... but people will want retracts, then flaps and wonder why the retracts come out of the wings on a rough grass strip!
-
1
-
-
9 minutes ago, Shaun Walsh said:
You may have problems with spares availability or the Gen 1 DX8.
The main reason IMO that DX8 gen 1's hold their price is that they will do both DSM2 and DSMX, the gen 2 will only do DXMX so less sought after.
Yes Spektrum don't do spares for a DX8 gen 1 but the only things than have gone wrong with mine is me damaging a switch of the aerial pivot breaking (non OEM ones available and work ok). If you don't want the risk or hassle then go for a gen 2. Firstly the aerial is fixed and secondly Logic RC will probably service/repair.
The second DX8 gen 1 I bought the chap had just had it serviced and had the receipt.
If you are budget driven, want a more user friendly menu, more relevant support (I understand Spektrum are still issuing firmware upgrades for the gen2) and spares then IMO go for a DX8 gen 2. One other risk is that there were a lot of DXM2's RX that were counterfeit so I can avoid that with a gen2
PS I had some serious issues with a DX8 gen 1 (both) with Lemon RX's 8 channel (two), but others didn't with lower channel counts
PPS as others have said, wait for a new in box, never been used one turns up...and avoid the punter that doesn't have a good reason for sale/has crashed his last 6 models due to TX failure (or dumb thumbs).
-
Mr Dinosaur here!
I still have mine and my son's DX8 gen 1's (silver), work perfectly well on DSM2 and DSMX of which there are plenty of DSM2 RX's as lots of people have moved on and the DX gen 2's will no operate DSM2 RX's. This is why DX8 gen 1 still hold their value. Of course being old tech then don't have the functionality to get the best out of the forward programming features of the modern RX's. Depends what you fly? and more importantly what you think you will be flying in a few years time?
DX8 gen 2 is a nice TX and has the forward programming functionality if you are panning on using stabilisation/safe.
IMO the biggest driver is what you want and how prepared you are to learn whatever system you intend to use, if you local club have experts in system Y then choosing system X is hard work, but then again their are people that have the time and enthusiasm to learn and just go it alone anyway.
I bit like GG says!
-
2 hours ago, GrumpyGnome said:
Possibly just the two of us.... I keep mentioning it, and the Whirlwind....
Make that 3 of us...just need to find another 35 buyers!
-
1
-
-
2 hours ago, Flying Squirrel said:
Fantastic, appreciate the advice. Mine has two 3s 2200s up front and balances around 90mm from F2, total weight is only just over 4lbs so didn't know whether to leave as is for the maiden or add weight up front.
IMHO add weight that you can take out of later and get the C of G to max 80mm. Maiden time is normally high workload so and until you have its measure and trimmed in you don't want something too lively!
A 3 way switch with elevator rates is a real benefit as if needed you can calm it down or not, but I think you will find the FW190 a very pleasant model to fly with no vices I have found.
PS When it comes to landing you should be able to slow it right up!
-
1
-
1
-
-
Drawing quotes 70mm, but its very tolerant and to save adding lead only to then remove it I maiden mine at 78mm and it was fine (might remove some more when I get around to finishing the model!
Ron has mentioned hos is as far back as 100mm (did say its very tolerant !) and the point there IMO is the elevator becomes progressively more effective as the C of G goes back so don't fly with massive elevator throws if the C of G is a long way back from 70mm conversely don't have little travel and C of G at 70mm.
I put a little up on my elevator...that I then had to remove, IMO set flat.
PS one of the advantages of a more rearward C of G is it will take off and land slower, handy for the dolly launch.
-
2
-
-
Two options, put the tank in the right position or put the engine in the right position.
Failure to adhere to either option 1 or 2 will result in sub optimal running and possibly a dead stick at the most at the most inconvenient time. Result..loss of model or injury, is that negligence as you knew it was not correct?
Looks ok to me!
Laser appreciation society view
-
1
-
-
Spec for the 100
Additional information
DISPLACEMENT BORE STROKE PRACTICAL RPM RANGE RECOMMENDED FULL POWER RPM RANGE RECOMMENDED PROPS WEIGHT -
I'll go along with a Mossie (can never have to many
SpitfiresMossies. Either built, unbuilt or needs rebuilding I can can count 5, but half a dozen sounds like a round number to me!Just an observation, but with all the Mossies getting the C of G forward enough is always a challenge. One BH Mossie I bought has larger than required motors, but the correct props, clever as the additional motor weight is about as far forward as possible bearing in mind the 4S5000 lipo is in the nose already (so you can't do a bomber version). All eth servos are very near C of G. Even putting lipos in the nacelles may be a challenge if UC is used.
My SG Mossie has 2 Laser 70's, everything else as far forward + extra weight up front to get the C of G and looking at the electric versions the lipo packs are well forward in the fuz. Not sure that's a good place to put a lot of weight if a hard landing takes place as it might break its back.
I an sure Richard can iron these challenges out as he has in the past with his other twins 🙂 ...should he accept the challange!
-
1
-
-
I must be really missing the point, but as its a pushrod engine if you really want to know, just take the head off and measure it? Its not like you will loose the valve timing.
IIRC the valve timing is not that extreme so you could fill the cylinder head with oil (not castor!) at TDC, then turn to BDC, fill and the difference is the swept volume.
If you can't be bothered with any of that then put it in a test stand and go through a few selected props, measure the RPM and compare with the Laser engine web site for the recommended prop for each engine (slightly more difficult for the obsolete engines, but do-able).
PS, what did the original have on as a prop MC1 (assuming it was propped correctly)?
-
1
-
-
From what I picked up from my visit to Buckminster scale comp and a few longish conversations with competitors/judges was:
- The competitor researches their model aircraft (they need to document this anyway) and what the fight characteristics and capabilities are.
- The competitor can choose from standard or manoeuvres of their choice, but still needs to be within the known capabilities of the aircraft modelled
- You have to display in front of the judges/flightline with an start & finish points, so no flying at yourself inverted and bunting it out!
- Its not so much about how complex or difficult the manoeuvres are but how well you fly it IMO
So if you fly a spitfire then everyone is an expert and knows what the full size is capable of, but if you fly something that is either very early (WW1) or so obscure no one apart from you knows what it is capable of then you are the expert (within reason of course).
PS Don't pick an aircraft to model/fly that is a known trouble maker or something that's very high workload as once it starts to go wrong it will unravel very quickly.
PPS the BMFA B test is good to practice with everything flown in one hit and on one battery (limits faffing around time!).
-
IMO There is no rule of thumb as its totally dependent on the the way you fly or more importantly how you use the throttle stick!
Perhaps flow up to 10 minutes with very gentle throttle stick use or...just leave it WOT plus prop hang it and it might be at low voltage cut off on the ESC in 3 minutes.
Set the timer for 3 min, land after the time has gone off and then measure the battery voltage/capacity. Then ease the timer out so you normally land with approx 35% that way if you have to go a go around or two you should not be be below 25% (IMHO anything below that reduces the life of the battery long term).
Other opinions will be as relevant as mine. 🙂
-
1
-
-
Playing catch up as having moved and retired in the last 2 weeks.
First batch batch will do me as I can test out the old building board in the new location 🙂
I'll pm you with the new address!
All looking very good there!
-
IMHO I would not use either. Technology has moved on.
Lipo's that I use as a flight packs as they get a harder life and if they can't support powered flight they go for recycling that way they are always good enough for RX duties.
Don't like cheap/unreliable switches so go for a switch/UBEC that has sufficient current rating to deal with a failed/jammed servo and not brown the RX out.
Better go and hide in a BatSafe box now! 😉
-
1
-
-
Busy travelling yesterday and was rewarded is deteriorating weather this morning and no FW190 maidens (can't really blame them!).
Two training flights and one with my WR FW190.
In blustery and strong easterly wind where models with gyros and high wingers were earning their keep, the FW190 was outstanding!
Die straight dolly take off followed with loops and rolls plus impeccable rock steady handling the flight characteristics it was an absolute pleasure to fly today. I did chicken out with the low cross wind passes, but some pulls into big loops and half rolls were a lot of fun!
Four minute flight with it mostly at WOT and I only used 32% of a 4S4000 lipo, so come better weather I should be able to loiter around for the other FW190's to form formation or drop in on its prey once its been spotted!
Better get on and finish the paint job...
-
3
-
-
My 2 pence worth and TBH UC despite the cost, weight and extra building gets my vote (but not tricycle) so Zero or Macchi 202 are preferred. TBH I'll go with the herd as non of them are twins and the likelihood of getting enough people to make it viable is low so I don't think that will happen anyway.
I need the building practice whatever it is...before I start on the WR back catalogue!
-
1
-
-
If replacing the aileron servo, then it would be worth doing both or you might find mixing different mfg's you end up with different control surface deflections.
-
1
-
-
14 minutes ago, Nigel Dell said:
I was sad to see that Jon has now left and Laser is shutting its doors, I too have an i200 reverse and in my pm with Jon was the first I heard of the modification on the board, sadly I have not had a chance to run mine and the model that was quickly available still needs covering due to a spate of ill health, thankfully improving, I am guessing no one has had a reply as yet so I will go straight to a letter to try and glean more info, do we know what the part is called that we are waiting for?
I had inlines on order from mid last year and in the end Jon offered me me single 155's so I went for them. As I understand the issue is of design vs manufacturing (all things are compromises) and some engines suffer with the issue and some don't.
Its not so much a part that can be swapped, but more a fundamental design and manufacturing decision. The redesign would involve a number of significant component changes, but as I said not all engines are affected. I guess you need to run it to see which side of the fence yours sits, if there is an issue then involve the Laser warranty sooner rather than later. Perhaps that is why they were sold as development engines, so that people ran them and then issues would come up and be resolved, a bit like the petrol engines some sold and very few ever run and little feedback to Jon so very difficult to know if its an issue or not.
-
2
-
-
14 minutes ago, Geoff Gardiner said:
My glue of choice at the moment is Titebond Original, which I believe is an aliphatic glue.
Are aliphatics any good with the brown paper covering method / heat reactivity, or will I need PVA?
Cheers.
Possibly, but its an expensive way of doing compared with PVA glue (when you buy 5L of trade stuff).
Oh and the other thing if its Tesco (other long rolls of brown paper are available) ..don't buy a couple extra rolls just in case...because you don't waste much in off cuts so it goes a very long way!
PS the brown paper stock I now have will out live me!
-
1
-
-
First field meeting of the Butcher Birds and with a discussion revolving around rates and C of G I think we can say we are getting quite close (apart from me and my colour scheme!.
John i having a few issues with the spinner as it seems to change its seating position differently each time the prop is removed.
Lets hope the bank holiday weather is going to be kind to us and we can get the remaining two in the air (dollies have all been finished), oh and I sort my paint work out!
-
6
-
-
Don't worry Bucksboy, wait until he sees mine as its the normally non photographed version of red 23...it would be easier to say what is right with it than what's wrong with it and in the spirit of stand in the next field scale I don't care!
When I am flying it and it is a very pleasant model to fly its that which counts!
-
1
-
-
Last visit to Laser Engines to collect the first and last production V 310 pair.
Thanks to Jon for the final push which just leaves me to do this pair justice in a suitable model (DH).
-
8
-
The Big Question ?
in Warbird kits
Posted
Hi, I concur and my point was that a good design shouts volumes like the WR FW190, P38, OV 10, and Grumpy Tiger Cub, but the things that you are not in control of like our build quality for example can turn beauty into a beast. The PZ Mosquito all be it quite a lot smaller was a super flyer before I sold it on so I think is doable, but I still think the way to go to give us all the best chance is dolly launch as it removes the chance of UC damage and gets rid of a load of weight....then at a later date do a UC upgrade pack if people want it.
It wasn't until very near the end of the Ta 154 build that I found out that the Ta154 has 25% less wing area compared with the same size DH98, I have the wood pack for it and one I'll make a lightweight version and give it another go!