Here is a list of all the postings Piers Bowlan has made in our forums. Click on a thread name to jump to the thread.
|Thread: Revolver Pusher type Autogyro trainer|
This would appear to be the same from the HobbyKing EU warehouse.
|Thread: EPP Foam Availability|
I think this may clear up the confusion that exists sometimes. To paraphrase, Styrofoam is a closed cell blue foam made from extruded Polystyrene (XPS) and is a trade name, made by Dow Chemicals. Expanded Polystyrene, which is white, is sometimes incorrectly referred to as Styrofoam, notably in the US. Expanded Polystyrene is sold in sheets too in the building trade as Jablite.
I think Tosh is just researching foam generally Bob, as he is interested in Depron too.
Edited By Piers Bowlan on 05/08/2020 15:07:48
This appears to be extruded styrofoam and pretty good value too, don't know what the weight is like though. Doesn't say what minimum quantities for delivery are.
Yes the initials are correct. I think Polyolefin has an 'e' in it although spelling is not my strong point!
Phoenix Model Products used to produce a range of EPP models both powered and gliders but I believe they were discontinued when the EPP foam sheets became hard to source. Soar Ahead Sailplanes sell EPP flying wing kits made from EPP. You could try contacting Alan Head of SAS and ask him where he gets his from or alternatively ask him if you could buy some foam sheet from him.
EPP can be hotwire cut but the finish is not great and produces some pretty nasty fumes by all accounts.
As Denis says, buying some Depron foam is probably the easiest way to build a foam model. There have been some extremely impressive Depron model build blogs on this forum.
Edited By Piers Bowlan on 04/08/2020 15:33:57
Tosh, most foam models, whether from China or anywhere else, are usually made from Expended Polyolefin (EPO). It is much stronger than Expanded Polystyrene although slightly heavier. As far as I am aware it is not available in sheets, the models are moulded from it. Expanded Polypropylene is very tough but rather flexible and slightly rubbery so it is often reinforced with carbon fibre or glass strapping tape, as in the case of flying wings for instance. Car bumpers are often made with EPP incidentally. One of the drawbacks with EPP is getting a good finish on it although if lightweight filler is used and a laminating film covering, good results can be achieved as I found out recently. EPP is also heavier than EPO (or EPS) but a model made of it is almost indestructible! Multiplex (MPX) models are made from their 'Elapor' foam but as far as I can tell this is EPO again, although I could stand corrected.
I have heard that sheets of EPP can be hard to source. I did buy some in the USA once but not tried to get any in the UK.
Edited By Piers Bowlan on 04/08/2020 12:43:37
Be careful if spraying it on control surface linkages, not that one would normally, as it makes solarfilm sag and wrinkle. I don't know if it has that effect on all film but you don't want to find out the hard way!
|Thread: V tail question|
Grumman X-29 incidentally, for anyone interested. Another one for Tony Nijhuis to model
Edited By Piers Bowlan on 01/08/2020 17:37:53
Just a couple of wild theories to throw into the mix...
First I wondered if the fuselage near the tail could be twisting slightly when pulling out of a dive, although I understand that, like the wings, it too is reinforced with carbon fibre so probably unlikely. I had a Radian Pro XL that exhibited squirllly behaviour sometimes before I reinforced the aft fuselage with carbon. Obviously a totally different model to the excalibur I hasten to add.
Another possibility is that as the model has forward sweep this will have a tendency to wash-in the wing as it flexes when pulling out of a dive. If the amount of wash-in is only marginally asymmetric this will cause a roll away from the more washed-in wing. The wings are heavily reinforced with carbon probably to make them as rigid as possible. The full sized X-29 incidentally was built with very stiff wings because of it's extreme forward sweep.
It is only a theory - discuss. (I have my tin hat on!)
|Thread: Model Flying on Mars!|
Yes that is very interesting, particularly how they tested it on the Earth.
Back in 2015 Nasa were talking about releasing a Prandtl flying wing glider in the Martian atmosphere from a spacecraft. This was one of Al Bowers (Chief NASA Scientist-Ret.) pet projects. There are some details about it here, and also some interesting lectures by Al Bowers on You Tube if you are in to flying wings and you google him.
Edited By Piers Bowlan on 30/07/2020 19:21:43
|Thread: The State of Play|
Edited By Piers Bowlan on 30/07/2020 14:45:44
About 72in span might be not too large (therefore costly) for electric power and not too small/heavy for IC. Could one build a 72in span Beaufighter powered adequately by a pair of Laser 70s for example? What I am driving at is, is 72in span the 'sweet spot' regarding popularity, if a kit were produced by Richard? Obviously that will be too big for some and too small for others!
Another thought... How about designing the wings outboard of the engine nacelles removable to make transportation and assembly at the flying field very much easier.
Leccyflyer, I can't find a Beaufighter amongst Tony Nijhuis's designs on his website, perhaps he just never decided to kit it?
I too epoxy-glass the hull/fuselage, then paint. I film cover the wings but attempt to seal the edges with fuel proofer although mine are electric models. The inside of the fuselage I dope. The main problem is water ingress between the wing and fuselage. I have used thick foam tape and also silicone sealant but using clingfilm between the wing and fuselage while it dries to form a seal.
Receivers I wrap with clingfilm and mount them 'high' so that they don't stay submerged in any water that finds it's way into the bottom of the fuselage. ESCs I seal both ends with silicon but if they do get wet shake out the water and place in an airing cupboard or on a warm radiator to dry out. I have only done this when flying from fresh water lakes, sea water might be another matter!
|Thread: So what's happened to the August issue?|
Malcolm, I am sorry you have been having tough time of it one way and another. I don't make assumptions about anybody on the forum as none of us know of other members personal circumstances, I just read your post and it sounded like you were a bit piqued by having to wait a bit longer for your subscription copy of the mag. Evidently you are actually not happy with the content which is of course an entirely different thing. Why don't you email Kevin and say what you would like to see more of and, you never know, others might have suggested similar things to you. I am sure Kevin appreciates anybody taking the time to give him their feedback.
Anyway, I hope you continue to enjoy the hobby and are able to meet up with old friends soon. Also, I do apologise if I caused offence in some way, clearly not my intension. The last sentence was meant to be tongue-in-cheek by the way!
I think that might hurt you more than the magazine Malcolm, as you will end up paying more for your favourite magazine from your local newsagent, assuming that they have one in stock. In which case you might miss out completely rather than having to wait a few more days. Anyway, don't you know there is a war on? - furloughed staff, part time working, people working from home. Give the editor a break!
Edited By Piers Bowlan on 29/07/2020 13:28:49
|Thread: What glues do you use?|
Evo Stick claim it dries in 10-20 minutes and is stronger than other wood glues (PVA?). When dry is it sandable Chris or is it slightly rubbery when dry?
|Thread: Vintage Models KK Elmira|
Ops, double post!
Edited By Piers Bowlan on 13/07/2020 20:53:34
If Vintage Model Kits don't come up with a solution you could try some K & S tubing (ali or brass) to fit the wire you have if possible, or alternatively substitute a metric dia. steel or carbon fibre joiner and tube to fit. SLEC also do wing joiner tubes of all sizes.
|Thread: Ali Express|
I ordered some receivers from Ali Express a couple of months ago and it was exactly two weeks from order to delivery. Much quicker than expected considering the current global crisis.
|Thread: Help! Can't charge my Lipo|
I would say a Watt meter is pretty essential for anyone even dabbling in electric flight. How do you know what current your setup (prop/motor/ESC/battery) is drawing without one? This knowledge will pay for itself by avoiding burning out motors and ESC's. as well as finding a combination that will be reliable and efficient. They can be very cheap like this one or you can pay a lot more but essentially they do the same job. This one is much nicer! Alternatively, here but you might have to wait a while for it to arrive!
I switched to XT60 (and XT90 for higher Amps) connectors for all my LiPos after using Deans for years. Tip:- always plug male to female connectors together when soldering and use a big soldering iron as the heat will wick away very quickly along the wires otherwise. You need to be quick to avoid melting the plugs. I also prefer leaded solder, not led free.
Just my 2p worth.
Edited By Piers Bowlan on 12/07/2020 10:48:33
|Thread: The Ohmen|
Not necessarily Peter. By running it at a higher voltage, lower Amps can be drawn for the same power, depending on the prop used. This keeps the motor cooler and is usually more efficient, leading to longer flight times and a happier motor . Alternatively when in 'hooligan mode' one can take advantage of more power available for aeros. The choice is yours.
Either way Peter, it is a testiment to your design skills that Ballerina flies so well on a 3s setup.
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