Topic: SE5 restoration

Can anyone offer any advice?

Norfolk is right, it's a process called scumbling. 

When the London & North Eastern Railway stopped building wooden coaches out of teak, they simulated the effect of varnished teak with this process although it was a little more in depth than Norfolk's simplified version.    Out of interest the process is described about half-way down this page.

Me? - I'd buy a wooden prop, then over varnish with mahogany varnish.    There's nothing quite so like wood as wood

HTH

Alan B

Laser don't recommend wooden props, I've no idea why. I'd like to fit one myself!

I'll have to have a go at this simulated effect - probably on an old prop first.

Don't forget to post the results Giles 

After an extended delay here are is an update on the progress of my model.

I have recently added the radiators to the front of the model. These have had to be a compromise between form and function. I was concerned that if I added too much at the front of the engine I would restrict the flow of air over the engine and have overheating problems. Therefore there are not enough slats in the radiator when compared with the full size aircraft.  In the fullness of time I may rework these to be more accurate. I have to be happy that the model looks good when taken as it is, when compared to reference pictures of an original it is clear where the compromises are.







The Laser 200V is using scale exhaust pipes that run down each side of the fuselage.  A flexible Mick Reeves exhaust pipe runs from each cylinder through the dummy engine heads that stick out of the cowel and into the dummy litho place exhaust headders. This pipe is concealed behind one of the four exhaust stacks that run between the heads and the exhaust itself. You can just see it behind one of the two central pipes in the picture below.



Concealed within this exhaust is a the home made muffler for the exhaust - by that I mean the actual exhaust rather than the dummy scale one. This is a copper pipe (heating pipe) which acts as a baffle and turns the air through 90 degrees and then out into the pipes that run down the side of the fuselage. I'll take a picture of this when I next have the dummy engine parts removed.



I have flown the aircraft in this configuration. In fact I flew it for a while with just the functional exhaust to prove that it worked, then I constructed the dummy engine and exhaust.

I'm really pleased with this result. It was about 18 months ago that I made the decision to ditch the nasty Super Tigre 3000 two stroke and buy the Laser 200V. It was my hope at that stage to construct a scale exhaust system concealed within a dummy engine. Some have said that I should have just let the exhausts exit below the airframe, but I have persevered with this and it was well worth it.  I spent months of trial and error making the exhausts and learning how to silver solder. This design gets 100rpm more than the standard Laser exhausts.

Here are some pics of little bits of detail I have been adding to the model:

I have been following this build from the beginning - keep at it!

Here are some images of work in progress on my Aldis gunsight. Brass tubes and some threaded bar. I'm quite pleased with it. It needs to be quite strong as it plays an important part in keeping the Lewis gun on the top wing. I'm thinking there will be quite a bit of drag around this gun, and I don't want it to come off!

Before I restored the model it would nose over quite a bit on landing. When I rebuilt the fuselage I moved the u/c forwards about 15mm, so the axle is further forwards than before. I also improved the bearings of the wheels so they roll a little better. Since the rebuild the model has never nosed over on landing. So I have some confidence in adding top wing details!

Speaking of Lewis guns. I'm having a scale dilemma!

In the picture below, the print out is a 1/4 scale Lewis gun. My model is a 1/4 scale DB SE5. The full size wingspan is 8.12 meters. 1/4 of this 2.03 meters. My wingspan is only slightly longer than this. The larger balsa model in the picture is roughly 1/4 scale - the smaller plastic kit is something even smaller.



The problem is that when I refer to other images of the SE5:



The gun looks much smaller than the 1/4 scale print out of the Lewis.



The reference I have for a Lewis gun is that it is 40.5 inches long - or just over 10 cms. This looks far too big on my top wing. I'll take pics of this shortly.

Any thoughts on this?

Hello,

Sorry I can`t remember where I got this from, but these are the specs I have:

Lewis Gun Specs:

If you are thinking of building one the specs may help for scale:

Specifications
Weight    28 pounds (13 kg) (not really relevant )
Length    50.5 inches (1,280 mm)
Barrel length    26.5 inches (670 mm)
Width    4.5 inches (110 mm)

I'm pretty sure that the quoted length of 50.5" is for the infantry version with shoulder stock (and therefore a good bit longer) not the a/c version. I've actually handled (but not fired) an infantry Lewis and from memory 50" long sounds about right.
HTH
Mike

I think that is correct about the infantry version. The GA that I have is certainly for the handle grip type Lewis and shows the overall length at 40.5 inches. The version with a stock could easily be another 10 inches worth.



The problem I have is that when looking at pictures of full size aircraft the 1/4 scale Lewis plans I have just make the gun look too big!

I'll get a pic of this mocked up on the top wing once I finish my Aldis mount.

Sorry about the previous reply, didn`t realise it could have been the infantry version.

Just measured the gun on the Dennis Bryant Elite plan, it is 9 5/8ths"  244mm  and has the pistol style grip but not the `D` shaped handle  as shown in the drawing posted by  gilesfordcrush.

I haven't had a chance to make any progress on the SE5 recently, but I have been able to get a little done on my 3d one. Here is a quick render of the wing. Very much work in progress though.

looking very nice

I know it is missing its ailerons!

Any more on the apparent anomaly over the Lewis?
Mike

Giles, this is the drawing i have of the Mk11 Lewis

Steve

As far as the Lewis gun goes, I have finished my Aldis gunsite and mounted it onto the fuselage. I can now mock up the two models I have of Lewis guns and see what looks right.

One problem I can see is that the Aldis gunsite has the metal runner for the Lewis gun fixed to it. I think it is called a Foster mount. I need this part to be strong enough to hold the gun on. However, by nature of the fact the strength of the top wing is given by rigging wires, it is possible that the top wing will move around a little. This could mean it loosens the Aldis mount from the top of the fuselage.

Something to bear in mind when working out what should be bolted to what!

Any movement here Giles?

I've had another extended period of inactivity with my model, due to extra cold weather and being out of the country with work for a few weeks too. Such a drag having to travel to South Africa and spend every day in the sun on a film shoot!

I'll be getting on with the finishing touches on the SE5 soon.

I'm pleased to report that I had a good flight with my SE5 on Sunday. Although I am still going to be adding the details that are missing it was nice to get it flying. It is such fun to fly too, very settled in the air. Getting a good turn or landing is a real treat compared to how smaller models fly.

I did have the Laser cut out on me a couple of times. It was a sudden and total engine shut down, whilst the running was perfect for the rest of the time. I think this must be the failsafe circuit I have for if the radio signal is lost, which closes the throttle. If the engine lost one cylinder then it would not have just stopped. The engine would restart immediately, there was no overheating, the fuel had not been changed. I'll try it without the failsafe and see if the problem goes aways.

Isn't it better to set the fail safe to set the engine to tickover rather than to stop it completely?   That way a brief interruption of signal quality is recoverable and probably safer.  The model will still come to earth quite quickly in the event of a total loss of radio contact.

Geoff

Isn't it better to set the fail safe to set the engine to tickover rather than to stop it completely?   

Geoff

That makes sense 

That does make quite a bit of sense.

The problem here is a "knowledge gap" in so far as I didn't know I could set the failsafe to idle rather than fully closed. I'll see if I can change this.

Thanks for the suggestion

I don't know if it can be done with your radio gear but with my JR system I set the failsafe to set throttle to tick over and a gentle turn to left.  With my SE5a I also add a touch of up elevator because the "glide" angle is quite steep without it.

It would appear that my limited knowledge of radio systems has lead to me using the most antiquated receiver! I cannot set a failsafe as it is not PCM whatever it is called.  The failsafe I do have is an inline thingy between the receiver and the throttle servo. I did set this so an idle position rather than closed as Greyhead suggested, and on my last flights all was well.

I should learn about these things and get a more up to date receiver! i wonder if they are cheaper now 2.4gig is all the rage?

The bungee material I'm using on my undercarriage keeps snapping. It is elastic I got from a dressmakers shop. I wind it around the axles and u/c quite a few times and it seems very strong, but not strong enough.

Can anyone suggest an alternative? I've tried rubber bands too. I'd like to keep something that gives a little on landing.

sailing/dinghy shops/ chandlers sell thin bungee cord.

I buy mine off the roll at B&Q, they have various diameters to choose from.

Mud

I got mine from Ebay, something like THIS

Thanks for the reply, I've ordered some and we'll see how it does.

I have not made much progress on finishing off the detailing of my SE5 recently. But I have been flying it quite a bit. I'm still having problems with the undercarriage bungees.

At the weekend we stuck an iPhone on the side of the fueslage and got the following result. It is very wobbly!

<a href="http://www.youtube.com/watch?v=QagjU0oddRA" target="_blank">http://www.youtube.com/watch?v=QagjU0oddRA</a>

What's going on here then Giles?  Did you do any more detail work?

I've been flying the model quite a lot, but I'm still keen to finish the details. It is just a question of finding the time"

As long as you are enjoying it that's what matters 

I flew mine all be it briefly at Barkston over the weekend.

I had a serious problem with this model the other day - I lost my aileron control. Thankfully they had frozen at neutral so I was able to land using rudder only - but it wasn't a great landing and caused some minor damage. The fault was traced to a loose connection in one of the servo wires running to one of the aileron servos. There are two servos, each in the lower wing running from a Y-splitter.

I'm wondering if I should cut these connections off and solder them so this cannot happen again. Is this a good idea? Should I use the genuine Futaba wire for this?

Giles

Assuming you mean that the plug/socket joint came loose, rather than an individual pin failure, I'd suggest that you use a piece of heat-shrink tubing to encapsulate the plug/socket.

Works for me.


Mike

Assuming you mean that the plug/socket joint came loose, rather than an individual pin failure, I'd suggest that you use a piece of heat-shrink tubing to encapsulate the plug/socket.

Works for me.


Mike

Do that or you could use an Ashlok type connector if they're still available.  I heard Ash Jones was closing his  business but I'm not sure.  He also sells suitable servo cable.

I'm surprised you're using a Y lead rather than a channel for each servo.  Are you short of receiver channels?

Geoff

I've got plenty of spare channels, but I've always used Y-leads for the aileron servos. Is there a good reason why I shouldn't be?

I'll give the heat shrink a go.

If you use separate channels then you can use aileron differential (if your TX has it) without having to build it in using the control horn / servo arm geometry.  This is where the ailerons move up more than down, which eliminates adverse yaw, a common fault on early aircraft designs such as the SE5a.

Co-ordinated turns using aileron and rudder is the “correct” way to do it but it’s a lot easier to let the TX do the work and you get consistent turns every time!  Coupling in a little rudder with the ailerons also helps.