Topic: The Whispering Death, Beaufighter Build

I am  looking at these  100 degree Lado retracts http://www.lado-tech.net/en/rs333/8-rs333-100.html

 hi
 i have a set of lado tech 90 degrees & all though they were a bit pricey they have been superb & are top quality  hope this helps your decsion a little
 andy

These are looking like a good choice, just deciding between 95 and 100 degrees. They are not that much more than the E-flight ones. I its handy that they have technical drawing so that I can print them out and put them over the plan.

In other news I just discovered that I had a PM in my inbox that I did not know about from 6 months ago  from John Ransom detailing how he made is undercarriage doors. He used cling film to stop the GF sticking to the nacelle and that seem like a good idea to me.

Well all my spare time has been wet and windy so far this week so no sanding has been done (If I did it indoors you would never here from me again)
 
Instead I have been revisiting the retracts.
 
I have been working out which of the Lado units  would be suitable


 
 
So I got hold of the drawings on thier website and stuck them down over the plan to work out where the wheel would be with 95 and 100 degree retracts. As you can hopefully see at 90 degrees they stick out a fair bit, but not quite as much as this pic would have suggested


 
 
At 95 degrees they are almost all the way into the nacelle, but very close to one of the spars. However the retract wil be mounted at a 5 degree angle and this will lift the centre line up about 2-3mm which should clear that spar. Or I could put and additional spacer under the retract.
 
With the 95 degree retract I could make a bulge for the wheel  with out it looking out of scale.
 
I don't know how TN fitted 3.5in wheels in there, mine are 3.25in.

I am now kicking my self for not having done this before building the wing, I could have cut that rib from 3mm light ply and cut the recess for the wheel into it. Now I am going to have  to do that through the nacelle 
 
There is about £40 difference in price between the Eflite and Lado retracts. Decisions decisions 

Well there was a lot of sanding this morning 




 
I am using the TLAR principle and to me this looks good. Any defects now I will fill with isopron once the glass is on. Just need to add the last bit of solid balsa at the back of the nacelle top and bottom and I can get on with making hatches and doors.
 
After that its shape the leading edge and glass the wing 

I have been looking for some commercial oleos similar to these ones


 
But they just don't exist so my plan is to get 4x oleo legs and buy some aluminium bar and drill three holes in it for the oleo legs pins and retract pin and then add some grub screws to hold them in place like in the one above.

I have found this site that sells the aluminium

http://www.aluminiumwarehouse.co.uk/Aluminium-Square_Bar/c120_136/p3081/Aluminium_Square_Bar_%286082T6%29_12_mm_x_12_mm/product_info.html

I think 12mm square should do the job. The oleos I would like to use are these ones http://www.lado-tech.net/en/accessories/43-rs333-legs.html as they work out considerably cheaper than others I have seen. As with the 95 degree retracts I need they are out of stock though which is ok as I am out of money at the moment

Nice sheathing Mhatter!

Thanks

It would appear that I have been looking at the old Lado site and that this is the correct one

http://e-retract.com/en/25-rs333

Which is a bit more expensive, now looking at £200 for the retracts and £60 for the oleos. Add on about £10 for the aluminium bar and I am looking at £270 for the retracts 

A set of Eflite retracts would set me back about £125. I think therefore that I might have to stick with the wheels poking out a bit and wire struts on the landing gear. It would be really good if Eflite would make some 95 degree ones

Your build is looking very nice there M, thanks for sharing 

One option is to do what I did on my Nijhius 72" Lanc (same looking retract arrangement).
I fould that at 70" spring oleo's are not really needed, so I got some units (I used Robart but I wish Lado had been around then!) and made the oleos from piano wire and aluminum square solid rod. I fixed the main rod in the top and oleos to the aluminum with grub scews and good threadlock. I dressed the legs with plastic tube or you could use Robart strut covers
 http://www.robart.com/store/strut-covers
They looked ok imho, and saved money and weight!

http://s1045.photobucket.com/albums/b451/Mudflap70/Lanc/?action=view&current=Picture048.jpg

Just a a thought,

Muds 

Thanks Mudders that is genius  I think I will do what you have done, and if I design them carefully I could still add some sprung oleos at a later date.

A couple of question on what you have done. Firstly how did you attach the axle at them bottem and secondly what guage of wire did you use ? I am thinking I could use 4mm and save a little wieght as there will be two legs supporting each wheel and possibly use some of these



To build in a little give in the set up 

Doing this would allow me to use the full size method of opening the UC door which is nice and simple 

Found these on the Robart site

http://www.robart.com/store/retracts/custom-add-parts



They would make it possible to get the wheel off with out resorting to cutting the axle. Shame ripmax don't import them 

I just put a 90deg bend in the bottom of each leg, if the wheel needs to come off I undid the grub screws and pulled the oleo's out. I really don't think you'll need the coil in the wire, on the lanc it was too short anyway to do that.

Those robart items look good, but unnecessary IMHO. nice though 

Muds

A little more progress over the weekend. I have added the fillets at the back of the naccelles, balsa on top and blue foam underneath to save a little wieght behind the C of G.







I started to make some blisters for the wheels , but trying to shape them to fit over the compound cure of the nacelle and be the right shape for the wheel is a complete I think have the wheels poke out a bit would be simpler, or maybe vac forming the blister then cutting it to fit over would be easier.
 
I have also finished installing the snakes, to to do this I had to trial fit the tail fins




The kink is there to try and make the final bit of the snake straight so that can have the metal rods go a little way into the snake for extra support. The transparent snake is for the rudder cables.

I have been having one of those days 

I decided to test the motor / esc today to see what props I should think about using and how much power I had.

First er, mistake.
Plugged in battery and was rewarded with a loud pop from  the some where. On checking the ec3 - ec5 adapter I had made up had it's polarity reversed. So good by to £50 esc
 
Having fixed this problem I then, using the other esc tested the props
 
14x7 7200rpm ~ 450W ~ 30A
14x8 7200rpm ~ 500W ~ 35A
 
These figures are way short of what I was expecting more like 600-700W and 40-50A. So those recommended props I was given are way off.  I think I would be flying round at full throttle ! 
 
I think I can prop up a bit maybe a 13*10 3 blade or 14*10 2 blade. Starting to worry that I have bought the wrong motors. 100W / lb on a war bird seems a bit low to me. 

I have had two whole days to build the Beaufigter so have been making some progress 

I have started on finishing the fuse. First up was to sheet the bottom half, which has some nice compound curves so I ended up planking some of it. Might have been better to plank all of it as the results where not as I had wanted.
 
Here is what it looked like after some rough shaping
 





 
What has happened is the sheeting as buckled in between the formers. I think I can fix this by running a knife along the join and re positioning it. You can also see that the transition between the side sheeting and thick bottom sheeting is a little uneven at this point. I can see some filler in my future.
 
This part of the fuse is cosmetic as it will be cut out and stuck on the bottom of the wing. You can see the cut line I left for reference. If I end  up with any thin areas I will put some of the heavier glass cloth I have on the inside.
 
I have since drawn on with a soft pencil all the shaping points. There is going to be a lot of sanding being done over the next few days
 

I have made up the UC doors, or the at least what they will be cut from.

Here are the moulds of the nacelles that I will cut the UC doors from.


 
To make these I covered the nacelle in cling film secure in place with double sided sticky tape. To my joy the cling film peels off the cured epoxy.
 
I have used this stuff


 
Thanks to Danny for the idea of using the Jenny brush in his glassing video
 
Here is the battery hatches being made
 
Cling film on
 


Glass and epoxy on


 
 
The are I have glassed again is much bigger than the hatch needs to be. The fibretech stuff is very easy to use and does not smell, a plus as I am doing this in the dining room.

Something else that I got from the local haberdashery is on of these



They cut the glass cloth with out fraying the edges.


Now back to that sanding.

I have done some motor testing today
 
With a master airscrew 14x9

 
 
And a graupner g-sonic 14x10


 
 
Results where taken after 30 seconds at WOT on a freshly charged 3300mAh 14.8V 45C Turnigy nano tech lipo. And then reduced to half throttle.
 
14x9x3 43.13A 614W 6300RPM Pitch speed 54mph Thrust 6.4lb
11.75A 174W 4050RPM Pitch speed 35mph
 
14x10 38.30A 530W 6330RPM Pitch speed 60mph Thrust 4.62lb
12.11A 185W 4440RPM Pitch speed 38mph
 
Looking at these results I think the 14x9x3 seems the better choice, in fact it should be quite lively. I am wondering if I will get better results when I use a 4500mAh lipo in terms of the voltage stability ?
 
In hind sight I should have chosen the motors to spin the MS 14x7x3 as they make a pusher version of this prop and I could have had them spinning different ways.
 
The keen eyed will have noticed the motors have lost thier nice red finish. When I masked them up to grind indents so that the M4 mounting bolts would fit the masking tape pulled the paint away

I have received some more goodies in the post and have been trying my hand at metal work.


 
 
My first attempt at the cross piece


 
 
Am now realising why the cheap drill bits I bought where cheap I have enough alloy bar for two more and a new set of drills on order lol. I have of course also been sanding, there is no end to the sanding with the beau fuselage....

Had the day off today so I have put the time to good use
I have a whole week off at the end of the month so I want to get the wing ready for glassing. So today I have profiled the leading edge.

To help with this I made a some templates
 

 
This is to help me make the "second" cuts on the leading edge. The top and bottom of the leading edge have already been sanded to the wing


 
With the template I can make sure that the second cut is the same along the length of the wing . You can see above that I have also used a marker to colour the front edge of the so its easier to see where I have sanded.
 


I then make the third cut,


 
And finally I use a strip of sand paper, wrap it around the leading edge and then pull it backwards and forwards to smooth off the profile.


 
Again on the outer wing panel






 
 
I have also been working on the fuse and have pretty much finished off shaping it to the correct profile
 
I have fixed the belly sheeting on the right side , here it is before sanding



It looks much better now.
 

My gut feel is that you'll need more pitch on those props. The pitch speed at full chat is barely enough, and it suggests the model will barely fly at part throttle. I'd be looking for a full-throttle pitch speed of 70-80mph so that your 60% power pitch speed is at least 40-50mph.

£0.03 supplied,

PDR

If that's the case then I might have to try different motors  something like this which has a slightly higher Kv ? http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idproduct=19618

I sanded some more the of the fuse today, and I think the bottom and sides are pretty much done.
 






Just need to go round with the red devil filler and fill in any small in perfections. I then add the remaining top section of balsa but before I do that I need to shape the tale fin so that I can dry fit it and fit the top piece around it.
 
Once I have done that I will cut out the belly pan section and test fit the wing, which also needs more sanding and the aileron hinge shrouds added.

this week I have started glassing
I started off by doing one part of the plane.

I used the belly pan


 
I am using fibretech, or as they are called now Bucks composites


 
I used a jenny brush and squeegee to apply the epoxy, on larger surfaces I will use a roller.


 
The results where quite good but I have some pin hole's on one section where the epoxy has soaked into the balsa

So I did the "optional" step of sealing the balsa for everything else. This consists of thinning the activated epoxy with 20% epoxy thinners, painting a very thin coat over the components and then wipe it off with some absorbent paper. Once its dried I then lightly sanded the parts before applying the glass.



 
 I will put the flow coat on later when I have more parts ready for it.
 
Today I have finished prepping the wing and put the sealing coat on.


 
I have already put the glassed the nacceles


 
It was easier than I thought it would be to get the glass fibre around the nacelle.
 
I am going to put the glass on in three sections on the underside of the wing tomorrow and to help me I have made these templates to cut the fibre glass sections.

[img]http://www.modelflying.co.uk/sites/3/images/member_albums/34079/2012_02020021.jpg[img]

Looking good there Mr Hatter. 
D. 
PS. ( Stay away from the Mercury for a while ! ) 

Thanks for the encouragement

The last picture should have been this one



I have glassed the bottom of the wing this morning
 
First I cut and placed the GF on the wing and weighed it down with clothes-pegs



I then used a roller to apply the resin


 
This work really well , and helps to spread it round very evenly with out snagging the cloth. The only thing is about 1\3 of the epoxy I mixed up ended up in the roller . It took about 80gr or 1/3 of the yoghurt pot in the top picture to do the whole underside of the wing (not counting what was in the roller)


 

Now just got to wait for it to cure and then do the top. This should be a lot easier as I can just lay the sheet of GF over the wing and but out what I need, no templates and cursing

Ok the bottom had cured by this morning so I trimmed of the excess, feathered down the edges and put the top sheet of GF on


 
I don't know what other peoples experience of the light weight cloth is but I find it next to impossible to entirely avoid disturbing the weave as I lay out and flatten the cloth over the wing, you can just see where it got moved here
 


Of course you cant see this once you stick it down
 

 
Again I am impressed with the roller, it seem to put on just the right amount to stick the glass down, spreads it around evenly and soaks up an excess.


 
I will leave it in this state until I have sorted out the retracts, and belly pan and put the finish on.
 
Now the question is what to do,
 
Fill the weave with primer ?
 
Or put a second "flow" coat of epoxy on ?
 
What are the advantages disadvantage of each ?

Apply the flowcoat. I've done it both ways, and was forever chasing pinholes by going straight to primer. You're also more likely to sand right through the glass in my experience. 

Flow coat it is then  How do you apply yours ? paint brush, squeegee, or combo of both ?

I decided to weigh the wing today in its current state and it is 2.5lbs 

I've done it both ways there. I find the paint brush a bit easier tbh, although you've got to be careful not to ladle too much on as you just have to sand it off again later! 

Squeegee is fine for wings etc, but it's not great for flowcoating concave surfaces. Or at least, I'm not good at it.

Thanks, I was wondering how I was going to do the nacelles with out the epoxy running  is the answer sand it off after 

Before that the next job is to cut away aperture for the UC doors on the nacelle and the same for the battery hatches. I think I will buy a new sharp razor saw first 

Been hacking into the nacelles and fitting the landing on one side
 




I carved away the rib and reinforced it with some ply, would have been much easier to do this before building it lol



And this is how far it will poke out, which won't be to much. You can see to pencil lines (just) on the side of the nacelle. The lower one is the scale size of the gear doors, the upper one would be the "easy" size for them. Not sure what to go for at the moment.
 
Here is a short video of the Lado retracts in action on a flat 6v battery.

Landing Gear Test

I haven't been keeping up with this build. 

Very impressed so far! Until I did glassing it terrified me that I'd get it really really wrong. I've not tried using a roller, using old credit cards and a brush; and surprised how little resin is used to get the right finish.
Re: flat battery, that looks about bang on speed wise! Are you having the servo slowed down when it's all set up?   

How about noise testing the servo?
Seriously - looking really good.
Mike

Yeah they are quite loud  not as loud as elfite electric retracts though.

No servos involved here these are electric retracts like the elfite ones (I think they pre-date those) you can buy a programming card to change their speed and timing, but I think the speed is just about right

Hi M,
I guess you may have seen this already ( There was a flyer about it in this months Flying Scale Models.)
A "Flypast" Special @ £5 for 100- pages of good stuff. Articles, archive photos, squadrons that operated the type, colour profiles etc, etc.
 In the Magazine shops today. Apologies if you have already made a purchase.
Nice story about the CO testing a Beau armed experimentally with two 40mm Cannon.
Ordered the armourers to remove the explosive shells and fill the cases with birdshot to make a flying version of a Punt Gun to go Duck hunting on Edku, quite successfully by the sound of things.
Hows the build going ?
Regards, D.

Hello M. ,
Nice work but the sound of your landing gear on Youtube has frightened the cat.
Looking forward to more of you work.  I like the glassing with roller.   What brand of resin?
take care,
Albert  , Phoenix ,AZ , USA

Thanks for that matrock19 I now have a copy of the magazine.

Well there has been a bit of a pause in building the last 6 weeks or so secret Due to good weather, planes being fixed after being flown in good weather and overtime. Also this new toy

http://youtu.be/Nyf9AQKmTqQ?hd=1

But balsa bashing has now resumed. I have decided to get the fuse to the point of ready to be glassed as it is showing signs of a little hanger rash.
So I have fitted the wing to the fuse, reinforced the floor of the battery bay and finished sheeting the nose section




I have laminated up several layers of balsa and cut the nose cone from them
Now there is just a lot sanding again. I placed a piece of ply in the nose side profile shape to stop me taking to much off.




Starting to look like something that will fly



The next thing to tackle is the tail plain seat



At the moment the fin will attach at the front and back with horizontal stab sitting on the fuse sides.



There is not a lot of support there so I have two ideas. One is to add some 1.5mm ply doublers that reach down to the thick part of the fuse sides for added support. The other is to remove the upper part of the fuse sides as far as the front of the wing and place a block of blue foam there. Then cut the slot for the fin and make a seat for the horizontal stab. Which do you guys think would be better/lighter ?

Finished shaping off the nose today. Suddenly added a lot of character to the plane 





I have also been looking at motors. A few pages ago I was testing the motors and I was not completely happy with rresults, in particular the pitch speed. So I have been looking at alternative motors and have found the following ones


http://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=18124


http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=19618


http://www.overlander.co.uk/tornado-thumper-v2-5045-720kv.html

So the choice is effectively between My original motors that are 620Kv and 650, 700 and 720Kv. I am kind of leaning towards the tornado thumpers at 720Kv and as usual there is no real prop data for any of these 

Hello M.,
Ref. post 145: I walked into the hobby store to have them take money out of my wallet that I really do not have and met a man that is building a nacelle type aircraft.  He has spent so much time on getting the doors perfect scale that I felt sorry for him.  I feel you should keep the landing gears close to scale and not shoot for perfection. Take the Easy path.  The gentleman looked exhausted and seemed very frustrated trying to achieve scale doors in a nacelles airplane, P-38 Lightning at 92'' span. Believe you me I know that it is hard to keep quality high and like Jaime says try to look ahead so you do not work yourself into a corner.  In all a great job, but keep at it.  Glassing with that roller is new to me , but have heard it mentioned a lot on this site.  I need to look into that.   In the compound curves I take a roll of toilet paper and bump into the concave tightly an roll out leaving a trail of toilet paper.  This sops a lot of the excess.  I still struggle with too much.  Some guys use up to 1/2 as much as I do, resin that is.  But we are talking grams of weight.  I met a man two weeks ago, from England with a prize winning Mick Reeves 1/6 Spitfire.  He advocated Mimwax with a water based lacquer system .  He said he uses it because it "floated" the weave of the glass up always in the center of the water based lacquer.  He says he uses multiple layers of this water based lacquer.  He said that each layer reactivates the earlier layer of water based lacquer and the glass moves to the center...or abouts.  Says, you never have to sand.  6 layers of the water based lacquer.  Prior to starting you have to seal the balsa with a varnish.   I had not turned a half turn away and thought to myself , " I will stay with a good resin method".
Enjoy and take care,
Albert

Well I have ordered one of the thumper motors to try out  hopefully it should be ok.

The next two jobs are not ones I like but I need to get on with them.

The first is to accurately cut the tail plane seat so that the tail plane incidence is correct. Now there is no info on the plan to say what it should be frown In the build the article TN mentions that on the original one he built, the tail plane incidence was out and he adjusted it on the new plans.

Now I am guessing here that the incidence should be 0 degrees    ?

After that I have the wing fillets to make. Question is build the fillets then glass the fuse or the other way round ?

I have made some more progress



The top of the fuse is now the right shape and I have made the over landing gear



As you can see in the first pic I have started on the fillets, and then cheated a little and simplified them. I started off making them exactly scale and then realised this was a bit ambitious for my first set of wing fillets, and scratch built at that 

So i settled on these






As you can see I straightened the forward sections out a to simplify things. The full size ones are very curvy. The next thing to do is to put the curves into the ribs and skin them. I am not entirely sure how to go about this so I have left it to another day 



The radio was switched on a the start of building so it took me 3-1/2 hours to get this far crook

Now to some electrical strangeness. I tested the Thumper 5045- 720Kv motor with the same ESC, Lipos and props as I did with the Emax 4020 620Kv (roughly equivalent to a 5055 580Kv).

And got nearly identical RPM and current results, So 2 motors with a 100Kv difference give identical results ?? Anyone got any ideas what is going on ?

Hello M.,
I like your techniques on the wing fillets and this thread is a great one.
Take care,
Albert

I have got some more work done 

The fillets have been skinned, a little more filling and sanding to be done on them



I have cut the hole of the rear canopy and shaped said canopy to the fuse




I have also made a start on the removable cockpit which will have the switches underneath it



I need to finish glassing the rear tail and fin before setting the tail plane incidence and glueing them together. So I decided to start putting the flow coat on the wing 



I made sure I put on enough epoxy to fill the weave and no more. It looked good to begin with but I had a look a minute ago and could see some of the dreaded pin holes appearing. This was despite sealing the bare balsa before laying the glass on. Oh well that's what filling primer and putty is for 

Hello M.,
Looks excellent from here.  She's a big bird.
Take care,
Albert

Thanks 

It looks a bit better now, however I am wondering if I put enough resin on for the flow coat. When I put it on the surface was flat and shiny, now it's cure you can just see the pattern of the weave underneath. Having never done this before I don't know if this is good or bad.




One cockup though, I must have pushed the brush to hard on the leading edge, when I flipped the wing over I had this