Monday, 3 August 2020

Beautiful 1/4 Scale K6e Glider for sale

My 1/4 scale K6e glider is up for sale for the bargain price of just £350.
Its a stunning looking 4m sailplane which comes with all servo's and a new battery pack. It is covered in cream solartex on the wings. The model has been beautifully built to a very high standard. It has a full scale cockpit and pilot.
Open for viewing - contact me for further details: paul.hampshire@shelf-space.co.uk


















Sunday, 2 August 2020

It has been a while since I have been able to get out flying. I met up with Scotty and Robert Powell at Mill Hill yesterday morning. ATC were duly notified and asked us to keep an eye on our height as the previous weekend had seen some models flying higher than they would like.
Scotty flew his little red Messerschmidt which went very well (as always). Robert flew his needle and erwin which both looked very graceful and smooth in the air.
I flew my Strega which was going lovely until the right aileron linkage came loose and the model did some very funny things at not a lot of height. Partial control was regained, just enough to get her back to the landing site (aka a bush). Luckily no damage, just need to rescure the linkage.
I then tried my repaired again phase 6 but somehow the model had disappeared from my transmitter. quick bind and setup and she was ready to go. She flew well having been put back together with glass and poly C both inside and out on the fuselage. Had some lovely flying and looking forward to getting back up on a hill soon.
John

Tuesday, 21 July 2020

Flying anyone?

Hey guys, it's Steve here from A470 Soaring in S Wales.

I thought I'd check out your page here and can't see that anyone has been out flying? So have you? If so, where are the stories, pictures & videos?

Here in Wales we were restricted to only travelling a maximum of 5 miles until 2 weeks ago, but now that has been released the guys have been finally getting out. So check out my video below of my 1st excursion to the slopes and I look forward to seeing what you've been up to again soon.


Friday, 22 May 2020

Flamingo HW-4

Why the Flamingo?
Last year there were a couple of articles in RCM&E which caught my eye, the first was an article about the Ecirtech Hexen slope soarer and on looking at the French website I found that I was drawn to the company’s Bannsperber vintage glider. The Bannsperber would make a great builder’s project but before I took the plunge there was another article in the RCM&E about the 1/5th scale Flamingo HW-4 slope soarer. I liked the idea of both models as they were going to provide a significant build project and after much ado about nothing I plumbed for the Flamingo as I thought it more suitable for the slope.

The Flamingo was a Brazilian glider of 1947 vintage glider with a gull wing and high aspect ratio, the model I’m building will have a wingspan of 3.5m.


Flamingo build
From the RCM&E article I had the free plan but it would have needed a significant amount of copying to make it useable to build from. Over the lockdown I ordered a laser cut short kit from Laser Cut Sailplanes (LCS) and a pack of additional spruce, balsa and plywood from Sarik hobbies. I went to LCS as the guy there was more forthcoming with information regarding the plan than I could glean from Sarik even though I phoned them up.

The wood that arrived from both companies is of good quality and a full size plan is thrown in free of charge by LCS. I’m sure the purist would ask why I am not cutting everything out myself but I have done that in the past and there is enough of a build so I make no apologies for having bought laser cut ribs, frames and other parts that need to be accurately cut out. One half of the fuselage is built over the plan, the whole then being completed by building the second side directly on to the first half.

The first part was to laydown the keel (no it's not a boat) and the first two parts supplied by LCS didn't match properly as shown below which would mean that the plywood to be fitted later would not connect to the frame properly.


This wasn't a problem as I have plenty of time so I contacted LCS with a photo and they quite happily agreed to replace the ply leading section. However, it was a very useful discussion because as you can see from the photo the joint is just in front of the wheel bay. In the build once the fuselage is built the keel has to be removed in the wheel bay to allow the wheel to be fitted so why wasn't the joint in the wheel bay removing an additional join? The guy at LCS offered to provide me a replacement as a single piece in either 6mm hard balsa (as per the rear piece) or a single piece of 6mm ply hence no joint - I went for a single piece of plywood.

So the build commenced:



Having the single piece for the front keel I was able to cut out the 6mm balsa for the top and lower rear sections and then to lay it down and then add all the frames followed by the spruce longeron. I used a set quare to ensure the frames are correctly aligned. One aspect of this build is the lengths of wood required. Standard balsa and spruce comes in 915mm (36") lengths, which for this model and 1/5th scale is too short so you either join bits or pay more for longer lengths - I've joined the spruce longerons under the wing and extended the upper keel section. The best tool I've bought at the SRFC auctions is the balsa stripper - just the job for those long lengths of balsa.


The build is comencing well though it's slow as I prefer to use pva type glues rather than cyno. The first side had the initial 1.4mm plywood added to the nose section before removing the side from the board ready to add the second half. The plywood has been added in sections a bit like building a clinker boat as the plywood needs to be moulded in 3 dimensions, water and some heat to encourage the bending of the plywood helped greatly.


While the glue holding the plywood was setting I was able to start cutting to length 6mm square balsa and putting it in place between the frames on the top and bottom keel sections and adding diagonal bracing between the longerons and the keel top.


Once the plywood was glued in place I removed the fuselage half and set it up horizontally using a spirit level so I could again use the set square to align the frames.




31st May

I've been plodding along this last week as my motorcycle decided to play up big time (a sump full of fuel doesn't make life easy) and it's now in bits in the garage - more to do in the near future.

Back to the Flamingo, the build is progressing slowly as most of the tasks seem to be those where you do a little and wait a long time for glue to dry or wood to bend in water.

Since completing the fuselage frame I have completed the nose plywood planking and sanded down the balsa bracing and inter-frame pieces in readiness for the top 0.8mm plywood skin which has been cut to shape, bent and glued to the frame from frame F5 to F12 as per the photo. A lot of clamps are required even if the balsa has been pre-shaped.


It looks good though once the plywood is in place.

  

With the plywood in place the next job I did was to remove the three temporary frames (F2-F4) in readiness for a bit of fibre glassing.


I'm doing it in two stages as I need to glass behind the cockpit between F5 and F6, which hasn't been done so far, that's tomorrow's job.

 In the mean time the plywood skin has been cut out to compete the top skinning from F12 to the tail. As I write the piece of plywood has been cut out and it is soaking in order to get it in the right shape as it becomes more difficult to bend it round a sharp curve the further back along the fuselage one goes.

7 June 2020

More progress to report. The top of the fuselage has now been competely covered in 0.8mm plywood. Working with plywood when some of the angles are very tight, particularly at the top and bottom of the fuselage is a challenge but leaving the plywood wrapped in damp clothes overnight does the trick.


And then the fuselage gets a nose.


Next came the tailplane, which is built upside down. Unfortunately the plan gives you one dimension but not the other, which is also true of the elevators and rudder so beware.


To get the right angle of dangle three tailplane holders are provided in the laser cut kit to hold the centre and end ribs in the correct position and then all you need is a weight to hold the tailplane down while the glue dries.


One tailplane securing bolt and captive nut ready for installation in the fuselage.


The elevator TE is made from no less than nine separate items per half elevator so I used cyno in this case as I needed them to dry flat and cyno seemed to be the best way of doing it. The TE is made of a plywood core surrounded above and below with balsa.


A 1.5mm wedge is used to position the TE in the right place where it attaches to the LE.



All the ribs need some adjustment even though they are laser cut as the laser cutting is square whereas from the picture above you can see the ribs attach at angles to the TE and LE.


Rudder assembly is very similar to the elevators with the TE needing a fair bit of work to assemble and then to get the ribs and diagonls attached to the rudder post in preparation for fitting to the TE.


22nd June

Slow progress recently thanks to many other things taking priority. The tailplane has been completed so too the fin, rudder and elevators. The fin is finished in plywood though each side is separately skinned so it's not too difficult. However, the elevator control linkage will be totally enclosed in the fuselage so before I want to or can finish putting the lower fuselage plywood skinning on it is a must that the elevator controls are installed.

The first job was to make the elevator horn, which is made from sheet brass with a 2mm od steel rod soldered together and bent slightly.


The horn is then screwed and glued to the elevator that's strengthened with ply.


As access is going to get more difficult as the fuselage is covered in plywood I decided that it was best to install the elevator and rudder servos and to connect them to their respective surfaces as it would be impossible to secure the bowden cable and outers within the fuselage at any point other than the extremes.


The elevator is connected to the bowden cable with a ball joint that is allowed to slide up and down the horn rod and as can be seen below access soon becomes very difficult.


It might sound OTT but it took me about five hours to satisfy myself that the elevator linkage and servos were as I wanted them to be before I finalised everything and moved on.


After the elevator controls were connected the fin could be fitted to the rear of the fuselage for which I mounted a rule in the cockpit in order to check that the fin was vertical, I used the frame centre joint as my master reference.


The fin trailing edge is a substantial thickness (approx 18mm) and blocks access to the elevator control linkage, connecting the elevator control every time the model is put together at the flying field is going to be an interesting exercise.


29th June

Some more progress this week although if you look quickly you will wonder what I've been doing. The first item I worked on was the shroud that fits above the tailplane to form the lower part of the fin and is removable to allow the tailplane to be fitted and removed.


After the shroud I started bending and fitting 0.8mm thick plywood behind the cockpit to close out the lower half of the fuselage.The plan shows it being closed out with just two pieces on each side but on closer inspection the fuselage behind the cockpit can be split into three disinct sections:
  • The first two frames have a curve in three dimensions with the keel in a gentle curve which stops and straightens aft of the second frame and to my mind created a natural break
  • Behind the first two frames there is then a section that covers three frames ending in a change of lower keel angle, which takes you to the original designers break point
  • The third section is the area to the rudder.

Another advantage of doing it in three sectiions is that the two rearmost sections can be done as a single piece wrapped over the keel and allows the front and rear sections to be fitted which still leaves access to the inside to secure the controls bowden cables inside the fuselage, which I did with some of my wife's cotton tied around the bowden cable and with a little application of cyno makes a secure fitting.

I've never worked so extensively with plywood and I'll be honest, it's been a challenge. I started by using steam and heat but I've found it best to prepare the plywood for bending by soaking it with water. A good overnight soaking with a wet rag wrapped around the plywood and using either rubber bands or tape to encourage it into the correct shape has proven to be my best approach.





I have found working with plywood very hard work but gives a very strong finish when done.

The next was to prepare the rudder controls, which means inserting a 6mm diameter dowl into the rudder LE to receive the 3mm control horn.


And then I connected the rudder control to the servo.


Now the fuselage has been skinned with plywood and the rudder shroud is in place I'm rapidly reaching the point to remove part of the lower keel in the wheel well so I can fit a wheel and the tail skid before applying car filler to create a smooth covering of the plywood planking around the cockpit and of course to fill the nose section with Isopon.

6th July

The wheelwell has now been created and the application of Isopon has begun. To be honest it's more a case of putting Isopon on and then spending four times longer taking it off to get a smooth finish. The first comment I must make though is that the nose takes a huge amount of Isopon and the 250ml tin of Isopon that I thought would do most of the nose only just filled the nose and that's after first adding four chunks of lead too. It's a messy job and it's best to have some overalls on with a face mask and to do it outside as it really smells if you try doing it indoors.


It's years since I used anything like Isopon, the great thing about it is that it hardens sufficiently to sand in around 20 minutes but the downside is that it has a very short working time so you have to work quickly. In fact the recommendation in the instructions is to mix a small amount and make more as necessary, something I've come to realise is very good advice.


When I took this photo I had already done alot of clearing up and this was after the third application of Isopon. I've shaped the nose with 80 grade sandpaper and I'm in the process of getting a smooth finish with 120 grade with the 320 grade awaiting its turn.


27th July

Time seems to have stood still recently and progress has been painfully slow. The shaping of the fuselage is mostly complete and in recent weeks I've been looking at starting the wing build, which is when a few issues appeared.

All the laser cut parts I bought fitted the templates on the plan but when I laid them over the plan I realised that some of the ribs and the aileron diagonals didn't fit the plan view of the wing. In addition I couldn't find any information on the plan to create the gullwing break nor the angles required - fairly basic information. Emailing the supplier of the kit and the designer illicited a pdf file with the wing support building supports and a comment "the information is on the plan". On my plan the information was missing though I did find it on the plan in the RCM&E December article. The saga continued as I then realised that my plan differs to the plan in the RCM&E in that the root chord and span are larger on mine. After much emailing and phone calls I received some recut aileron ribs and diagonals and a new plan from the designer. The plan is different again!!!! However, I now have enough to build a wing and parts coming out of my ears.

First thing you're supposed to do is pin the TE to the board and attach ribs to it and the lower main spar but if you don't lift the TE up 15mm the ribs won't sit on the spar properly.


Having fitted all the ribs (R1 - R9 on the TE and lower spar and R10 to R28 just on the spar) the assembly has to be lifted off the board and mounted on the wing supports. At this point I realised that another very important bit of information was not explicitly stated - the point at which the gull wing bend is. Initially I thought it was at R9 but on looking VERY closely at the designer's photos I saw that the peak of the supports was between R8 and R9 and about a cm from R9. R9 needs to be vertical to the spar so that the aileron which is immediately outboard fits against an upright component.







So far I've fitted the inter-rib webbing to R11, only got to fill in to R28. All webbing is in 0.8mm plywood.


While I've been waiting for the glue to dry I've started building the cockpit canopy, which is made by laminating 3mm x 6mm strips of spruce and bending to form the canopy side frames.



4th August

Progress is being made with the port wing slowly, I had to wait for the wing joiner metal work to arrive in stock and now I have it the wing joiner is in place and all the inter rib webbing has been cut and glued in place (all 28 of them). After the webbing and wing joiner had been fitted I was then able to cut the ribs to install the sub-spar top and bottom, the sub-spar going in front of the webbing to form an H section.


Sub-spar in place and gluing - I used aliphatic as it takes time to get the spar in place and it needs to be sanded, the top one I used clamps and my wife's clothes pegs but for the lower sub-spar I used tape - you choose which you think is best.



At the gull-break additional spars are fitted either side of the break within the D section and then the hidden LE is sanded prior to fitment of the top and bottom sheeting.

Another little job to do is to fit plywood stiffeners in the inner section of the wing.


The next job is to use a straight edge to ensure the wing TE in front of the aileron is straight prior to fitting the bottom sheeting on the bottom of the wing's D section.