West Wings Merlin, completed at last!

Back in October I started constructing a West Wings Merlin glider, however, I got distracted and never got around to finally completing this kit.  I refrained from any fancy paint job as I wanted to keep as light and clean looking as possible, sometimes less is more.

Over the Christmas holidays I managed to find a spare couple of hours to make a new tail (since the last one warped during the final doping) and to finally glue in the wing and tail-plane dowels.

I am rather pleased with the final result.  I just need to balance and trim the glider and give it a go once Spring arrives and the winter storms are behind us.

Fixing power issues on my Dell 1525

The family laptop is a rather old and well used Dell 1525 laptop that runs Ubuntu.  Over the past few weeks it has had difficulties charging the battery and last week it finally gave up the will to live.

I found a handy service manual online and stripped the laptop down and found that the DC power jack daughter board had failed.  After some more research I found that this component has a history of failing this way, so I felt more certain to risk spending some cash and getting replacement. I managed to find a new replacement part for less than £5 (including postage and packaging) on eBay which promptly arrived a couple of days after ordering.

Is was both annoying that the board had failed perhaps because of poor design, yet also a relief that a cheap daughter board replacement could fix the issue without the need to replace the entire motherboard.   Within half an hour I had replaced the daughter board and re-assembled the laptop and fortunately it worked first time.  I later discovered that there is a video on YouTube explaining how to do this fix, which I wish I had found earlier!

Anyhow, the machine lives on, hopefully I can squeeze a few more years of use before it finally succumbs to old age.

West Wings Merlin

Earlier in the year I purchased a rather old edition of the West Wings Merlin that had been languishing in the back of the local model shop for quite a few years.

I was hoping my son would build this, but it was a little too tricky for him so I decided to build it.   Like previous West Wings kit, the balsa is a good grade and well selected.  The plans are very easy to follow and in just a few hours of work I had the 35" wings and fuselage constructed and ready to cover.  Not bad at all, an excellent beginners model.  I just need some spare time to cover it and I will report back on how well it flies.

Visit to the Eden Project

While on holiday in Cornwall this Summer I visited the Eden Project with my family.  The Eden Project is built in a 160 year old china clay quarry near St Austell in Cornwall.

The Biomes are an incredible examples of engineering - the Rain-forest Biome is the largest conservatory in the world and large enough to fit the Tower of London inside!

There are also hands-on exhibits too.  There are den building materials such as bamboo poles, rope and coverings that the kids can use to build large dens either outside or inside the white den making building.

 The Eden Project provides an excellent mix of engineering, art, ecology, ethics and education.  It is incredible how creative minds have turned a disused clay pit into an amazing ecological environment.

Keil Kraft Senator Covered

I eventually got a few spare moments to cover the Senator with some really garish orange tissue. Since covering, the tail has warped a little, so I need some extra work to tease it back straight again. I just need to make a couple of balsa wheels and attach them to the wire undercarriage.

Senator Construction Completed

I've now found time to cut the nose block from laminated 1/4" balsa sheet and finish off the propeller assembly.  I used some brass tubing that could accommodate the 18 SWG wire used for the propeller shaft and epoxied this into the nose block.  Some brass washers between the 12.5" propeller and the nose hopefully will reduce the friction.

I acquired various coloured tissue from my local model shop and I think I will cover this in garish orange rather than something more subtle.

Senator Tailplane Completed!

I've now completed the tailplane to the Senator. It took longer to construct than I anticipated because I was rather fussy on cutting the curved tips and ribs exactly to shape. I think I'm happy with the final result, however, we will see how it works out once it is covered as I suspect it may warp if I am not careful with the shrinking of the tissue.  The 1/16" wing spars were fiddly to cut and I hope they are strong enough.

The wide-angle lens on the camera is distorting the image.

Starting to take shape

 Next.. making the wing tips!

Keil Kraft Senator Tail Fin Completed

Spent some of this afternoon constructing the Senator tail fin. Not a demanding build as all the parts are just cut from 1/8" sheet balsa.  Most of the laborious work came in the sanding and ensuring I didn't break the weaker parts.

And now onto the tailplane..

Keil Kraft Senator Fuselage

Although it was a very busy week I managed to find some hobby time by working on the fuselage of the Senator at sunrise and also very late at night.  My intent was to follow the plans exactly and to keep the weight as low as possible. However,  I decided to add some more rigidity by adding some extra diagonal bracing on the underside of the nose.

To try and avoid any warping I also added two 1/8" sheet formers in the box section under the wings and behind the nose section.  The nose was a little more challenging than I anticipated and I had to re-cut the sheet balsa three times before I was finally happy with shape and fit of the nose panels.

Not too bad really, no warping and an improvement on the fuselage I built when I was a teenager.  Just a little heavier than the original design, but I hope to save some weight on the wing ribs.

Keil Kraft Senator

While looking for another suitable rubber powered balsa plane to construct this Summer I stumbled over the 32" wingspan Keil Kraft Senator.   I recall building this a teenager and I got some remarkably good flights out of it.  I can't recall why I don't have this model anymore, I suspect it got lost or broken during the last house move.

The model is still in production and is available from the Vintage Model Company but I was really looking to rebuild it from scratch from the original plans which is a little more challenging.

After some searching around I found some plans online and also an excellent article on constructing the model by Craig Limber, with some useful notes on building the propeller from scratch.  I need to rummage around to see if I have the original plans, otherwise I will see if I get a legitimate copy somehow soon.

This 1950s Keil Kraft model is a classic and I look forward to constructing it.

Completed Sapphire

I managed to find some spare moments to cover the Sapphire with yellow tissue and apply some cellulose dope. Once this was completely dry, I drilled some 3mm holes and fitted the dowels for the wings and rubber motor.  My minor gripe was that the dowel provided was less than generous, but fortunately I had some spare from a previous kit.

The final steps were to fix the wheels, add in the windshield and get the propeller nose block finished.  The nose block balsa was a little softer than I expected so I ended up sanding it just slightly too much, so I may redo this at a later date.

All in all, not a bad little kit. Straight forward to assemble, the majority of the parts were very good quality and the instructions and plans were excellent.  It didn't take too long to build and it was an enjoyable experience.  I just now need some fine weather to fly it!

Build complete!

Today saw the completion of the building phase of the West Wings Sapphire.  I added some more 2.5mm square diagonal supports to the fuselage to give it more rigidity and hopefully I can crank up the rubbing winding a little higher than original designed.

I eventually got around to cutting and sanding the wing tips out of solid balsa block which wasn't so difficult as I first anticipated.   The nose block (not shown) took a some careful shaping but I've not yet drilled it and inserted the propeller shaft.

I'm rather pleased with the final outcome.  I just need to find some time this week to cover the Sapphire with tissue and prepare it for flying!

Fuselage now shaping up..

This weekend I managed to find a few spare hours to assembly about 80% of the Sapphire's fuselage.  I wasn't too difficult to build.  The kit required splicing two pieces of 2.5mm square strip balsa to make each of the bottom fuselage longerons - instead I hand cut full length ones from some 2.5mm thick sheet balsa which I hope will be slightly stronger.

The fuselage formers F2 and F3 that give the initial rigidity to the body were a little too flimsy for my liking.  The 1.5 mm thick front former split on the grain, so in retrospect I think I should have cut my own formers from 2.5mm balsa for added strength.  As it was, I added some balsa strip along the top and bottom of the formers to add some extra strength.

I just now need to finish adding the width-wise balsa strip to complete the main body and then I need to knuckle down to shaping he nose block.

Craft Saw Set

On my last visit to The Hobby Box I splashed out on a Expo 735-44 razor saw set. 

This comes with a handle and number 234 and 239 razor saw blades.   I've been using these to accurately cut balsa fuselage longerons and stingers to size.  I'm still unsure if they provide a better result than using a very sharp craft knife, but I guess it is good to have a range of sharp cutting tools handy to help with any balsa kit build.

Sapphire Wing Construction, Part 3

The bulk of the wing construction work is now complete on my West Wings Sapphire.  All I need to do now is to hand carve the wing tips out of some block balsa and then the surfaces are ready for covering with tissue.  Next step, the fuselage!

Sapphire Wing Construction, Part 2

I've now completed the initial construction of the wing tips and main wing section to my West Wings Sapphire.   I need to now shape some 12 mm square balsa for the ends of the wing tips and glue the wing sections together at the correct dihedral.

Shaping up quite well.  I hope to move into the tail and tail plane later this week if I get free time.

Sapphire Wing Construction

Last week I was given a West Wings Sapphire 32.5" wingspan rubber powered model aeroplane kit for Father's Day, however, due to a really busy week I only managed to some free time on Sunday to start it.

With most models I normally construct the wings first. This model has two large wing tips and a main wing.  It was a relatively easy build. First, I pinned the plans down to a board, wax the paper to prevent glue sticking to it.

The ribs were pre-cut, so it was a case of popping them out of the cut sheet and tidying them up. The leading edge required cutting the 3 mm x 6 mm down to 3 mm x 5 mm and sanding down the front two corners to make a leading edge profile.  The trailing edge required notches to be cut about 1.8mm deep to accommodate the end of the wing ribs.  There is some under-camber to the ribs that required the front underside of the trailing edge to be wedged up by 1.5mm before pinning it down and gluing in the ribs and then the spars.

I took an enjoyably slow paced two hours to finish the build.  I'll try to find time this week to build the wing tips and finish the wing.

Webcam Bird Watching

My son has been begging me to rig up a camera to record the birds on the back garden bird feeder.

I lashed up arrangement of a small HP netbook running Ubuntu 12.04,  an old webcam and my camera tripod on some old bricks.  My first attempt was to use the "webcam" tool from the xawtv package, but the camera kept on falling offline and closing prematurely when the light levels dropped too low.   So, I just ran the "cheese" webcam tool and set it to video record mode and this worked reliably.

We left the rig to record about 40 minutes worth of video and then copied the video over to a more powerful laptop to edit the video using mplayer to allow me to skip to the interesting frames and ffmpeg select and re-code the webcam feed into mpeg video.  The quality of the webcam is not great as it was an old second hand one I picked up for free several years ago.  We've ordered a cheap webcam with higher resolution, hopefully we will get better results next weekend.

Here are the edited bird feeding high-lights:

Restart Parties

The BBC has an excellent report about Restart Parties occurring in London.  A venue is chosen and advertised and encourages people to bring along either their fixing skills or gadgets that need fixing.

The outcome is that gadgets get fixed rather than being condemned to being recycled or ending up as landfill, and hopefully some education on fixing skills is imparted too.

West Wings Sapphire

This year my kids gave me a West Wings Sapphire for Father's day.  This is a 32.5" (825mm) wingspan rubber powered sports aeroplane that apparently has high lift and good stability as well as promising some long duration flights.

Inside the box:

The quality of the wood looks good, the plans are clear and the instructions are well thought out and easy to follow.  It looks like it will be an enjoyable build.  The West Wings website does mention that one can finish this model with heat-shrink covering, but I will stick to the traditional tissue and dope finish.

Not a bad kit at all.  I've never built a West Wings kit before, so I look forward to seeing how well it builds and performs in the air.  My only quibble is that it came with a rather chunky yellow propeller rather than the more aesthetically pleasing blue one as shown on the box.

Making an indoor balsa wood chuck glider

I've been meaning to teach my 10 year old son how to build balsa wood indoor chuck gliders for some time, so today we visited The Hobby Box, an excellent model shop in Uckfield, East Sussex, to purchase some balsa.

Materials list:

• 1/16 x 3 x 36 inch balsa sheet for the wings (1.6 x 75 x 915 mm)
• 3/32 x 3/32 x 36 inch square balsa strip for the fuselage (5 x 5 x 915 mm)
• PVA wood glue
• Metal ruler
• Modelling knife
• Fine sand paper

I created a design in metric because that's easier for the modern metric thinking child to deal with.

Components:

• Fuselage: 25 cm of the 5 x 5 mm balsa strip.
• Tail plane: 2 cm x  9 cm from the 1.6 mm balsa sheet.
• Tail: 4 cm high x 2.5 cm base x 2 cm top trapezoid from the 1.6 mm balsa sheet.
• Two main wings (left, right): 3 cm x 18 cm rectangles of the 1.6 mm balsa sheet.

Construction:

Cut the fuselage from the 5 x 5 mm balsa strip.  Cut out the tail plane and tail.  Glue the tail plane to the end of the fuselage. Gently sand to smooth the edges. We used tiny pins to hold it in place while drying.

When dry, glue the tail on top of the tail plane.  We used some Lego bricks to hold it vertical while drying:

Cut out two of the 3 cm x 18 cm main wings from the balsa sheet and glue these half way along the fuselage.  I decided to have about 3cm of dihedral so 3 Lego bricks to hold the wings into position while drying seem to do the trick:

We also glued a small slice of 1.6mm sheeting on top of the wings to add a little more strength on the join.

Finally, add a small blob of Blu-Tack or plasticine to the nose to balance the chuck glider.  Ensure the chuck glider balances when one holds the plane with a finger under each wing tip.  Add more weight if it stalls, remove weight if it nose dives.

My son built the chuck glider in the pictures under my instruction.  It was the first time he had used a metal ruler and a modelling knife for cutting, so some help was required to get him to cut straight and confidently.   After he was happy with the tailplane he measured and cut the tail and wings all by himself.  I explained the way to trim the glider and in no time he had it flying perfectly.

By our reckoning these cost about 50 pence per glider to build.  Not bad at all.

Fixing the volume control on a radio.

The volume dial on my relatively inexpensive digital radio has recently been crackling and working eratically.   The fix for this relatively easy by just applying some electrical contact cleaner.

First, one has to open up the radio.  There were two screws on the top back of the case, one inside the battery compartment and two sneaking away under the rubber feet on the bottom of the case:

Screws indicated by the helpful arrows on the case

Screw hiding under a rubber foot pad

Opening the case required a little bit of wiggling to pop the headphone socket out of position.  One has to be careful not to snap the socket off the mounting, but apart from that it isn't too hard to do.

Next, a small plastic cover over the volume control had to be removed to reveal the potentiometer.  A small spray of electrical contact cleaner followed by exercising the potentiometer back and forth to work the cleaner over the dirty metal contact surface is enough to do the job.

Cleaning the contacts of the potentiometer does the trick

After re-assembly the radio works as good as new.

Foam Plane Repairs

My son and I went out this afternoon to fly some of our model planes in the nearby playing field.  After quite a few successful flights the tail on my son's foam jet snapped off.

This is a simple repair using a thin spread of glue and some tape to hold it together while it dries.  This has worked well with previous breakages and we hope to be flying again next weekend.