SE5 KK-OZ1320

I've got the KK-OZ1320 drawn up enough to be able to start building it.

By measuring off the OZ PDF drawing I got all the dimensions so have drew out the wings & fuselage views & all the ribs & formers.
I printed out the wings & the fuselage on A4 sheets to build on but when I checked the dimensions they were about 2.3% undersize, the fuselage measured 10.75 " instead of 11".
I spent over two days altering the settings on the LibreCad & my printer preferences but it kept either wanting to print it a quarter of an inch undersize or a quarter oversize. I eventually got them to print correctly by exporting it from LibreCad as a PDF file & printing it from that.

I laid out the fuselage sides, formers & ribs on to suit the 12" x 3" sheets as in the KK kit but of course that doesn't suit an 11" A4 sheet so I had to squeeze them up abit. Plus it was difficult to print the fuselage sides without losing a bit off the end but managed to get there in the end.
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I printed the ribs onto normal A4 paper, masking taped it to a sheet & cut round them which works quite well as long as you do it methodically.
For the fuselage sides & formers though I decided to print onto an A4 self-adhesive label. The printer handled it well apart from a little smearing because of the high gloss on the paper. The idea was that it would make cutting out the small formers with small cut-outs for the stringers easier.
The formers are ellipses which makes it difficult to draw the cut-outs at 30 deg and 60 deg so I've just left the radial lines & will make the cut-outs by eye.
I wasn't sure how easy it would be to peel the label off the balsa so I cut out the section of the stencil with the tail-plane & did that separately to reduce the contact time. This proved to be a good ploy because the label had to be coaxed off & it stripped out some of the surface like you see when a wasp has been collecting wood off a fence.
I will have to experiment with some sort of barrier layer to reduce the stickiness.

With the fuselage sides & the formers I intend to leave the paper on as it will add some strength without too much weight. It will be on the inside of the model so won't be visible.

So I'm half way through using the stencils & have started to make the wings.
I'm using the strip-wood from the kits as I don't have any, it'll be easy to replace next time I do an order which hopefully will be for the Alpha which I've almost finished laying out so the next stage on that will be doing the detailing for the laser cutting, hopefully that won't be an arm & a leg job.




 

experiment with some sort of barrier layer to reduce the stickiness.
What we used to do was LIGHTLY stick it to some plate glass, then immediately remove it again. Do that several times (practice will say when is enough) as it wears out the 'sticky' so it doesn't grab so hard.

Make your own strip with a plank of balsa, a steel straight-edge, a hard backing board (that glass again?) and a sharp knife, rather time-consuming but a darn sight cheaper!
It used to be possible to buy a commercial balsa stripper that did exactly that, but I've not seen them advertised for a long time. I'm prettu sure that SLEC used to make one.

If you have a laser printer, borrow the bosses Iron, place the print ink down on the wood and Iron away, job done.

Yes Slec make a good one or did, i have one used it all the time when i was building, bet Slec may still do one
Lat time i look at slec to order balsa as i used to always use them they only had hard balsa in stock   so i went to balsa cabin

There are balsa strippers on ebay for about £15. Looking at them I would only attempt to cut short lengths, say up to 12 inches, without a cutting board & clamps. I think I would find it as easy just using a steel rule & scalpel.

I've got the wings done ready to cover & fix on & been on with the fuselage.
With this type of construction with sheet sides its difficult to hold it square while adding formers etc so I've knocked up a jig from an old kitchen unit shelf & some left-over cork.
 
It's still a bit fiddly especially with the 1/16th being so thin. My dexterity & eyesight isn't as good as it was sixty years ago.
With the far side propped against the back of the jig its difficult to glue anything.
The water-based cyano also tends to make the balsa swell so if a former comes away from its cut-out it tends to swell so not fit second time around.
I don't remember that problem with the old balsa cement so I'm going to get some for next time. The cyano is great for wings which are more stable anyway.

I've made a couple of changes from the original KK design.
The fuselage had airfoil shaped cut-outs which sat on the the centre section of the lower wing. I've done away with the cut-outs & made it so the fuselage will sit inside between the two inner ribs & can be glued to them on assembly.
The fin was just sat on top of the centre stringer, I've added a tapered  former between the sides with a slot for the tail to fit into. There was no provision for fixing the tail skid so I've used another slotted tapered former to carry the skid.
The nose former just being 1/16th doesn't have much for the sides to glue to. I should have doubled up on it.
I've made the nose-block removeable using what I think is now standard practice of a square location piece which will also make replacing the rubber easier.

 

Cyano is not water based, I suspect you mean Aliphatic glue. I find white wood glue works just as well. Yes the old Laquer based balsa glues worked very well. Nice to see you're having fun, if you can find any, cork gasket glued to an old piece of MDF works very well.

Yes I mean Aliphatic.

When I went to buy my building board at the local hardware store I found that MDF was about the same as ply.
He keeps his prices competitive with the major DIY chains, you can check there are no shakes or bad knots & if you only need say 600mm he will cut that off. Deep within his vaults he has things you've never heard of!

I have used up all my oddcuts of everything.

PVA wood glue, from a builder's merchant. A litre bottle costs a couple of quid, and lasts for ages. Dries clear, and very slightly soft, so it peels rather than cracks. Being water based, it washes off your sticky hands, too!
Aliphatic tends to be more brittle, and dries a bit yellowish.

But sands easier than wood glue!

I didn't think PVA would stick to the remnants of the self-adhesive coating which even today is still tacky.

Ah, Eric and I were talking about using PVA glue for modelling, not for sticking cork tiles.

Wrong end of a different stick! 

All you need on the MDF is a piece of plasterboard no need to glue it a couple of screws will hold it in place if you are moving it around, if not then just lay it on
pins easy and you can cut on it, and when it gets worn you can bin it and replace, cheep as chips, i use nothing else for years