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[Martin13]

John e,

I called the company yesterday re attending one of their classes but unfortunately the course is only ran the first week of each month and currently booked out till mid next year. 

Oh well, looks like back to the trial and error method.

Currently 5.45 am Aussie time - must prepare for work -

Cheers  Martin from Down Under

[Martin13]

G'Day to all,

Unable to get a response from the thin plywood supplier - oh well, doesn't matter.

I wish to say thanks to all for your input on this thread and to all that sent pm's - I've had a few, and am very grateful for all the ways to complete the task at hand.

Seeing that I cannot currently get hold of thin ply, I have decided to go with the balsa method of construction prior to glassing and try not to be heavy handed (found 50 sheets plus on a shelf).
When I have gained more experience , I would really like to try the diagonal planking method - it looks great but the only thing is, If I was able to make it look like Bluebirds model - it would be a crying shame to paint over it............

Thanks again to all for your patience and input - it is much appreciated...

Martin from Down Under

just for interest - local time 1945 Hours

[John W E]

G'day my mate and how's the roos and wallaby's todoy then? 

hI YA Martin from doon under!   

There is really nothing stopping you having a go at double diagonal planking with balsa wood.  Obviously, the first layer of planking you would not need to put any resin on that, but, just be very careful when sanding and use blocks of wood of various shapes and sizes to wrap your sandpaper around when sanding.

I use several of these blocks of wood of varying shapes and sizes from half round shapes to wedge shapes & so on.    You will find that you end up with a collection of block pieces of wood that you can never find when you want them to use as sanding blocks, but, do not forget one major thing when you start to build PLEASE PUT A BUILD THREAD ON HERE WITH PHOTOGRAPHS and then we are kept informed of how you are getting along with your build.

BEST OF LUCK.

John

[John W E]

Hi again Martin

Whilst doing some research for another project, I came across Model Boat Magazine December 1976 and this runs an article on Making a Model using balsa wood as frames, and double diagonally planking it with cereal packets cut into strips.

A quick read through, it would seem as though the cereal packets are cut into something like 10mm wide strips, to be used as the planks and the model is planked diagonally - when the first layer of planking is complete - it looks as though it may have been coated with either a polyurethane paint or a sand n sealer and then the outer layer is applied.   Obviously planking in the opposite direction and then over the top of this, they are talking about applying a coat of mat/fibre glass cloth and if you are interested, let me know I will see if I can email the articles to you.

IT MAY BE WORTH LOOKING AT 

I do know Colin (Bishop) has built serveral models in a similar way, but, what materials he uses I am unsure.   Maybe Colin can come in and explain.

Food for thought my Friend.

aye
John e
bluebird

[riggers24]

For the old hands from the Model Boat forum, this is mmgemini's cardboard Thames barge. A good example of what you can do with cornflakes packets.

[John W E]

Hi there,

Yes, Marc, I forgot all about Mike - I am not sure if he still comes on the forum now??? Mike has a wealth of experience and information of building models out of different materials.  I think he may be in Africa now, driving his Land Rover? somewhere 

aye
john e
bluebird

[Martin13]

G'Day to all

It absolutely amazes me what you people come up with. Not in a million years would I have thought about using Cornflake packets

Would it be suitable considering the size of my model ?

John, I have printed out a copy re your photo of diagonal planking and have it on my wall in my workshop - I use it for inspiration.
And yes, interested in anything you can supply on the subject.

Build Thread - After spending many many years in Avionics within the commercial and military fields, coupled with large amounts of stress, resulting in severe brain strain - my head hurts :( :( :( and have now entered the area of brain shut down with respect to anything to do with computers and electron flow.

Basically what I am trying to say is, I am hopeless with personal computers and digital cameras (I prefer my Nikon SLR) coupled with the fact that I am rather slow with modelling due to swmbo input . But if the forum doesn't mind the thread running a little slow - I will con the swmbo into photo taking and posting onto forum - after all, she's the IT expert.

Thanks and Thanks to all

Martin from Doon Under

[Colin Bishop]

I've not actually used cornflake packets but that sort of cardboard if impregnated with dope/sanding sealer or shellac is a perfectly good material for coating hulls. My preferred method for liner type and similar hulls is to build the basic structure of composite balsa. By composite I mean "economical". As the bottom of the hull is usually flat then you start with a suitably shaped piece of sheet balsa upon which everything else is built. The next bits to go on are the stem and stern frames in plywood. I usually cut a groove in the stem to accept a length of brass bar so that when you hit something you don't take a bite out of the stem profile. The midships body is usually parallel sided so I put a balsa bulkhead at each end and use sheet to make up the sides with a substantial square fillet along the bottom to allow for the turn of the bilge to be carved without going through the material. The extremities, bow and stern are usually block balsa while the bits in between where there are curved profiles are dealt with by a bit of plank on frame using extra bulkheads mounted on the bottom section to give the right shape.

The whole thing is then carved and sanded to shape but not sealed. I then use gummed paper strip to coat the hull, laying it along the hull to simulate the inner and outer strakes of plating. Instead of wetting the gummed paper with water I use Cascmite/Extramite water based resin glue which bonds the gumstrip to the underlying balsa. As gumstrip contracts very slightly as it dries you get a very tight fit to the hull. The next step is to paint sanding sealer or shellac onto the gumstrip which impregnates it and makes the whole thing waterproof and solid. It rubs down to a superb finish very easily. Then complete the job with your favourite paint finish Humbrol, Halfords or whatever.

[Martin13]

Hi there Martin

If you go the plywood way and use plywood as planking, 1mm thick plywood cut into 8mm strips would do the job.   Personally, I would go for 0.5 or 0.6 mm plywood, or whichever is the best option for you.

I would cut the plywood into 8mm thick strips.

Now, I have included a little scribble, which may assist you in how to diagonally and double-diagonally plank your hull.    Once you have all the basic framework set in, where you have your keel/chine/stringer/deck edge stringer in place - it pays you to add bottom stringers.   The more you add in, the closer you will get to your bottom hull profile.   The same on the sides, because the hull you are proposing to build has a fair amound of flair at the bow end.

When you eventually come to start to plank, my personal preference is to commence approximately at the centre of the hull - mid-section.  Your first plank should be approximately 45 degrees angle to the keel.

As you plank towards the bow, you will note that the angle of the plank will increase.  This is normal.  My normal method of planking, is, to do 5 planks one side of the hull/5 planks the opposite side of the hull and by that time the 5 planks on the other side are dry (i.e. the glue has dried).

Then, I go 3 planks one side of the 5 and 3 planks the other side of the 5 (in other words 3 planks towards the bow and 3 planks towards the stern).   Once they are, I do exactly the same on the opposite side.

When the hull bottom is complete with one layer of planks, I do the sides in exactly the same method - i.e. 45 degrees from the deck edge at mid-section of the hull.

Once I have the full hull completed with one layer of planking, I lightly rub it down to remove any abnormalities, fill in any hollows with P38 filler and then apply my 2nd top layer of planks in the opposite direction to the bottom layer of planks.

Once this has been done and I have sanded and filled - I then proceed and give it a coat of polyester resin with hardener mixed. 

I hope this is of some use to you.

aye
John e
bluebird

John/Bluebird

I have decided and started to use your method of double diagonal planking for two reasons:-
1. I'm busting to try this method - something new
2. Due to size of model and that it is a planing hull, it needs to be quite strong and I don't believe balsa will give me the strength in the hull

As per you method, I have started to diagonal plank the hull beginning from the centre.
Currently I have about 20 strips laid on the bottom 10mm x 0.6mm plywood and am surprised by the strength in just one layer. I can see this is going to take some time to complete but I'm in no hurry and am enjoying another way in skinning a hull.

Is it necessary when laying the strips to glue the edges (not easy to get glue on the edge of 0.6mm material successfully). Currently I am getting glue oozing out and building up on the surface of the planks which will need to be sanded off prior to fixing second layer.

Your advice would be much appreciated,

Martin doon under