Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length.

[Langsford]

I have read some excellent instructions from Bluebird on this subject but am still confused!!!! Bluebird spoke of building from wood but one contributor said that he would only use "plastic". Is it usual to build hulls from this material? Also, I cannot get my head around "diagonals". Can someone explain please. I have the plans for the Liverpool Pilot "Edmund Gardner" and I am aware that there is a Fibreglass hull available, but I would really like to build from scratch. Bluebirds information is superb but "diagonals" have really foxed me. Cheers, John

[Martin13]

John,

Good idea - have a go at scratch building your hull from ply. I tried Bluebirds method of Double Diagonal Planking and had a lot of fun in the process - try it and you will have a hull that will make you proud not to mention the strength in the hull. Check out this post I started late last year.

Go to Nautical College - Tutorials and How To's - Subject, Fibreglassing a Hull.

There you will find many sketches and photo's explaining the process. Also look at the Masterbuild section of Bluebirds Whaleback build. If you still have problems - send Bluebird a PM - I know John will only be too pleased to help you out.

Hope this is of some help (Bluebird's Quote)

Martin Down Under

[John W E]

Hi there John and Martin - G'Day

John, before we indulge and begin about building hulls and so forth - may we just clear something up in my mind please?

What is your interpretation of 'diagonals'.   There are two types of diagonals that I know of in regard to hulls and plans.

On the plan; there are sometimes diagonal lines drawn through the end elevation or the 'frame plan'.  Approximately mid-centre of the plan out towards the outer edges of the drawn frames at approximately 45 degrees.   This line is an aid for the draftsman to check that the frames he has drawn are true and fair with one another.     Where this diagonal line intersects the frame line, this reference point is plotted on the profile plan.  It produces what they call a 'fair curve' that is if the draftsman has got his lines right.

These diagonal lines on the drawings are not really detrimental to us; we do not need them and certainly they are nothing to worry about.   I can assure you that many a model has been built without the use of these lines and they are only there to satisfy the draftsman.  (Just to ensure he has not made an error).

The other diagonal is the type that Martin13 has mentioned.   These are in regard to the diagonal planking.

However, before we go down this road of explanation we will await your kind response.

The other thing you mention are using plastic materials to build hulls with; now, every modeller normally has a preference of his working material.   My preference, as I have stated before, is working with wood.   I can work with other materials such as fibre glass and a tiny bit of plastic work too.  Slowly improving my skills with working with plastics.

There are numerous modellers who have built many a fine hull - purely from plastic/plasticard if you prefer.   Like every other material we use in modelling it does have its good and bad points.   It is entirely up to the individual how the material is viewed - is one happy working with 'X' material.    Just as a side note, and, also as an added comment.   When I first started modelling - when Noah built the Ark you know    one of the favoured materials was indeed tin plate.  The type which was used in the 'old' baby milk cans.   What they would do is make a solid mould up from wood for the shape of the model hull, and, then they would bend the appropriate sized tin plate around the plug and solder them into place with one of those big old-fashioned copper soldering irons (the type you would heat in a fire/gas stove).

We very rarely have seen this type of hull manufactured - food for thought for the future -    so, there are a couple of ideas for you Sir.

Hope this is of some help.

Aye
john e
bluebird

[Langsford]

Thanks to both Bluebird and Martin from "Down under".
I'm not quite ready for the "old tins" approach and I, like you, prefer to work with wood. I found Martin's thread very informative and the whole concept of this forum is invaluable to those of us new to this hobby.
The diagonals I asked about are those shown on the end elevation and I'm pleased that I don't have to worry about them. However, I still can't quite work out how the draughtsman uses them as an aid to design :-\.
Thanks to both for the helpful responses,
John

[John W E]

Good morning there

John, I have copied a drawing from a book which I have - its called 'Ship Modelling from Scratch - tips and techniques for building without kits' its by Edwin B. Leaf - 
and the ISBN Number it is 0-07-036817-1 .

This book is mainly aimed at the 'static modeller' and is primarily concerned with hull construction and fittings, plus, drawing your own plans and reading plans.   I have found this book very, very valuable at times.  You can purchase it from Amazon - but, however, you may find it at your local library to check it out first to see if you find it suitable.

Inside the book 'When you have completed your new drawing, check the lines for accuracy with diagonals.  Since the diagonals reveal the accuracy of the sections; plot them directly onto your drawing rather than enlarging them from the original.   Smooth, evenly curved diagonals mean the frames can be planked evenly.  Deviations indicate sections that are too big or too small in places.'

Hope this little snippet helps you to begin to understand the meaning of using diagonals 

aye
john e
bluebird

[Langsford]

Thanks Bluebird, will study and inwardly digest! A phrase from my chemistry teacher some 60 years ago. John

[dougal99]

Bluebird

Thank you for reminding me about that book. It's sitting on my shelf and will be very useful revision for a project I'm working on. I've attached a picture of my model of the Brockley Combe which features in the book. It's a heavily modified commercial hull with scratch built deck and superstructure.

Cheers

Doug

[Langsford]

I have now finished double planking my hull and the next thing is to apply fibreglass and resin. Before I start are there any tips or warnings?
Cheers, John

[John W E]

hi there John

is there any chance of seeing a photograph or a picture of your hull, before you attack it with fibreglass and tissue?   The reason I ask this, is, sometimes with double-planking there is no real need to apply an application of fibreglass resin and matting/tissue.

We can sometimes get away with one or two coatings of polyester resin with hardener added to seal the hull or, if you prefer, epoxy resin.   Normally, I would apply epoxy resin, if we are going to apply a resin on the hull without any matting, epoxy is a lot tougher than polyester resin.

aye
john e
bluebird

[OMK]

Thanks Bluebird, will study and inwardly digest! A phrase from my chemistry teacher some 60 years ago. John

Sorry to take it slightly off topic, but amidst all this fascinating reading I couldn't help noticing what Langsford had said. For my chemistry teacher (a Mr. White) had the habit of saying the exact same thing (although, in my case, the era was the late '70s - not like Langsford's 60yrs ago).
Ironic that two chemistry teachers from differing epochs should both use the same words (but I'm glad they did, just the same).


Excellent sketches, John (Bluebird John, that is). You don't know it, but you've taught me more than any teacher at school could teach about such things.

[Eddy Matthews]

Using "diagonals" to check a hulls lines can be very useful - How often have we built a model from a plan only to find one or more of the bulkheads/formers are obviously incorrect? It's annoying to say the least, and if the bulkhead is badly out of shape it can make the hull virtually impossible to build!!

The following link helps to explain all the hull lines, and has a very good explanation of how the diagonals are used: http://books.google.co.uk/books?id=m-a8viwFFRsC&pg=PA16&lpg=PA16&dq=%22plotting+hull+diagonals%22&source=web&ots=Dm186D20Mt&sig=13sjBpmPdrUCVLHiglUqLsZFMAI&hl=en&sa=X&oi=book_result&resnum=4&ct=result#PPA10,M1

The link should take you straight to the correct part of the article, but if it doesn't, read page 10, and the section entitled "The Lines".

Regards
Eddy

[Langsford]

The hull seems fairly substantial as I have double planked it with 0.8mm ply for each skin. This is the first time I have tried a hull from scratch and as Bluebird mentioned the fibreglass I assumed that would be the best thing to do. The pic shows the start of the second layer and the hull as it is now. John

[John W E]

John hi there from another John

Looking at the pictures of your hull - LOOKING GOOD MATE - if this is your attempt at a scratch built hull - you are doing really, really well - it would appear as though the bow section is made of balsa wood.

Taking this into account, I would suggest that you coat the hull first of all with a coating of Polyester resin with hardener mixed.   When the resin is still 'tacky' on the hull, apply another coating of resin on and then apply your tissue matt.   Stapple the resin through the tissue matting; when this layer has gone 'tacky' apply a further 2 coats of resin over the top and allow it to cure for at least 48 hours.   You then can rub back, with wet 'n dry to produce the desired finish on the hull.

Just a note, it is a pity you apply the bilge keels, as what you will need to do is cut the matting so that it butts up to them; where they meet the hull - do not try to go over the top of the bilge keels with the matting as this will result in the matting trying to lift off and cause air bubbles underneath in the corners.

Hope this is of some help.

aye
john e
bluebird.

[Langsford]

Thanks Bluebird, you always give a positive response and encourage us beginners to keep going. I have made quite a few mistakes and have had to take a couple of steps backward during this hull building process, but I think it is coming together now. I wish I had my present knowledge when I started but thats what experience is all about. I will continue to follow your advice and let you know how I get on.
Cheers, John

[John W E]

hi there John

from the other John

I did a posting for Tiger Tiger the other day with regard to fibre glass tissue and resin; at this present time, sod's law has just kicked in and I cant find the thread.   Have to go back through me postings.

However, the crux of the thing is; there maybe some advice there to help you with your fibreglassing.

 

aye
john e
bluebird

[DickyD]

Hi John, the other John appears to have gone off for another (yet another) tea break. :angel:

Here is the link he was on about.

http://www.modelboatmayhem.co.uk/forum/index.php?topic=12361.msg117195#msg117195

[Langsford]

My Liverpool Pilot Boat hull is coming along slowly but I have now finished the fiberglassing. I found the second planking difficult as I was using .8mm ply and the ply did not take the pins well when I did the second skin. In fact I abandoned the pin idea and used cyno which worked well but more expensive and also I became quite attached to the hull a couple of times. Bluebird was right when he suggested obeche as the planking material. Will try that next time. Thanks to Bluebird for all of the instructions he has posted on this forum.
John

[John W E]

hi ya John

Your build looks really smart - me ramblings have been some use thank goodness    please do keep us updated with your build - are you going to plate the hull? using either Plasticard or thin craft card?  Now there's something for ya to think on - I can well imagine your answer 

How did you find fibreglassing and rubbing it down?

aye 
john e
bluebird  :)

[Langsford]

Hi Bluebird, I had not even thought of plating the hull. I have previously plated a deck with card and intend to do that at the bow end of this model. All of the stern end is timber planking. If I do decide to plate the hull, and I don't think I will at this stage, do I then just give it paint and varnish to keep it waterproof?
The effort it has taken to get this far has been considerable, not least all the rubbing down.
I am hoping to make most of the fittings from scratch and have made a start on the forward anchor winch but I am guessing a bit as it is not obvious on the plans and the actual vessel has it covered up with canvas.
One thing that I am not sure about is there are a couple of details on the builders plans that are different on the actual ship. Should I stick to the plans or build her as she is?
Will keep you informed as I progress.
Regards, John

[John W E]

http://www.stationroadsteam.co.uk/archive/2421/index.htm

Hi john this may help you 

aye

john

[John W E]

hi there John

I put this link on last night - I was quite knacked    I would not take this particular model, which is shown in the link above - as to be really accurate.   I am sure it is based on the Vic Smeed plans judging by the shape of the stern.

It should though, give you some guidance towards the anchor winch & some fittings.

As far as your dilemma is concerned with regard to building from the plans or the full sized ship...what we have to remember is, if they are original builders' plans, these will be as she began her life - new from the slipway.   No doubt even during building of the vessel, things would have been altered on the ship.   So, even then you would find differences between the plan and the actual ship.

If you build from a plan, you could say - this is how she was when she was first launched.   If you build from the full size ship it will give you a little more scope, for variation of fittings and so forth.

aye
john e
bluebird