I am plan to make a fiberglass boat hull, Starting from the basics i have many questions about it in my mind....

1,I am having a 3D plan for a cat then how to start?

2,Is that i have to make a same boat peace from clay to make a plug out of POP?

3,How to start with 2 piece plug making?

4,Going to fiberglass, which epoxy and what OZ cloth to use for it?

5,Is Gel coat important?

[would like to have detail discussion about it,Pl don't give any direct reference to some other links]

I would love to have those questions answered as I have been sitting with all required materials (Cloth, Resin, Chopped mat, Cobalt etc.) for the last 2 months not knowing where / how to start!

Vc sir,
The first thing, i am having a 3D plan but no idea about how to mold it out,
I went out to 'murti valas' they told they would charge me 4K  for making a plug of around 4 feet in POP if i am having a same peace of Boat in wood or else they first will make the boat as in plan out of clay then a 2 piece plug out of it!

hi guys.
you need to make a pattern of how the hull will look when finished.
that would be complete and fine finish and polished......... then you use this to make a mold for the fiber glass, this will be a hollow mold that you would use to make the final hull by 'layin up' the fiber glass 'inside' the 2nd mold.
that is why the first mold needs to be 'perfect' as the hull will be exactly the same finish as the first mold,
you will need 'release' gel type application on the mould to enable you to get the hull out without damage.
if you google mold making there are a few tutorials out there.
it is long laborious job ,,,especially if you only want 1 hull of this size and shape
I usualy build a hull as normal and then cover with card or such and fiber glass that ....then if you need and 'empty' hull you can always remove some formers from inside after as you can break then away from the 'card' skin.
regards
don

Hi Ghanshyam I am planning for a Fibreglass Hull myself. I am going to try the mold with Foam( Thermacole). All though it would be a one time mold... but would be very easy to prepare.
It would be pretty easy to remove the foam from the fibreglass. a little heat to the foam once the FG is cured , the foam melts and you can have the hull good to use. In fact you can leave a little foam in the front of the hull as Floatation.. So no need to add additional floatation.

Shreekant

When you have a 3D plan go for CNC cut, this will give you a perfect hydrodynamic shape and also required for a speed boat. As you are in Bangalore, you could get someone who is having such CNC machines.  

hi mate,
hows the hull coming along?
regards
don

Hey every one,
So excited to be back after a long long time.
I am starting with a new Catamaran boat with the same plan of Mystic 5000 with a bit modification and this time in Fiberglass.

Started working by getting the plan printed in A1 size will post the exact measurement as i am done with the cutting stuff.
1>I am planning to cut down the hull frame work on plywood of 3mm then will cover it with other thin                    wood and build the exact model of the boat.
2>I will then make a plaster of paris mold out of the model.
3>At last i have to experiment with fiberglass and build the entire boat out of it, after some research i have got some basic of how to work on fiberglas and have some sources to get raw materials for it.

will be posting pictures on every stage as i start my work.
Please sent any suggestions u have for the fiberglass built and the process i just mentioned.

Don sir, thanks for your concern! sorry for later reply to your post.

welcome back Ghanshyam

Good to see you back Ghanshyam..
Building a hull from Foam( Thermocole would be an easier option)

Shreekant

Thanks a lot Maharana Sir and Shreekant Sir.

Shreekant sir,
I think that making it in Wood would be better and the other reason is that,carpentry work is going on at my place i have lots of wood to work out with and have carpenters to help me out with it to make a proper model in wood than will make a plug from plaster of paris and the FG.

Do any one have any idea what materials to be use in Fiberglassing. Which type of fiber cloth such as:
chopped strand mat (CSM) (made of randomly oriented small cut lengths of fiber all bonded together), woven fabrics & knit fabrics or uni-directional fabrics and which epoxy resins to be used??

Use light weight wood and ply for making the plug, use putty instead of PoP because it make break while handling/fiberglassing the plug. I use chopped matt. If you can access the fiberglass cloth it is better.

This thread has come alive again, thanks to Ghanshyam.

Sb_Maharana - what kind of 'putty' are you referring to? You have built some lovely FG hulls and craft. Why don't you create a build log from start to finish, outlining all the various material that are to be used. We will all benefit from it.

Regards.

@VC
The resin I am having now is more than six month old, the acc. and hardener seems expired. Last week I have tried to waterproof the rowing boat, but it is not drying and taking long time to cure.Bole to no chemical locha happening. It remains very sticky.
Will order a fresh stock this week and try to create a build log for making a fiberglass hull.
But give me little time, will upload some of the old photographs.

@ Maharana,
The Stickyness problem happened to me as well.probably for the same reason of storing it for a longer time. maybe the humidity also has an effect. I guess lesson to be learnt buy resins only that you need.. Do not stock these resins.
Shreekant

people might kill me for what i have done....
i made a faux fiberglass cowl for my mustang foamie, by layering bandages painted with araldite 8 hour...
its light as a feather and hard...
tested it by throwing it into a wall.... nothing happened..

Quote from: aniket210696 on July 22, 2013, 03:58:06 PM
people might kill me for what i have done....
i made a faux fiberglass cowl for my mustang foamie, by layering bandages painted with araldite 8 hour...
its light as a feather and hard...
tested it by throwing it into a wall.... nothing happened..

I had done the same with a car body, I used some synthetic fabric with araldite.

I am in the same sticky problem

I have put resin on the sunboard of my bootlegger for strength, but though it is seemingly dry, under the surgace it is still sticky; I found out when I tried to sand it. I blame the weather.....one full day in the sun in delhi summer and thats it

Sent from my GT-S7562 using Tapatalk 2

@Shreekant – you are right, but the minimum quality sold is 5 kgs. I use at most 1 kg per build, rest goes thicker and hard. This time instead of wasting the resin, I will use and copy max nos. of hulls and sell it at a cheaper rate. 
These are some of the pictures of my previous builds, where I have used different types material for making the plug.
1) The middle one I have used a cap, cover it with M-Seal to make a Vent.  I have used a plastic bottle to make the EDF holder.
2) Boats with complicated shape, corners and fine step cuts and where upper and lower surface are to be covered by fiberglass, I   
    preferred putty (Asian Putty) finishing. e.g. Atlas Van Lines Boat.
3) For simple hulls like Tug boat, deep V etc. PoP is preferred. 

When the position of the plug is not changed too often, less handled while fiberglassing, PoP is preferred.

This is a very good tutorial, explaining how to make a fiberglass boat hull.

Good Video...Is there any benifit of using the inside of the mold inside of fiberglassing the outside, Besides achieving the finish quality due to the colour already painted inside.

shreekant

@rooster if you do the inside of the mold, the outer part, which you look at, will be as smooth as the inside of the mold, and will be free of any uneven bumps etc that can occur otherwise, as the mold keeps it's shape...

smoothness will depend on the mold quality. I guess it has to do with the process of removal of the fibreglassed piece from the mold.

shreekant

Not only mold ,but also Type of gelcoat and vacuum bagging!