New Scratch built fibreglass/carbon mono build

[martno1fan]

Its not bad for a first attempt mate,the gelcoat issue could be anything from the temperature,moisture in the air too much or too little catalist take your pic lol.What gel are you using is it white?,tip for you try buying clear brushing gelcoat i find its thicker than the premixed stuff,i then buy in pigments to colour it with,means i only have to buy one gelcoat and i like it better than the coloured gelcoats.Some pre coloured gelcoats can be a bit wishy washy and thin too,mixing your own you can allways add a little more pigment to get a deeper colour and the gelcoat seems thicker to me.
All in all i think youve done a great job on it and im sure the next one will be even better,i dont think many who are reading this thread realise just how dificult it is to do what you have done which is possibly why more arent comenting.Dont worry about that trust me what you have done takes great skill and patience so well done.
Mart

[BondoBob]

I hope your not going to give up.I look forword to seeing your new post every day.I wish there was a spot just for mold making.This just makes me want to start building my own molds agian.

[MM28]

Thank you for showing me this webpage ! I look forward to using it.

[minigazz]

Sorry I haven't been on for a while, I am back at university now and the internet hasn't been working all week!

Thanks for all the encouragement, I will definitely carry on with the building when I get back for the easter holidays. Sometimes I think its good that I end up having to leave the project for a few months, it stops you getting too fed up with things! I was using just plain white polyester gel coat, not the clear stuff. I sometimes get annoyed by people posting builds described as 'scratch' when they have just bought a hull and put the electronics in it - I have nothing against doing this and I appreciate that it is still interesting and requires a great deal of skill, but it is not 'scratch' and can be misleading when you are trying to find out things like this!

Ultimately with this project I have learnt a great deal! I have learnt things that you can't learn without buying the stuff and having a go for yourself. I think the biggest slow down with this project came from trying to brush the primer onto the plug - the thick brush strokes took so much sanding!

[BondoBob]

Your back. Hope you had a good holiday.

[minigazz]

Hey, Im back home from uni for the easter holidays so I have a few weeks to know out a few boats and tinker around with them!

Over the last two days I knocked this one out
IMG_2973.jpgIMG_2978.jpgIMG_2981.jpgIMG_2982.jpgIMG_2983.jpg

It actually came out a lot better due to thicker gel coat layers and more sensible curing times. The only problem is that it is wayyyy to heavy at about 350grams so the next one I'm thinking 1 layer of 100grm CSM with 2 in strategic places and no use of bog mix around the base of the hatch. I didn't use bog on the first attempt and it worked fine so I'm not sure why I did it this time. Hopefully that will bring the weight down to around 200grams. Don't get me wrong, this thing is solid!

I am not sure that using bog mix to join the two halves is the best method as you end up with a lot of mess on the inside of the hull and the fibres don't actually do a lot. It may be a good idea to mix something into the gel coat to thicken it a little still though? I have managed to make it fully water tight this time though!

I have plans to make a boat with a carbon fibre lower half, just for looks more than anything. Can I simply coat the mould with laminating resin, allow it to go tacky and then lay up the carbon fibre cloth or do i need to use clear gel coat?

As for my plans to sell these things, I am not really sure if its feasible. The latest hull I am very happy with, however it does have some minor imperfections in it which I do not know if people would be happy with. With Turnigy knocking them out for under £30 its tough to compete! We'll have to see how it performs i suppose, I'll make another lighter one before I splash out on the internals. Mine are slightly larger than the Turnigy ones which I guess is a plus!

[RCKong]

WOW nice boat. Very clean and aero looking hull. If these hulls are 31" to 34" they would probably work well for racing.

[martno1fan]

The bog mix is just to glue the parts together you still should use glass tape on the inside but boat looks good
For the carbon yes use clear gelcoat and lay up as normal but be carefull not to disturb the carbon twill,you cant just stick carbon on top of tacky resin or gelcoat or it will come out looking awfull trust mePersonally unless your vacuum moulding i wouldnt do it as i doubt you will be happy with the results to be honest.
Mart
ps on a side not heres how im planning to do most of my moulding in the future once i get my moulds done.Im in the process of building a set of male and female moulds for a buisness partner in Germany as we speak.

http://www.youtube.com/watch?v=yTsXKGUdtCE&feature=results_main&playnext=1&list=PLB7DBC820D21DE8FB

[RandyatBBY]

Interesting Infusion thanks for sharing. Looks Like Mingazz is having fun good results, it is a lot of work.

[martno1fan]

The advantage of this method "resin transfer moulding" RTM over infusion is you dont need to use thinned down resins so the boats come out stronger also the inside comes out as smooth as the outside which is another plus.Another plus is no bags or extras to buy once you have the moulds so production costs come down too.
Mart
heres another video.

http://www.ecfibreglasssupplies.co.uk/t-vid_ResinTransferMouldingLight.aspx

[RandyatBBY]

OK, it is a extension of infusion with a expensive pump and inside mold. cool stuff wonder when Harbor frieght will be selling a pump???

[minigazz]

Could I get away with just using just gel coat to glue the two halves? Then attempt to tape on the inside after? It's very tight inside, that's the only problem! I'm finding that when I come to smooth the join I end up with two dark stripes separating the white of the hull all the way around - I presume this is where I haven't used enough gel coat during the layup and so I'm sanding through to effectively the fibreglass underside? More gel coat next time I think!

I'll probably forget the carbon idea then to be honest. I have seen those vids before, the results must be fantastic! Will that be using a shoebox join? My reasoning for going with the flush join was that on a boat this scale the shoebox would be far more prominent and would stand out more. Plus I was keen for the understated kind of look. Thanks for all your positive comments, always nice to hear!

[martno1fan]

Your allways going to get a seam arround the boat no matter what you use and that will most likeley need painting after,yes you can use gelcoat it works pretty well so long as you tape the seam inside.
As regards the new moulds im doing most are for a seamless join like your hull apart from the Apache which will stay as it is as theyre pretty bullet proof done this way.
Mart

[RandyatBBY]

You can make dams around the bottom with balsa strips. I use resin, cab-o-sil and pigment to make a peanut butter like substance to fill the seams. I like to use the fiber tape when I can get to it and masking tape on the outside.

[martno1fan]

Yea good tip or you could use some fibrglass sheet cut in strips,simply make yourn own on some melamile worktop or simliar surface glue these arround the inside edge of the bottom then use whatever bog you wish to join the top half,gelcoat works very well ive yet to have a hull come apart when ive used gelcoat to join hulls,seen plenty of others hulls come apart after using other methods though lol.A friend in the states has one of my Apaches he emailed me recently to tell me since hes had it 6 other apaches from elsewhere have split at the seams and his ran right over an r42 cat snapping off its plug and only a tiny 1/2" scratch on my hull and hes flipped her and barrel rolled her a few times and shes still as good as new almost a year later hehe.
Mart