Pigeon_Droppings2
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Could you buy 9mm and then just remove the top layer maybe?
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Bullet2012
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The owner is quite happy to pay £91 for a sheet of 8mm but baulks at £380 & im not surprised.
The other issue is quality, the boat is very well built of top quality known brand ply, putting cheapo unknown far eastern ply in it isnt an option. I have seen too much of it fail.
Only a year ago a bloke in a local yard was building a catamaran out of plywood, He got a big consignment of ply, guaranteed quality etc etc.
Built one hull, left some offcuts outside in the rain, one month later they had delaminated. He got his money back on the ply but still had to destroy one substandard hull & start again.
I have solved the problem for this time round, I found a bigger piece of good 4mm ply & have epoxied two bits together!
The other issue is quality, the boat is very well built of top quality known brand ply, putting cheapo unknown far eastern ply in it isnt an option. I have seen too much of it fail.
Only a year ago a bloke in a local yard was building a catamaran out of plywood, He got a big consignment of ply, guaranteed quality etc etc.
Built one hull, left some offcuts outside in the rain, one month later they had delaminated. He got his money back on the ply but still had to destroy one substandard hull & start again.
I have solved the problem for this time round, I found a bigger piece of good 4mm ply & have epoxied two bits together!
Pigeon_Droppings2
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Still making progress on the boat...keep forgetting to take pics (too busy itching!!!).
A lot done...still a lot to do. Lots of folk looked at it and told me I don't need to brace it...but I'm too chicken plus it's my head that's sitting right over the hull prop when I hammer out the last bulkhead!
Pic is part way through the bracing.
A lot done...still a lot to do. Lots of folk looked at it and told me I don't need to brace it...but I'm too chicken plus it's my head that's sitting right over the hull prop when I hammer out the last bulkhead!
Pic is part way through the bracing.
Pigeon_Droppings2
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The other side is at the same stage...so just that last bulkhead on the right in the pic to come out. I'll replace one at a time....bit nervous if I'm honest.
Pigeon_Droppings2
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W.olly
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Hi kida, sorry not seen this much and whizzing through.
A few things spring to mind to help if you havnmt already done all your work, Marine ply is good when laminated, it will not delam for many many years it sealed well, poly resin is good enough but epoxy is dogs do dars if you give that on top coat. poly resin does not stick to epoxy.
Nidaplast is good but i have always used Polyurethane sheets, a lot cheaper aswell and easy shaped.
A couple of my old boat projects if any good to you for ideas
I dont have a clue if this link works but worth a go.
A few things spring to mind to help if you havnmt already done all your work, Marine ply is good when laminated, it will not delam for many many years it sealed well, poly resin is good enough but epoxy is dogs do dars if you give that on top coat. poly resin does not stick to epoxy.
Nidaplast is good but i have always used Polyurethane sheets, a lot cheaper aswell and easy shaped.
A couple of my old boat projects if any good to you for ideas
I dont have a clue if this link works but worth a go.
If anyone is interested i will update bit by bit the progress of it, i started this a bit ago but this is the start of the madness
Yes it is a bit shall we say ruff, but i like a bit of DIY to keep me busy
Not to dwell on the past, after a bad last 18 months or so and ending up boatless and very little finance wise to get started back on the boating scene we found this wee cruiser on the good old fleabay,We were after a bigger boat but at the £150 this cost towards what we was looking at spending we got this, good thing is its only 9 miles from home where we could of done work on...
Yes it is a bit shall we say ruff, but i like a bit of DIY to keep me busy
Not to dwell on the past, after a bad last 18 months or so and ending up boatless and very little finance wise to get started back on the boating scene we found this wee cruiser on the good old fleabay,We were after a bigger boat but at the £150 this cost towards what we was looking at spending we got this, good thing is its only 9 miles from home where we could of done work on...
Hey i am at it again 
I have been looking for another project for a few weeks now, infact not long after i finished Khashoggi. I looked at many and thought of many to buy from part done to shells again and start from scratch, sea boats to river boat to canal/river boats.
I found some boats that could be made into crackers but they were asking stupid money, i mean a 37 foot GRP MS bare hull ( once ripped out ) and engine for £5k.
Anyway after a good talk with T i decided to get another river/canal boat, T is not mad on going to sea and as she is...
I have been looking for another project for a few weeks now, infact not long after i finished Khashoggi. I looked at many and thought of many to buy from part done to shells again and start from scratch, sea boats to river boat to canal/river boats.
I found some boats that could be made into crackers but they were asking stupid money, i mean a 37 foot GRP MS bare hull ( once ripped out ) and engine for £5k.
Anyway after a good talk with T i decided to get another river/canal boat, T is not mad on going to sea and as she is...
May the itching will have stopped by the time you are back.
Then you can top up the itch factor again.
Re Plywood, most so called marine ply today is garbage & its a lottery as to if it is any good. I mentioned Robbins Elite in an earlier post but with a virtual monopoly on th stuff they are expensive as i found.
Cored GRP bulkheads are an option & Wolly mentioned Nidaplast, that is one i havent used so cant comment on it. Some people use Polyurethane sheet like Celotex, the advantage being its relatively cheap & available anywhere. Problem as a core is it low density soft & has very little shear strength this means the grp skins each side become detached easily & then the core isnt doing its job, its akin to chopping out the web of an RSJ it goes floppy.
Better cores Are PVC such as Airex but it isnt cheap & better suited to Epoxy. Most cost effective one i have found is PET foam which is the same stuff that plastic drinks bottles are made from, Its also available in recycled form & works well with Polyester, vinylester & epoxy.
If laying up a panel it can be done easily on a melamine faced sheet of chipboard or sheet of plateglass if you have a bit big enough, Three coats of wax & you are good to go. You can hand lay up such panels, For ultimate strength & lightness vac bagging is used with epoxy but costs soar rapidly!
Cored GRP bulkheads are an option & Wolly mentioned Nidaplast, that is one i havent used so cant comment on it. Some people use Polyurethane sheet like Celotex, the advantage being its relatively cheap & available anywhere. Problem as a core is it low density soft & has very little shear strength this means the grp skins each side become detached easily & then the core isnt doing its job, its akin to chopping out the web of an RSJ it goes floppy.
Better cores Are PVC such as Airex but it isnt cheap & better suited to Epoxy. Most cost effective one i have found is PET foam which is the same stuff that plastic drinks bottles are made from, Its also available in recycled form & works well with Polyester, vinylester & epoxy.
If laying up a panel it can be done easily on a melamine faced sheet of chipboard or sheet of plateglass if you have a bit big enough, Three coats of wax & you are good to go. You can hand lay up such panels, For ultimate strength & lightness vac bagging is used with epoxy but costs soar rapidly!
Pigeon_Droppings2
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I found this out the hard way after I had bought the ply and cut it to size
.I happen to Google the stamp info...the stuff isn't what I thought it was!
I now have the correct CE code for exterior grade ply so will look for that.
Pigeon_Droppings2
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Cheers for the info...I'll take a look. I'd really prefer not to use ply but I'm amazed how few alternatives I'm finding!
East Coast fibreglass, Core materials, PET 15mm is slightly cheaper at £39 for 1.2 x 1m sheet & for the application probably better. It does not soak up water at all. Avoid polyurethane at al costs as it soaks up water like a sponge, I have shoveled enough of it out of boats to know this!
For a good bulkhead i would use 15mm pet foam with each side 1 layer of 100gm chopped strand mat followed by 1 layer of 450gm Biaxial with 1 layer of 100gm CSM on top. Using Biax cloth will save you a lot of resin.
CSM needs 2.5 times its own weight in resin to wet it out , Biax is 1:1 ratio, & far stronger & stiffer so a big saving in the most expensive bit.
, https://www.ecfibreglasssupplies.co.uk/core-materials,
For a good bulkhead i would use 15mm pet foam with each side 1 layer of 100gm chopped strand mat followed by 1 layer of 450gm Biaxial with 1 layer of 100gm CSM on top. Using Biax cloth will save you a lot of resin.
CSM needs 2.5 times its own weight in resin to wet it out , Biax is 1:1 ratio, & far stronger & stiffer so a big saving in the most expensive bit.
, https://www.ecfibreglasssupplies.co.uk/core-materials,
Pigeon_Droppings2
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Think I'm going to stick with ply with this one...the boat isn't a keeper so I reckon ply will be easier.
Reason it isn't a keeper is that it's a fixed keel which makes launch/recovery more hassle. I'd have preferred a drop keel if I had the choice again.
I looked at the PET....I think that's definitely the way to go...it's a more permanent solution where as the ply will need redoing in future (but not by me!!)
Reason it isn't a keeper is that it's a fixed keel which makes launch/recovery more hassle. I'd have preferred a drop keel if I had the choice again.
I looked at the PET....I think that's definitely the way to go...it's a more permanent solution where as the ply will need redoing in future (but not by me!!)
W.olly
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There is nothing wrong with ply at all. Even hardwood ply is ok when laminated on. I ja e worked on boat that are 50 years old and the ply core is still good. What ruins it is when folk do jo s and do t do it properly. Like drill holes in it and do t resin the core .
Sticking screw in and not sealing them.
Ply is fine.
Pigeon_Droppings2
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W.olly
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Did the ply have the BS 1088 on it.
I have yet to get a true
Marine ply that has voids.
Pigeon_Droppings2
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Quite amusing...the bit with the void also has their stamp on it!
I really don't buy much of this stuff so maybe I just got lucky!
Maybe I bought the wrong stuff...does say marine ply (left).
I really don't buy much of this stuff so maybe I just got lucky!
Maybe I bought the wrong stuff...does say marine ply (left).
Bullet2012
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Pigeon_Droppings2
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Cheers
