First Rib purchased, now the rebuild starts !! - Page 2

beamishken · 13 July 2015, 22:25

What sort of nick is the Yamaha in? Must be getting on a bit![/QUOTE]

Let him get over the glass work before you start worrying him about the engine lol!!!!

That's the 421sti by the looks so less stressed than the 24 valve versions & hopefully the boats spent it's life slowly decaying while the engine remained unused

MAC1010 · 13 July 2015, 22:38

Beamishken yes its the 421 engine, replaced a few years ago now. Only just over 100hrs then boat laid up and left to fall apart round the new engine !! bad news for the previous owner but good news for me, have sold some parts that I didn't need as they are going to be replaced so the current spend on the project including the purchase price is just £4100

yam man · 13 July 2015, 22:58

Engine looks quit tidy from pics . Good luck with the build

beamishken · 13 July 2015, 22:59

That was a bargain engine alone is worth 5k I think the achilies heal is the raw water pickup which is too small but cured by fitting a thro hull scoop
I just bought a 7.4 delta minus it's engine & can't decide weather to fit a 421 I have or a merc 250 D-Tronic I have

yam man · 13 July 2015, 23:04

I would stick the yam back in it . 421 onwards is ok the pipe diameter is bigger the 420 which was only inch on the seawater side .

beamishken · 13 July 2015, 23:22

I was leaning towards the yam but I'd need to either make an adapter to fit a mercruiser v8 Bellhousing or find a yam inner transom shield as im using a bravo drive, spline is the same but rear mounts on Bellhousing are different

beamishken · 13 July 2015, 23:26

Sorry for thread drift btw

gtflash · 14 July 2015, 15:01

Please can I see this tool to take tube flange off? Intrigued

MAC1010 · 14 July 2015, 19:59

gtflash, not got a pic of the one I have but it is very similar to this.

Neil Harvey · 14 July 2015, 21:59

Very interesting to see this thread considering I nearly bought that boat.....

MAC1010 · 14 July 2015, 22:41

Today I released the temporary formers from yesterday and then made the new bulkhead, 30mm core, poly prop grid, 600g quadriaxial mat either side with 300g csm dressing cloth on that. Cut it out to suit and bed it on Crestomer 1152pa

You will see from the pics that I have ground up the hull to allow for a nice bonding angle, this will be done tomorrow but only after I have put an extra radius of the Crestomer on the joint beforehand as this produces an incredibly strong joint. This gives a large contact area for the Crestomer and also prevents unwanted sharp 90deg bonding angles that are far more prone to de-lamination in extreme conditions than ones that follow a nice radius on the joint. (this particular Crestomer was designed for sticking in bulkheads the UK's fibreglass minesweepers so that they are able to withstand multiple mine detonation without delimitation of the bulkheads, whilst not as extensive as theirs my own tests over the years using this product have produced some truly amazing results)

yam man · 14 July 2015, 22:44

Not cheap either the 1152 . But good stuff as allows for flexing

MAC1010 · 14 July 2015, 22:55

Yes I think thats why it is not widely used, but I want the best so thats what I use for jobs like that

also because of that Baders don't hold much stock anymore and larger orders of 6 to 8 kegs (my normal order as we use quite a lot of it) have to be made specially. In a test I have stuck 2 fresh sections of 10mm grp together before to form a "v" used that in the jointing face and then radius the back. Following day I went at it with a club hammer, ended up with the largest sledge hammer I could find after god knows how many hits (I remember being out of breath !!) the only thing that happened was that the edges of the laminate were starting to give up as you would expect if you just threw it round the workshop for half an hour !! but the joint itself was still in perfect condition

yam man · 14 July 2015, 23:16

I remember my mate of mine using it who's a boatbuilder.
He was bonding bulkheads , stringers / longitudinal's in with it an highly rates the stuff . But has he said being nearly £600 for a 25kg bucket not a lot company's use it budgets an all that . Looks good what your doing

MAC1010 · 15 July 2015, 22:07

So I put the radius on the bulkhead joint first thing then got on with beefing up the Tank space hull longitudinal's. The originals are 19mm plywood and the only joint between this and the original plywood deck was a bit of wet 600g mat !! unbelievable !! it probably delaminated before it even got launched !! Needless to say it needed something extra and I had some offcuts of 70mm core material already laminated in the workshop and these were destined for the bin so may as well make use of them as they are very light and provide a huge amount of strength. On top of these I sat some 74mm OD 6mm wall thickness pultruded grp box section that we have made for us as this will make a perfect landing for the new deck to sit down on 1152pa and create a really strong bond with the deck structure in that area. I ground everything up (the box section needs a real going at with 24g discs as they use a release agent as it is pulled through the water cooled former on the machine so you have to get rid of that and back to bare grp) and stuck it all down with Crestomer and put a nice radius on all of the joints. Next stage is to over laminate all of this If I have enough time tomorrow but am quite busy so not sure if I will get a chance to do that.

MAC1010 · 19 July 2015, 09:21

I have found even more water !! another 60L or so !! when I cut out a rotten bulkhead to the last sealed area of the hull out it all came. So that SHOULD be the last time I find something like that on this rib

After inspection of the fuel tank I have decided not to use it again, the basic design of it is flawed and the quality is not great. So I will build the tank into the hull structure, no chance of leaks, stronger, save the weight of the tank, increased capacity, save cost of replacement etc etc. So I ground that area up, fitted a new forward bulkhead and have put a radius on the main joints ready for laminating.

Yesterday I got the new deck board made for the area I am currently working on as shown in the pic. Also shown is a board I have laid up to make the fuel tank baffles from. You can see that the baffle board is a different colour and this is because you have to use a special resin (that I modify to make it 100% perfect for this job) So that is todays job to cut all of those out and line the compartment with a resin rich layer.