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Re: Richards gt 27

Posted: Thu Feb 25, 2010 12:51 pm
by Daddy
yeah, what he said. :D :D :D :D

Re: Richards gt 27

Posted: Thu Feb 25, 2010 6:19 pm
by rcihard
Thanks guys, I will continue to post updates as able. I too want to see one of these boats for real :)
Will start joinging bottom and hull lengths this week now that I have the extra room added to the shed.
Have all but finished the d5, now have to find a spot to store the thing while I build the barge.
Thanks again for the positive comments.

Re: Richards gt 27 - me too!

Posted: Wed Mar 03, 2010 3:55 am
by rwatson
Just bought the plans for a GT27 (metric Version). I aim to have it finished in 6 months.

I thought the sheet showing the panel nesting could do with a lot of improvement. Did you have to have a think about that very much ?

Re: Richards gt 27

Posted: Wed Mar 03, 2010 6:04 pm
by rcihard
Hi rwatson and welcome aboard.
Yeah there are quite a few holes in the plans. The nestings are missing a couple of sheets. Be carefull with the transom layout i.e. the bow transom is two pieces laminated and the bow pieces for the bottom panels are cut from these sheets as well, this is not stated in ther plans. Also there are many measurements missing from the station and bulkhead drawings, if you do a search in the Power Boats section you should find my many questions and some answers from jacques about these.
I am building the stitch & glue way i.e. from the keel up, I noticed that previous builders have used the jig method (all though I have not found one completed GT27 yet). still glueing stringers together and traonsom. Just stuffed my back up so things are pretty slow at the moment.
Where are you :?: :?:
Hope you post lots of pix, I am trying to be ready for xmas (our summer here) so if your plan is six months you will be way in front of me and I can keep track of any problems you run into and hopefully avoid them :D
Start a thread on your build :!:

Re: Richards gt 27

Posted: Fri Mar 05, 2010 4:45 am
by rwatson
Bad news about your back. So many boat projects get slowed by health problems. Hope its better soon.

I am in Melbourne at the moment, but will be in Tasmania within two months, where I need to organise a shed and all that stuff.

I have been following your questions with interest, and you picked up a few things that wouldnt have occurred to me.Thanks for the warning about the 13 mm ply bits not shown.
I was more puzzled by the Nesting showing the cross members between the stringers being shown in one piece, Surely they have to be cut to fit between ? Unless they are 'cross joined' like a carton, to proide alignment of course ... I had better check the online boatbuillding tips again.

I have a few plan changes in mind myself - and I think your cabin arrangements would suit me better also.
That 'bolt on' motor bracket seems a waste of space. I am thinking of continuing the main hull stringers back out the stern transom, and making them part of the motor support. I think I will continue the hull bottom flush as well. Seem silly not to get a bit more planing surface for the same amount of material.

I plan to build the hull using a 'nest'. Basically, it's the 'right way up' method, but with side and bottom supports at strategic intervals. I saw the Sam Devlin video, and read his book several times, and I think the free standing 27ft hull would be a nightmare to do without decent framing. The weight of carting 30ft of 10 mm plywood around the workshop would be asking for trouble.
I will keep an eye out on your progress, and get a Post going when I get something worth showing done. Cheers for now.

Re: Richards gt 27

Posted: Fri Mar 05, 2010 6:59 pm
by rcihard
Thanks - Backs getting better, just taking its time.
Re the cross members (called floors in boat building or stations or frames on the plans) these are checked out as are the stringers so that you do get the egg crate formation.
I am planning on setting up a basket mold of sorts as well. I agree that lugging around 7-8 metre lenghts of joined ply is going to be a hassle (if not impossible). The building tutorials will show you different set ups and explains the framing and stringer joining.
Like the idea of continuing the stringers and bottom and hull sections, wish I had thought of that but I have cut and glued my stringers (thats how I did my back :oops: ). I would check loading capacity though, maybe ask Jacques.
BTW - The 10 mm ply nestings are also missing one sheet.
Tassies a great spot (some huge trout :lol: ) where do you plan to use the cruiser :?:

Re: Richards gt 27

Posted: Sat Mar 06, 2010 1:32 am
by rwatson
Good to hear you are on the mend over there.

Thanks for the tips - I will make sure to note them. I dont think the egg crate idea is great on this boat. i will set up a jig and make sure everything is square, and cut the cross beams in half to separate the stringers. If we need to do 200mm stringers for strength, there is no way I am going to cut out a 100mm 'slot' just the make sure the cross beams are square. Good heavens, the while idea of plywood is to use the wood grain for strength.

Because I am an invetarate 'fiddler and improver' I will probably have more crazy ideas besides that one.

As it is, I have posted the outboard pod idea on ... thread&f=3

I have been a member of that forum for a while now, and uploading pictures, answering etc is quite a lot easier than on this web site. I posted a picture of my planned mods for discussion - if you get a chance to look, feel free to comment - and DO post pictures of your progress too.

I plan to use the boat around the Derwent River estaury, and down the D'Entrecaseaux Channel - in fine weather. There are miles of the best cruising waters in Australia. I imagine myself pulling up on the banks of the Huon River in the summer, chucking a fishing line over the side .....

That gives me another idea - a cutout, drop down bow section (like a landing barge) that can serve as an easy walk down to the beach, or over to the river bank, or just to handle the stuck anchor (like a bowsprit)
Keep up the good work over there :-)

Re: Richards gt 27

Posted: Fri Mar 12, 2010 7:21 pm
by rwatson

Re: Richards gt 27

Posted: Fri Mar 12, 2010 8:42 pm
by TomW
We have discussed building your own platform many times on this forum. Up to about 20-25HP it is okay. Once you go above that the forces involved by the motor and water make it more difficult to safely build your own platform. At some point you will need to use carbon fiber and vacumn bagging to attain the needed strength. Jacques will not recommend doing it yourself and will not support doing it.

Generally it is easier to buy a bolt on platform that has been proven and tested, rather than take a chance on building a platform that may fail on your boat.


Re: Richards gt 27

Posted: Sat Mar 13, 2010 9:23 pm
by rwatson
I hear what you say there, R, but I am a bit confused.

The design description says is " At a displacement of 5,000 lbs, a 90 HP will bring her to plane with max. 25 mph in calm waters. If you want her to plane regularly, a 125 HP or more is recommended."

Maximum HP on the plans 'as is' is placed at 125 HP.
...... so I am not sure where you got the maximum figure of 25HP from.

Even so, anything 'bolt on' will be relatively limited for maximum strength. You cant buy market 'bolt on' outboard motor brackets for anything more than 15 HP, that I have been able to find. As I envisage it, extending the stringers (all four of them) to create a 'power pod' effect, should in my mind make a vastly superior extension to the hull, three of four times better than the current plans.

At the moment, I am only planning on a 50HP, and a small 8HP auxilliary. However I would expect that (weight permitting) we could mount two 90 HP without worries on the improved build.

It may seem a bit bold to divert from 'planned' specs, but the notation on the plans "All out Plans are provided AS IS. The designers disclaim all other warranties, expressed or implied, including merchantability or fitness of purpose"

For $100+ for the plans, I consider I am just covering time and trouble of doing the bouyancy calcs, structural calcs and concept, and I wont be relying on any "warranties" from the designer.

I am also relying on a bit of experience of boats this size over the years, and hoping I wont end up in too much trouble. Thanks for the input though, Its good to get a voice of conservatism speaking up when thinking of 'alternatives'.

Did you get you boat in the water yet ? I am really looking forward to hearing about your project, not matter what stage its at.