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hardcrab
05-11-2004, 08:46 PM
undefined i am interesred in hearing about anyones experience regarding top deck removal/gas tank replacement.... i have seen the page on this sites tech section and am curious how rigid or flimsy the deck may be to handle when the wood core has rotted out, i am planning on building a cradle to support and maintain it's correct shape during surgery...... i will document this project and post pics for the next guy............ any imput will be helpful

Fish boy
05-13-2004, 08:13 AM
Hey Hardcrab,
welcome to the donzi registry! I ahve not done it myself, but I have seen several posts from other members who have done this. In fact, I think CDMA does it every time he waxes his boat ;)

I am sure someone will be a long soon with some input. You alos might want to try the archives, I seem to recall a few articles on this and a some pics to boot.

Good luck with your project,


Fish

mattyboy
05-13-2004, 09:09 AM
hardcrab,
I'm not sure about the 18 ski locker?? and just how rotten your core is?? but on my 16 the back hatch area was not a problem but the nose and the ski locker you want to support but not too much !!
There are a few menbers that are in process of this with 18's on the board, and a few that have done a re core job.


Matty

Morgan's Cloud
05-13-2004, 09:29 AM
Crab ...

Just before I removed the deck on my St Topez I posed the same question.. although rot in the deck was unknown/not an issue at the time. The question was directed 'generally' not specifically to this model. It would seem from the feedback ... or lack thereof, that an answer specific to my model was sought after when it was'nt.

Although I've not done any others before I can tell you that it was a snap. Have a few burly friends on hand.. I had six although four were all that were needed. When everything is unfastened/cut loose just pop her off and place on your pre-made jig/support system.

I was petrified that the thing would be like handling a large Jello sheet but it was actually rigid enough to be momentarily placed on it's side... NO PROBLEM !

Hope this gives you a confidence booster ...
Now about that gas tank ...... :biggrin:

S

hardcrab
05-13-2004, 01:55 PM
thanks for the feedback guys, yeah, i'm planning on lifting the ski locker out with the deck by means of a sling, since the fasteners need to be cut out, and i'm doing this deal as gently as can be. the wood core is missing / gone / vamoose and the deck wobbles like paper. i feel confident that all can be replaced as new, ,, maintaining original shape is only concern, my impression is it should be able to handle well enough.................. keep those thoughts flowing!! :bonk:

Greg
05-13-2004, 04:39 PM
Before I removed my deck I fashioned a 2x4 brace from the bowlite to the transom. I connected from above thru the hole for the bowlite and in the rear thru the hole where the lifting ring was. This kept the nose and the motor compartment area from flopping around. I had three people per side. Don't let anyone get too far in front of or behind the interior area, we were shoulder to shoulder on either side of the interior. Best of luck to you.

boatpimp
05-17-2004, 04:15 PM
I, too, will be attempting to recore the deck on my ski sporter. I am having a tuff time finding info in the archives. I really just want find a pic or two of someone's jig built to avoid deck distortion. Or a better written description. Cananybodyhelpme?
Boatpimp. :confused:

Lenny
05-17-2004, 04:49 PM
Here is an "idea" of what I did in the past to support the deck. unforntunately I can't find the disc with these pics on. Anyways, this is the concept and you "scribe" while the deck is on the hull still to get an accurate shape. The 3 longitudinal "stringers" are scribed to the deck, first the center one, then one on either port or starboard. Then make the other port or starboard one from a copy of the other. I then took a laser builders' level on the shop floor, and "shot" the line from one side of the boat. As I cut it off on the line the laser projects to the next plywood stringer. After doing this three times your done. Then I joined then together using a sliding joint concept for the port to starboard connections. The amount of them is up to you. Just provide enough support so the deck doesn't move once upside down. I found 30" was an ideal working height to play with. Here is a pic of the concept.

http://www.donzi.net/forums/attachment.php?attachmentid=2721

Scott Pearson
05-17-2004, 05:21 PM
Lenny.....Step away from the brown acid.....put the pencil down slowly.... :)


(NJ)Scott
LGDCC

Lenny
05-17-2004, 05:32 PM
It was Crystal Meth, :D :D :D ,...and Acetone, not Brown Acid.

I think I left my pipe at Yasgurs' Farm

Seriously, this worked great once you turned it over. Center stringer was full length and port and starboard were close to that. I Scarfed two plys together for the length. Can't find the disc, I tried.

boatpimp
05-18-2004, 08:41 AM
Lenny, I appreciate the drawing, nice work. So, I assume the jig is not attached to the boat? You just build on the deck to line up with the scribed lines, flip the jig on the lines on the floor, then flip off the deck and line it up on the jig? Then we re-core the sucker, and it'll have the same shape as before it was separated from the hull? Sounds fairly simple... :boggled:
Boatpimp.

Lenny
05-18-2004, 11:04 AM
uh huh, it just rests in the cradle, no attachments. The removal and support and flipping of the deck will require 4 people so as not to break or crack the forward section. The cradle, also lets you "pressurize" if need be with a pole to the ceiling some sort of formed shape that you might require to place the Balsa and keep in down or reshape areas of the deck.

A trick with the balsa, and it works great, is to cut all your required shapes first, and them using an old 45 gallon drum, you bend it over the drum and soak it well, very well, and then flip it over and soak it very well again. It ensures a good resin transfer prior to placement into the coring area. Some people recommend a bedding compound for the balsa to lay into, I have a few gallons of it but haven't tried it in this manner. That is up to you. You also have to lay a mat in first (1 1/2 oz or so) , then the Balsa. The scrim side goes up, facing you. Continue to wet it out, with a brush or whatever until you start to see it puddle on top. This indicates that the end cells of the balsa are full. Let this kick. Then once it is dry, you will need to either putty the edges where it runs out into the outside deck perimeter OR when you precut the shapes you put a 45 degree bevel or filet in it. This is required to allow for you to be able to lay up the next layers of mat/roven over the edge. On top of the putty'd or radiused now kicked balsa, you should put down an 1 1/2 oz mat (CSM) and then an 18 OZ roven. If the roven wants to stand up in the putty'd, radiused, area just place some strips of 1 1/2 oz mat down. It will hold the Roven down.

If you have "dimples" in the deck, you will have to locate them on the underside and build something to push it back into shape. This is where a pole to the cieling and downward pressure into the cradle works well. Wax paper can be applied anywhere where you want a release in the future. eg:, a small piece of wax paper, a small piece of 1/4" ply on top of it with a pressure pole to the shop cieling. Once it has kicked, remove the pole, lift up the ply and peel off the wax paper. When you scribe the longitudinals, they should be smooth and exhibit a smooth arc. You do not want to scribe to any areas that are depressed and recreate the same problem only this time re-inforced. I am quite sure you don't have as much of a beast as I did. :rolleyes:

Do not run out the mat/balsa/mat/roven into the area of the sheer where the deck attaches to the hull. The shoebox joint will not fit if too much material is deposited there.

Have fun :D

boatpimp
05-18-2004, 12:33 PM
Thanks,
I believe I'll be using Nida-Core, as I can get a good deal on it, and won't have as much wetting out and such. Also, the pole/cieling trick sounds good. The top of the deck is straight, so no trouble there. I will also replace the 3/4" strip around the top of the hull while the deck is off, do you foresee any distortion problems there?
Boatpimp.

Lenny
05-18-2004, 02:39 PM
No, and when you replace the rub rail, (if you are with new stuff or re-using old) a lot of people prefer Stainless machine screws and washers and nylocks over the plain screw scenario. It would be pretty hard to distort the perimeter with the tiny 3/8" x whatever piece of wood. Mine were mahogany (Phillipine, ribbon grain , not Honduras) I would glass it in against the outside of the hull as well as run a piece of glass on the inside over the top of it as well. Mind you, if you ever have a hard dock landing or collision it will be a bear to remove and fix. Mine was "tabbed" in a few places and it was rotten. You could just pull the glass off of the hull where it was Tabbed.

hardcrab
05-18-2004, 04:52 PM
thanks for ALL the great thought on the project.......... lenny's cradle idea sounds fine but it's 180' different from my approach, which was to frame to the conture using dimensional lumber. basically, 2- 16' stringers are used to attach 2x10 crosspieces that have conture cut 2x4's supporting pressure points, being careful to maintain surface contact, and not create dimples. i have used wooden blocking against the interior openings, [hatch, cockpit] to lock the deck in place - NO shifting..........next step is to lift said apparatus on to well placed cinder block pillars, ............the deck is ready to lift as soon as cradle is in place....................