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hardcrab
05-28-2006, 07:23 AM
I have two sets of stringer gussets on each side of the engine area. These have been replaced in the past in " close enough" locations (that don't even match).

Can someone please tell me the proper location where to re-install new gussets ? I've used the top edge of the stringer and starting at the transom as a measuring reference.

It has been my assumption that the two forward gussets line up with the bulkhead panel just forward of the engine; and the two rear gussets attach in the area of the motor mounts. The idea would be to effectively box in the structure (?)

Thanks in advance for looking for the tape measure.

MOP
05-28-2006, 08:04 AM
Check Jamies post for a general idea, he may pop in with the measurements.

Saga of the "Red Mistress"
http://www.donzi.net/forums/showthread.php?t=43442&page=3

Posts #37-38

Phil

hardcrab
05-28-2006, 08:23 AM
While I'm at it, I'll ask the question .........

when installing stringers / bulkheads / gussets ; is it a good idea to NOT have a tight fit of the panel to the FG hull IE ; letting the glass layup dissipate the stress and flex ?

Greg Maier
05-28-2006, 08:57 AM
HardCrab,
The stiff stringer core (plywood, COSA, etc) should not touch the fiberglass skin. A low density foam shim should be in between the skin and the core. This low density foam should be cut to allow the fiberglass that you encapsulate with to butress out away from the coring where it meets the skin. www.boatdesign.net is a great source of info for this.

hardcrab
05-28-2006, 09:31 AM
HardCrab,
The stiff stringer core (plywood, COSA, etc) should not touch the fiberglass skin. A low density foam shim should be in between the skin and the core. This low density foam should be cut to allow the fiberglass that you encapsulate with to butress out away from the coring where it meets the skin. www.boatdesign.net is a great source of info for this.
howza 'bout 100% silicone joint between panel and hull?

MOP
05-28-2006, 09:47 AM
You are thinking about what they call hard spots, true I feel you should light chamfer things that helps. I have heard variations some builders do loose fit shim bulk heads off the tab them in place and finish the laminate after the tabs cure. I side jobber for a manufacturer that stapled rope on the edges of bulk heads and glassed. What little I did on the Beast I lightly chaffered the parts then set them into strips of wet mat and finished glassing, the pro that did my stringers set them in a paste the same stuff that Hustler boats uses. He said before they used the bedding paste they were cracking hulls right under the stringers. I have wondered about setting parts in place with 5200 and radiusing it so the glass would gently bend from the part to the hull. I know radiusing relieves the stress squared joints will break over time.

Phil

Greg Maier
05-28-2006, 12:20 PM
I don't know about silicon caulk. Like I said, I would go on the boatdesign forum. Lots of hard core fiberglass guys and boatbuilders on there.

bobwpe
05-28-2006, 04:41 PM
Hi Hardcarb,
I'm currently restoring a 1973 18 2+3 and the measurements for mine are 22 3/4" from the transom to the aft edge of the rear gusset and 45 1/4" to the aft edge of the forward gusset. We also added a pair of gussets further forward although I can't get in there to measure the exact distance but you get an idea from the picture.
When I got this hull it was in surprisingly good condition for its age and the only cracks in the gel coat were spider cracks on the bottom directly below the forward edge of the stringers. We glassed in some filler pieces to fair the stringers into the hull to prevent these cracks from re-occuring in those locations. I'm not sure if it will do the job, but I know it will help.
Hope this helps.

Rootsy
05-29-2006, 08:37 AM
my 66 18 had NO gussets... i put 3 per side on roughly 30 inch centers. the 2nd one falls on the first bulkhead line.

i bedded mine in fiber reenforced polyester putty... then filleted around.... also cut the corner out where the bottom / stringer joint is.

in hindsight i SHOULD have used Plexus to glue them to the bottom... you'll delaminate the glass before the plexus fails... and depending on which version you use it has some good elongation before failure properties... (ie some elasticity)...

Greg Maier
05-29-2006, 09:43 AM
Rootsy,

What do you mean when you say that you cut the corner out where the stringer meets the hull?

Scott Pearson
05-29-2006, 10:56 AM
Here are some shots of the string and gusset work on my 1968 18. Hope it helps.

hardcrab
05-29-2006, 12:20 PM
Rootsy,
What do you mean when you say that you cut the corner out where the stringer meets the hull?
I assume he means a drainage hole in the base of the triangle.

everybody has been great inspiration , thank you.

I think how i'll handle this is to end up with 4 on each side, one set at the forward engine bulkhead, one set at the rear gas tank bulkhead, one set half way between those two and, then at the motor mounts.

NOW ............... when I install my new transom panels, do I cut the stringers back or, notch the panels around 'em ?

I'm losing too much fiberglass dust, gotta go grind some more ..........

Greg Maier
05-29-2006, 03:28 PM
Scott,

Can you send a larger version of the first picture if you have it? It looks like you extended the gussets almost up to the gunwale. Is that the case or am I just seeing things?

Scott Pearson
05-29-2006, 06:44 PM
Greg,
Yes I extended them up. Stiffens the hull sides some.

Hardcrab,

Dont cut the stringes:eek: ....notch the transom wood or stay inbetween the stringers with the wood.

Rootsy
05-30-2006, 08:20 AM
is it true that oranges crates were use for wood in the pumpkin??
that is just incredible that one shot you expect to see a tech in a positive pressure suit like they have in the bio hazzard clean rooms
the pumpkin is truely amazing and it looks like she will have a candy apple sisiter up in MI nice work guys :)


more like a redheaded distant cousin or something... and it's Lucan Red man... no candy apple... this ain't a mustang :biggrin: