Swain BS_36 Stability curve

No, you don't understand. They're actually super-strong because those longitudinals are under tension and the tensile strength of A36 steel is 60K psi so the curvature and the longs make a sort of buttressed arc-ish type curve that can't be dented even if you crash it into a barge at full speed.

PDW

 

God , that is pure crap
I do not understand?
Christ I designed and built so many steel and al boats
<removed>

 

Crap:!: Im with Dean on this.
This is the type of argument we would expected from BS. A silly flatbar stringer means nothing if it is not supported along the way like for instance some sort of framing.
For stringers to work, you need to calculate the stringer size according to set parameters for the loads to be imposed upon, plate thickness and unsupported panel lengths. Spacing of stringers are critical and it all boils down to scantling rules in the end.
This is something BS cannot fathom or understand, let alone calculate.

We have all seen the flimsy construction detail on pictures of BS boats and here is a link to the boat in question, http://www.boatdesign.net/forums/classification/transverse-frame-calculation-32584-27.html post #401 and it is no surprise it would ding that easily. Everyone is predicting this ever since the time of the BS bang.

Here is a picture of a Roberts FRAMED boat sandwiched from the side and look at the damage.
The claims of BS boats just glancing away with no damage after being T boned of the side is utterly rubbish. If this boat looks like this, image yourself what that the empty shell tin bins of BS would look like...
And this is what BS has to say on this in the link supplied above and I quote;

Only the very foolish would believe such a foolish statement made by a supposedly professional "designer" and this type of false claims borders on criminal.

 

LOL, come on, "Dean" & Wynand, PDW is joking(aren't you?). At least that's the way I read his post. That photo of MOM that I posted is clear indication of how easily a boat lacking support could crumple. Of course, now Brent has to come back with his, "If that boat had had frames, the shell would have been torn adjacent to the frame..." mantra that we all know so well! Personally, I found PDW's post amusing.

 

So did I. Peter: What a perfectly good way to sum up the catechism from the great book of BS nonsense (but no need to say it twice). Wynand, I thought you would know sarcasm when you see it!
Regards
Walter

 

You so right I walked straight into that one - kudus to you PDW

OTOH, Im so pissed with BS's BS trying to subtract or side stepping the issues at hand by raising my building material preference - which incidentally has no relevance in this thread - in nearly every post he made.

But perhaps my reply and pic with reference link to the Transverse thread will get BS to shut up with his pointless ramble as we are really tired of that...he is like an old scratched gramophone record that's stuck.

 

Boy,you folks get a lot of mileage from a tiny picture....What "dent".It looks to me that this is the result of the two half-hulls being put together...the curve in the edges was wrong and caused the concave there.Some bad lofting onto the plate.
and the one on the beach ...where's the skeg?-do you think a boulder taller than it is thereabouts and made the curve pictured?I don't.
Funny,it didn't occur to you boatbuilders...

http://www.boatdesign.net/forums/at...5d1305523858-swain-bs_36-stability-curve-.jpg

http://www.boatdesign.net/forums/at...7-swain-bs_36-stability-curve-slideshow20.jpg

 

Or, maybe, you don't know what you're talking about:
From: http://www.sv-mom.com/2008.html

"It’s Saturday @ 2 AM.
Still hearing the huge crash in my head of when I drove MOM up on the rocks yesterday. The horrible grinding and swift halt over the smooth water still haunts my head until it hurts..."

Gee, the same photo as already posted goes with this story, as well as this one:

 

Interesting
This was not Evan's first build. With the dents between the rear keel support and engine web. Care to explain how it would even be possable to cut the plates wrong and get local dents like that ? And if you go back and look at the construction photo's every thing went together smooth and fair.
Tom

 

Sorry guys, I simply couldn't resist trying to summarise the BS posts & style.

Here's a shot of the inside of my hull. You will notice that I really don't believe in using transverse frames, what a total waste of time & steel.....

I need to do a bit more welding in there in spots but the plate is fully welded inside & out to the deck edge pipe, 20mm chine bar and the keel. All plate butt welds are done both sides, ground back before the 2nd pass. I cut some coupons and they all showed 100% penetration. It's not going anywhere and the bow would cut a BS36 in half.

PDW

 

I just looked at the build pix and I agree, those dents weren't there then.

My uninformed guess is the bilge keels pushed up at the back from the front impact and overcame the magical convex reinforced tensile strength longs curvature and pushed the hull plate in.

PDW

 

"None the worse for wear with a bottom scrubbed. WE are so blessed with such an amazing, strong boat. Lucky us ! Just stood there at this sick angle, for the keels were just at the rock, so she settled way low until it sunk down to the back skeg."

 

I agree that they were lucky if they didn't punch a hole in the hull. But whether it was a result of that incident - probable - or another, the fact remains that the boat has sustained damage, as evidenced by the photo.

So, the speculation that it may have happened by that incident is far more probable than, either;

Or;

So, while I would commend you and Brent on your abilites to deny, deflect & defend the design & construction of these boats in so many discussions, once again, the weight of probabilities are not in your favour, and the photo supports the speculation that the boat was damaged as a result of the discussed incident. But, you could always contact Carl Anderson or Evan Shaler & ask, or have they been ostracized, as well?

Specifically, as to your own contention as to how the hull anomalies may have occurred, In view of the construction photos on the MOM website,
it is about as valid as the stability curve you presented to begin this thread, iow, not valid, just more BS.

 

Oh,well,if Brent says there's a dent and why,My mistake,I missed that bit in the clutter.It looked a lot like a "stitch'n glue" mistake. I've made that mistake,where the pattern didn't translate to the material so well...

so,a recap: Home-Builder goes against designer Brent's plain advice,Owner consquently tips boat at 45? degrees onto her skeg-supporting what?70 percent of mass there per 45degree tilt?- and dents boat slightly at this "weak" spot,but Owner considers it of no consequence...I see.
...and,ah, you think this is an argument AGAINST these boats?

 

"Slightly dented"?!? That thing's wrinkled like a Sharpei's nose.

If you consider stitch and glue mistakes of that magnitude to be routine, your boats must be an interesting sight indeed....