link stringers to bulkhead or not

I’m getting close to the point in skinning my floor and horizontal surfaces and I can’t decide whether or not I need to link my stringers to the bulkheads where they cross paths. Is there a general rule for doing or not doing this. Not tying them in would give it the ability to flex right there which is good in some cases. I’m general though when aluminum has the ability to flex and move it’s going to crack.

 

By this do you mean that you will be laying down a tanktop plate (ie a horizontal sole) on top of the transverse frames shown in your photos?

In the first photo there appears to be a bulkhead in the far distance - or are you regarding the frames shown as bulkheads?
Are you worried about welding the longitudinal stringers to the bulkhead(s)?

Are you at liberty to disclose more details about the design of this vessel, and how large she is please?
Is she your design?

 

It’s my design. I have my own business. I’m curious about the longitudinal stringers to my bulkheads. It’s a 24/84 with a 3’ beak.

 

Yes, but it is more technical and not a simple one liner reply either.
Having said that, you're boat is small...and long.t strength is not an issue. Continuity of strength and load paths - are, to avoid cracking!

No, that's incorrect too.
Next time you fly, look out the window...what are the wings doing....solid or flexing??...and there is your answer!

Unfortunately, i see many "issues" with your design that will render/prone to cracking just as much as whether the long.t are connected to the WTB or not.
Such as:



The welds look 'sooty' too...so gas flow/temp issues.

 

Thank you Case for these additional photos - but what is a '24/84' ?
And how are you planning on 'skinning your floor'?

And thanks to Ad Hoc for the comments re the photos above.
Please do take note of these comments, even if the construction method shown is your 'usual' way of building these boats.
There is a LOT of scope for improvement here!

 

The cut outs for the floor will be rounded. What should I do different in the corners where the bottom meets the sidewall And the gussets? The 3rd bulkhead was unexpected and requested later. I had to wing it since the initial build wasn’t designed for it. I had to lose the front portion of the floor and jump back to the sidewall stringer. I figured it would be better to land it there. The floor runs won’t be sitting directly on the bulkheads. I’m going to do angle underneath and lift left up just high enough to make them lever and off the top of them. What do you recommend?

 

It’s 24 feet long and 84 inch bottom. 3/16 will be laid on top and welded below deck to the frame. The floor will have cut out strips spaced out on top of the frame and welded to the supports

 

How...now it is already in??

Mouse holes

- this is basic shipyard practice!

Same:

Doesn't bode well from the outset.

About which...too many issues at once?

 

Nice well sounding words... but I don't see much of quality control and attention to detail.
Sorry to be so harsh , but no easy way to say it. It is not pretty..

 

I’m all about improvement and growing my knowledge. By no means will constructive criticism bother me, whether it’s from a 5 year old or a 50 year old. If it’s incorrect it’s incorrect. Not being able to admit your wrong and learn why, you will never know much more than you already know.

 

That is very refreshing to hear.
Since why bother coming onto a site - for advice - if it is ignored, as the pill is too bitter to swallow?

I'd recommend you get a hold of Proboat Magazine Issue 151, Oct-Nov 2014, there is an article called - Order of Assembly, which addresses the basics of building, and also issue 137, June-July 2012 - Fabrication and Fatigue Failure in Aluminium:
Professional BoatBuilder Back Issue Archive https://pbbackissues.advanced-pub.com/

 

Ok cool man, I appreciate it. I’m going to go through and read all that. With the obvious instantly noticed flaws aside, would you join the longitudinal stringers to the bulkhead or let it ride as is?

 

They look like very stiff stringers and alredayt - as if - they are butted up to the WTB anyway.
So what ever you do, needs to address this.

You can add a FB above and add a series of bkts, like shown:


It depends upon the duty of the boat...will she be bashed and smashed about and at high speed?

 

If the stringers are box sections...and you feel confident you could snipe them back short like this:

 

I cut t bar to make gussets for what your talking about up against the main bulkheads like the ones you are referring to. I haven’t tacked them in yet those are cut for both ends where they meet the bulk head. Everything is tacked in right now. I normally get everything build and installed then go through and burn all my framing out at one time allowing cooling through each main section. This boat is not going to see much more than 1-2 foot chop at the worst. It’s a large work boat for a company that does carbon banking. They plant tens of thousands of trees along the coastlines to offset the carbon footprint these major corporations produce. It’s going to be completely open. This boat will have a 250hp Tiller steer motor haha. I have to build 2 more just like it. I gave them a good price on them and they need them fast so as far as a perfect build down to every detail, that’s not really the intended objective here. It’s get them built and get them out fast. That all they keep stressing to me. I’m a one man show so I’m getting at it.