Scrambler update

Steel and aluminum boatbuilding. See: "Boatbuilding Methods", in left-hand column of the Home page, for information about alloys.

Moderator: billy c

eurof2
Posts: 2
Joined: Tue Jun 13, 2017 1:17 pm

Re: Scrambler update

Postby eurof2 » Wed Jun 14, 2017 4:30 pm

Kevin,
Thank you for your answers on here. And for all the extra information. I really appreciate it.

As to the location of the bow piece, after talking with Gayle from GlenL I finally realized it was a mistake on my part. The dimension was turned perpendicular to the rest of the drawing and I didn't recognize it as that. My day job depends on my ability to read drawings, so the fact that I missed that is kind of embarrassing!!

As to the side frames, I was guessing that having the gunwale plate on the top was taking over the strength requirements that the side frames were once doing, but don't have any where near the knowledge on it that you seem to have so it was good to hear you explain pretty much what I was thinking. It is too bad I just now realized it as they are fully welded in now, but I guess I can cut them out if I decide I don't want them in the interior later on.

Thanks again for the information

Kevin Morin
Posts: 595
Joined: Thu Jan 24, 2008 11:36 am
Location: Kenai, Alaska

Re: Scrambler update

Postby Kevin Morin » Fri Jun 16, 2017 10:53 am

eurof2,
You're welcome to my few cents of opinion. When discussing metal boats, I usually attempt to get in the wider points, IMO, in order to make the discussion as useful to others' explorations as possible- so I get long winded hoping to address as much as I can in a reply?

Do I infer you don't have the bow (pram) plate installed but you have already welded the topsides to the transverse frames? That sequence seems a bit strange - that is why I'm asking.

In general I've made it my building sequence to get the entire hull 'formed'/tacked up/shaped before adding final welds? My question arises from the first post- where you inquire about the location of the bow plate in reference to the frames/keel - and now you've mentioned that the topsides frames are welded in?

We've seen numerous metal boats, here and other sites, where the weld sequence was "Out of Order" that resulted in many hull panel's become misshapen, distorted and wrinkled due to out of sequence welding- so I'm asking about your boat based on my reading of the posts.

Pictures always welcome, and they offer many words of explanation. I'll post some here to show my building sequence as an example.

Image

While not a pram shape, here is a picture of a tiny 14'er I did some years ago- the entire skiff was tacked up- and all the 'shaping' or edge to edge fits of all hull panels were tacked so they were clean and fair- before any weld contraction was added?

Middle left is a flat bar temporarily tacked to the starboard bottom panel- to fair the chine until the chine flat is tacked on. (This building technique does not use internal frames to form the boat- not as common a method of building: framing in internal structure is added after the hull is formed.)

Image

Notice that the shape had to have some 'fairing strips' to keep bulges out of the bottom as it was pulled up - and the bow needed some closure- or tension strips to keep the shape for the chine flat to be added? But at this point everything is just fit and tacked. Welding before all the edges and hull panels were tacked- would have distorted the edges and made a clean shape very hard to achieve - IMExperience.

I've found that welding in sequence was pretty important to end up with a fair, clean and wrinkle free boat? Just curious because of your remarks and questions.

Cheers,
Kevin Morin
Kenai, AK
Kevin Morin

User avatar
gap998
Posts: 355
Joined: Wed May 20, 2015 5:40 pm
Location: Wales, UK

Re: Scrambler update

Postby gap998 » Sat Jun 17, 2017 4:24 pm

I know it's not strictly relevant to this build but those tips may be useful in a stitch & glue design too.
Gary

Planning a whole fleet, but starting with a Zip...I think.

"Just when you think you've made something idiot-proof, someone builds a better idiot!"

Kevin Morin
Posts: 595
Joined: Thu Jan 24, 2008 11:36 am
Location: Kenai, Alaska

Re: Scrambler update

Postby Kevin Morin » Tue Jun 20, 2017 11:53 am

gap, the metal boat assembly method I use is essentially stitch and glue- the outlines of the panels are generated either in the PC or off a plate model- and then scaled up to 'real size' to skip lofting. Edges of all panels are held to edges adjacent and the wire or stitches of the plywood and epoxy method; are tack welds that are left in place- dressed down (shown on another thread on the Forum) and welded over eventually.

The primary difference is the glue. Managing the mix, handling, application and dressing or sanding when done- with epoxies is a cold process with little or no set up state forces. When the glue 'dries' the hull panels are fixed in place by seam tape or strips and cove beads of glue. But when gluing by welding (!) there is contraction to plan. However if the welds are uniform, placed on the hull seams and supports in a planned sequence- the cooling contraction and shape changes can be balanced and offset so the hull panels remain fair.

Perhaps the most difficult item we see in new metal boat builders is the required time to become truly proficient at welding- especially aluminum MIG welding- the back bone of fabricating welded aluminum boats. Adding correctly mixed-by-weight epoxy is not quite as challenging to learn- and it is applied in a less critical to success method and if you add too much glue to the joint it can be removed without distorting the entire hull panel. Not so with welding so many first time welded boat builders find they have not taken adequate practice time they experience 'buck fever' to get building! The "glue" is the primary difference in the metal and ply hull materials using a panel outline approach.

But, I do agree with your remarks that the two methods are similar in construction sequence.

It should be noted that unless you've done a metal boat or two - many first time builders would find this "metal-stitch-and-glue" method kind of intimidating- even though it works well for me. However I've build quite a few welded boats and made countless thousands of mistakes while becoming familiar with this process.

Cheers,
Kevin Morin
Kenai, AK
Kevin Morin

User avatar
Scot2640
Posts: 48
Joined: Sat Jul 16, 2016 7:52 pm
Location: Rochester NY
Contact:

Re: Scrambler update

Postby Scot2640 » Wed Jun 21, 2017 10:34 am

I really admire your welding skill. I wish I learned to weld, seems really cool.
A ship is safe in the harbor, but that's not what ships are for.

http://www.seadreamerproject.com
http://www.youtube.com/c/SixPointsWoodWorks

Kevin Morin
Posts: 595
Joined: Thu Jan 24, 2008 11:36 am
Location: Kenai, Alaska

Re: Scrambler update

Postby Kevin Morin » Wed Jun 21, 2017 11:10 am

Scot, thanks for the kind words, IMO; learning to weld like learning any other skill is mostly practice- like driving, playing piano or drawing- or cutting out metal boat parts! Begins with the interest and practice - well- in the case of welding and metal work there's plenty of reading and research that will help the practice time be most productive.

Thanks again, Cheers,

Kevin Morin
Kenai, AK
Kevin Morin

Kevin Morin
Posts: 595
Joined: Thu Jan 24, 2008 11:36 am
Location: Kenai, Alaska

Re: Scrambler update

Postby Kevin Morin » Wed Jun 21, 2017 11:10 am

Scot, thanks for the kind words, IMO; learning to weld like learning any other skill is mostly practice- like driving, playing piano or drawing- or cutting out metal boat parts! Begins with the interest and practice - well- in the case of welding and metal work there's plenty of reading and research that will help the practice time be most productive.

Thanks again, Cheers,

Kevin Morin
Kenai, AK
Kevin Morin


Return to “Metal”

Who is online

Users browsing this forum: No registered users and 1 guest