Conchfish AL 17.6T build

[gandrfab]

I didn't eyeball your drill press.
Mine is an older model with a belt drive, when I have to drill heavy steel I'll set it on it's slowest speed (still too fast)
Heat is your enemy. I had a long run (320ish) 3/4" holes I needed to drill in 1/4" Stainless steel in lieu of an oily mess I kept a bowl of water right next to the drill press, brought the bowl up and lifted it to the bit to cool it. 

I'll pre drill, sometimes step drill, 2 drill bits before final size.

When drilling with larger bits or if I'm sharpening any bit for steel, I'll lessen the relief angle

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 Hand sharpening bits, another talent that takes practice. Is pretty helpful in small shops that don't afford a bit sharpener nor endless supply of new bits. 
 

[kmorin]

G&R, Carl, I've found the best luck drilling w/ a mag foot drill using the rotabroach bits and I use the Hougen brand drill motor to drive them - but other brands will hold these bits and work well.

I generally drill mating flanges to the bolt size or over 1/32" maybe? Depends on what bits/broaches are available?  I have drilled the vertical legs of the Davis Jigs 1/8" larger.  On those holes the bolts will have to fit from the sides while lifting and lowering w/ an overhead winch/chain fall so I don't see any need for them to be tight. I think I used 5/8" broach for a 1/2" bolt?

For flanges, I find the 1/2" r'broach and 1/2" bolt to be snug as a result, where the flanges meet face to face, I used the same size bolt and bit.

I haven't looked into Magfoot drill motors for quite a while, the Hougen has been fine and long lasting- I just don't use it much anymore, think it's at a friend's shop to enjoy more frequent time out of the box?  Understand the other brands have followed Hougen's lead and now offer good drills but can't claim any familiarity.

I found a video by Izzy Swan, not long ago, introducing me to the Viking Norseman Vortex Point drill bits for steel. IMO they perform much better than the older 'conventional' split tip style in steel on my drill press. I use them on aluminum and steel and they're great for speed and clean cuts.

I have very gradually gotten away from the conventional drill bits with the split side geometry in favor of these other types. I found an adapter for the rotabroach bits for the standard drill press chuck so the broaches can be used in a bench setting as well.  I have a couple of the smaller broach dia.s kits as well, for thin material, that cut much nicer holes than either hole saws or conventional twist drill bits.

Cheers,
Kevin Morin
Kenai, AK
 

[m32825]

Work has been getting in the way of boat time lately, but I've got some time off coming my way next week. Shoulder PT is complete. Temperatures in the shop have dropped a degree or two, welding season is on the way!

I'm not the only one who senses a change of season. We have black bears in our area. Had to run this guy off a couple times recently for raiding our bird feeder. Doesn't look like he needs to pack on many pounds to survive the brutal Central Florida winter...

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I've been easing back into the build. Working on getting the longitudinals in place. I thought I had pretty good spatial skills but I'm finding out that I'm not as proficient as imagined. One thing I'm learning is that I need to think a step ahead when fitting things up. For example, when placing the center hull panel against a longitudinal, also consider how the outer panel is going to land on the opposite edge of the longitudinal. I had some places near the bow where the inner hull panel landed nicely but the longitudinal wasn't at the proper angle to allow the outer panel to follow the curve of the transverse frame. It was holding the panel above the frame.

I'm doing CAD (Cardboard Aided Design) to see how things come together at the bow. Looks pretty good, how do you like my tacks? The table made it super easy to use the hull panels as templates for cutting.

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You guys are a wealth of information. I never considered sharpening a drill bit. My drill press is a bench top Craftsman model, for wood and light metal work. As it reminds me every time, it's not made for big holes in metal. I'm not doing this for a living, so I'm trying one of the cheaper Chinesium mag drills, should be plenty capable for my needs.

    -- Carl
 
 
 
 
 

[m32825]

New tool Tuesday, clean 40mm hole in 1/4"

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[kmorin]

Carl,
Now THAT's what I'm talking about! Did you ever drill (mill) such a smoothly cut hole, that size, before? Probably not. 

Cheers,
Kevin Morin
Kenai, AK

[gandrfab]

yes please

https://www.amazon.com/gp/customer-revi ... B0C27S768K

[m32825]

You're right, that hole was laughably easy to create. In fact, I'm probably going to go through a phase where my steel projects have more holes than they need, just because it's easy.

Last place I worked I had use of a Bridgeport knee mill, but only used twist drills for hole making. I was missing it for punching holes in steel, but not anymore. Another bonus is that a mag drill takes up a lot less shop space than a Bridgeport!

[m32825]

Game called on account of hurricane Helene this week. On generator overnight, lots of small debris to clean up, but we came out fine. Spent a couple hours chainsawing and tractoring for neighbors Friday.

-- Carl

[kmorin]

Carl,
Glad to hear you came through the storm OK.  We don't really see weather like that here so I'm always checking the maps to see how those I know in the areas affected faired in the blow; apprehensive of their safety.  Glad to hear you're OK.

Welded boats keep well. I cut and tacked up a skiff once, then got busy and buried in the shop with other boat orders. It was a couple years before I finally welded that tacked-up hull, and it had sit outside and been rained on, dust and pollen covered on it too.  Cleaned up and welded out fine.

Cheers,
Kevin Morin
Kenai, AK

[kmorin]

Carl, G&R, Capt'n Dave, other Floridian members.... well everyone South of the Dixon and Mason line....
I hope y'all'er are safe from (or evacuating in front of) the next big storm coming through your neck of the woods?

Just watched a couple of drone footage videos of the Florida coast after Helene and now understand there's Milton coming to mess up whatever was left in tact by Helene!  Wow those folks up in the hills of Carolina sure took it on the chin!

Sheesh, I'm willing to stick with a bit of seasonal cold to avoid those kinds of storms.

Good luck and God Speed, Hope everyone's safe in this next blow.

Cheers,
Kevin Morin
Kenai, AK

[m32825]

Hi Kevin,

Thanks for thinking of us. Two storms this size in the space of two weeks is definitely unusual. I'm about done with prep. Central Florida has it easy compared with folks where the storm comes ashore!

-- Carl

[gandrfab]

Hoping for the best outcome for all. 

Pick up, put away anything that can become a projectile or that you want to keep from blowing away.
Keeping on top of trimming dead tree limbs is helpful. 
Hope you don't take the brunt of the storm.
Then clean up. 

The news reports on the worst, sensationalism sells more commercials.
It is best to prepare for the worst, because it could be you. But for most, with a good attitude it's not all that bad.  

2004 was a rough year Hurricanes Charley, Frances and Jeanne took out our power for about 7 weeks total.

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[m32825]

Hi guys,

We came out okay. No trees down, but some good sized limbs and lots of smaller stuff. Burned a couple tanks of chainsaw fuel turning big things into smaller things. Power has been out about 18 hours, there's a tree on the lines and lines on the ground, no estimate on time to repair. We switched to generator a little ahead of the outage and have a few days of diesel fuel on hand.

-- Carl

[kmorin]

Carl,
that's good news, I hope others are as fortunate?  Thanks for keeping us updated.

Cheers,
Kevin Morin
Kenai, AK

[gandrfab]

As far as our hurricane Milton experience has been so far.
Our household made out very well. I have nothing to complain about.
Power's still out at home, shop had power restored last night.
Whole bunch of debris at home to pile and burn, and one large limb that fell into the oak tree it was growing on and wedged in place with the lowest point about 9' from the ground riding parallel to the trunk and 8" to 10" thick. We will be calling the professionals to remove.

[m32825]

Power is back, just shy of three days on generator. Lots of debris to clean up. We've had cooler weather since the storm passed, this might be my new favorite hurricane!
 

[gandrfab]

We had our 1st morning under 70° for this season and it was 63° on my front porch.

[m32825]

We had our 1st morning under 70° for this season and it was 63° on my front porch.

 

Wednesday forecast is low of 55 and high of 70. Welding season is here at last!

[m32825]

Lots of clean up the last few weeks. Got our place mostly squared away, helped neighbors. Everything is stacked along the edge of the road, county will pick it up eventually. Just so you know I've got my priorities right, when the hurricane went through all my vehicles were parked out in the open, but my boat project stayed nice and dry in the shop!

Got my longitudinals extended and tacked in place. Looking at where my panel edges will actually land and how much to trim.

-- Carl

[m32825]

Panel alignment near the back looks pretty good. I might need to adjust supports on the rearmost transverse frame. It's a challenge getting the aluminum at the front anywhere near the longitudinals to check the fit. I used the hull panels to trace cardboard templates and they fit well, but I would feel a lot more confident if I could see the actual hull panel instead. Is there a way to bend curvature into the the panels to make it easier to fit the front part?

-- Carl

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[kmorin]

Carl, yes, there are ways to bend the panels in both the longitudinal direction and in the transverse direction but I don't see the need to do that?

If I were doing this project at this stage, I'd make sure the keel is straight- 'naturally'; not bent, kinked or hogged.  Then I'd put the inner most sheet on one side or the other and tack tiny small tacks with the VKB's lower edge showing- so each of the two side sheets inner most edges were on the outside edges of the keel.  I'd do this work on one side, then the other. After one side, dress the sides of all tacks that overhang in opposite sides' flat vertical face. Stagger the tacks for the 2nd side.

At the bow and for about 4'-5' aft you'll need tacks close together - 3-4" maybe even down to 2" spaced about 14-18" from the bow where the main turn from bow stem to keel line happens (tightest curve of the forefoot). More curve, tighter tacks, less curve, spread tacks farther long.

Once both inner plates are tacked to the keel, I'd move out to the long and tack there... following the same pattern, but if the plate edge overhangs the long's inner most edge- that will need to be trimmed. Tack it up and then mark in place to get the trim line. Remove all tacks, and clean all edges- fair the line you've marked on the outside of the inner more hull panel's edge so (when cut) it will leave the long revealed.  Note that the line to be marked in on the KEEL side of the long.  Cut, clean, & Re-install them both.

I'd bevel the upper-outer-bottom side of the panels at the keel, AND the long seam. The reason is as I've mentioned arc wander if the joint is not wider at the outside compared to parallel sided.

Then I'd add the outer hull panel but here I'd work from the outside IN. I'd tack this one to the inside of the 'chine' shape and see where it fits over the edge of the long. If not on the outside of the long? Then I'd mark it and cut, fair, bevel and re-install. This allows all the slack or seam allowance to come from the seam between the two panels.

Rant On
I will note again, and feel free to pass to the designer, and plate CNC guy... this hull has way to many panels for such a tiny 'no-speed' boat.  I can't see the bottom being more than one or two pc.s - FOUR??? Sheesh. What does this gain? Countless hours of work for Zero hull performance changes. I'd have drawn her w one pc bottom chine to chine, and she'd perform as well.
Rant OFF

by working the two main seams in priority and cutting out the 'extra' mtl from the long seam in the bottom you're working to keep the two main lines intact while compromising at the line between bottom panels where you can afford to remove material.

Hope this helps?

Cheers,
Kevin Morin
Kenai, AK
 
 

[m32825]

Kevin,

I like how you break it down. I had this picture in my head that I needed to figure out the trimming and complete that before the panels went on the hull. The approach you outline reduces the degrees of freedom and opportunities for miscalculation.

On hull complexity, to be fair to Nathan (plan guy), he did offer the option of a simpler hull. But I knew this had been built once already and I was asking for modifications to add the tunnel, so it seemed like it would be safer to limit the changes. As you've probably found, sometimes your client asks for things a certain way despite your efforts to shepherd them in a better direction. This one is on me. Nathan has since produced updated designs for a couple guys doing production, and those incorporate a simpler hull as you suggest to streamline construction.

I've tacked up a pair of those three-panel assemblies to practice on. I think they came out close enough to give me some relevant experience before tackling the real thing.

    -- Carl

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[kmorin]

Carl,
depending on your sense of adventure; ie. risk tolerance..  you can trim the two bottom panels' internal seam in-place, in one step; if you feel you can control marking system and eventually the saw?

By tacking to the keel and then to the outer chine of the two plates' edges... you could attain an overlap of the two pc on that internal bottom plate seam.  You can, w/ some careful marking, cut that seam in place with a single saw kerf along the top of both panels as they overlap and that would be running the saw blade on the 'top' or vertically above the edge of the long supporting that seam. 

The result will be a trimmed inner sheet and trimmed outer sheet seam directly over the long's (lower or bottom) edge as it is exposed below both inner edges of the resulting but.

This is not a trivial exercise, but... does work if you cut and tack as you go along.  However, lining up the mark to cut is the first challenge to accuracy, saw handling the second.  When the inner sheet is tacked to the keel, it will 'lay' to the long's (now upward facing) surface- 3/16" wide?  If this is covered or overlapped more than 1/16" - then trimming the inner panel is necessary.  Then, if you tack on the outer bottom panel the inner cut line is obscured- so again this is not a trivial method/solution to that seam's preparation.

However, by using an offset marker jig... you can mark the OUTSIDE surface of the hull long; on the top most surface for an accurate saw track/guide.  I will work on a sketch of this marking jig, if you're inclined to give this method a try?  The reason to consider this method is that you don't have to remove the panels from their original 'fit-tacks' in order to get them to fit fair over the long's back up edge, and with a some additional 'side dressing' you can have that seam ready to weld with less repetitive steps and no tack clean-up or rework.

I'm not casting aspersions on your skills in saying you may or may not choose this work method.  I'm just observing that the seam will be lower quality than you'd like if the saw cut is not done with full control of the tool to a exactly laid down cut line in this more critical 'on frame' method of fitting the bottom plates' inter-panel seam.

Cheers,
Kevin Morin
Kenai, AK
 

[m32825]

Kevin,

Haha. Rest assured, my skills will not be insulted in the least by any aspersions cast their way. Actually, I find that day to day life yields plenty of evidence arguing for humility. Builds character, as they say.

I think I'm picturing what you describe. Let's go with that approach.

I welded up one of the three-panel practice pieces. Not my best (I'm apparently a little rusty) but looks like it would work. I started from the narrow end of the open corner, then moved to the back side of the vertical, then gouged a bit and did the front side of the vertical.

The first weld pulled the vertical outward at the front. I'm going to try the back of that portion first on the other one. I'm also going to weld that one with my off hand.

    -- Carl

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[m32825]

Here's the other practice piece. First time off hand, so a little rough. I got carried away with heat on the back side of the vertical, but backing saved me.

Doing the back side of the vertical first controlled the "leaning" quite a bit, but I ended up with sideways curvature. I think my bead size and heat input contributed to that outcome.
​​​​

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