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Messages - Brian.Dixon

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1
In the overhead view I was attempting to show the shape of the transom as it leans aft.  It looks like sheet 000d.  I just didnít add anymore detail like you did.  I built the transom per plans with four more inches added to the sole.
  I think I will cut everything off and leave the stringers wild for now.  I can always cut them off if I change my mind later
  I had not planned on any bracket or jack plate is there really any advantage?   I donít even begin to know what the prices are or where to find one.

Ah!  I get the view ... thanks :)

4" to the sole .... keep in mind that in the original design, the lower motor mount bolts are right between the bottom of the drywell and the deck.  If you raise the deck, which is a great idea, just make sure you account for where those lower bolts come through so you can either leave the deck open to the bilge or have access through a large deck plate to those bolts.  And it's a good idea to use an aluminum plate as a big washer for those bolts too.  They'll stay trouble free the longest that way (you should check their torque now and then for the first few trips.

My preference is for a short jack plate.  It'll let you tune the cav plate-to-water height just right.  I like that better than 'move that heavy motor up or down a set of holes' (which usually leads to calling it "good enough" and NOT adjusting it).


Brian


2
Todd,

Nice sketch!  Looks like it'll work, but I have one question.  In the top view of the transom, you've got angular sections rather than a flat transom?  If not building a laminated curved transom, then you'll want those nice heavy motor boards (2 LVLs, one above the other) running clear across the boat from one side to the other.  Now, if that's what you are doing and those angular sections are only higher than the motor boards, then that's fine.  Just use strong transom-to-side and transom-to-bottom seams with milled glass fiber, wood powder, silica epoxy mix and strong glass.

Plus, I suspect you'll have a short motor bracket or jack plate between the two swim platforms?  Make sure the manufacturer's clearance requirements are met for when the motor is turned hard to the side.  I expect there's enough room between the extended stringers, but you'll want to verify that.  If you don't know what motor you'll use yet, just check several manufacturers and outboard sizes and design for worst case.

Brian


3
Thanks Dan, for sharing!

Now go get that thing wet and post pix of blood on the deck!  :D  All those fish are swimming right past you unmolested and that ain't right!

Brian


4

That curved transom sure is a beaut! 

Brian


5
Nice progress Todd! Almost time to get some sides slapped on that thing. :)

Brian, from your answer to (2) here, as I am also kicking around scarfing some extra length on the bottom panels to max out my stringers, what types of performance or stability issues manifest when the bottom back portion isnít perfectly flat or true? I have seen mention that it should be in numerous places, but havenít heard an explanation of what the adverse effects are if itís not. I imagine it probably depends on the type of defect (cup, curve, etc) but would love to learn more to make a more informed decision.

Ideally, you want water to slide straight backward off the bottom of the boat, disconnecting cleanly at the transom.  This will produce the best efficiency and performance.

As far as what defects do what:

- If the bottom is a hump near the stern, it'll tend to suck the stern deeper into the water (bow higher), and part of your horsepower is going into maintaining that downward suction on the stern of the boat.  Same thing, but much lesser, occurs if the radius of the edge where the transom meets the bottom is too large.  If the issue is too large (hump), you can also introduce porpoising to the boat (same thing as a boat with a CG too far aft due to loading etc).

- If the bottom has a hollow towards the stern, it acts more like trim tabs, pushing the bow down and making it plow a little more than it should ... again, a waste of energy from your motors, lower fuel efficiency.

- If you have both humps and hollows, or one side has a hump and the other a hollow, then you've got situations fighting each other and see more of a general loss of efficiency (which also means speed, BTW).  If one side has a hollow and the other side a hump, then the boat will heel to the side that has the hump when on plane.

You achieve optimal planing trim and fuel efficiency if none of the issues above exist.  That's the goal.  It's easiest to extend bottom length when all plywood is flat on the shop floor.

Something else to consider is that this boat tapers narrower from amidships to the stern, so extending the boat would continue that tapering and it'll appear that the transom is too wide as a result.  The RIGHT thing to do, assuming putting the original transom design at the stern end of the boat (not the swim platform shown above), is to allow the transom to define the width of the stern even if it means moving shelves outward to do so.  This will produce more of a gap between side panels and the chine flats, but it's perfectly fine to fill them and glass the seams right over the filled gap.  It'll be small... a quarter inch or so.

Note that if the hull lengthening or 'extension' is a swim platform behind the transom, that it's OK to allow the small amount of taper to continue, but I still prefer the swim platform being as wide as the original transom, even if it introduces a gap along the edges of forward or 'original' transom... It's all fine tuning though, small gaps, and will work either way.  I just like more flotation in the stern than less...

Does that thoroughly confuse things?  :D


Brian


6
Thanks Jason.  I feel like itís almost about to look like a boat.  It sure is nice to have so much more room in the shop.

  Brian, I have no intention to use a bracket.  It sounds like the sponson idea is not the best choice for my build after all.  I didnít realize until further study that the motor was back as far as the sponsons.  My build will be much different than  the boat we are talking about. 
   I think after you pointed out so many differences Iím going to trim off the the bottom past the transom and mock up the swim platform for you to look At.

Lots of thinking goes into a boat, and it'll be great when it's done!  And yes, definitely post sketches and we'll get it all tuned in before you invest time and cut wood!

Brian

7

The white GA in Oregon with sponsons was a little heavy in the stern.  Partly because of no flotation in the center section and the fact that the motor was on a bracket as long as the sponsons (or close to it).  Would've been better to build one as shown above so no loss of flotation if a long bracket were desired.  It's a big heavy motor too, which didn't help.  And he built a lightweight house and walk-through cuddy.  All in all, that boat performed great regardless, but picks up a little porpoising at speeds above 44.

1) Stringers and glassing ... not so much a strength necessity near the stern, but you want them wrapped with glass and encapsulated with epoxy considering their 'in the bottom of the boat' location.  Waterproof and check proof (crack-proof).

2) Yeah ... unless you like scarfing in an area where you want the bottom to be as flat as possible (followed by fairing and crossed fingers), I'd let the bottom panels define the swim platform length.

3) Yes, just glass over the butt-joint top and bottom with at least 10-oz and 6" overlap on each side of the seam, and do everything you can to make them run flat like a true continuance of the chines.

4) Probably ... Might want to consider trailer bouncing it around.  The further from the axles of the trailer, the more kicking in the kicker ... if you can remove it for towing, that'd be best.  Use a strong bracket or make a mini-transom for it.

Brian

8
Hey ya ol' fart ... it's about time that we heard from you again!  Yeah ... I'm not the expert to recommend photo hosting sights.  Photos suck up a lot of disk space and bandwidth, so I'm not surprised that they charge money.  If I were you, I'd start an FB sight as you mentioned and just upload a couple of pix at a time ... tag Glacier Boats of Alaska in all of them!  Ok, but it's free anyway.... let SUCKERberg pay for it....

Brian


9
Iím referring to a ďswim platformĒ support not a bracket.  Iím building the transom per plan.  The outboard will hang off it. I want a swim platform of some kind if for no other reason than to get back into the boat when I fall out.  I thought maybe someone had used the stringers that were sticking out to facilitate this.  Maybe I will draw a picture.

Oh ... Gotcha.  I think everything will work fine as you describe :)  But yeah, show us a sketch and I can say for sure, but I misunderstood at first and think your swim platform concept is fine.

Brian


10

Yes, these boats are comparatively light weight compared to commercial glass or aluminum boats.  It is better to extend the bottom as shown above than it is to have a bracket that's raised above the bottom of the boat, e.g. Armstrong style brackets.

Brian

11
General Discussion about the Great Alaskan / Re: Fishy fish
« on: May 24, 2019, 08:55:54 PM »

The Fishy Fish forums are back UP!  Sounds like there was blood and pain involved, but Steve's got the site back up and running!

Brian

12
General Discussion about the Great Alaskan / Re: Farebody strake
« on: May 24, 2019, 01:44:45 PM »
If it's like the Tolman, once you get down to about a third of the way back from the bow where the bottom begins to flatten out  it's flat enough to not have to fuss with it.

Nailed it.  :) .  For the readers not at this step, note that you plane or sand the 3/4" wide flat on the bow (down to just behind the 'knee' where the fairbody turns upward into the stem) BEFORE you apply glass tape to the exterior fairbody seam.  If you are not going to beach the boat and don't need strakes, and you prefer a sharper bow, then you only need to sand the fairbody/bow enough for the glass tape to follow the shape nicely when applied.

See page 106 in Part 1 of the 2-part construction manual set.

Brian


13
General Discussion about the Great Alaskan / Re: Fishy fish
« on: May 24, 2019, 07:38:25 AM »
Anybody know whatís up over at fishy fish forum?

Fishy fish is down for the count from what I can see.  I spoke to Steve Dampier, the owner/operator of those forums and apparently the server farm got hit by some kind of malware.  Steve could've switched to a new company and restored a back-up from his back-ups if he had any ... I'm wondering what his back-up strategy is?  Or maybe his company is leading him on and he'll restore a back-up when the company gets back on track?  Hard to say, but the site's down for the count for the foreseeable future.  We're all in a waiting game on that one....

FYI: My hosting companies assure me that they back up daily and can recover from anything.  In addition, I back up the glacierboats.com database every 2 weeks and the website (automatic via idrive.com) daily.  The whole forums site (database, settings, all files etc) every 2 weeks.  Technically, that's in addition to the hosting company's back ups ... hopefully if anything happens, we won't have to go through Steve's pain and we'd likely be back up within 2 days or so, worst case .... he's really unhappy right now. :( :(

Brian


14
Where do I find that document?  I only purchased the study plans, which came with what looks like an abbreviated version of construction plans.

I just emailed you part 1 of the construction manual - let me know if you don't receive it.  AND, you make a good point - I need to add to the study plans so that the different models are illustrated in there somewhere.

Brian


15
General Discussion about the Great Alaskan / Re: Micro balloons
« on: May 24, 2019, 07:26:33 AM »
Adding silica always seems to make any mixture smoother and spread easier than just the other filler alone.  I use silica along with everything - wood flour, micro balloons, plastic fibers, etc.  The only time I don't use it is when I'm wetting out fiberglass.

Well stated ... I like silica added to most everything too.  I don't use it straight, except when making a syrupy mixture for laminating ply-on-ply or similar because it flows better than other filler mixes.  I'll use it 100% if I run out of other stuff, but it cures hard as stone, so don't use it by itself if you want to do any scraping or sanding later!

Brian


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