I'll admit it:
I'm a little apprehensive (OK! Scared!) :o of working with epoxy resins, since I have no experience with them.
As a result, I've been dragging my feet and doing all kinds of interim mini-projects, so that this project wouldn't COMPLETELY, stall out. :P
Like lofting/printing out the skegs.
Same trick as before: 8)
Scan the outline off the prints and make a .jpg file.
Insert the .jpg file into a drawing program.
Keep scaling the image larger and larger, until the lofting dimension offsets match the ruler scale on the drawing program.
Save the file (immediately!).
Reposition the huge image to the printable area of the printer on the drawing program and print out a portion of the image, a page at a time.
Align the pages by lining up lofting lines from one page, to the other page.
Scotch tape it all together.
20240619_104523 1024X768.jpg
Use spray adhesive to stick the taped-together pages onto some stiffer construction paper.
20240619_105445 1024X768.jpg
See? EASY!! ;D
Here's what they look like on the bottom of a hull (not mine, since I'm nowhere near this stage of progress).
skegs_1.jpg
Another project that's been making me nervous, is the centerboard pivot bushings inside the hull. :-\
This step is fraught with myriad ways to screw up.
Royally.
Get the holes slanted horizontally and the centerboard can bind up in the centerboard trunk and jam.
Get the holes slanted vertically and you have the same problem, PLUS it rattles inside the trunk on any given tack.
In the SCAMP Camps, they make the trunk and trunk doublers early on and drill all four holes in a stack on a drill press, to make sure everything is 90º
My hull came with the trunk already installed, but the holes were missing.
No actually, it looks like someone tried to put in the holes and got it wrong, realized their mistake and filled the erroneous hole with epoxy.
Pencil intersection is the actual measurement.
20240531_153623 1024X768.jpg
The other issues are mounting the centerboard pin and dealing with leaks.
There are all manner of approaches to installing a a ½-inch S-S pin into ½-inch i.d. bronze bushings glued in the CB trunk.
CB_Pin_1.jpg
They occasionally leak, as the O-ring on the pin below, shows.
Scamp_CB_Pin.jpg
One attempt uses the same bronze hardware as the water ballast drain plug.
CB_Pin_2.jpg
I looked at several of these methods and they all seemed to me, to be too unnecessarily complicated.
I decided to simply use a bronze NPT pipe coupler with a ½-inch i.d. and some bronze pipe caps and a rubber washer in the cap to deal with leaks and hold the pin.
20240624_114200 1024X768.jpg
But first, I needed a way to epoxy it into the trunk where it wouldn't unscrew itself, the first time I tried to remove the caps.
I used a Dremel tool with a cut-off wheel, to cut slots in the threads
The black line is where the pipe cap goes.
20240624_114229 1024X768.jpg
All those jagged cuts along the threads ought to hold the epoxy glue nicely.
20240624_114149 1024X768.jpg
Pipe caps screwed down. They will have a rubber washer inside for water-tightness.
Might even use Teflon pipe tape, haven't decided yet. :-\
20240624_114523 1024X768.jpg
Next, I needed a hole big enough for the bushings, plus room for epoxy glue, to ensure a solid joint.
Used a 1" hole saw.
20240624_115700 1024X768.jpg
But, how to get an accurate right angle hole, using a hand-held drill, on a trunk that is already installed? ???
I haven't had all that much luck drilling, by means of "eye-ball" engineering. :-[
So, after some thought, I made a 90º block that was square in two planes and used it as a guide to hold the hole saw square against the trunk sides.
20240624_115710 1024X768.jpg
Here is the bushing and cap temporarily inserted for fit.
20240624_121022 1024X768.jpg
But, how square is it? ???
I used the tube from my splicing kit, since it was very close to the hole diameter
This is another one of those camera fore-shortening effects; it really is more square than it appears.
20240624_122027 1024X768.jpg
See?!? :D
20240624_122753 1024X768.jpg
Since the outboard hole was not quite 2 mm out of square, I decided to oval the holes with a rasp on both sides a little, to allow me to align the bushings when it comes time to glue them in.
20240624_124120 1024X768.jpg
I will wrap this ½-inch pipe with packing tape (so the epoxy doesn't stick) and use it to hold the bushings in-line and square and plumb, on the trunk.
I can use some stiff wire wrapped around one side of the pipe and run over the top of the trunk and run down and wrapped on the other side of the pipe for vertical alignment, and duct tape and a combination square, for horizontal alignment until the glue sets up.
20240624_125526 1024X768.jpg
Next, I elected to work on making portholes for the dead lights. I had all sorts of scraps to use, from cutting in hatches.
Dusted off the scroll saw and had at it.
20240628_115847 1024X768.jpg
Then I bolted them all together and sanded the edges, uniform and smooth.
Cut out the center holes (not shown here) next.
20240628_150248 1024X768.jpg
They'll need a round-over from a router, but that's a project for another day.
Like, the day after I clean up and organize the garage good enough, that I can even GET to my table router! >:(
Finally decided I had done all the make-work projects I could, to delay opening up the epoxy jugs and therefore: Today's the Day. :o
Started with the centerboard halves.
20240630_115729 1024X768.jpg
Ok, not so scary after all; kind of like a cross between polyester fiber-glassing and varnishing.
I could do this. 8)
20240630_115737 1024X768.jpg
Even have the same issues as varnishing! >:(
20240630_135530 1024X768.jpg
Guess if the epoxy is good enough to hold down a bug that big, then 22lb of lead are probably OK, too.
20240630_135528 1024X768.jpg
While waiting to see if the epoxy would actually set up, I made some screw "washers" for holding pieces of wood to the hull where clamps won't reach, while the epoxy sets.
They are wrapped with packing tape to keep from inadvertently becoming part of the boat, since the packing tape won't stick to the epoxy.
20240630_145743 1024X768.jpg
The screw length was chosen to go through the 9mm wooden pieces and into the 9mm hull, but not completely through it.
20240630_152937 1024X768.jpg
One of the problems encountered by the early SCAMP builders, was the cockpit seats sagging a little, when trying to rely solely on the seat/hull fillets. Now they recommend cleats along the hull to reinforce the seats.
Since the hull is curved, the 9mm plywood seat-edge strips need a little "convincing" to conform to the shape of the hull.
Now that I've gotten my feet wet, (or at least, my fingers sticky!) I think I'm going to be making a lot more progress on the SCAMP build. :)
Charles Brennan
I knew it was something! Working with epoxy is relatively easy as you have found out. There are some pitfalls which mostly involve curing time in the summer. (Too quick!) And clamping pressure (too much). Great work so far. Mmmm...be sure those bushings are actual bronze, which looks a whole lot like brass and is two totally different animals. Which is available if you know where to go (Fergusons plumbing supply and expensive). Keep plugging away and soon enough you'll be sailing! I kept having trouble daydreaming and staring at curves once the hull was done. That daydreaming is actually a form of bonding though ;D
I share your concern about working with epoxy. I built a stitch and glue epoxy composite skiff. If I had it to do all over again I would build a ply on frame skiff with more actual woodworking and less epoxy work. I did four months worth of work over two years. I learned that in the heat of the summer forget it. I learned that in the cold of the winter forget it. I will only build again if the ratio of skilled work such as woodworking, metal working, plumbing and electrical is much greater than epoxy work. Just an opinion.......
Charles, what CAD program are you using? More importantly, what format are the drawings in? If they're .dwg, .dxf, .dws, .dwf, .dws, or .dwt, I could help with that sizing. It's easy in the CAD program I use to size something so that it is exactly the size you want.
Let me know if I can help.
I've gotten to the stage in life where I know my limitations. It's too hot, it's too cold, it's a nice day, let's go sailing! So projects stall. So I have taken the advice from another sailing friend. Throw cash particles at the problem. (Let someone who knows what they're doing do it) :D
Chica, Went right down the rabbit hole, I did! ???
Rasterized or pixellated images don't maintain finite element vectors, so it's tough for a scanned image to have that info for a CAD program.
Which is why I used a drawing program and played games with the scaling.
After reading your suggestion:
Firstly, I tried to see if there were some way I could get my scanner to save scanned image files as .dxf or .dwg files.
No luck, there. (Not that I really expected it.)
Perusing on-line, I discovered an application called Inkscape (which I've had on my desktop for years, using it for something else) WILL convert a .jpg file into a .dxf file.
Whoa!! :o
Promptly loaded my rudder .jpg into Inkscape and saved it as a .DXF file.
It whirred and churned and eventually spit out Rudder.DXF.
Kewl. 8)
So THEN, I opened up LibreCAD and opened rudder.DXF.
Nada.
Explored on-line some and discovered everybody else has problems using .DXF files in LibreCAD.
(My CAD program of choice these days, on account of it's FREE!) ;D
Hmmm . . . . .
Updating the app didn't help and converting from .DXF back into .JPG in Inkscape worked fine, so it's not Inkscape, or a corrupted .DXF with screwed-up poly-lines, or something.
Started with AutoCad in 1987, using Release 9, on DOS.
Used to have a copy of AutoCad 14 from way back when, so I loaded that.
Won't work on Windows 11.
Hmmm . . . . .
Started up VirtualBox and loaded up a copy of Windows XP and installed AutoCad 14.
Got it running . . . . . eventually.
Been a minute, huh, Charles? ??? Geeze!! I used to KNOW this stuff! :-[
Copied over the Rudder.DXF file . . . . . .
a n n n d d d d . . . . . AutoCad 14 doesn't recognize the current .DXF revision.
>:( ARGGGGHHHHHH!!! >:(
Anyway, now I'm intrigued about the possibilities of getting honest-to-goodness .DXF files from a .JPG
There's an on-line conversion website called Convertio, that purportedly converts .JPG or .PDF files to .DXF or .DWG. So I'm going to play with that next, to see if maybe their .DXF files or .DWG files will load in to LibreCAD.
Thanks for killing my WHOLE DAY, Chica!! >:(
Just Kidding!! ;D
The best thing about this board is not just the advice and stories, but how one suggestion can spark another (even though different) idea.
Thanks, Noemi,
Charles Brennan
Wayne, Channeling a little Dirty Harry, here: "A man's got to know his limitations" . . . .
Which has always been a problem for me.
I always figured I was as good as the next guy, so I rarely considered that I might even HAVE limitations, when I wanted to do something.
As a result, I've done a great many things. (Not all of them, well; racing in the CDCR comes to mind.) :-[
I also believe you should try everything at least once and the Fun Stuff, TWICE!! ;D
The other issue is, having cash particles to throw at the problem.
Believe me, I'd LOVE to just order a pre-fab SCAMP from Gig Harbor Boatworks and go sailing, but it's just not in the budget.
Nor am I inclined to swallow the anchor, just yet.
So I toil away, and with any luck at all, I'll have another boat to sail and maybe even, before I'm too old to sail it!! :o
Charles Brennan
Riley, I made SURE McMaster-Carr was selling me bronze hardware, instead of brass.
Most everything I do is in salt water, so I can't fool around with easily corrodable metals.
I do concede it's not Silicon Bronze, but it was the best bronze I could get my hands on and NOT brass.
I have this recurring nightmare: (especially on hot nights)
I awaken from some nautical accident.
The boat is fairly trashed and the storm that trashed it must have knocked me unconscious for a while.
I have jury-rigged a mast from the boom, and am flying a jib rigged as a loose-footed main.
Just when I figure I have a fighting chance to make it, all my hardware starts failing on me.
Ever seen a heaping spoonful of sugar dropped into a cup of hot tea?
Turns grey and then dissolves?
That's what all the cleats and turnbuckles and shackles are doing, in my nightmare.
Every time I fix one thing, or fashion some mickey-mouse workaround, something ELSE crumbles into flecks of metal and washes over the side. It's like I can't keep anything together long enough for something to work.
BIG Fan of Noble Metals, my Man.
Charles Brennan
Well, currently I'm out of epoxy, so I hope nothing on the boat breaks! I was SO scared of epoxy, I didn't use it! I glued everything with resorcinol and overlaid the glass with polyester reisin. I really like the resorcinol because the working time is much greater and it is less toxic. But epoxy is quicker and actually easier to work with. I did have one problem with the mast once when it cracked during extremely cold weather. The base wood cracked, not the glue line. I cut the crack out and installed a replacement half section and it has been fine ever since. Luckily that crack was in the section below the deck when stepped, so it isn't even visible and was a relatively easy fix. Had it been in anywhere else I probably would have rebuilt the whole mast. Relax CB. You have modern chemistry to protect you when you are miles from safety in shark infested waters :o
I should elaborate a bit on my distaste for working epoxy. As mentioned I built a Stitch and glue skiff. Because stitch and glue construction is kinda like unibody construction in the car world, the primary strength comes from the box construction and the integrity of the seams. Consequently all the seams are reinforced with multiple overlapping layers of tape prior to the glass fabric being laid on and wet in. As a result there is a great deal of fairing that has to be done to blend the seams. It is that part I hate the most. Sand, fair, sand, fair, sand fair, guide coat, sand, fair.............
Although I've never built a ply on frame, I get the impression it is much less of that not so good thing.
Fairing....oh man. That's where 3/4 of the work building a boat comes in! Getting it to fit and look GOOD. Your eye can see the tiniest of mistakes and it takes lots of work to get it right. I only managed to do that about 75% of the time too. The rest was figuring out how to make it acceptable and remedying my inadequacies.
S R Cat was faired with polyester and a filling compound mixed in, to make the filets around the frames and elsewhere. I seem to remember thinning it all with a dollop of acetone but I don't ever want to do that whole process again. And all those fillets were overlaid with tape while wet, so in effect, it becomes a composite intersection of wood and opposing forces to make a joint.
And yes, I was stumbling around in the dark in my ignorance. I've often wished I could rebuild the boat once more, because I'd do so many things differently, including using epoxy. Despite ALL THAT, she has given reliable and safe passage for a quarter of a century. With today's resources, it is easier and very safe structurally, as well as producing a product much different than a vanilla production hull. Back then I was stumbling around on the internet trying to find out how to do some particular something. That's actually how I stumbled on this place, and wound up getting in touch with CJ. Nothing was precut and I started with a pile of plywood and lumber and somehow came out with a boat in the end.
Man, time sure flies doesn't it?
SO...fare well CB. Or is it fair??? It'll be good. Nothing is ever perfect, believe me. There is a range from unacceptable to the best, and the best can make you THINK it is perfect, but trust me. It isn't. I've built so many things in my life and have never managed yet to accomplish that. I've even seen one of those machinists make a part on a lathe with those microscopic tolerances and say to myself, I'd have done that specific action differently. Live and learn. You never stop and you constantly learn, but just because you would do it differently later doesn't necessarily make the original grossly inferior. (Well, except in MY case ) ;D
Man, you're really going after it!
Just a note. Seems like a lot of trouble scaling your skeg drawings. That would scare me. Why not rough out your skeg, scribe the hulls curve and presto!
IMG_6851.jpg
IMG_6852.jpg
IMG_6856.jpg
Charles, I do believe I can import .pdf files into my CAD program. Also .jpgs, but you can't do much else with those. I have imported a pdf, drawn OVER it in CAD, then scaled the drawn part. Had to decide what part of the line to draw over - inside, outside, center? But it worked out.
What a great thread.
If only all of the non specific boat work tips given over the last 20 years could be put into a How-To book
The Captain of this ship could abandon us and with the book profits sail off to Tahiti. Or Put-in-Bay.
Noemi, I tried out that file format conversion web site (Convertio) and input Rudder.JPG and the only CAD output option was .DXF (which had failed in Inkscape) and then loaded it into LibreCAD:
Screenshot 2024-07-03 092755.jpg
SUCCESS!!! ;D
I have recently discovered I am missing the transom cap piece from the collection of plywood pieces I bought last December, so this newly discovered process will be getting a workout in the coming months.
While I am grateful for your generous offer of help, I am even more grateful that you pointed me towards an idea for a solution that I can do for myself.
"No Man Is An Island" but I've always considered myself a peninsula! ;D
Just too independent, I guess.
Thanks, Chica,
Charles Brennan
I don't convert; I import. But glad you found something that works!
Quote from: Riley Smith on Jul 02, 2024, 09:07 AMFairing....oh man. That's where 3/4 of the work building a boat comes in! Getting it to fit and look GOOD. Your eye can see the tiniest of mistakes and it takes lots of work to get it right. I only managed to do that about 75% of the time too. The rest was figuring out how to make it acceptable and remedying my inadequacies.
I enjoy epoxy work, but Riley's comment on Fairing is so true! Fair - sand - fair - sand.......... The hard part for me is when to say it's "good enough now".
Quote from: Noemi - Ensenada 20 on Jul 03, 2024, 12:28 PMI don't convert; I import. But glad you found something that works!
Noemi, Zoom in a little and you'll notice that there are actual polylines; nothing to trace over.
Think conversion is the way to go.
Very cool.
Charles Brennan
Riley and DBthal: So I should fair to a fare-thee-well?
Always been more of a "form follows function" kind of guy.
While I want a decent and presentable boat, I'm maybe more accepting of a "work-boat" finish, as opposed to a "wooden boat show queen" type of finish.
Hey! *I'M* all lumpy and bumpy, why should my boat be any better? ???
That's my inclination, anyway. ::)
But a Southern Upbringing is a hard thing to overcome.
Even writing this I can hear in my head, the voice of my Great-Grandmother (long-dead, these 50+ years) saying:
"Do it Right, or do it Not".
Or my Grandfather: "The Best you can do, is barely Good Enough."
Having spent a life-time trying to over-come that drilled-in indoctrination and striving for:
"Better is the Enemy of Good Enough."
I honestly can't say how it's going to turn out.
If it doesn't sink or leak water and maybe even sails, I might count that as Good Enough.
One guy's opinion,
Charles Brennan
Hi, CB I haven't been able to get on the form for several months. I posted today for your help getting back here on your part 1 Scamp post at SmallCraftAdviser Scamp forum. Which inspired me to try here again today and finally was able to figure out how to do it. I sure did miss all the scallywags here!
I had hoped to make the Cedar Key small boat gathering but was unable to contact you because of the 403 error message which prevented me from logging in here. As it turned out I was in FL to visit my 100-year-old Dad in Rehab after he recovered from Covid during the boat gathering and couldn't make it anyway.
I look forward to following your progress on the Scamp. Epoxy is easy. In hot weather I mix small portions as that reduces the amount of heat generated by the chemical bonding when you mix it. You could always work with the epoxy at night or early mornings when things are a bit cooler.
I am currently beginning on making a canvas tent for my Scamp. I don't know much about using a sewing machine but have all the materials now on hand. So I am going to bite the bullet and learn to sew. I have twice fully wetted down the canvas duck and let it dry out in the sun hoping to reduce any shrinkage to a minimum. It really is too hot to work after about 11 here.
Here is a link to the video of the tent I hope to make. The tent section of the video starts at 26:49 on the video
https://www.youtube.com/watch?v=oJKFX1SmXEI
Charles. how think is that centerboard?
Riley, The centerboard is made from two pieces of 18mm plywood. Adding two layers of glass and the requisite epoxy, the overall thickness at the thickest part (it is foil shaped, so the edges are thinner) is about 38mm - 39mm or around an inch and half.
In the pic below, the left side is the top of the centerboard and it looks (to American eyes) like two ¾-inch pieces of plywood.
20240701_131300 1024X768.jpg
Hope this clarifies,
Charles Brennan
Dale, I tend to think about posts some, before I answer them; your skeg scribing idea has a lot of merit.
Skeg_Dale.jpg
I used something similar: a compass and pencil.
Screenshot 2024-07-06 173646.png
This was useful for getting my bench seat tops to conform to the curved hull sides.
20240609_143804 1024X768.jpg
My concern with making a skeg template was not for matching the bottom of the hull shape:
20240619_105445 1024X768.jpg
It was getting those curves on the opposite side of the skeg.
I do NOT draw well. My first attempt at lofting lines for the rudder was disastrous.
To get those graceful lines on the skeg bottom required far more precision than I'm capable of achieving.
Fortunately, I'm able to get computers to draw with that kind of precision, FOR me!! ;D
And now, thanks to Noemi (resident TSBB goddess) I can now get those scanned images into a real CAD program, instead of just a drawing program. Instead of constant re-positioning of the image in the printable area of the drawing program, I can now print from a CAD program using extents and co-ordinates.
What I (greatly!) lack in drawing skills, I compensate for in computer skills! 8)
However your idea will work great for me when it comes time to start fitting the skeg to the hull.
Keep the ideas coming!! :)
Thanks,
Charles Brennan
It looks like you're doing a nice job, Charles!
If it's not too late, I'd like to suggest that when you add those panels to narrow the cuddy opening (B-4) you make the opening a few inches narrower at the top.
The reason for that will become apparent if you look at photos of Howard's capsize tests. When capsized, a SCAMP floats at a bit more than 90 degrees to horizontal, so narrowing the opening at the top will help keep water from pouring into the cuddy.
Cheers,
Rob
Rob, Thanks for the suggestion. I hope you weren't basing that idea off a pic I posted that had significant camera distortion. It looked like the panels were angling outwards, but that was just the camera. In reality, I leveled the boat both fore/aft and athwart ships, then used a level to strike a line that was plumb with the front of the bench seats.
BH#4 vertical 1024X768.jpg
Looks like it's angled, but really, it's plumb.
From what I've seen of the pics of other SCAMP build blogs (including capsize pics) putting in "wings" to narrow BH4, that seems to work good enough.
SCAMP_capsize.jpeg
Apparently I didn't pick your brain enough, two years ago at a Cedar Key Small Boat Meet, :) so if you have more ideas or opinions, I'm more than open to them!
Thanks,
Charles Brennan
Charles, You've got me thinking about SCAMPs more than I have in years!
The first one that comes to mind, of course, is that iconic bow-on photo of SCAMP #1 reefed down in a breeze, looking for all the world like a sailing bulldog. That's the shot that got first got my attention.
Then I saw the photo of Mike Monies's RED SCAMP sailing along just after having been holed by a tree stump. You can't tell there's anything wrong with her! That got me thinking about the compartmented hull, and having the bottom well armored against rocks.
The first SCAMP I saw in person was #6, B. FRANK, which Steve Haines brought to Mystic Seaport for the WoodenBoat Festival. I didn't get to sail it, but I did look it over and climb around on it. I was disappointed that the cockpit wasn't deeper, but otherwise liked the design enough to order a kit from Josh Colvin, who was also there that day.
The first SCAMP I actually got to sail was Marty Worline's Fat Bottom Girl, which he brought to Cedar Key after his division win in the Everglades Challenge. I finally got to see how a SCAMP would perform on the water! I liked it but I still missed having a deeper cockpit.
As I started building Puffin I became concerned that the hatches in Bulkhead 3 were too small to crawl through, so I made my own sort-of oval hatches that were *just* big enough if I needed to get forward for some reason.
It was about then that I saw Howard Rice's thread about his expedition version, Southern Cross, SCAMP #2, and his design for a footwell, which answered my concerns about cockpit depth. After a few mockups I basically copied his plan and have been totally happy with it.
I've seen several other homebuilt SCAMPs since then with other folks' mods and brainstorms built into them. Some of them are brilliant and a few of them make me cringe!
I prefer sailing Puffin solo, and I like to sit as far forward as possible, right against the cuddy, so I made a tiller extension (not a hinged hiking stick) so it falls to hand when I'm there. It also allows me to sail standing up with the tiller braced against the small of my back. I love sailing standing up, because I can see down into the water ahead and venture into places where no sensible sailboat should go!
Instead of that crossbar with the swiveling cam-cleat for the sheet, I mounted a homemade thumb cleat against the aft face of Bulkhead 5, down in the footwell. I hook the sheet under it and can then hold it down with one foot on the ballast tank, leaving both hands free. As a kid I was taught never to cleat the sheet in a dinghy...
I'll leave it there. I trust you have perused the SCAMP section of the SCA website, which is chock full of brainstorming by other SCAMPers, many of whom have lots more sea miles under their belts than I have!
As a kid I was taught never to cleat the sheet in a dinghy...
Good teaching!