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Tkuhlman56
08-18-2016, 10:12 PM
Hello.

My name is Tony, and I have an addiction to sawdust.

Not that I'm complaining, you understand. It's cheaper than some other addictions, and it's legal, too. I've been doing some sort of woodworking forever, it seems. Dad was a carpenter and contractor when I was a kid, and I helped out on some job sites now and then. I've never tried anything like fine furniture - most of my stuff has been utilitarian stuff - shelves, a backyard shed, etc. But I've always wanted to do a cedar strip canoe. I've seen some done by others, and thought, some day I'm going to try that.

Some day arrived last year when I was home from work for Christmas break. I had purchased Gil Gilpatrick's book with 5-6 different plans, and spent a lot of time reading it, studying it, and trying to decide which one to build. Ultimately, I settled on the Puddle Duck - a 14 foot boat. I picked it because I thought it would fit inside my basement shop. The shop is about 20' square, with a steel support post square in the middle. I figured anything much bigger would mean I'd have trouble getting around the ends, or crawling under it.

So this thread will be my build log. I'll post some pictures along the way, along with comments. This is my first time doing this, and the book doesn't spell out a lot of detail about how to do some of the steps, so I had to figure out this stuff on my own. I'm sure there are other ways to accomplish these things, and I'm not surprised if there are better. Feel free to chime in with questions, comments, etc.

DeniseO30
08-18-2016, 10:21 PM
Gil's 14 was my first! Good luck!

Tkuhlman56
08-18-2016, 10:26 PM
OK, prep and setup time.

Gil's book includes full size plans for molds and thwarts and such. I didn't want to cut the plans apart, so I photocopied them onto 8.5 x 11" paper, and taped them together for each mold. Then I cut each mold out of the paper, taped it to 1/2" plywood, and cut it out.

http://i1266.photobucket.com/albums/jj528/tkuhlman56/IMAG1181_zpstlmhn2ob.jpg


The Puddle duck uses 5 stations that sit transverse on the strongback, and 2 identical molds for the bow and stern. The boat is symmetrical at both ends - the molds at stations 1 and 5, and at 2 and 4 are identical. The pieces at the stem and stern are as well, except that they are doubled.

Well, the stations are supposed to be identical. When I cut them out, there were some minor differences in mine. I deliberately cut them just a bit wide of the line, figuring I can trim them down to the exact shape. I clamped matching pairs together, aligned on the base and center lines, and used a Surform plane to work them down to match. Then I flipped one over, realigned and reclamped, and made sure they still matched. A little more trimming, a little shaping, and I was happy.

http://i1266.photobucket.com/albums/jj528/tkuhlman56/IMAG1189_zpsvlfbmems.jpg

Tonight's beer - Dunegras IPA, from Greenbush Brewing, Sawyer, MI. It was a little hoppy and bitter for my taste, but not extraordinarily so.

Tkuhlman56
08-18-2016, 10:28 PM
Thanks, Denise! I'm making good progress. I'll post some pictures I've taken along the way to show what I've done and how it came out. I've decided already I'll probably do another, bigger boat from Gil's book. This one is my practice boat, my learning boat. And I think I've learned quite a bit so far.

Tkuhlman56
08-18-2016, 10:35 PM
Not all my work has been done by just me. I had some help now and then.

http://i1266.photobucket.com/albums/jj528/tkuhlman56/IMAG1179_zpsujafr1le.jpg

When the molds were done, I started on the strongback. I've seen some fairly minimalist ones, but I wanted something a little bigger. And I had some half inch by 1' by 6' pieces of OSB that had once been part of my son's waterbed. So that and some 1 x 6 from Lowes turned into the platform, and some scrap 2 x 4 from here and there turned into legs.

http://i1266.photobucket.com/albums/jj528/tkuhlman56/IMAG1198_zpstqu9kotd.jpg

Tkuhlman56
08-18-2016, 10:46 PM
I went to Lowe's and Menard's over the last few months and sorted through their cedar boards, looking for stuff I could use. Truth be told, I didn't really know what to look for, other than something with as few knots as possible. I ended up with 6-8 boards of varying lengths and widths. Usually they were 1x6's about 8 or 10' long. I got at least one 1x4 somewhere or other, and at least one piece that was 12' long. The idea was that a longer board meant fewer joints in the strips, right? Yeah, but.... I doubt I'd get 12' boards the next time. The strips were long enough to be awkward to handle, and on a 14' boat, that meant they were near the ends - often where the most twist was found in the strip on the boat. Live and learn....

http://i1266.photobucket.com/albums/jj528/tkuhlman56/IMAG1199_zpstrmmkd5e.jpg

The boards got cut into strips about 3/8" thick, and planed down to 1/4" using a Ryobi planer I found on Craigslist. The strongback worked out well as a work surface for this, although it put a ton of sawdust into the air. The workshop is in my basement, so I have to be a little careful about dust. The furnace is in the room next to the shop, and it's pretty good at circulating dust through the entire house.

http://i1266.photobucket.com/albums/jj528/tkuhlman56/IMAG1200_zpskktah2xn.jpg

http://i1266.photobucket.com/albums/jj528/tkuhlman56/IMAG1201_zpswbqgdutu.jpg

My wife doesn't like that so much.

DeniseO30
08-18-2016, 10:53 PM
You are off to a great start! if I may...
http://i1266.photobucket.com/albums/jj528/tkuhlman56/IMAG1199_zpstrmmkd5e.jpg
My shop is in the basement of my 150 yr old house. talk dust! omg.

It's been more then 10 yrs but I self taught myself how to loft from the tables offsets. It's fun once get the feel for it.

we also built from Canoe Craft. the prospector
http://i230.photobucket.com/albums/ee132/DeniseO30/BoatBuilding/IMG_0002_zpsa129ea53.jpg



and the redbird.
http://i230.photobucket.com/albums/ee132/DeniseO30/BoatBuilding/19648763-c92b-40ee-8dbb-c4e99914805c_zps199783cd.jpg
http://i230.photobucket.com/albums/ee132/DeniseO30/BoatBuilding/IMG_0005_zps0fd04118.jpg

Ron Williamson
08-19-2016, 06:29 AM
I went to Lowe's and Menard's over the last few months and sorted through their cedar boards, looking for stuff I could use. Truth be told, I didn't really know what to look for, other than something with as few knots as possible. I ended up with 6-8 boards of varying lengths and widths. Usually they were 1x6's about 8 or 10' long. I got at least one 1x4 somewhere or other, and at least one piece that was 12' long. The idea was that a longer board meant fewer joints in the strips, right? Yeah, but.... I doubt I'd get 12' boards the next time. The strips were long enough to be awkward to handle, and on a 14' boat, that meant they were near the ends - often where the most twist was found in the strip on the boat. Live and learn....

http://i1266.photobucket.com/albums/jj528/tkuhlman56/IMAG1199_zpstrmmkd5e.jpg

The boards got cut into strips about 3/8" thick, and planed down to 1/4" using a Ryobi planer I found on Craigslist. The strongback worked out well as a work surface for this, although it put a ton of sawdust into the air. The workshop is in my basement, so I have to be a little careful about dust. The furnace is in the room next to the shop, and it's pretty good at circulating dust through the entire house.

http://i1266.photobucket.com/albums/jj528/tkuhlman56/IMAG1200_zpskktah2xn.jpg

http://i1266.photobucket.com/albums/jj528/tkuhlman56/IMAG1201_zpswbqgdutu.jpg

My wife doesn't like that so much.

It's probably too late to matter,but summer is a good time to do loud,messy stuff outside.
No worse than the horrible habit of mowing the yard.
R

Tkuhlman56
08-19-2016, 09:07 AM
Denise - I see the walls in the background of the Redbird picture. I see what you mean about a 150 year old house. I do have a way to deal with the dust, at least somewhat. I'll come to that as I catch up on pictures. It's probably not OSHA compliant, but it reduced the level of airborne dust quite a bit. Less dust is better, yes?

And I have to figure out how to get the pictures to show here, instead of just posting a link. I know there's a thread or FAQ about that, and I thought I had it figured out. Time to go dig that out and reread that.

Ron - I did do a lot of the dusty work in the garage earlier in the summer. I have a lot of pictures of the build process, but I'm trying to be selective about what I post, or you'll be bored stiff looking at the same shot taken from about 5 degrees to the left, then from overhead, then....

Thanks for both your comments - it's nice to find a community of like-minded people who have done this. I should have been posting here 6 months ago, but I was either busy at irk, or working on the boat, or slaving away over a noisy lawn mower.

jameshan
08-19-2016, 09:51 AM
Good luck!

Tkuhlman56
08-19-2016, 10:06 AM
Good luck!

Thanks!

BTW - the actual process of gluing on strips will probably be done in a couple of weeks, and then I'll start sanding. Does anyone have recommendations about sanders or the actual process? What works best - palm sanders, or some sort of longboard sander? Do I sand the outside and fiberglass it, then move to the inside? Or sand inside and out, then apply glass? Any input is appreciated.

sailcanoefan
08-19-2016, 10:20 AM
OK, prep and setup time.

Gil's book includes full size plans for molds and thwarts and such. I didn't want to cut the plans apart, so I photocopied them onto 8.5 x 11" paper, and taped them together for each mold. Then I cut each mold out of the paper, taped it to 1/2" plywood, and cut it out.


I read (maybe in Gil's book - or Ted Moore's) it's better to copy with tracing paper directly on the mold, to avoid distortion. Photocopy may be source of errors. I would certainly use tracing paper, then cutout outlines. Next use masking tape to stick the mold on 3/4 inch plywood. Now it's easy to trace with a pencil the contour. Use a band saw to cut the plywood. Take care not to cut inside the line.

DeniseO30
08-19-2016, 10:32 AM
Pull scrapers first, keep em sharp! (more on the inside then out) red devil type. diagonal draw so you don't tear out the soft cedar. My 5" Dewalt still running after 8 boats! The easy part is the exterior of the canoe. Inside the hull is pure hell to work! even the epoxy and glass are hard to master on inside curves, it wants to slide down and epoxy likes to puddle.

A long board is reall good for fairing but you may not really need it on strip builds. still good to have on hand.

Oh. on the Puddle duck? you may want to be mindful of the stem shape to the bottom. Some I've seen were zero rocker and track like kayaks.

Keep on gluing!

White River
08-19-2016, 02:08 PM
Welcome to the world of strip building! I've now built two a prospector ranger that I abuse on the white and muskegon rivers regular all year long and a wee lassie II that is my show off boat that only sees open calm waters with no bottom scrapping:rolleyes:. The ranger was built from 5/4x16' deck board from Menards and the Wee Lassie was built from scarfed 6' and 8' aspen also from Menards. I use a milwaukee ROS that was originally hook and loop but that wore out and i now use the sticky disks with ok results. The glassing will seem dunting at first but if you work evenly and mix thouroughly, work the wet edge carefully you will have no problems. I think canoe craft details this process better than Gil's book. I have both. I lofted all of my molds. Canoe craft was spot on. My Wee Lassie was all messed up on the center three stations(the book had the incorrect dimensions and I didn't catch it until I was 3/4 stripped ugg) and I had to re fair the molds as I stripped following the natural bend of the wood and considerable eyeballing. I do not recommend this method lol. I then took my lofted molds and traced them with carbon paper all tapped down firmly to my particle board. Worked great.

BTW Im in Twin Lake. You?

White River
08-19-2016, 02:11 PM
Whoa. you need to sand and glass the outside FIRST. Then pull off the molds sand and glass the inside. might want to get canoecraft and read the section on glassing. Ted does a very thorough job describing it step by step.

DeniseO30
08-19-2016, 03:19 PM
Whoa. you need to sand and glass the outside FIRST. Then pull off the molds sand and glass the inside. might want to get canoecraft and read the section on glassing. Ted does a very thorough job describing it step by step.
WR, he's building from Gil Patrick's book, but yes complete the outside and pop her off the form!

MoMan
08-19-2016, 03:55 PM
Does anyone have recommendations about sanders or the actual process? What works best - palm sanders, or some sort of longboard sander? Do I sand the outside and fiberglass it, then move to the inside? Or sand inside and out, then apply glass? Any input is appreciated

I built a Prospector with the Canoe Craft book. If memory serves me, after pulling the staples out of the forms, I did initial smoothing with a sharp block plane (very shallow cuts, made 45 degrees diagonally across the grain), followed with a long board. Once satisfied with that, glass and epoxy. Repeat the planing and sanding process, then pop it off the forms and work the inside. The inside is harder because of the convex curve, which really limits the areas you can use a block plane. You can find curved card scrapers but it will be slower than on the exterior.

For pictures, google Thorne + pictures + woodenboat. His instrux can be found in numerous places on the forum.

Good luck and keep posting your progress and questions.

--Mike

Canoez
08-19-2016, 04:22 PM
What MoMan said. Start with the plane across the strips at a 45 angle to fair the hull. Makes quick work of it. For a beginner, go with a longboard and progressive grits of paper to avoid "dishing" the hull with a random orbital sander. Most folks don't realize just how soft a cedar hull is until it is too late.

For the inside, a scraper (Some places you can contour the blade of a Hyde paint scraper and then use a hook-type scraper. I've used a random orbital sander with a soft contour pad after that. Personally, I prefer to use a smaller "longboard" with a foam backer to get the inside. FYI - be patient with the inside- it can be a bit tedious.

Rich Jones
08-19-2016, 04:24 PM
What are you using to glue the strips to each other? Titebond III is excellent. No need to use epoxy as it's too hard to sand. Since everything is fiberglassed, the Titebond III is more then adequate.
Also, put packing tape on the edges of your molds so you don't end up gluing the boat to them.
How are you getting full length strips? Scarfing the shorter pieces together? Would have been better off by going to a regular lumberyard and getting full length stock. Too late now? My current build is strip planked and the strips were over 17' long. A little floppy to handle, but it worked out just fine. Keep on building!

Canoez
08-19-2016, 04:27 PM
What are you using to glue the strips to each other? Titebond III is excellent. No need to use epoxy as it's too hard to sand. Since everything is fiberglassed, the Titebond III is more then adequate.
Also, put packing tape on the edges of your molds so you don't end up gluing the boat to them.
How are you getting full length strips? Scarfing the shorter pieces together? Would have been better off by going to a regular lumberyard and getting full length stock. Too late now? My current build is strip planked and the strips were over 17' long. A little floppy to handle, but it worked out just fine. Keep on building!

Titebond or Titebond II are both good as well - any decent carpenter's glue will do as the strips will be sheathed in epoxy and Fiberglass which protect the core material. If you've got lots of drippy bits a damp rag cleans them up a bit better than the Titebond III.

Jamie Orr
08-19-2016, 04:32 PM
What MoMan said. Start with the plane across the strips at a 45 angle to fair the hull. Makes quick work of it. For a beginner, go with a longboard and progressive grits of paper to avoid "dishing" the hull with a random orbital sander. Most folks don't realize just how soft a cedar hull is until it is too late.

For the inside, a scraper (Some places you can contour the blade of a Hyde paint scraper and then use a hook-type scraper. I've used a random orbital sander with a soft contour pad after that. Personally, I prefer to use a smaller "longboard" with a foam backer to get the inside. FYI - be patient with the inside- it can be a bit tedious.

If you'Re good, you can do the inside with a disc sander using a flexible backer. This from the old David Hazen book. I never got the knack but my building partner wasn't too bad so it worked out okay. That was Hazen's 16 foot Micmac, a lovely hull we'Re still using 30 years later. Back then we used polyester resin, finally went to epoxy on the third skin.

Jamie

Canoez
08-19-2016, 04:38 PM
If you'Re good, you can do the inside with a disc sander using a flexible backer. This from the old David Hazen book. I never got the knack but my building partner wasn't too bad so it worked out okay. That was Hazen's 16 foot Micmac, a lovely hull we'Re still using 30 years later. Back then we used polyester resin, finally went to epoxy on the third skin.

Jamie

Yep. If you're good, you can. Auto-body places have thick low-density foam discs that go between the sanding disk and the sander's platen that do a good job keeping you from digging the hull - the bigger the diameter the better off you are. You need a light touch and you need to stop and check things because you can't see what you're doing while you're doing it. ('zat make sense?)

MoMan
08-19-2016, 04:59 PM
Titebond or Titebond II are both good as well - any decent carpenter's glue will do as the strips will be sheathed in epoxy and Fiberglass which protect the core material. If you've got lots of drippy bits a damp rag cleans them up a bit better than the Titebond III.

A lot of folks also like the WeldWood plastic resin glue. Once I got used to it (and carefully followed the instructions) it worked out really well. It's a powder you mix with water. The appeal to me was that it sanded really well without gumming up the sandpaper, plus it dries to a dark brown, so it blends in nicely with western red cedar. Another plus is a much longer shelf life for the powder.

Canoez
08-19-2016, 06:13 PM
Todd loves the stuff. I agree with the sanding to a point - it does powder up, versus gumming up paper. I've used it but wasn't a fan for this application - just a personal preference.

If you've got big enough glue lines to gum up paper, you've got BIG glue lines.

Todd Bradshaw
08-19-2016, 07:04 PM
The Hazen (Wilderness Boats) method actually used a solid rubber 7" backup plate for sanding the insides, which was (is) called a Black & Decker "Super Flexible". They're actually not all that flexible, in fact they're pretty damned stiff. They were used on a big 3450 RPM disk sander, like a Black & Decker Wildcat using 80 grit resin-backed floor sanding disks. You would remove the side handle from the grinder and cup one hand over the head, next to the disk. The other hand was on the trigger and you were leaning up against the hull because it took considerable pressure to bend the disk enough to get it to match the contours of the hull's inside. This was, by far, the single most dangerous step (both to you and your boat) in the entire building process as it was easily possible to sand all the way through the hull from the inside before you knew what was going on.

Wilderness Boats was cranking out a canoe in about 75 man hours of labor, you won't be, so disk sanding the inside with the big stuff really is one of those "don't try this at home" things.

http://i1303.photobucket.com/albums/ag153/ToddBradshaw/assorted/bdsf1_zps5yquf82m.jpg

http://i1303.photobucket.com/albums/ag153/ToddBradshaw/assorted/bdsf2_zps4jngqbr8.jpg

I eventually found a smaller Craftsman 1/2" drill - 6" disk sander combo that had a somewhat softer rubber pad, which I switched over to on insides for more control. You could still grind through, but it was less likely. Unfortunately they had cheap bearings and I went through several of them during my strip building days.

Initial sanding of the outside wood surface was done with the 80 grit floor sanding disks and the big disk sander, but instead of the Super Flexible, the resin backed disks were backed up by a hard, flat phenolic disk pad. It was much more controlled than sanding insides, but it usually took chopping up a boat or two to get the hang of the sanding process. The foam-padded disks (8" feathering disks) were only used for finish sanding (150-220 grit) and were also used on the big disk grinders, but only on the outsides of the hulls and both on the bare wood and eventually the resin filler coats after glassing. Once we switched from polyester resin to epoxy resin I had to change to a Milwaukee 1725 RPM polisher for sanding the resin, as the big old B&D ran so fast that the heat from friction would smear epoxy.

Since most builders these days are building for their own use, there are less extreme means of doing most of these things, and the fact that they take longer isn't a big deal. I'd still use my big disk on the outside wood sanding, but the rest would likely be scrapers or a small random orbit sander.

Canoez
08-19-2016, 07:42 PM
Jerry Stelmok had something like that he used. Was a slow-speed 12" orbital polisher adapted for sanding on the cedar and canvas canoes. He used it for tapering at the stems, getting out planking lumps and bumps, and tapering the outwales. If you had large contact area it wasn't too scary. If you were working a corner, material would just vanish before your eyes.

Jamie Orr
08-19-2016, 08:23 PM
A lot of folks also like the WeldWood plastic resin glue. Once I got used to it (and carefully followed the instructions) it worked out really well. It's a powder you mix with water. The appeal to me was that it sanded really well without gumming up the sandpaper, plus it dries to a dark brown, so it blends in nicely with western red cedar. Another plus is a much longer shelf life for the powder.
I recall another Hazen recommendation was for aliphatic white glue. It looked and behaved just like regular white glue except it sanded without trouble. I found some in a hobby shop but when that ran out we couldn't get more, so used white glue and put up with gummy sanding - scrapers and planes helped.

Really conjuring the memories today, I might have to go for a paddle tomorrow!

Cheers

Tkuhlman56
08-21-2016, 10:00 PM
Wow... lots and LOTS of advice - thanks, all!!!

In some order of the sequence that the comments came in:

Sailcanoefan - re: photocopying - I taped the sections together, cut them out on the lines, and laid them on the originals. They were spot on, so it was easy to trace those onto the plywood for the molds. When cutting them out and trimming them, I could then trim until the line was just gone. It seemed to work. I used 1/2" plywood for the molds. 3/4 might have worked better.

Denise030 - I'll look for the pull scrapers - thanks, Denise. I had planned to do the sanding/shaping on the outside of the boat while it's still on the molds, and then remove it. That just seemed the easiest way to do it. The molds and strongback keep it at a comfortable work height. The only issue might be doing the 'glassing inside, and having the smell in the house. I may have to move the whole operation to the garage for this part. There's a big window in the background of some pictures that was spec'd to be big enough to get a sheet of plywood through. This part of the house is an addition we had put on 10 years ago. Yeah, the boat's been in the back of my mind that long...

White River - I used 1 by 4's and 1 by 6's, mostly from Menards, and in 8, 10, and 12 foot lengths. Most have been scarfed in 8:1 joints as I glue them in place. I've been happier with the 8 and 10 foot lengths. My workspace is a bit small, and waving a 12' piece around in there is likely to knock into something. I'm closing in the last 8-10 pieces in the bottom, so these last pieces will be full length. The rest have 1 joint somewhere in the run from bow to stern. A couple have 2 joints, where I started from each end, and realized I had a gap in the middle - oops.

BTW, I'm in Grand Ledge, just west of Lansing. Mapquest sez you're not far from here, relatively. Ever get over to the Quiet Water Symposium at MSU?

And I'll look for Canoe Craft - thanks for the tip.

MoMan - re the block plane - I'll look into it. I've had problems working with a plane before, but it might have been a cheap plane, or poor technique.

Canoez - I will look at the longboard as well. I'm getting near the point where I'll need it, so I'll have to look soon.

Rich Jones - I'm using Titebond III - and I did tape the edges, thanks. That's working well. I'm scarfing the joints, and it's working well for me. We'll see how it looks when I get it sanded and 'glassed. This is my practice build. I'd like to do something in the 16, maybe 17' length at some point.

Jamie Orr and Todd Bradshaw - a disk sander for the inside scares me a bit. We'll see how I feel when I get to that point, though. I may use some leftover scrap strips to build a section of the hull to practice doing the inside.

more in a bit - my laptop wants to do a restart now....

Jamie Orr
08-21-2016, 10:27 PM
Wow... lots and LOTS of advice - thanks, all!!!

In some order of the sequence that the comments came in:

Jamie Orr and Todd Bradshaw - a disk sander for the inside scares me a bit. We'll see how I feel when I get to that point, though. I may use some leftover scrap strips to build a section of the hull to practice doing the inside.

more in a bit - my laptop wants to do a restart now....

Hi, I probably shouldn't have even raised the matter - as I mentioned, I couldn't control the disc sander but my partner could. So maybe only if you've used one before, and even then do some test sanding.

Jamie

upchurchmr
08-21-2016, 10:49 PM
Just another 2cents.

The only thing I find works well for the inside is the ROS with a soft pad. Mine is Porter Cable with a 5" disk. There are curves where I wish I could get a 3" disk.

Like any other power sanding, you have to sand (keeping the sander moving), feel to see what you just did, compensate to match the actual contour. Oh, and remove excess glue before sanding - I like a hand scrapper for the glue removal, if you can not remove the glue when you are stripping.

I've got a fantastic idea for a conformable hand sanding pad, adjustable to get different radius's across the pad and adjustable curvature along the length.
The only problem is it doesn't work. I'm almost about to decide I need to make about 10 different shaped sanding pads and forget the adjustable part. :o
If I could get the paper attachment mechanism off of a "Preppin Weapon" I'd make the multiple geometries.
http://www.pilotshop.com/cache/200-200-/catalog/graphics/12-00505.jpg

Canoez
08-22-2016, 09:01 AM
Just another 2cents.

The only thing I find works well for the inside is the ROS with a soft pad. Mine is Porter Cable with a 5" disk. There are curves where I wish I could get a 3" disk.

Like any other power sanding, you have to sand (keeping the sander moving), feel to see what you just did, compensate to match the actual contour. Oh, and remove excess glue before sanding - I like a hand scrapper for the glue removal, if you can not remove the glue when you are stripping.

I've got a fantastic idea for a conformable hand sanding pad, adjustable to get different radius's across the pad and adjustable curvature along the length.
The only problem is it doesn't work. I'm almost about to decide I need to make about 10 different shaped sanding pads and forget the adjustable part. :o
If I could get the paper attachment mechanism off of a "Preppin Weapon" I'd make the multiple geometries.
http://www.pilotshop.com/cache/200-200-/catalog/graphics/12-00505.jpg

We'd contour blocks of 2x4 to match the inside of the hull, use some 3M spray adhesive to bond a piece of foam to the contour and then using a piece of either a belt sander's belt or a roll paper, we'd wrap from top under the foam, to the top again and staple the paper to the wood block. Keep it simple.

upchurchmr
08-22-2016, 09:09 AM
When I'm trying to smooth out the inside of a kayak, I'm trying to get it smooth by forcing the contour into a shape instead of just smoothing out what is there.
I also make sanding blocks out of foam with glued on sandpaper and it works well for final sanding.

However, foam on a contour block with spray glued on paper is a throw away. I don't want to make them over and over.

DeniseO30
08-22-2016, 09:32 AM
Here again, on the inside, the scraper really comes into its own. We filed the blade into a slight curve and knocked sharp corners off so it would not dig into the soft cedar. Long diagonal strokes will make curls With moderate pressure, if you need brute strength it is not sharp!

Many people don't like scrapers because they never used one that was properly sharpened! pull scrapers can be sharpened about the same as card scrapers http://www.highlandwoodworking.com/how-to-use-sharpen-wood-scraper.aspx

I think the native Americans used flint, clam shells, obsidian to do the same work. but I wasn't there. :rolleyes:

upchurchmr
08-22-2016, 11:57 AM
There is a real difference in doing a canoe and a kayak.
The canoe has much more open curves.
I also own at least a dozen different scrapers. One that works well is an old floor scraper (with a handle), with the blade ground into a curve.

WoodyHuscarl
08-22-2016, 02:36 PM
Has anyone tried using a detail sander with interchangeable heads, or a Fein MultiMaster? Seems to me they might be good for tighter spots, but it would take days to do the whole interior.

Also, if you leave the molds in while sanding, you are going to leave a stripe of unsanded area where each mold is. If you want a good angle to access the interior, your can rest the hull on padded sawhorses, and block it at whatever angle is best for you to reach in with your tools.