Non-Bear Mountain Designs

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Jim Dodd
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Re: Non-Bear Mountain Designs

Post by Jim Dodd » Tue Dec 20, 2016 7:58 pm

One other observation, that you can't see now, is when you remove the forms, and flip the hull over.
Unless you radiused the edges on your forms before hand. There will be dents, where the strips contact the forms, some places worse than others. Mostly in the bilge area.

Go to about any Hobby store, and get a glue bottle with a long slender tip. Big time saver !

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I'd come up with a better method of holding you strips in place.
Many use bungees, or bicycle inner tubes, and spring clamps at the shearline.
Do a search for North West Canoe. Dennis Davidson has a lot of shop cam videos. No Sound, but on one of his latest videos, he uses bicycle inner tubes. Check it out.

If you are using 3/16" strips, and with the dents in your strips, you won't have much wood left, by the time you are done sanding.

Again I'm just trying to help ! Good luck !

Jim
Keep your paddle wet and your seat dry!

Rehd Brown
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Re: Non-Bear Mountain Designs

Post by Rehd Brown » Tue Dec 20, 2016 8:21 pm

Not a problem Jim.

I wasn't sure the Paulownia would hold up under the bungie cord style and I'm sure that inner tubes would crush the strips. Both are stretched out and would be constantly pulling on the wood, possibly compressing it over time. That's why I chose the clamps. Once you put them in place, they hold at a constant pressure, whatever you tightened them to. AS you can see, this stuff is softer than even I realized.. it crushes pretty easily.
I think the problem is using the wrong bits for B&C, and with even 5/8" strips it's hard to get them to turn to the radius of the bilge. 1/2" wide strips in that area would have been a better choice. If you look back at some of my earlier pics ( I think ) I showed the forms and it's a very tight radius in that area. The Prospector has much softer radius'. I would not be having near the problems on that boat. I've used these clamps in this manner on other builds with a friend and had no issue with then crushing the wood or pulling the strips down to the forms. (cedar and redwood) I plan on building another and will use 5/8" strips for the first 4 or 5" then switch to 1/2" at the bilge.

I appreciate the suggestions. That's how we learn new techniques.

Thanks


Rehd

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Re: Non-Bear Mountain Designs

Post by Cruiser » Tue Dec 20, 2016 8:39 pm

I adopted this method from Randy during my first stapleless build. I use cam buckle straps, so you can regulate the pressure very easily, plus the straps are wide enough to not leave any marks.

Once the glued strip is in place, I lay a 1/4" dowel on the top cove and then wrap 3/16" shock cord around the bottom strip and back up and over, applying a nice even clamping pressure. Again, you can easily regulate how much clamping force, by how much you stretch the shock cord.

Then when the shock cord is on, I tighten the cambuckle strap to snug the whole thing against the mold. It has worked really well for me. Maybe you will get an idea or find a way to apply something like this.

Image

Brian

Rehd Brown
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Re: Non-Bear Mountain Designs

Post by Rehd Brown » Tue Dec 20, 2016 10:39 pm

I appologize for my ignorance, but, what is a Cam-Buckle strap.
I guess I'm not explaining myself well.. my gapping problem is coming from the fact that my joints are too flat and in order to pull the next strip down to the form, it's opening a gap where the strips contact. The inner cove edge is, for lack of a better term, leveraging the bead up out of the cove itself. It doesn't appear that any amount of clamping is going to do both, make contact with the mold and keep the bead in contact with the bottom of the cove. If the clamps didn't dig into the strips I'd keep using them, but, the joints just aren't going to pull together. They are together on the inside, but leave a slight gap on the outside.
Let me put it this way... the minimum radius I can get with the 1/4" B & C on my 3/16" thick strips is still greater than the radius of the turn of the bilge on my forms. In order to make it, I should have used 1/2" wide strips or find 3/16" B & C bits that will make a more proper joint. Or Both..!! :sad

A different method of clamping at this point would mostly just prevent the divots(sp?) in my strips, which is not a bad thing. I'm pretty much through the sharp curved portion now, so things should go together a little better. I'm not going to sweat it on this boat now, since the intended recipient is no longer interested. I'll let the kids play in it soon as there's some water back in our lakes and rivers. If it doesn't look too bad, I'll put it up over my fireplace... With my tiny livingroom, that will take up almost one whole wall. :laughing

If/when I make another one I'm going 1 strip higher on the sheer, I may soften those curves a tad, I'll use one or more of the suggested methods of clamping and try to find a different set of Bits, if that's possible.

Time to put this away and go watch "The Wood Whisperer" and check out his tablesaw sled and his Torsion Box style work table. I'm doing some changes in my garage to make more room, and more efficient use of what I end up with. Hey, when you're retired, ya have to keep busy... right..?


Rehd

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Re: Non-Bear Mountain Designs

Post by Cruiser » Wed Dec 21, 2016 10:56 am

Hi Rehd,

Cambuckle is just the type of strap lock, usually these are ratchet, which is the common system and Cambuckles, which are just a locking plate you pull the strap through and it grabs. The harder you pull, the higher the tension ... for this work I use cams because the ratchets can put too much pressure on the work. If you are doing ranch work, I suspect you have ratchet straps all over the place ( I have a set in my truck to secure loads), the cambuckle straps are the ones you tension by pulling the strap by hand.

There shouldn't be an issue using 1/8" radius bits on 3/16" strips, the B&C will obviously be shallower, but they should still align once put together, even in a transition (turn) ... if yours are opening on one side, I think I would double check that the B&C is properly centered on the strips. If either is not dead center, that can cause an issue. I read an article suggesting that using bits one size up is actually preferable to using the exact size, so the strip design should work well.

The strips need 2 clamping regimes to apply 1) to hold the strips together and 2) to hold the strips to the molds. With stapled, the staples provide both at the molds, and usually strip to strip clamping is augmented between the molds.

With stapleless, it gets a little more complicated, in that the clamping systems (at least most of what I have reviewed) are pretty much separate. So in my post the strip to strip is accomplished with shockcord and 1/4" dowels (to protect the cove) and then the clamped strips are pulled to the molds tightly by the straps. How you strap can be flexible, with ratchet, cambuckles, large nylon ties .... it just is just to pull those clamped strips into the right shape.

Brian

Rehd Brown
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Re: Non-Bear Mountain Designs

Post by Rehd Brown » Wed Dec 21, 2016 1:49 pm

Ah yes... We use a few ratchet straps, but, of the 10K lbs load variety. We mostly use highway chains and binders, but, we use the straps for hauling hay on our pick-ups and trailers. I was picturing those on my canoe where the weight of the ratchet alone would probably crush a few strips. :) The only thing I've used out there with a Cam-Buckle, if I'm reading that correctly, would be on my furniture dolly. It's not actually a cam, but, it does bind and gets tighter the more you pull the strap through two knurled steel rods, where one is fixed and one floats. Where does one get things like that in a size small enough to use on these boats.? And what's a good source for this shockcord. I am unfamiliar with that.

I'm assuming you meant 1/4" radius on 3/16" strips, and yes, I'd always heard that was a good size combination. I would not be surprised if it was my alignment on the strips as that wooden router table has seen better days, none of which were intended for this type of fine work, and I had some kind of difficulty just getting them reasonably aligned. I've since gone out and purchased a new cast aluminum router table and transfered my router to that. That will be one problem solved before my next build.
Actually, I'm going to have to make a few more strips to finish this boat, so I'll try it then.

I tried holding the strips together with the blue painters tape and it didn't seem to stick to the Paulownia strips too well. It was always slowly peeling and letting go. However, it stuck to the birch dowels very well.

I'll see about locating some Cambuckle straps and shockcord... and then 'hopefully' get a close up view of just how it's being used if anyone has a couple of good close up pics. I'm sure I can figure it out, but, it's always nice to see how it's been used successfully and save the brain power.

Definitely some changes coming for the next build, and that will start immediately following this boat.
It's been raining weekly here and if we can get over 12" - 14" I believe we'll have water standing deep enough to actually put a boat in the water around here. Unfortunately we're just now getting enough snow for the skiers and that's way behind past years. Looks like it's going to be another dry one this year. We shall See..!! So, with all the oil pipe lines they are trying to put in, why can't we put in some water pipe lines so we can take some of the flood waters back east and in the south and channel it out here where it can be put to good use..?? Hmmmmmmm... another topic for another forum..!

Thanks Brian


Rehd

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Re: Non-Bear Mountain Designs

Post by Cruiser » Wed Dec 21, 2016 2:40 pm

I am not in the states, but almost any hardware store (i.e. Home depot, Lowes) should have both, if I was going to purchase new cord material, I would likely substitute surgical tubing (if you can find a cheap supplier) for the shock cord, 3/16" is a good size, the advantage of the tubing is that the glue falls right off.

Home Depot:
Cord: http://www.homedepot.com/p/T-W-Evans-Co ... /205327133
Straps : http://www.homedepot.com/p/8-ft-x-1-1-4 ... /202224203

For straps, I like the strap ones, you can just loop them around under the mold and back to the buckle and not have to worry about the hooks ( I do prefer metal buckles though, these are just an example).

Brian

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Re: Non-Bear Mountain Designs

Post by Cruiser » Wed Dec 21, 2016 2:58 pm

This the best closeup I have of how the straps and cord are used. Two things I needed to add that aren't obvious, there is a guide for the strap near the top of the pic, and if you look at the bottom left strap, you can just see a plywood piece just under the first strip. The guide is to keep the strap in place over the mold and the piece at the first strip is just clamped/fastened to the mold to prevent the strap from damaging that strip when you apply tension.

Image

If you go to page 6 of this directory and scroll down to the Kipawa 16'6" build (Cruiser), there are a few more pics and how this used.

Brian

Rehd Brown
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Re: Non-Bear Mountain Designs

Post by Rehd Brown » Wed Dec 21, 2016 3:25 pm

Thanks Brian

The straps I've seen at H.D. and Lowes. The shockcord I haven't seen, but, I'm sure they have it. Possibly at sporting goods stores as well, but expensive. I believe surgical tubing can be found at hobby stores since they use it for fuel line on models, and possibly some medical supply outlets. I will check it all out and pick up what I need. If I can't find the tubing around, I'll do a search for it online.

I assume that the shock cord is a continuous wrap with the ends attached to forms or the bench and that I'll need the cambuckle straps for each form.

In the center of your pic above you have a darker strip (thin) going across the center... in the middle, just below it, there's a gap or dark area about ? 6" ? long... that's what it looks like on several strips where I'm making the transition around the bilge. It's definitely a small gap, and couldn't close it, so I'm just going to deal with it. Normally I would demand better of my work, but, this is a first on this particular design and I didn't think it through on those bends.

Thanks for the info Brian... I'll check out those pics later, but now, it's time to get some last minute shopping done and get back to put another strip on each side of the S.G.

More later....


Rehd

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Re: Non-Bear Mountain Designs

Post by Cruiser » Wed Dec 21, 2016 5:10 pm

The only gap I can see, is actually where I damaged the cove edge, it isn't a gap and I didn't see the damage until it was too late to grab a different strip.

Some of the strips are wider, they were from the previous build and my QC wasn't what it is now, consequently you can also see some strips are proud, that is because they are slightly thicker than the surrounding ones.

They were done with a skilsaw, which works great, but there will always be differences between batches simply because the width setting isn't very precise. Although I still use this method to make strips, I also plane them to final thickness to save work (at the shaping phase) and I feel I get a better fitting strip. That may be subjective on my part, the strips are certainly usable with out the extra step, but I have the planer, so it isn't a lot of extra work.


Brian

Rehd Brown
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Re: Non-Bear Mountain Designs

Post by Rehd Brown » Thu Dec 22, 2016 12:38 pm

Weirdest thing guys... I posted a picture of putting straps on my hull, and one of how some of the strips broke loose, and when I got on just now this morning, that post is not there..? I don't see it on any other categories where I may have goofed.. Think I'm going back to bed and wake up again and see if it comes back... :thinking

Rehd

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Jim Dodd
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Re: Non-Bear Mountain Designs

Post by Jim Dodd » Thu Dec 22, 2016 7:17 pm

Thanks for the links ! I've been looking for Bungee cord, and was just at HD, Before your post ! I guess I have another good reason to go back !
Thank Brian !

Jim
Keep your paddle wet and your seat dry!

Rehd Brown
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Re: Non-Bear Mountain Designs

Post by Rehd Brown » Thu Dec 22, 2016 8:40 pm

Hey Guys
Well, I went out and found 4 ratchet straps from my motor cycle tools and used those on the worst offenders and they pulled them down very well. Well enough that I ran over to Harbor Freight and got some cam straps to finish up. They worked great.! The glue wasn’t dry when I got back 30 minutes later so no problem.


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One problem though… I had some strip joints pop loose and left a gap that won’t close up. They are not bad and I’d rather have to fill those than have the boat out of shape.
That was yesterdays stuff that I thought I posted, but, guess it’s floating around in the O-zone somewhere.


Image

Got two more strips on today and the clamps pulled everything down. However, when I take them off, the side are springing out about ½”. So, it’s time to pull out the Hot Glue Gun and stick them down where they are now. The only hard bends now are between last molds and stems. Close to 75* - 80* twist. May have to put strips on dry and hang clamps off the side of them to get the twist started. I can leave it for a couple hours and maybe it will relieve some or most of the stress and make them fall into place.

Image

I didn’t get a picture of it, but, I checked the strips on the inside next to the molds and sure-nuff, they are squished down a bit. I haven’t tried the damp cloth/hot iron yet, to see if those divots will come out. However I did start wiping off the excess glue from the last couple of strips.

Still haven't had a chance to hunt down surgical tubing. It's insane out there trying to shop for anything right now.

Thanks for the tips Brian & Jim


Rehd

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Jim Dodd
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Re: Non-Bear Mountain Designs

Post by Jim Dodd » Thu Dec 22, 2016 9:29 pm

Good luck with the divots. a little moister and a hot iron might work. I've never tried it.
Some of the gaps you are seeing in the bilge area, will sand away. You will be surprised.

The twist required to keep the strips to the forms, can seem to be a lot. One trick I've seen on YouTube, and read about, that a heat gun, the kind they remove paint with, was used carefully to prebend strips.
If you have such a heat gun, try it on a scrap strip, and see if it will work on Paulona. Again this is one I haven't tried. If it burns, or darkens the wood. You be the judge !

The hull is coming along !

Once you get the stem forms covered, it gets easier !
One trick I just learned by doing recently. That's if you do the Canoe craft method of closing the hull, and I highly recommend it !
Is to stop a few strips before you get to the center ! When you finish the other side, it makes it a lot easier to fit the last strips.
I'll try to post a pic.
Image
Image

You should be able to see, how I 45ed the strips, so they fit in as several pieces. I was also able to throw a little design in. The very center piece was pretty easy.
Just food for thought !

Keep at it !

Jim
Keep your paddle wet and your seat dry!

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Re: Non-Bear Mountain Designs

Post by Cruiser » Thu Dec 22, 2016 11:16 pm

The cord or tubing will address the strips pulling apart and pretty much eliminate the need for those clamps.

If you are going to use the cord/tubing, just remember to get a couple of lengths of 1/4" dowel for the top/cove, so the cord doesn't damage the cove edges.

The sequence I use is:
- glue to strip
- strip to boat
- straps tightened just enough to pull strips to form
- dowels in place
- apply cord with sufficient stretch to pull strips together
- "wiggle strips all along the length to make sure seated well
- hand tighten up straps, let sit for however long your glue requires

- rinse and repeat (although I don't rinse, I just let the glue skin over and I use a small putty knife to skim the glue off)

Good luck and have a great Christmas

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