Nut shell pram problem

[LenD.]

I can't find a sheet of marine ply in ontario 4x10.
I could build the 7.7 vrs the 9.6 model with 4x8

Scarfing ply was mentioned for the 9.6

Any thoughts ???? I want it as a tender for my boat.

[Rich Jones]

Does anyone make 4X10? I've always scarfed mine from 4X8. A bit of work, but very strong when done right.

[LenD.]

yes they do make 4x10
is scarfing difficult?

[Lewisboats]

I swear I replied to this thread... Oh well...!
Try these folks:
http://www.worldpanel.com/Index.htm

They might ship from the Michigan site.

I quote:
5 x 10 & 4 x 8 Okoume BS1088 available for Hull construction and Interiors...9mm is 7-ply, 12mm is 9-ply

[Lewisboats]

Aha! found it...don't start another thread about the same thing if you don't like the answers in the first one. Irritating it is! You've also gotta give it time for people to give suggestions. Not everyone is glued to the computer all the time.

[LenD.]

Sorry for the second thread, I am not being impatient, I thought a new thread was needed if I was looking for information on scarfing and which pram to build the 7.7 or the 9.6. Any info would be benefitial. And thanks for all of the info so far. Noah's sells a scarfing jig or tool that attaches to a circular saw. Anyone try this method??

[StevenBauer]

There is no need for a scarphing jig if you are just building one boat. It just takes a few minutes with a block plane/belt sander/powerplane. 4x10 plywood costs like double the price of 4x8. If you can find it.

We've used a 9'6" Nutshell Pram as our tender for two seasons now. My daughter built it with a little guidence from me: www.woodenboat.com/forum/showthread.php?t=80582
It's a very capable boat. I'm building a smaller tender that we'll use if it's just 1 or 2 people going to the boat and to take with us on our weeklong summer cruise. We'll still have the Nutshell for when we need the extra capacity.


Steven

[Candyfloss]

What Steven said. Scarfing is easy, 10ft ply very expensive.

9ft6 is a lot of dinghy. Bigger is not always better.

[Breakaway]

I'm in the middle of building my first small boat, a 12-footer, so I'm new to it all like you. I just followed the common scarfing directions and used a block plane. Was easier in the doing than thinking about it. DO make sure your work table, surface is very stable and rigid. Then just go for it.

[LenD.]

What are the common scarffing directions? Is there a site you found the info on. I have seen at least 4 different ways to scarff plywood. I only have two sheets to scarff together.
Thanks

[Songololo]

See this thread (http://www.woodenboat.com/forum/showthread.php?t=96610) for how I did it using a block plane. If you use either this forum's search function, or even better, use a Google search on this site using the word 'scarfing', you'll come up with heaps of infornation.

[Cuyahoga Chuck]

It's called "stair-stepping". You figure out the the width of the scarf. I use 8 times the plywood thickness i.e. 2" for ¼" plywood.
Clamp the bottom sheet with it's scarf edge to the edge of a flat topped bench. Scribe a line 2" up from the scarf edge. Place the second sheet on top and match it's edge to the 2" line. Scribe a second line 2" from the scarf edge of the top sheet and clamp it down.
Sharpen your plane and keep your stones handy. The glue in the plywood can take the edge off your plane iron quickly.
The object of the planing operation is to cut a continuous flat from the 2" line on the top sheet down to a feather edge on the bottom sheet. When you are finished you will have a flat 4" wide 48" long flat at about a 7° angle with the table top.
It takes time to do a whole 4 foot scarf. I usually do it over two days. I rough it out the first day and on the second I sharpen my planes and do the finish cuts. The finish cuts are very important and I don't like doing them when I'm bagged out from all the rough planing.
Be forewarned that you have to be aware of which ply faces are the As and which the Bs. To make the proper scarf angles so the A faces and B faces match up you have to stack the sheets properly. If the bottom sheet has the A face up the top sheet should have the A face down. When you are finished You should be able to pivot the top sheet over . The faces will match and so will the scarfs.
I haven't hand cut scarfs for a couple of years. I hope my memory hasn't failed me.
Good luck

[Breakaway]

What they said: thats how I did it--although I wish I would have been aware of that centerline mark tip of Songolo's. I've seen threads in which others have used belt sanders and even grinders to cut the bevels.

[Candyfloss]

Easier still to rip your ply down the middle & scarf only 2ft wide, provided your plank layout will allow it, i.e. you have an even number of planks.

[LenD.]

Thanks for all the excellent advice and the great pics. I am just going to start and let the chips fall where they may. I will try and send some pics in of the project. I am building the 9.6 pram

Thanks again

[gazzer]

Scarfing is a piece of cake after you've done a few. On my latest build I tried router jigs, circular saw jigs, belt sanders, portable planers ... you know, all of the things that take time to set up an make things much more easy. About half way done, I basically was marking the scarfs on the planks (I did them individually instead of whole planks - it seemed more efficient), stacking them, and then using the power planer by eye to get close. I finished using a jack plane followed by a block plane to get to a feather edge.

A few scarfs did not go as well as expected; however it is simple to remark the plank back an inch or so and have another go at it. The key is to know how to sharpen your plane irons, the rest is easy.

Good luck, my nutshell is now 23 yrs old and still brings a smile.

-G

[LenD.]

Is this where I would post pictures of my progress or do I start another thread.


Thanks

[StevenBauer]

Is this where I would post pictures of my progress or do I start another thread.


Thanks

That's up to you. Some folks start 27 thousand threads about one project and some people keep it all on one thread. You've got pics? Let's see 'em. :)


Steven

[sismcq]

I lost my 10' Dyer Dhow in a storm. I still have the rigging, etc. (mast, tiller) I decided to build a Herreshoff pram, and convert it to a sailing dink but dont know exactly where to place the mast and centerboard. Any ideas? (It has 1 sail)
thanks, Sis

[LenD.]

Would like to send pictures but I can't seem to get them to work.

Len

[LenD.]

http://photobucket.comlen01

[Hwyl]

You have to put the pictures on a hosting site light photobucket and then link the pictures to here.

choose the direction that says "share image" and just paste it in your reply

[LenD.]

I have pics in photobucket but can't get it to this site ???

[LenD.]

http://i1019.photobucket.com/albums/af311/lendow1/pram003.jpg

[LenD.]

http://i1019.photobucket.com/albums/af311/lendow1/pram004.jpg

[LenD.]

http://i1019.photobucket.com/albums/af311/lendow1/pram015.jpg

[LenD.]

Thanks for great advise, here is where the pram is at.

Len

[StevenBauer]

Looks great, Len. You're getting to the fun part. :)


Steven

[bob easton]

Have you done any scarfing yet? I'll add one tip. The whole exercise becomes a lot easier if you can stack up 4 pieces of wood. With only 2 pieces being planed, you have to do a lot of guess work to get the correct angle. When 4 pieces are stacked, there are enough edges stacked up to automatically yield the correct angle. A plane will easily ride along those "stair steps," magically producing exactly the right angle.

So, instead of one 4 foot wide scarf of 2 pieces, if your planks can fit on 2 foot wide boards, stack up 4 boards and start planing. Easy Peasy.

BTW, that laminated frame is looking very nice! ... but ya need more clamps ...

[LenD.]

http://i1019.photobucket.com/albums/af311/lendow1/P1030466.jpg

[LenD.]

New Pic from the frame to a Hull, Yes on the scarfs, you can see where the scarfs took place. Moving on to the fun bits.
Len

[LenD.]

http://i1019.photobucket.com/albums/af311/lendow1/P1030469.jpg

[LenD.]

I have one problem. If you look at where the gunwales are to be added the ply dips inward at the frame. When I add the mahagany gunwales with clamps the boat takes on the perfect shape, however , there is a lot of pressure to shape the hull. Anyone else ever have this difficulty?

[Reef_Kringle]

I think Harbor Sales in Maryland will ship you some 4x10. I've been thinking about building a sailing tender for my humble classic yacht. That Acorn sure is a beauty. I'd probably have to beat the neighborhood kids away from it.

[StevenBauer]

I have one problem. If you look at where the gunwales are to be added the ply dips inward at the frame. When I add the mahagany gunwales with clamps the boat takes on the perfect shape, however , there is a lot of pressure to shape the hull. Anyone else ever have this difficulty?

I don't remember that happening with our Nutshell. If it looks fair when you add the gunwales I'd say just go for it. I think it will be OK. You're making some great progress.


Steven

[ejds]

http://i1019.photobucket.com/albums/af311/lendow1/P1030469.jpg

That is how mine looked like when I turned it over. I did forget to bevel the station molds, could be a result from that. Adding the gunwales smoothed things out.

[Jeff Benagh]

Do the Nutshell plans have a cross brace at the top of the frame? The Shellback does and it uses nearly the same construction method. The brace is only while building but kept in until the gunwales are in, IIRC. This picture shows a little of the effect you mention, but it certainly disappears later:
http://jbenagh.smugmug.com/Boats/Shellback/DSCN0102/160025148_EeTHS-XL.jpg

Jeff

[FSS172]

That is how mine looked like when I turned it over. I did forget to bevel the station molds, could be a result from that. Adding the gunwales smoothed things out.

Hi Len - My son and I each built this boat a couple of years ago. He had this issue with his; I didn't. I don't think it has to do with beveling the molds. IIRC, the molds are not designed to be beveled and don't need to be if they're positioned correctly on the jig. I think this has to do with the vertical positioning of the sheer strake relative to the midships frame and the end transoms. Too low in the center and/or too high at the ends would result in this geometry I think.... His unfairness did resolve with the installation of the gunwales although it took some effort to bend them in as you have experienced. I'd guess that changes the overall shape of the boat a bit but it doesn't seem to affect the appearance, performance, or his enjoyment of the boat significantly. It also may build a little stress into the structure and I've wondered about what the effects of that might be over the life of the boat... But we've decided just to go sailing and not worry about it! :D It seems to be a very forgiving design in just about all ways!

[James McMullen]

If the gunwales bring it back into a fair curve then you'll be fine. Don't worry, you're on the home stretch! Go, Len, go!

[ejds]

Hi Len - My son and I each built this boat a couple of years ago. He had this issue with his; I didn't. I don't think it has to do with beveling the molds. IIRC, the molds are not designed to be beveled and don't need to be if they're positioned correctly on the jig. I think this has to do with the vertical positioning of the sheer strake relative to the midships frame and the end transoms. Too low in the center and/or too high at the ends would result in this geometry I think.... His unfairness did resolve with the installation of the gunwales although it took some effort to bend them in as you have experienced. I'd guess that changes the overall shape of the boat a bit but it doesn't seem to affect the appearance, performance, or his enjoyment of the boat significantly. It also may build a little stress into the structure and I've wondered about what the effects of that might be over the life of the boat... But we've decided just to go sailing and not worry about it! :D It seems to be a very forgiving design in just about all ways!

In our racing group are some Nutshells that are about 20 years old and it doesn't look like it is an issue.

[LenD.]

Thanks for all the good advise. I am going to keep going with the gunwales. Will send pics with next step

Thanks again
Len

[coelacanth2]

Mine ahd a little bit of a hard spot just as you have pictured and applying the rubrails made that disappear. I've got my little stuff curing in the basement, going down to round of the tips of the spars and put the bee-hole in the mast. How are you coming on that? yours looks quite nice.

[peter radclyffe]

a bit late but hey

Helpless

No 4 x 10 marine ply in north Ontario
So 4 x 8 seems the way to go
Make a jig, take your time
Tapered scarf 8.1 ratio
A little change should get you there


Decent strong clamps behind the grain
Slow epoxy on the rise
Expletives flying across the room
Watertight seams before your eyes
Wont leave you
Helpless , helpless

[peter radclyffe]

i wrote this when i saw the thread this morning, then i was about to post it,
& read the rest of the thread, & realised you had already built it, so i sent it anyway

[LenD.]

Just starting up again send pics soon

[GNat]

Today I got the 5th - and as far as I'm concerned final - coat of paint on the bottom of my Nutshell. Also a second coat of epoxy on the keel/skeg. So I hope to turn it all over and finish the inside in the next few days. I didn't have the in and out curve problem with mine so I guess i'm posting this just to say that I'm another Nutshell builder in progress and looking forward to seeing more pics of yours. With the painting: If i was doing it again, I'd spend a lot more time getting the boat fair and smooth BEFORE going on the the primer coat. I added a fibreglass tape over each chine and it took a lot of sanding and filling to get the tape edges to fair out. Then the primer coats had to get sanded because I hadn't got it as smooth as I thought and then the top coats showed up the flaws even more.

[troutman]

scarfing and cutting gains seem intimidating but as you do them they seem very intuitive. sharp tools are really important. my little lie-neilson block plane is in a holster on my belt and the spyderco ceramic stone is close at hand as my Arch davis Sanddollar approaches completion.

[LenD.]

http://s1019.photobucket.com/albums/af311/lendow1/?action=view&current=P1050186.jpg

here is where its at

[LenD.]

http://i1019.photobucket.com/albums/af311/lendow1/P1050186.jpg?t=1307927396

I think this posted without going to photobucket
Seats next

[Polly]

Condon Lumber in White Plains, NY stocks 4 x 10 - I'm not sure if they ship, though.