PDA

View Full Version : Robb White Sport Boat build.



swmn
01-17-2017, 12:49 AM
Going for it.

Here is my old Grumman Sport Boat:

http://i.imgur.com/5S4h96P.jpg

Just about perfect for my needs, this one was +/- 1980 production. Been caribou hunting with my sons. Been camping with the wife. Works pretty good with the 4 stroke Honda 5 on there, tops out at about 11 mph.

I have some housekeeping to do.

swmn
01-17-2017, 01:04 AM
There is, that I can find, only two extant RWSB build on the 'net.

A youtube with some related videos... https://www.youtube.com/watch?v=k1Sf5MbOg_Q

Guy on wcha dot org ... http://forums.wcha.org/showthread.php?6937-Robb-White-Sport-Boat

I emailed the webmaster of Kurt's website. His RWSB is no longer listed among the boats he has built. I noticed he hadn't put the floor futtocks in yet when he painted the interior, I got nothing.

The you tube is kind of a hot/cold thing for me. I am probably going to duplicate the way they attached the cutwater. I don't understand why that builder did half the hull with Titebond 3 and then switched to cyanoacrylate superglue for the second half of the stripping.

I intend for this thread to more or less duplicate my lately finished Tiny Titan build thread. I am planning to bring you guys the problems I am facing from my moaning chair, show the path I choose to solve the problem and get on with it. Looking to make it easier for the next builder.

swmn
01-17-2017, 01:19 AM
I am going to go ahead and tag @WesWhite now. eeek, no tagging function. I plan to build as Robb White specifies in the plans I bought with a couple exceptions.

I am going to use mahogany rather than poplar for the interior futtocks.

I am using Sapele instead of poplar for the transom.

I am going with 8 floor futtocks and four sheer to sheer frames (mahogany) instead of 8 floor futtocks and three sheer to sheer frames in poplar.

I am going to use mahogany instead of poplar for the runners under the boat.

I am probably not going to fool with the full round/ half round inwales Mr. White was so fond of. They look like a LOT of work, I am likely to go with 1/4" inch spacer blocks with rounded corners and 1/4" x 1" inwale. Probably mahogany.

I do have a couple test panels going. Talked to gouegon tech support today. I notice when I heat the strips and epoxy on my test panel as described by Mr. White I get a cloud of white smoke shortly after the epoxy thins out and starts running. I am informed I need filters on my respirator that can handle "organics.", so I got some of those coming from amazon.

Preliminary results on my test panels suggest Mr. White actually knew whereof he was speaking. The test panels are not finished, both are bare on the outside, but the one built Mr. White's way is strong like a brick outhouse already. I wonder if the first guy to carvel plank a collection of frames got burned at the stake as a heretic.

I am not going to give away Mrs. White's retirement income. There is plenty of info in the last interview of Mr. White to heat your own shop up to 130dF and epoxify at will.

swmn
01-17-2017, 01:22 AM
Here is a look at Clear Creek in the Tanana River flats. From Fairbanks, Alaska, proceed west (down) the Tanana river abotu two miles from the airport. Turn left (east) into Salchaket Slough. After about 3/4 mile, turn right (south) into Clear Creek.

This spot is 2 road miles and 4 river miles from the computer in my home office I am posting from right now.

http://i.imgur.com/3yw6AHR.jpg

swmn
01-17-2017, 01:26 AM
Transom is quarter sawn Sapele. Going to the millwork shop tomorrow for planing down to 9/16", it is at 13-14/16 right now.

three pieces glued up from the side at 22x36 inches, finished transom will be 16x32.

http://i.imgur.com/QNtHe9I.jpg

Head on I got some chatoyancy going on. her name will be Joy.

http://i.imgur.com/xK0vPU0.jpg

I trimmed off the bottom in the above pic to take the width down to 16 7/8" so it will fit through the planer, scrap for planer skip on the right. Once I get it back I'll cut out the curvy transom shape, plane the dish and bowl, and get busy epoxifying...

swmn
01-18-2017, 11:50 AM
One other resource to round out my top three online resources for this build is a 10 year old thread here, that contains some pics of the last Sport Boat that Mr. White built, and what I think are the last posts by his son Wes White.

http://forum.woodenboat.com/showthread.php?60471-Robb-White-Sport-boat

If Wes were to show up, I have two questions.

1. Does it really matter what order I do the glue up once I have all the strips on the forms?

I am an evening and weekend builder. To follow the plans exactly I think I would more or less have to take a week's vacation to follow the plans exactly. I think I see how to break it down into smaller chunks that will fit my schedule. I intend to end up with a boat that is true and fair with no pieces missing.

2. Epoxifying. What does good job look like? What does too much heat look like? What does too much epoxy look like. How will I know I am doing it right?

Home sick today shedding virus particles if anyone wants some. Once the wife clears the garage I plan to continue with experimental epoxifying today.

swmn
01-18-2017, 07:21 PM
No epoxy work today, -44dF outdoors, I am struggling to keep my garage shop at +65 to +68dF.

I do have two test panels in progress.

http://i.imgur.com/xonYUaE.jpg


These are both of the starboard quarter, blind spot when tiller steering, the place where my Grumman had the most dents. Strips are Western Red Cedar; and used, they came back off a canoe I started and have a bunch of random staple holes in them. Each panel is near enough to 16x16".

The one on the left is typical strip canoe construction. Continuous bead of Elmer's Carpenter's Glue along every cove, outside is faired for 6 ounce fiberglass after the weather breaks and I can get the shop warmer.

The one on the right is the same durn thing, except I used spots of superglue every 8" instead of wood glue, and I have done my best to "epoxify" it from the instructions I can find. That black spot near the middle of the epoxied panel is an old screw hole. I used 105/207.

Here is another look at the two panels. The canoe panel, above in pic shows the turn of the bilge in the cross section. The epoxied panel is now showing the outside surface.

http://i.imgur.com/UazipFn.jpg

Plenty of epoxy oozed through, even though I used a LOT of cellophane packing tape on the outside surface to minimize leak through.

Closer look at the outside of the epoxied panel, including the screw hole from before:

http://i.imgur.com/eUXTSrI.jpg

That old screw hole is sealed up real nice. Smooth to the cello tape on the outside, and just a wee dimple on the inside of the hull, just like Robb describes. So I got that part right.

However, I had a (relative) metric butt ton of epoxy leak through the panel into the tape and on to the outside of the hull.

I am going to try some different taping methods on the inside of the canoe piece so when I glass it I don't make a big mess.

Getting the cellophane tape off the outside of the hull after it was more or less epoxied in place was a bit of bother too. More experimentation here.

So far I am pretty optimistic that I can build an epoxified panel glassed on the outside of the hull both lighter and stronger than typical stripper construction glassed both sides. Once I get the hang of it I suspect the PITA factor will be similar. I am willing to put up with a fair bit of foolishness on the outside of the hull in exchange for not having to lean over and reach in and spend a bunch of time fairing the inside of the hull.

If I wasn't optimistic I would stop experimenting now and build standard stripper technique.

upchurchmr
01-18-2017, 08:19 PM
You certainly can make the panel lighter with only epoxy on the inside, instead of glass both sides.

However, the glassed outside only panel will break easily whenever you hit something in the river.
When you hit something on the outside, the inside breaks by being punched into the boat.
This is where glass increases the strength a great deal.

The other thing you should do is try to bend the panels toward the outside.
This puts tension on the inside surface of the wood. When it bends parallel to the grain, you have the wood at its weakest direction.
Epoxy does not add a bunch of strength, it just holds the glass and wood together so each can add their strength.

Good luck with your tests.

swmn
01-20-2017, 12:55 PM
A fly in the ointment. After fairing and sanding and then wiping down real good with isopropyl, some of the staple holes have sanding dust trapped down in them.

http://i.imgur.com/UikYEPU.jpg

I don't like it. In the directions with the boat Robb says he prefers to use #4 screws to fasten strips to station molds. He says you can use box nails, but they are hard to remove without scarring the cedar strips. He doesn't mention staple guns one way or the other.

I was thinking the stripping would go really quick using an Arrow T-50 with half inch staples. May have to rethink that, I'll try a little harder to get good epoxy flow down into staple holes on the next panel, but I thought I had done a pretty good job on this one.

upchurchmr
01-20-2017, 01:04 PM
Most people use a manual stapler and put the staples in thru a strip of plastic.
The plastic makes it easier to pull the staples without gouging the wood by pulling up on the plastic

If you do get some gouging it is possible to spray the damage with water.
The cedar normally swells out to almost flush. Depends upon how much damage there was.

If you get the staples lined up it makes it look more like you intended the way it looks.

swmn
01-20-2017, 01:39 PM
Most people use a manual stapler and put the staples in thru a strip of plastic.
The plastic makes it easier to pull the staples without gouging the wood by pulling up on the plastic

If you do get some gouging it is possible to spray the damage with water.
The cedar normally swells out to almost flush. Depends upon how much damage there was.

If you get the staples lined up it makes it look more like you intended the way it looks.

Appreciate the constructive criticism. Really.

I get that almost no-one is using this method. I do think it is worth exploring before I choose to build the boat in a way other than specified by the designer. Thanks for not judging.

FWIW I put some strips of duct tape near the mouth of my staple gun so the 1/2" staples run through the 1/4" strips, penetrate the mold station about 1/8" and stand proud of the cedar planking about 1/8". It was a tip I read in one or the other of the strip canoe books. Works great, I have a pair of mini needle nose pliers, maybe 4-5 inches long that can reach under those staples without touching the wood and pop them right out.

I'll look into plastic strips to run staples through. I do agree, even on a painted boat, the workmanlike thing to do is make the staple holes line up in an orderly fashion.

I am ordering a stack of reprints from MAIB to look for clues to epoxification. A lot of the article titles attributed to Robb are familiar as chapter titles in book format. Others aren't so familiar. Waiting on a call back from Bob Hicks to see if he can think of other articles I should order that don't seem likely from the titles. I'll probably send along a few extra bucks so he can just send me other reprints neither one of us thought of for my first order.

Cold snap here is over, only -15dF this AM with the garage loop of the furnace running near full duty cycle my thermometer was just kissing 70dF. I bumped the thermostat up a little bit, but really 48 hours at +70dF isn't going to reheat my resin or hardener all the way through.

upchurchmr
01-20-2017, 01:51 PM
I don't remember if anyone suggested the Gougeon book on Boat Construction.
Here is the free download. It's been one of the first and best books by some guys who pioneered and built lots of boats, large and small.
http://www.westsystem.com/ss/assets/HowTo-Publications/GougeonBook%20061205.pdf

Lots of how to tips at their web site: http://www.westsystem.com/ss/how-to-use/

Under their Projects page there is lots to read.

Did I previously mention Nick Schade's website for hints and videos? http://www.guillemot-kayaks.com/guillemot/information/boat_building_making_kayaks_canoes_and_small_boats/free_boat_building_videos_stitch_and_glue_strip_bu ilt

You might watch out for older articles, there has been some development since the original canoe "how-to" books came out.

swmn
01-20-2017, 02:34 PM
User epoxyboy here linked me to the gougeon book during my first build. It's in my phine twice, all 412 pages. Once in the factory memory and once in the sd card.

Ill check out the other two links. I did read up on kayaks, gosh 15 years ago or so, dont imagine i am current.

Thanks.

Todd Bradshaw
01-21-2017, 12:06 PM
So far I am pretty optimistic that I can build an epoxified panel glassed on the outside of the hull both lighter and stronger than typical stripper construction glassed both sides. Once I get the hang of it I suspect the PITA factor will be similar.

Sorry, but this simply isn't going to happen, no matter how much you want it to, or how much you ignore the advice of folks who have actually built strip boats. A stripper is a cored composite construction and the vast majority of its strength and stiffness comes from the balance of tensile strength between its inner and outer skins. Your "epoxified" sample has a thick, sloppy, brittle, overly heavy and overly expensive coating on the inside that isn't going to contribute the strength the lamination needs to the project. Tensile strength on the inside of a stripper hull is more important than it is on the outside, as that is what has to resist the forces of beaching, hitting anything or pounding on waves when running at speed. Your thick, brittle resin layer has basically none. You are trying to re-invent the wheel without bothering to learn the process or what's important about it and your wheel is coming out square.

Gib Etheridge
01-21-2017, 04:16 PM
Or to put it another way, you're fantasizing that you will get the same strength, rigidity and stiffness from a "T" beam that you can get from an "I" beam of the same height, widths and thickness. It just will not happen.

Your testing process is admirable, and you're wise to do it. Perhaps you should compare the qualities of a panel glassed on both sides to one glassed on one side and glued on the other side only. That will be enough to convince you.

I'm like you, to a degree, I don't always want to conform, and sometimes I come up with improved ways of doing things, but sometimes the evidence is irrefutable. You must realize that if you refuse to believe the evidence and continue to deny the facts you will have lowered yourself to the same level as those who voted for Trump. :arg That's not safe or sound practice when building a boat (or voting for a leader) that could kill you and yours when it fails. It's your responsibility as an adult and a guardian to do it right.

swmn
01-21-2017, 08:40 PM
Gib, Todd, thanks for your points of view.

1. My opinion is that Robb White believed in himself and his boats.

2. My experience here is seasoned builders are constantly admonishing new-ish builders to follow the designer's instructions exactly and not go adding extra parts to make the boat stronger and heavier.

1 and 2, for this build, are in direct opposition.

I had a thread going in design/plan, doesn't need to be rehashed here, talking about stripper techniques that resulted in my opening this build thread now with test panels. I think this sort of planning and evaluating has kept some (a few, lots?) of folks from taking on the build. Its a great little skiff for protected waters as built by Grumman, and Robb nailed the two main problems with it; too much rocker to plane efficiently and not hollow enough in the forefoot to go upwind in any kind of chop.

So I am building the thing. It is going to be at least as good as my GSB all around, plane better, not root into waves and hopefully be able to go upwind.

I understand the theory that fiberglass inside the hull keeps the wood from splintering in response to rocks outside the hull and fiberglass outside the hull protects the wood from splintering when you got the American Canoe Beer thing going on.

So two items.

My first epoxified panel, pictured above with too much epoxy on it, well here is the rest of the story. I pre-heated that thing until it was hot to the touch. I brushed on about as much 105/207 as you see on the surface now, and it was gone, just sucked right up into the wood. I brushed on a second coat about just as heavy, all but a teaspoon or so, gone in a few seconds, just sucked up into the wood.

So I brushed on a third heavy coat like that and apparently about none of that got sucked into the wood. I blew on it and blew on it with a heatgun, brushed it around, spent a bunch of time heating the staple holes and brushing hot epoxy to them and blowing on them some more, pretty much the third coat just sat on the surface and is still sitting there.

The best advice I got from Robb's published stuff is to keep feeding the wood more and more epoxy until has taken up all it will take up - but there is no published guidance from him to tell when the wood is about done taking up epoxy, no way to know when to stop adding more. He wrote in several pieces "[epoxifying] is hard to get right."

I ordered all the relevant back issues from woodenboat last night as pdfs and got no new clues. I got an index file from MAIB this am that I haven't opened yet. I am going to give the man his due before I build this boat conventionally.

item 2. Here is a picture of my first conventionally built test panel. It's Western Red Cedar and Elmers (yellow) wood glue, no glass or epoxy yet.

http://i.imgur.com/0P8VQai.jpg

Imagine the inkpen is a sledge hammer or a cinder block. Imagine I have achieved the 85/15 ratio, that is my panel is 85% as strong as theoretically possible given room temperature WRC, room temp 105/209 and room temp 6 ounce fiberglass, and a thorough multi-day cure +70dF or higher.

So from what height can I drop a cinderblock or an 8# sledgehammer to crush that inkpen without damaging the panel? From what drop height would the panel spring a water leak on the first insult? From what drop height will the test panel be crushed like a bug?

Thanks for your help.

upchurchmr
01-21-2017, 09:02 PM
Good luck,

You are consistently going down wasteful, inefficient, time consuming path, and it will not improve your boat.

With all due respect to the dead - the designer didn't know much about epoxy/ wood construction.

Sorry - I couldn't stand it. Do what you like.

swmn
01-21-2017, 11:17 PM
Thanks all.