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Hi guys I'm building the woods flica 34' catamaran. I've finished cutting out the bulkheads and I'm going to be adding the 1"x3" timbers to frame the bulkheads. The build is plywood and epoxy. I'm planning to construct the strongback. The plan calls for 2 long 2"x5" timbers spaced 600mm apart and 2"x2" timbers to support the bulkhead pieces. I am planning to use a laser level to make sure everything is level and square, do I also need to use the plumb bob/spirit method (as detailed in the Gourgeon brothers book) or is the laser level enough?

I have a flat piece of raw land that I will be leveling, putting a layer of gravel, a tarp and then building the strongback on top of that. I have four tall concrete walls but no roof, I was thinking of just putting a few heavy duty tarps on top of crossbeam timbers to act as a temporary roof to keep off the rain and sun. Any suggestions for improving the setup would be greatly appreciated!!

Thanks so much in advance!

And special thanks to Fallguy for introducing me to this amazing community!!

Hello Ron-

I recommend you use something wider than 5" for the strongback. And don't built it until you frame a cover.

The laser is the best. You want it on a tripod.

I also recommend a high quality and new 4' level. I bought an Empire from HD for about $150.

Drill your laser guideholes at 3/16 or 1/4". You will find it challenging to get the light through, but eventually you will.

Submit some pictures of the build site. I am a fairly knowledgeable builder and can advise what I would do at least. I think you said the walls were 5' high, but not sure length or width.

Get the build site covered before you go much further. If you buy some commercial trusses; you can windbrace them and sell them when done and not lose too much money for common sizes, but 5' is pretty low and you almost need to stub an 8' wall up for that or find a hoop tent that could work.

The Tijuana sun will destroy your epoxy in about 60 days!

It will yellow, weaken, and chalk out.

Use these for ground anchors woth short 4x4 uprights. I would use either a 2x8,10,12 for the strongback. 2x12s are nice for scaffold planks later

https://www.amazon.com/CRIZTA-Anchor-Gr ... ljaz10cnVl

You will need to take eqch hull to painted before starting the next step to protect them from sun damage.

Thanks Fallguy!

Two of the walls are 15' tall, the other wall is the side of the house which is over 20' tall (see attached photo). I was thinking of building a simple wall frame out of 2x4's in the middle (red in the photo) and then attaching heavy duty tarps (blue in the photo) from the concrete walls to the wooden wall. In case of rain, the water will all collect in the middle and i was thinking of collecting it into a half cut 4" pvc drain pipe.

Also for the strongback how do you recommend I attach the 2x12" timbers to make 34' total? Scarf joints? Or overlap the timbers?

Thanks for all the advice!!!

Just get 6 timbers 2x12 12' long and lap them. Install four or 8 post anchors into the ground with 4x4s. The strongback doesn't need to be straight; just fairly level. The frames need to be installed straight and perfectly level to a hole in the waterline.. Keep the strongback timbers about 2 feet apart or 3.

For your picture, try it again. Once you figure out how; posting pics here is ez.

Hi,

I'd just say spend the time to make sure the strongback as level and accurate as possible.

i owned a fiberglass Woods Meander but there was a lot of plywood and timbers in the bulkheads / decking. Feel free to ask questions here. I also cruised Mexico on 2 different boats for about 3 years total and loved the country and its people. Can't say enough good things about it.

Evan is right. If your strongback is not level; you need to do a lot of shimming and shimming is less than ideal.

By the way, I epoxied the shims in on my build as we did have a few and I did not want them to fall out and the jig to fall.

Today I glued some timbers to bulkheads, did roundovers with the router on the stringers, and cut out notches in the bulkheads for the stringers. Fun times.

To join the hull panels, Richard Woods suggests just using butt straps to simplify the process but I could scarf the hull panels together as well. I scarfed the keel panels with the router and a jig I built, but the jig would be too small to scarf a big sheet of plywood. Do you guys recommend scarfing the hull panels and what is your preferred method to scarf them?

I am currently planning the build site still, and I was wondering what is the best way to turn the hulls over? I was thinking of using 2x4s to build a temporary roof covered with heavy duty tarp. I would have to make it strong enough to flip the hull.

Thanks for all the help and advice guys, I really appreciate it!!

Butt seams are acceptable, but I would probably build a scarfing jig and scarf 8-12 to one.

If you butt seam or scrarf; make sure the panels are aligned perfectly straight. I have seen where guys are not careful enough and the joint moves.

Shipping tape works well for releasing. I buy gorilla 2" wide ship tape and use it here whenever I don't want epoxy to stick.

So, for the edge of a board used as a panel dog to keep things straightt; you put a piece of tape there..

The best way to flip the flica hulls is beer and friends.

Skoota32 hulls are about 1200 pounds or more to 1600 to flip. I built a homemade gantry with timbers. We used 4 harbor freight manual chain hoosts and had a lot of control that way and one man would be able to flip alone.

Two by fours will be pretty weak unless built as a truss. You moght consoder building some really beefy turning rafters into your tent frame from something bigger if u can't find a flipping team. I would find some clear 2x10/12 and make a couple monster rafters, but manpower is best.

I just didn't have great faith flipping 1200-1600 pounds. Any idea on hull weights after sheathing?

Thanks Fallguy!! Did you only need a single gantry at the middle of your hull to flip it or did you need multiple gantries? What size timbers did you use to make the gantry, 2x12's?

Also can I plan to re-use the strongback for the second hull or should I plan to build a new one for the second hull?

Thanks again for all the help I really appreciate it!!!

mariobrothers88 wrote: ↑Tue Dec 15, 2020 10:54 am Thanks Fallguy!! Did you only need a single gantry at the middle of your hull to flip it or did you need multiple gantries? What size timbers did you use to make the gantry, 2x12's?

Also can I plan to re-use the strongback for the second hull or should I plan to build a new one for the second hull?

Thanks again for all the help I really appreciate it!!!

Our gantry is a double. Five feet apart. The legs were made with triple 2x6s nailed together. Two legs each side. A 2x12 for the 5' span and two 2x12s with joist hangers 20 feet long. The legs have 2x6s in two places bolted to keep them together. Ours is on wheels to deal with the small space margins. The building is 36' and the boat jist under 34.

The five footers are actually 8' timbers and the 20s are hung like a deck board in joist hangers. I was worried about them pulling out and also wrapped some galvanized pipe strapping. In order to avoid sideways torque, I also installed a 4'x5' board under the bottom.

Mine also has a 5" i beam on each one for a trolley.

My back did a number on me. I'll get you some pics if I can walk.

Here is how someone recently scarfed full sheets using a router and a simple setup:

cracked_ribs wrote: ↑Wed Nov 11, 2020 8:14 pm Today was overcast but not rainy so I dragged the plywood out onto the deck and beveled it for the controversial scarf joints!

That's most of what I got done today, but it's slightly fiddly work and I had to do a fair bit of cleanup afterwards so it ate up a big chunk of my day.

I started off by mounting a router on a piece of leftover hardwood flooring...I just punched a hole through the center and then countersunk a couple of machine screws using the router itself.



That let me bulk off the majority of the wood just by clamping a couple of straight boards to either end of the wood.



The areas I couldn't hit with the router, I knocked down with a plane until they were roughly in shape, and then fine-tuned it all with an orbital sander. I don't like to overthink this stuff, I just get it into shape and let the glue do the work after this.





I kind of like the look of the multi-toned plane curls.

The glue-up was a bit further into his build thread: cracked_ribs CR16 skiff build thread

The 2x12-20' are 3x.

Forgot.

In order to build; you have to use 2x jacks to get the legs up. Hard work.

BrianC wrote: ↑Tue Dec 15, 2020 11:54 am Here is how someone recently scarfed full sheets using a router and a simple setup:

cracked_ribs wrote: ↑Wed Nov 11, 2020 8:14 pm Today was overcast but not rainy so I dragged the plywood out onto the deck and beveled it for the controversial scarf joints!

The glue-up was a bit further into his build thread: cracked_ribs CR16 skiff build thread

Yeah I may be one of the few scarfing fans around here. IMO it's pretty simple on plywood and I like it as a joining method.

Subsequent scarfs, when I had fewer to do, I just did with the plane and felt it was about as fast as setting up the routing jig etc. But your build is so much larger, the payoff of setting up a jig to rout yours might have more benefit.

If you have any questions, feel free to ask.

Thanks Fallguy for the awesome response!

If I can get a flipping team then I won't need to build a support structure/frame with manual chain hoists? How many people would I need?

Thanks again to everyone for all the great responses!

Calculate the weight of the hull.

50 pounds per person is a reasonable maximum

If that is too heavy for an 8-12 person crew, another option would be a rolling cradle.

That would be where you build a big cradle around two places in the boat and she can be rolled carefully in it.

Thanks Fallguy!! I already bought 12 units of these 15"screw in earth anchors : https://www.grainger.com/mobile/product ... P:20501231

Should I still buy 4x4s and post anchors or can I just use the screw in earth anchors? I was thinking of putting in 6 screw in earth anchors on each side would that be enough?

Thanks again for all you help!!

fallguy1000 wrote: ↑Sat Dec 05, 2020 12:19 pm Just get 6 timbers 2x12 12' long and lap them. Install four or 8 post anchors into the ground with 4x4s. The strongback doesn't need to be straight; just fairly level. The frames need to be installed straight and perfectly level to a hole in the waterline.. Keep the strongback timbers about 2 feet apart or 3.

For your picture, try it again. Once you figure out how; posting pics here is ez.

Hey guys I just completed these frames. I'm going to be attaching tarps from the concrete walls to the frames to keep out the sun/rain. I'm going to be buying the lumber to make the strongback tomorrow, will probably buy 6 units of 2"x10-12"x12' and attaching them with half lap joints. Do you guys have any recommendations to make the length of the half lap into the 2x12 or 2x10? I was thinking 12". Also is the best way to join them with screw AND wood glue or would screws alone be enough? I wanted to reuse the strongback for the other hull so I want to be able to disassemble it pretty easily by using just screws, but I'm worried the strongback might move.

Just get 2 16' and four 12' and lap as desired; never like a 1' overlap it can get hinky in the weather and screws closer than 4" tend to split the boards; nothing epoxy can't fix, but movement...

Hey guys I ended up laying a concrete level pad because I had difficulty finding good quality wood to make the strongback. The plans say: "If building on a flat concrete floor, 3"x3" wood blocks can be bonded to floor using a runny polyester-filler mix, or car body filler." I bought Bondo fiberglass resin from walmart. When it says "polyester-filler mix", am I suppose to mix the fiberglass resin with a filler like fumed silica, or should I just use the Bondo fiberglass resin (with hardener of course)? Also, since I know polyester resin doesn't bond well to wood, should I precoat the 3"x3" wood blocks with the Bondo resin first before glueing it to the concrete?

Thanks for all your help guys, I truly appreciate it!!!

The bondo is used on its own. There is no need to precoat. If the bondo let's go, just make a runnier thickened mix of epoxy. The blocks will break the concrete before they come off with the epoxy method.