Building a cataraft

Discussion in 'Watercraft' started by isaacfab, Feb 10, 2011.

  1. isaacfab

    isaacfab Member

    Okay, so I'm brand new to rafting, steelheading, fly fishing, and Washington. Okay so not brand new, I've been here for a year or so. I bought my first fly rod when I got here and am hooked for life. I bought a drift boat and have gotten some good use out of it but it is clear that there are some distinct limitations, like possible death if you get in over your head (not that I would ever do that).... Late last summer I was fishing the Rogue and got my first exposure to rafts and decided I had to have one. After quite a bit of research I have settled on a 16' cataraft.

    My intention is to update this thread as I build the cataraft over the next few weeks. First I want to make sure that I am not doing anything that is obviously wrong and second I want to give anyone looking to do this themselves a blue print (if there isn't one I didn't find already). BTW it will make its maiden voyage on the Yakima later this month.

    Okay so through the forum here and various places elsewhere on the internet I have gathered what I believe is enough information for a solid plan. Here is the set of parts that I am starting with:

    Aluminum Tubing 100' (5 x 20' lengths bought at local metal distributor, you can use chain link fence post if you want but it is much heavier)
    Cast Iron Pipe fittings Quik Klmap (got these from two places frontier play ($$$$) and the same ones from Farm Tek at half the price)
    Dry Boxes (frontier play, half the price of anywhere else)
    16' PVC glued tubes (Maxxon I think....the guy I bought them off of on craigslist said they were 'Bad Cat' but I have my doubts)
    Cam buckle straps (from McLendons)
    Anchor System (more to follow...)
    Oar Towers (NRS Short from frontier play)
    Oar Mounts (Sawyer Cobra from Sportco in Fife)
    Floor ( 10' x 34.5" from stitches in stuff in Colorado)
    Storage box (from Lowe's)

    Torque Wrench
    Miter Saw w/ metal cutting blade
    Lock Tite
    JB Weld

    So far I have measured and cut about 90% of the pipes and have loosely assembled the boat without any accessories to verify the measurements. Next step actual assembly. Attached are some picks from what I have so far.
  2. shawn k

    shawn k Member

    bad cat uses maxxon tubes.
  3. Ed Call

    Ed Call Mumbling Moderator Staff Member

    Oh, I'm gonna like this thread a lot! Nice start indeed! Welcome and one hell of a first post.
  4. isaacfab

    isaacfab Member

    That makes sense.... on the Bad Cat site they looked very similar to mine.

    Okay some more information. I have decided to make my frame 11' x 72" this is a little longer than most frames but after fitting it to the tubes I am happy with the flexibility it gives me with seating and storage. Also I have the floor dropped 8" from the cross bars and it is 36" wide.

    Today I have assembled the top section and the floor frame and connected them (see the pics). All of the exterior joints have been tightened with the torque wrench and loctite, everything else is just hand tightened so it can be adjusted later.

    The frame fittings I am using do not require any welding however the connections that will bear weight (cross bars to the floor frame) I use heavy duty loctite on the set screw and cold weld (JB weld) on the contact of the tubing and the fitting. The set screw is designed for a 2000lb load without slippage but it doesn't hurt to be careful (you could even bore a hole though the tube and fitting and use a long nut and bolt if you wanted to be extra careful).

    Just a quick word on fittings. There is a wide variety of fittings so I had to plan well before ordering. Also All fittings must be on the tubing before anything is tightened or you will be taking everything back apart.

    Also in order to cut the pieces to size I replaced the blade on my miter saw with a metal cutting disk, see the pic.

    Next step is to make adjustment for bays and seating. The plan is to have a front and rear fishing seats with the front seat large enough for two if need be. Lean bars may be a little tricky but we'll see.
  5. Steve Call

    Steve Call Active Member

    Very cool.

    How much does or is that frame going to weigh?
  6. Ed Call

    Ed Call Mumbling Moderator Staff Member

    Are the side tubes all one piece?
    Will you have cross rail spreaders spanning your drop down rails to keep that mesh cargo deck tight?
  7. isaacfab

    isaacfab Member

    I'm not sure how much it is going to weigh...However the reason for the fabric floor and aluminum dry boxes is for the weight issue. I did pick it up to put it on the trailer and would estimate about 100lbs right now (but keep in mind I am a stud so it could be much more ;). Now that's with no lean bars, seats or gear, I'm going to weigh it whole when I'm done.

    Yes the side tubes are one piece and there are three cross rails on the floor frame (front, rowers foot rest, and rear). Several of the frame fittings are ideal for running cross rails.
  8. Ed Call

    Ed Call Mumbling Moderator Staff Member

    Those tubes are gonna weigh a bunch too. My boat is HEAVY and loading it solo into the utility trailer when we do the family trips is tough. And mine has 14' tubes. My decks are load bearing plywood sealed in Line-X, so they are not light. My boxes are plastic, not very heavy. I have full length PVC running boards to step on to keep feet off the tubes, that adds some heft too. I wish my boat was lighter, but I sure do like it.
  9. Shapp

    Shapp Active Member

    aluminum pipe cuts easily with carbide tipped chop saw blade. If I was you and wanted that long of a frame sometimes I would have made two seperate modules. One big frame is pretty cumbersome. 2 module setup works just as good and you don't need all of it all of the time. ++ for buying from Jan, action packers flex too much for a rowing seat. Good luck.
  10. isaacfab

    isaacfab Member

    I like the PVC idea. I guess when I made the final decision I knew it was going to be big. I'll keep an eye on extras that will add extra weight. I saw a suggestion to make some sort of wheel so the boat turns into a giant wheel barrow when moving it around land....I'll have to think on that one though.
  11. Ed Call

    Ed Call Mumbling Moderator Staff Member

    Best thing I added was the cooler mount assembly and adding the largest marine cooler I could as my rower's seat. I loved the low back seat (and should build a day trip module with that seat like Shapp suggests about flexibility of modules) but the cooler has really surprised me for its comfort and benefit of great cold storage.
  12. Shapp

    Shapp Active Member

    These are the best low cost rigid plastic "dry box" type I have ever found. Coleman used to sell these. They carry them at storables. I have also seen them sporadically at fred meyers. I got a few about 5 years ago for $20 each and I would probably pay $40 each. I have used them to sit on rowing and they are extremely ridgid and do not flex. The lid has a plastic latice reinforcement underneath and it is totally solid for 200+ pounds of man meat. They even have a rubber gasket. To fit lower in a frame you have to take an angle grinder with cutting disk and trim of a bit of the little "wing piecies under the outside of each corner. Not sure why they are there, but they are easy to get rid of.

    One is under the front seat in this pic:
  13. Ed Call

    Ed Call Mumbling Moderator Staff Member

    These fit my narrow frame very well. For your frame, which is wider than mine, maybe there is a bigger version. Reinforced lid, I can stand on them and I weigh 225. I bought three so that I'd have three lids. One lid in back has a single seat. One lid up front has a single seat. Spare lid for the front can be swapped out so my two little fishy chicks can sit side by side. Lots of storage, not a lot of cost, way better than my first foolish attempt at seats, which were mounted directly to cross rails. No problem with seating on cross rails...problem was absolute lack of storage.
  14. veilside180sx

    veilside180sx Member

    I would've purchased the aluminum fittings, they are considerably lighter than the galvi fittings. It might not sound like much on paper, but every little bit of weight adds up on these.
  15. Shapp

    Shapp Active Member

    Couple more important considerations:

    Looks like you are having a lot of fun which is the important thing! but you will for sure learn a lot about what you don't like as soon as you take your first trip down the river. Fully loaded your floor should at least be a few inches above the water surface. If not, you need longer and/or wider diameter tubes less drop on your bottom side rails, or a smaller frame. My gut reaction is you got too much frame and maybe too much drop for those 16’ long and 22.5” diameter tubes moderately loaded full. Most 16' cats are in the 24+ inch diamter. The extra 2 inches makes a huge difference in bouancy. I hope that I am wrong though. I would also highly recommend pinning the front and rear corner fitting with bolts all the way through the fitting. If your fittings aren’t long enough to allow this, you need to get some different corner fittings. Rowframe has some good ones, as well as Star Inflatables at a reasonable (way less than NRS) price.

    The pics below are of a 14' cat, but the objective is the same, you want the floor well off the water about this much when fully loaded.
  16. isaacfab

    isaacfab Member


    Thanks for the input. I'm going to be working on it tomorrow so maybe I can address some of these issues then. I think that the corner fittings I have should be okay for pinning all the way through but I'll double check. Just to be clear your talking about the top section of the frame and not the floor right?
  17. Shapp

    Shapp Active Member

    YEs the top corners, it also doesn't hurt to do the bottom rail corners, but not as important, although I would on a cat frame that big just to make sure it all holds together. If you are ever in a pin situation, run into a big boulder, etc. water is pretty powerful and you don't want that thing falling appart.
  18. isaacfab

    isaacfab Member

  19. matalpa

    matalpa Member

    I have rented 4 or 5 catarafts, then bought my own 6 years ago. It was nice seeing different designs and figuring out what would work best for us.

    I think there are basically 2 ways to go- minimum weight or maximum comfort/fishability. The light type of boats usually have a mesh floor. I found out pretty quickly that I despise mesh floors. You can walk on them, but not very well. You certainly would not want to stand on them and cast all day. Perhaps most annoyingly, everything you put on them will be soaked if there is anything more than a riffle-no matter how high they sit. Get lots of dry bags. Plus, there is usually enough room for stuff to fall into the water along the edges.

    I think that if a person goes with mesh floors you need to put in really comfortable seats that are positioned well. People will have to stay seated while casting. Having a tube under their feet while seated really helps.

    I put 1/2" plywood floors in my boat. I painted them and put some anti-skid on the tops so they don't get slippery. I think the floor is about 12' long. There is only one bar that you have to walk over to get from front to back, and that is the one with the rowers seat. I also put cargo extensions on the front and back. They add about 2 feet each, and I hard decked and put a casting brace on them for casting platforms. They are great to cast from, but are not so great for landing fish- a long handled soft net is a big help.

    The cargo extensions are great for people to sit on while going down the river. They get used like a tailgate- people sit on them, make lunch there, sort gear, etc. They are probably my favorite thing about the boat. I wouldn't let people sit there in real whitewater, but for trout rivers they work well. The boat fits 5 easily, 9 if you can stand to row it that heavy. It still only fishes 2 unless you want to short-line nymph.

    I haul it with a flatbed/snowmachine trailer, and can slide it on myself, but it is more fun to have help. Last year I bought a winch/roller on a stanchion and that makes it easy, especially at really steep ramps. A few times we have carried it a 20 or 30 yards- it needs 4 guys. I think I could do it with just one other (strong) guy, but there is not a middle lift handle to keep it balanced. I think it probably weighs 400 pounds just tubes, frame, plywood, seats.

    A couple things I have noticed about your frame-

    Are there foot pegs or a tube for the rower to brace his feet against?

    That action packer lid seems pretty slick, might be annoying over the course of a day. When the rafters use a cooler for a seat they often glue foam rubber on top for comfort and grip.

    There are an awful lot of tubes going across the top of the frame- that will be annoying if anyone wants to move around.

    Catarafts do not anchor well, even with a 35 pound anchor. In a foot of water with little current and no one in the boat it works fine, and it beats hauling the boat up on shore, but in much current it does not work. If the anchor holds, the boat walks back and forth, no matter where the anchor line comes off the stern. Usually the anchor just does not hold. Drift boats can anchor in much much more current than cats.

    I can't tell from the pics how heavy-duty the tubes and fittings are. Sounds like you have a plan w/ jb weld- I think that's a good idea.

    Good luck with your raft!

  20. Ed Call

    Ed Call Mumbling Moderator Staff Member

    Matalpa, hoping you'll post some pictures of your cataraft!