Porta Boat - Durability & Suitability

[rwidman]

Originally Posted by Canibul

...................... On the rowing flex aspect of it, this is probably a stupid question from someone who doesn't know what he's talking about (me) because he's never seen a PB in person, but would something like a five foot section of PVC pipe across the boat, somehow attached between the oarlocks, stiffen that up somehow? A boathook, cut to length, perhaps?

Just curious. I've been studying the videos and see the flex. And I know what a "blue star pop" is.

Unless things have changed, it comes with a five foot "stick" to hold it open while you insert thee seats. You could just leave it in place.

But why not buy it and try rowing it first before you invent a solution to what may not be a problem?

[Canibul]

Originally Posted by Mike OReilly

Good stuff. I'll be curious to see how you make out, and if you're able to improve things.

Will be a while. I'm not scheduled to be in the US anytime in the next few months. Not til Hurricane season, anyhow. Unless someone suddenly dies, gets married, wins a lottery. You know...those things that can suddenly generate itinerarial recomputations. We were in Cambridge MA for four days in mid winter, totally unplanned. It does happen. But unless I buy a new one, it might be November before I get my greasy mitts on a used one.

you've been rowing one..what do you think? Is the flex all athwartships? Those polypro sheets must have a little longitudinal stiffness. Idea struck me when I saw those people using that notched 2x4 or whatever it is to spread the gunwales. I know the seats stiffen it lower on the sides, but it looks like the oarlocks are unsupported up near the floppy edge part.

[Mike OReilly]

Originally Posted by Canibul

you've been rowing one..what do you think? Is the flex all athwartships? Those polypro sheets must have a little longitudinal stiffness. Idea struck me when I saw those people using that notched 2x4 or whatever it is to spread the gunwales. I know the seats stiffen it lower on the sides, but it looks like the oarlocks are unsupported up near the floppy edge part.

OK, you've got me trying to recall the force vectors and material responses. I'm away from my bote until the water turns soft again. I won't get back at it till late June, otherwise I'd start experimenting. Watching a video of me rowing, it looks like the flex is all in the gunwales centred around the oar locks (no surprise there). I'd say the gunwales flex out, but also slightly down -- almost a rotational effect.

Distributing the force across more the gunwales would likely improve things. A rigid cross-beam member at the gunwale hight might help (rwidman's idea), but that might interfere with getting around in the bote. Not sure... You've got me thinking.

[alctel]

My second hand bote didn't come with the helping stick, is it just a stick or does it have cut outs etc on it? How long is it?

I managed to get mine open solo on the deck of my boat, but it was quite a struggle, I can see how a prop stick would be a big help.

[Mike OReilly]

Originally Posted by alctel

My second hand bote didn't come with the helping stick, is it just a stick or does it have cut outs etc on it? How long is it?

I managed to get mine open solo on the deck of my boat, but it was quite a struggle, I can see how a prop stick would be a big help.

The stick is basically the beam width, with notches to fit over the gunwales. I can't tell you exactly how long it is b/c I long-ago lost mine. I don't think it's needed.

I just use one of the middle seat as the initial brace. My approach is get the brace/seat braced against the gunwale, pushing against the floatation foam. Then I push the bote open and wedge the seat in to keep it open. Doesn't matter where it lands since it's just the brace. I then put in the aft seat, and then go back to the middle seat (wedge) and place it into it's proper bracket.

The brace stick does the same job, but I found it would sometimes slip off the gunwales. In the end, I just found it easier and simpler to use the middle seat.

[Canibul]

My idea was most specifically a rigid crossmember at the gunnel height, at the oarlocks. I was watching the notched stick videos, thinking about boarding over the floppy side, and then saw your comments about the oarlocks flexing under heavy rowing, etc. I have a mental image now of two brackets that slip over the gunwhales and a cross piece that pins into place to stiffen the whole boat up, for those times when you need it. Being able to reach into the boat with one hand and grab that cross piece in the middle might help boarding over the side. I know it can help to grab a thwart in the middle of a canoe to board, for example. Similar issues here.

I figure someone with access to a porta-bote will be trying this before I can get one. And here it is sunny today, 81 deg.F. 8 knots of wind at the moment...

[ejlindahl]

I noticed the flexing was more pronounced on a hot day. Rare for Seattle but always hot in the Caribbean.

I made a longitudinal stiffener out of a ~ 1" x ~2" aluminum box beam with a largish notch in the center for the oarlock. The beam was actually a stile from my salvaged sliding glass door frame. Its about 2' long and goes on the inboard side just under the black ~1" "pex pipe" stiffener that goes all the way around the boat. I had to cut out a little bit of the black flotation foam to make room for it. This longitudinal stiffener is centered on the oar lock. I don't have access to the bote right now and I forget the details but it sounds like you are capable of figuring out something along these lines if you want. I think it helps reduce the flex a bit but also spreads out the "point loading" or "point flexing" that occurs right at the metal oarlock. On hotter days this was a bit alarming to me but maybe its not a big deal. Their structural reputation and durability seems very good.

I think your idea of an athwartship stiffener may help as well. Obviously you will have to step over it to move about the boat. It probably ought to be securely fastened to the gunnels on each side as the flexing in and out will easily dislodge a simple "stick" wedged between the gunnels. But I would use a movable temporary stiffener to figure out exactly where the best place would be to place the final attachment points.

I find the hold open stick to be very helpful when assembling the bote. If I lost mine I would make another. Its actual dimensions are about 1" x 3", (not a 1x3 which is actually in the USA 3/4" x 2.5"). Its hardwood and with the thicker dimension both help to stiffen the board. An old growth tight grain fir 1" x 3" might be stiff enough, though. Stiffness in the board is important because there is significant tension force on the long board, especially in colder weather, that could cause a typical lumber yard, knotty, soft wood 1x3" to flex or break. A 1x3 or 1x4 is cheap though so you could try it and see if it works. I don't know how long the board is or how far apart the notches are but the website or Yahoo portabote group will have that info.

There are three notches in the board. One on each end and a third about a foot back from one end. The "set back notch" opens the boat a little less than needed. However, its easier to open it to this stage initially because the boat can be pretty stiff to open up, again, especially in cool weather. Then you reposition your hands and push the board further to open the boat the last foot. Whereupon you set the notches at each end of the board into the ~1" pex pipe "cap rail" the sits atop the gunnel. I suppose on the website or Yahoo group there are dimensions and good pictures of the board if you need to make your own.

[rwidman]

Originally Posted by alctel

My second hand bote didn't come with the helping stick, is it just a stick or does it have cut outs etc on it? How long is it?

I managed to get mine open solo on the deck of my boat, but it was quite a struggle, I can see how a prop stick would be a big help.

Set your boat up, then take a piece of 1" by 2" wood and cut it to the width of the boat at the widest part. Cut a semi circle in each end to match the round trim and you have your stick. The original has a notch a foot or so from one end, I suppose to prop it part way open and then get a better grip to open it all the way. The boat will be harder to open when new and harder to open when cold.

[ctl411]

My 14 foot came with square tube along the sides.
Big improvement or our 12 foot individual seat mounts. Not sure if this was a "year" upgrade or size related.

[jwcolby54]

I am looking at a used 8' with a 4 HP engine. The 4HP is over weight for the 8' boat (55 lbs), not sure why the owner bought that. Will this be a problem? I can sell that engine and drop down to a 2hp I suppose.

I have a 33' and single hand it. I am trying to figure out how to get the motor off and the PB up on deck quickly and easily. I am ok with installing something like the NovaLift or similar crane. Or even dinghy davits on the back of the boats.

So my questions are:

1) when in port, can I just lift the PB with motor attached on a three point (bow / aft) rope / cable rig? I assume so on dingy davits. How about on a crane?

1a) Cranes don't seem to have much horizontal reach. Can they in fact lift a PB (with or without motor still attached) without banging the hull.

1b) Can they swing the PB over the lifelines?

2) How difficult is it to get the motor disconnected and up on deck using a crane or a block and winch.

2a) Difficulty getting a 55 lb motor up on some kind of mount and locked down?

2b) How do you lock down a motor to prevent theft?

3) Has anyone used the boom to do this (lifting / moving the motor)?

4) Difficulty getting it into the water once assembled.

5) If just hung in port, at night, what it the probability of theft.

6) if using a crane, is a crane at the back or the side better? If at the back, the motor is easier. At the side, getting the PB on deck is easier.


Please remember "single handed" which I will almost certainly be most of the time.

It seems like leaving the whole thing assembled with motor in place while in port is the only solution so a "hanging" method (that won't promote theft) is desired.

Sorry about all of the questions all at once, but this is a pretty complicated interconnected set of decisions to get a solution that works.

[alctel]

I yank mine up by the bow using a halyard, and then shove it over the lifelines. Not too subtle.

[ctl411]

You can use the boom to lift boat and motor.

[jwcolby54]

Originally Posted by alctel

I yank mine up by the bow using a halyard, and then shove it over the lifelines. Not too subtle.

Not with motor attached I assume?

[Stu Jackson]

jwc,

Cranes: Garhauer has great motor lifts, They also have two different lengths for the booms, so you need to simply measure carefully.

55# motor would require a pad on the pushpit to mount it. There are wooden ones, metal ones from Edson (a tad expensive!!!) and you can make your own from wood or starboard.

One of our skippers suggested buying two Garhauer motor lifts and using them as a "poor man's" davits. If you're not going to go sailing with the dinghy hanging off the back, that is something to consider. It would be a lot less expensive than davits, which are a "push" on a 33 foot boat anyway.

As far as PB boats go, these guys have lots of experience with one: The Internet while traveling | Sundowner Sails Again They show up here from time to time, too.

Good luck.

[alctel]

Originally Posted by jwcolby54

Not with motor attached I assume?

Hah, no. I actually row almost everywhere - mine came with proper wooden oars and modified oar locks.

I got a free 6 HP outboard but I haven't even tried to start it yet.