Sunday, December 16, 2018

Ladder Molded into Hull

There has been some good discussion and suggestions on the toe pockets that I molded into the hull to serve as a ladder for getting to and from the tender.

Toe pockets forming a ladder to access tender from foredeck

For reference, the pockets are 10" wide and 4" high.  At least that's what the drawing shows.  I haven't actually measured them.  And the depth is unknown.  I asked for them to be as deep as possible without interfering with the interior.  My guess is that they are around 4" deep, maybe 6".

The discussion has been around grab bars so you have something to hold onto while climbing up and down.  This is particularly important because the hull curves inward a bit as you descend.

The picture below shows the most viable options so far.  Note that the distance shown by the red arrow from the lowest pocket to the highest possible grab bar location is 5' 3", so not a huge stretch.

Grab bar alternatives
The default solution is one or two grab bars as show in green, mounted to the surface of the hull, roughly midway between pockets.  I don't think more than two will be needed, and one might even work.

But I'm thinking it would be great if there were a grab bar inside the pocket at the back as shown in red.  Then you would reach into the pocket and grab the bar, just like you would grab the rung on a ladder.   I think that's where there is most likely to be enough space inside the pocket.  But I'm not super optimistic that there will be room.  I just don't know how deep the pockets are, and whether there would be enough of a toe hold if there were a grab bar back in there.  But it would be great to get the grab bars tucked away.

A grab bar could conceptually be attached to the upper inside surface of the pocket, hanging from the ceiling, so to speak.  But I'm pretty sure they would interfere with using the pocket as a toe hold.

17 comments:

  1. I know you are pretty far along with this implementation. Have you considered making a mockup and trying this? Maybe some 1 1/4" plywood, cut the holes, maybe use some large handles you could get a home depot?

    This just doesn't look safe to me, for a 60 something, tired, wet, guy. I think I'd rather take my chances riding up/down in the tender itself! (I have a wireless remote for my davit.)

    Just a thought.

    ReplyDelete
    Replies
    1. I hope not, but time will tell. This is an experiment, and might fail, though of course I hope not. I figure it can't me much worse than the ladder normally used. Riding up and down with the tender is an option, and some people do it, but it's generally consider to be the least safe option.

      Delete
  2. Peter
    At the very least you will have to apply some non skid material such as SiC anti slip tread strips with PSA (Pressure Sensitive Adhesive) to the bottom of each pocket

    Rod Sumner

    ReplyDelete
    Replies
    1. There will be non-skid molded into the tread surface.

      Delete
  3. Peter -- I will defer to you and others about safety and seamanship, but as a climbing guide, I have a couple of points I think you should consider.

    The hull mounted option: The bars will have to stick out far enough from the hull for you to easily grab them while tired, in a swell, with wet hands, etc. In addition, the actual piece of the assembly you grab (the horizontal bar) has to be of sufficient diameter to get a good grip with wet hands possibly wearing gloves. I think such a handle / grab bar will stick out far enough to be a real danger to your shins as you climb the "ladder," especially if there is any type of swell.

    The inside the pocket option: If the pocket is actually six inches deep and four inches vertically, I would be concerned about a grab bar mounted in the back of the pocket. It will have to be near the back to leave room for your foot, and that could place your hand in an awkward position if your bottom foot slips. The good news is that you might might not fall into the water; the bad news is that you might be hanging from your broken wrist. If the bar is not too deep in the pocket, there is less danger of trapping your hand in an accidental dismount, but it might not leave room for a good foothold. Some testing is probably in order.

    Another idea: Imagine two vertical bars mounted near the curved edges at the outside of the pocket and only as deep into the pocket as necessary to ensure they were bedded securely. The concept avoids the issues above, but a man's hand in a glove may not fit on a four-inch bar. However, if you slanted those bars towards the center of the pocket at the top (while keeping them as close to the mouth of the pocket as possible) and left them outboard at the bottom, you might be able to get a six to seven inch bar with room for a good size boot. You would be left with a trapezoid shape for your food ten inches on the bottom and five or so inches on the top and two slightly angled six-inch bars to grab. I am not where I can check the geometry, but it might be worth a look.

    Best wishes, Les

    ReplyDelete
  4. What about two vertical bars, the length of the steps, out board of the steps?

    When we ascend, descend a home ladder, we generally grasp the vertical sides of the ladder.

    That way you are always sliding your hands up and down. You are never out of contact while reaching for the next one.

    I suppose if you lost both foot holds on a descent or ascent it would make hanging on harder than if the bars are horizontal. Although Les makes a good point about breaking your wrist if the bars are inset.

    ReplyDelete
  5. Les, you being a climbing instructor. Is there a practical way Peter could belay himself?

    ReplyDelete
    Replies
    1. Could he self-belay - Yes. But that would have to be done from the deck, so I do not see how it could be done unless he gets off the dinghy at the stern, goes forward to rig the belay, goes back to the dinghy, and comes along side. Or he rigs the belay before leaving. But leaving a belay unattended for any period of time goes against my climbing guide sensibilities. :)

      Delete
  6. Yes, great comment from Les. I'm embarrassed to say that both my daughter and her significant-other are climbing instructors too, including designing and setting routes, and it never occurred to me to ask them :-(. I know they would just magically levitate, but that doesn't work (as if it ever did) for me.

    Vertical bars on either side are a definite possibility too. My thinking has been that vertical bars would be visually more intrusive, but you never know. I'm trying to keep it as stealthy as practical, and at some point it will just look like I bolted a ladder to the side of the boat.

    ReplyDelete
    Replies
    1. Peter -- I thought you might be trying to avoid the "ladder bolted to the boat" look, which was why I was trying to get the bars inside the pockets, but in a manner your hand would easily release if necessary.

      I think it would be worth speaking to your daughter and "sorta son-in-law." I am not sure your hand would catch if the bar was in the back of the pocket; I just thought it was worth considering. A bit of testing with a mock-up, or just seeing how your hand fits in the pocket may put the issue to bed.

      If the pockets were not already formed, you might have been able to mold in a "finger grove", but I suspect it might be too late now. And I do not know if it is even practical to fabricate.

      Best of luck, Les

      Delete
    2. What if you leave the pockets as is and simply have to removable bars that attach to the railings for and gravity against the lower section? Only brought out when in use and therefore no cosmetic issue or space issues as they could be smaller diameter and even two pieces (left and right). Easier to manage that the full ladder per normal but also no issues reducing pocket space for feet. Full vertical sliding hands up and down per the normal ladder too. Just not permanently mounted as you are trying to achieve.

      Delete
  7. why not put a pocket within the pocket, ie: create a grab bar out of the lower leading edge of the step with a pocket for your knuckles. Or, if the opening is 4", make the pocket 2" deeper after, say, an inch of hull, and put a grab bar at the 4" height. So you'll be stepping on the horizontal cross section of hull and the grab bar.

    ReplyDelete
    Replies
    1. Good idea, but too late. It's molded, so I have to work with what I have. But that's a good idea for the next time. The only consideration that comes to mind is that it's important that any pockets be self draining. They will be subject to water coming from all possible angles, and you don't want any pooling.

      Delete
  8. Congrats on the new boat build and innovative improvements. I was wondering, have you ever done a post on what tools you carry on board given your comfort level doing almost all engine work yourself? Also, any improvements planned in that department for the 68?

    ReplyDelete
  9. Hello Peter and thank you for sharing insights and knowledge and writing about your great adventures, lessons learned, and plans going forward. Is the plan to continue this with the delivery of the new boat.

    ReplyDelete
  10. Any updates on this or is covid putting a damper on things?

    ReplyDelete
    Replies
    1. I'm badly overdue for an update.... starting it now.....

      Covid actually has had no impact on the yard and their work. The only impact is that I have not been able to visit, and am not sure if I will be able to before the boat is complete. So we have gotten really good at sending pictures, markups, CAD drawings, etc. I think we are doing pretty well, but won't really know for sure until I see the boat first hand and see everything I missing in the pictures and drawings.

      Delete

Make comments here