Access all areas – or not?

[Peter CrowParticipant @petercrow25030]

[Peter CrowParticipant @petercrow25030]

 

The build of my RG65 progresses and I have reached the stage of cutting out LitePly for the deck. I find this to be a daunting stage. The boat's internals are going to be sealed over, some never to see the light of day again.

I'm planning access arrangements to those areas to which access will be required. As I already have a Joysway Orion, I'm familiar with the sticky-backed Dacron fabric patch for covering openings in the deck. I procured some of the aforementioned Dacron in order to cut out replacement patches and find that the metre I bought should keep me in deck patches for the rest of my natural! I am therefore going to follow a similar route with my scratch build.

My experience to date is of building scale or semi-scale electric powered models with a reasonably high freeboard only having to deal with relatively small quantities of water across the decks. A sailing boat in anything other than very light conditions is another matter. I'm building with the thought in mind that the deck could be continually awash with water. In an ideal world I wouldn't have any openings at all!

I have modified the Racing Sparrow design to follow the Jowsway Orion and DF65 practice of having a lowered after deck allowing any water ingress via the rudder tube to flow outboard. The rudder linkage is therefore exposed for adjustment as necessary. The on/off switch will be controlled via a push-rod in this area.

What other access to the interior of the hull is really required?

There is one definite:- the battery, for removal for replacement or charging.

I'm minded to leave it at that and only have the one deck patch. But then part of me says, "What if something fails and needs attention?"

My first instinct was to try and design a clever arrangement that allowed access to all internal components. That would, however, entail either one relatively huge opening in the deck, or several smaller ones. More scope for leakages and the LitePly structure would be considerably weakened

Do I really need this level of access?

My current thinking is to only have an opening for access to the battery. If any other component fails, I can cut out an opening in the deck to effect a repair and cover the said opening with a patch afterwards. (Isn't this the approach of the MOD to major repairs to type 45 destroyers?!)

My heid is birling (as we say here in Scotland). I hope that you guys can help me to straighten out my ideas before I pick up the glue and hide everything away for ever!

 

Edited By Peter Crow on 09/01/2020 23:31:07

[ashley needhamParticipant @ashleyneedham69188]

Peter. Know what you mean about perhaps needing access later on.

I have dealt with this in the past by having a “sacrificial” hatch, i.e a hatch, perhaps of thinner stuff, lightly glued in place. If access is required later on, then a bit of scalpel work can cut the hatch away, do your maintenance and then glue another hatch on.

On my Ecranoplan, the thick tail holds the rudder servo, and a thin card patch was glued on to cover. In practice, you don’t notice it, it is so thin. Perhaps in your case something slightly stronger might be best to retain hull integrity, but if the hole is not too large, 0.8mm ply could be used and would be stiff enough.

Ashley

[Tim CooperParticipant @timcooper90034]

Peter

I have made hatches to cover parts of hulls and sealed them in place with bathroom silicone. It is waterproof and some of them can be painted. Just loosen with a knife to gain access, clean and reseal with fresh sealant.

Tim

[Ray Wood 3Participant @raywood3]

Hi Peter,

You really only need access to replace all the expensive bits and access to replace the lines to your lever winch servo, commercial boats ie Dragon Force 65 & Dragon Flite 95 have relatively small access hatches because they are using drum winches and deck line sheeting with elastic return to keep the line taught. You could have more smaller openings keeping the structural integrity of the deck, remember round corners to any hatch opening are stronger than square ones. I always think of the square Dehavilland Comet square windows which failed So maybe only a small hatch for charging and venting the hull which you will need to access regularly. the other ones taped shut.

PS. Nice looking build

Regards Ray

Edited By Ray Wood 2 on 10/01/2020 11:33:50

[Peter CrowParticipant @petercrow25030]

Thanks chaps for your advice and experiences. They're very useful and I'll be able to better order my thinking.

What I have decided to do in the meantime is to expand an idea that I was working on.

When building the hull, I added 'strongpoints' into which I can screw through-deck fittings. It occurred to me that it might be a bit hit and miss trying to accurately locate them once the deck is in place. I therefore took a roll of baking parchment (in lieu of tracing paper) and carefully pinned some to the hull over the deck aperture. I traced around the structural elements of the hull. This means that I have an accurate picture that I can lay over the deck, almost as an x-ray picture of the skeleton that lies beneath. I'll go further and accurately depict the locations of all the interior fittings so that if I have to do some surgery to the deck at some later stage, I know precisely where to wield the scalpel.

All the best, Peter

[ashley needhamParticipant @ashleyneedham69188]

Peter. Sod’s law No2..the easier it is to access something the more reliable it becomes. The harder it is….

Good idea for the X-Ray diagram.

Ashley

[Colin BishopModerator @colinbishop34627]

Dave Milbourn did tell me the other day that Liteply is prone to delamination if it gets wet so I would ensure that all hidden areas are properly sealed before closing them up.

Colin

[ashley needhamParticipant @ashleyneedham69188]

Hmm…was just off to get some liteply….

[geconParticipant @gecon]

Does liteply have a balsa core? Balsa loves water and needs to be well sealed of course.

Interesting inputs on hatches. I've spent some time recently trying to 'hatch' out some ideas for reducing water ingress on my scratchbuild Fisher. The newly acquired Colin Archer has a large flush-deck-hatch which is bound to be a source for a bath-in-the-bilges.

Regarding bathroom sealant (acrylic based can be painted I think) I wondered if you can line the hatch opening with plastic 'clingfilm' ? Then apply sealant to both hatch and deck frame, lay on a layer of 'clingfilm' and close the hatch! Assuming that the sealant won't stick to the 'clingfilm' ?? then there should be a well-fitting joint there afterwards and -with a bit of luck- a removeable Hatch!

Plumbers use a thin silicon tape to seal the threads on pipejoints. I wonder if this could be used to make a waterproof seal around a hatch? I am assuming that the silcon tape will fill most irregularities in the hatch/deck joint.

I'm very new in the boat-sealing buisness so forgive if I'm miles off target…which often happens when I start thinking…..

[ashley needhamParticipant @ashleyneedham69188]

George. Liteply does have a balsa core, but I would not worry about using it, just splash lots of your chosen waterproofer on it.

Really the only way to have a watertight hatch is to have some sort of fastening holding it down. Magnet, screw or whatever. tHEN if you have decently mated surfaces just a wipe of Vaseline will do to provide a seal.

Ashley

[Ray Wood 3Participant @raywood3]

Hi George,

I owned and sailed/motored a Billings Colin Archer for a couple of seasons, as the standard design they are not performance sailing boats, in a gust the rudder is too small to stop the boat luffing up into wind, and in light conditions you will need the motor to tack, with the amount of ballast in the long keel I never had any water ingress via the deck, they are very popular and pretty craft, but frustrating to sail if you are used the sailing yachts.

Regards Ray

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