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Retro-fitting scupper?

Posted: Fri Sep 28, 2012 5:44 pm
by goanywhere
Hi all. I'm getting to the point of doing some maintenance on the Sabalo. I've put it off until the weather has got a bit warmer. One thing I'm thinking of doing is retro-fitting at least one scupper in the rear cockpit area of the Sabalo. Any ideas of how I could do this? I have a hatch cut under the seat so I can access the area inside but it is a bit tight. Could I use a tube of some sort?

Steve.

Re: Retro-fitting scupper?

Posted: Fri Sep 28, 2012 10:12 pm
by JGood
I have added scuppers after the fact. I take a piece of 1 " pvc and place it inside of a piece 2" pvc and pour it with a fillet material made with fumed silica, sawdust and epoxy resin, which makes a tube with about 3/8" walls. When the epoxy mix is set I drive the pipes out of the epoxy and have a scupper tube ready to install. Then I drill through the deck with a 2 1/4" inch forstner bit and through the hull with a 1 1/4" bit. Next, I take sand paper on a stick and rough up around the holes and lay a bed of fillet material around the hull hole and drop the tube into it and fill in the deck hole with more fillet material. It is important to keep every thing properly aligned while the epoxy sets. To cut the tube to the right angles, I hold the tube under the hull and scribe the angles, then measure the length and mark the other end to the angle of the cockpit deck. I make the tubes slightly shorter so the fillet material on the top slopes down from the top of the deck to the scupper tube and squeezes a little under the deck. I have not added any cloth to the bonds and they are holding up quite well. By using pvc to form the scupper tubes, regular scupper plugs can be used to plug the scuppers when they are not needed or extra weight onboard causes them to take on water. I have used these on every boat I have built either as I built or retrofit and they work real nice. I hope I have explained this in away that helps. Good Luck
Jesse

Re: Retro-fitting scupper?

Posted: Sat Sep 29, 2012 4:59 am
by goanywhere
Thanks JGood. That is a good explanation of how to go about it. Just a question, how do you make sure that the inner tube stays centred in the outer tube when you're forming the scupper tube?

Re: Retro-fitting scupper?

Posted: Sat Sep 29, 2012 6:48 am
by PiratePete
I made my scupper tubes by setting up a piece of electrical conduit that I then wrapped a sheet of tuff plastic around.

I set this up on the bench with an old pulley so I could rotate it easily by hand.

Then I made up a batch of resin & coated the plastic sheet & layered up a length of fibre glass cloth as I slowly rotated the pulley making sure I wet the glass out as I went.

Once the resin had set I slipped the conduit out of the plastic sheet & then rolled the sheet up tighter to release it from my fibre glass tube that I could then cut to the required length.

Image

On my second Wadefish I drilled the hull with a hole saw big enough to slide my tube through. For inside the hull I made up a washer of ply that sat around the tube & also gave me a larger surface area to hold the tube in position. I cut the tube longer than I needed by a few millimetres so when it was all glued in position I could sand it back flush to the surface of the hull.

Re: Retro-fitting scupper?

Posted: Sat Sep 29, 2012 10:14 am
by JGood
Steve
To keep the pipes centered I have done it a couple of ways. The best one, since I am also a woodturner, was to turn a plug for either end that had recesses for the different sized pipes. The other is rip strips of wood the size of the gap and cut short pieces to fit between and around the pipes and stick duct tape over the ends. I put the sticks in one end, then fill them with the fillet material and place sticks in the top to hold them aligned. You just have to make the tubes long enough to cut off the ends to eliminate the wood in the ends. I mix my fillet material in a zip lock bag and cut off a small corner to fill the tubes with. I have considered wrapping the smaller pipe with fiberglass cloth before placeing it in the larger pipe, but I was afraid the fillet material would not saturate it properly and there might be voids. Glass fiber fillers would probably be a good idea, even though I haven't had any problems with my mix. A little paste wax on the pvc pipes prior to assembly helps seperating them easier.
Also, when locating the holes in the hull, I drill the deck holes and place the tube in the hole and then take a paddle or forstner bit that fits inside the tube and drilled just enough for the spur to show through the hull. Then I could drill from the bottom up with the larger forstner bit. You get a cleaner hole when you drill this way. By using a bit larger than the interior, yet smaller than the exterior tube size, the exposed wood in the hull is covered by the fillet material and the fillet can be sloped into the hole, making a neat job.
When installing two scuppers that I wanted to use a scupper hole cart with, I made a simple jig with strips of wood that fit inside the tubes to hold them parallel to each other to mark the location for the hull holes. The jig is made by tacking parallel sticks to a cross piece making a squared C or H shape. When I have the tubes in place, I hold them firmly in place while I slip the jig out and then mark the holes with the paddle bit. A couple of extra hands are nice for this, but I normally have to manage it alone. After the tubes are filleted in place I slide the trueing jig back in while the fillet sets up. I make my scupper carts with pvc, also.
Good Luck
Jesse

Re: Retro-fitting scupper?

Posted: Sat Sep 29, 2012 5:40 pm
by goanywhere
Thanks JGood. I will only want one. I assume that to get the bevel at the top you need to insert the tube from the bottom. I can visualise how the tube is filleted in place at the top (Cockpit) by making the hole mid-sized, but how do you fix the tube in place on the hull end so that it is secure? I assume you can glass over the join, is that how you do it?

Re: Retro-fitting scupper?

Posted: Sat Sep 29, 2012 5:53 pm
by goanywhere
PiratePete wrote:I made my scupper tubes by setting up a piece of electrical conduit that I then wrapped a sheet of tuff plastic around.

I set this up on the bench with an old pulley so I could rotate it easily by hand.

Then I made up a batch of resin & coated the plastic sheet & layered up a length of fibre glass cloth as I slowly rotated the pulley making sure I wet the glass out as I went.

Once the resin had set I slipped the conduit out of the plastic sheet & then rolled the sheet up tighter to release it from my fibre glass tube that I could then cut to the required length.

Image

On my second Wadefish I drilled the hull with a hole saw big enough to slide my tube through. For inside the hull I made up a washer of ply that sat around the tube & also gave me a larger surface area to hold the tube in position. I cut the tube longer than I needed by a few millimetres so when it was all glued in position I could sand it back flush to the surface of the hull.
Thanks PiratePete. This is how I was thinking of doing it. I like the pulley idea.

When you are placing the tubes, how do you fix them in place? I assume you fillet them, but how do you do it? I had a good look at my Sabalo yesterday and I think it would be a job to get my hand in there far enough back to apply filleting compound. I was thinking of duct taping that end in place then using a long tube on a syringe and squeezing the fillet around the hole, and then letting gravity flow it into place around the tube. But that will only work for one end, I won't be able to get filleting material on the inside at other end. I was thinking maybe sanding it down flush then glassing over the hole, then after it cures cut out the scupper hole, then tidying it all up after that.

Re: Retro-fitting scupper?

Posted: Sat Sep 29, 2012 5:56 pm
by goanywhere
JGood, I was thinking if you wanted to have a glassed thick walled tube like you were thinking, you could make a tube like PiratePete shows then use that as your inner tube when you make your thick walled one. That way you will have glass on the inside, and you won't have to remove the inner tube when it cures. :wink:

Re: Retro-fitting scupper?

Posted: Sat Sep 29, 2012 6:17 pm
by JGood
Steve I put the large hole in the deck and the midsized hole in the hull and insert the tube from the top. I used a craft stick from underneath to place the fillet on the inside of the hull hole then when the tube is pressed into it I shape the fillet to slope to the hole. I then add fillet from the top of the deck. The tube is cut equal to or slightly lower than the bottom of the deck material. After the fillet is cured I rasp orDremel it to the final shape and add a couple of coats of resin. I have not used any cloth, because a scupper plug will not seal properly in the inside of te tube isn't smooth.

Re: Retro-fitting scupper?

Posted: Sat Sep 29, 2012 7:55 pm
by goanywhere
JGood wrote:Steve I put the large hole in the deck and the midsized hole in the hull and insert the tube from the top. I used a craft stick from underneath to place the fillet on the inside of the hull hole then when the tube is pressed into it I shape the fillet to slope to the hole. I then add fillet from the top of the deck. The tube is cut equal to or slightly lower than the bottom of the deck material. After the fillet is cured I rasp orDremel it to the final shape and add a couple of coats of resin. I have not used any cloth, because a scupper plug will not seal properly in the inside of te tube isn't smooth.
Yes I can picture that. Obviously the tube will have to be held centre on the top (unfilleted) end while the hull end cures. That should be fairly easy with a makeshift jig of some sort. The fillet material will obviously need to be fairly firm so it holds in place and doesn't run, but that's not hard.

I think I have it JGood! I'll give it a go as part of my Spring/ Summer maintenance work. I have to recoat the varnish and seal some hatches a bit better, so this will be just another job.

I won't be able to install the scupper in the centre at the rear of the seat because of the bracing piece under the floor that runs along the centre. I will have to place it on one side, and maybe do another one later on.

Thanks a heap JGood!