wooden keel sib?

[Gazzdid]

Hi All
Im sure most of you have seen my previous 'help with project' post, but I thought I would but a separate one out asking if anyone out there has a sib with a wooden 2 piece keel that goes in before placing the floor boards in. I am hoping to get some measurements so I can build a replacement for my boat.

The previous owner had a bonfire and a friend of his mistakenly threw both halves of the keel on the bonfire and burned quite a bit of both pieces away before it was noticed and rescued. a basically have the middle but am looking at the measurements at the ends.

Ive had a look at measuring the depth with the boards in place, as suggested on previous post but im not sure how much tension was on the bottom and what shape it should be.

Its a 3M sib, but I would like to hear from anyone with a wooden keel piece

thanks
Gazz

[blootac]

Hi Gazz
I think I remember your post on rib.net and I suggested not bothering to replace the wood and replacing it with an inflatable sausage keel instead as it would be a lot lighter and easier.
Did this not work? Is there a specific reason you want to replace it like for like?

[Gazzdid]

Yes thats right i did mention this on ribs.net a while ago and it was mentioned to use an inflatable keel. The main problem i have with this is that the floor panels arent used to stretch out the boat like on most sibs, the two piece wooden keel would apply the pressure from bow to transom and stretch the boat out. Then the boards would drop in place. I tried using the boards for this and lets just say they didn't appreciate it! No matter how careful i was and what angles i used they were only going to go down with a crunch! (I needed to get them down so i could take a measurement for the total length of the keel).
Also to use an inflatable keel i would need to remove the brackets that the wooden keel sat in (not sure if this would damage the floor), and drill a hole in a board for inflation. I decided to have a go at making up another wooden keel before i go to these measures. I reposted about it on the off chance there is someone with one that can give me measurements to save some messing around & time.

If this fails i think i will go with the inflatable idea.

Out of interest is there any reason why I shouldn't use the boat as it is, without the keel piece in at all? Going on holiday in a few weeks and was planning on using it. If im not sorted by then I might just use it as-is providing its safe etc to do so. I will only be pootling around a bay inshore with a seagull engine

[blootac]

Oh ok, fair enough.
If you use it without the keel you may find it harder to go in a straight line, you'll slap waves slightly more and if it's used to stretch the boat out like you say then the boards might possibly pop out as you go over swell?
Just my thoughts.

[Martin]

I wouldn't be using it to be honest.
If the keel isn't installed, and I'm correct in my way of thinking, the boats hull will ripple and create a nightmare to keep straight. You certainly wont get on the plane and the drag will be horrific.
From the way you've described the boat, the keel is the main support to keep the boat tensioned, I can't in all honesty see an air keel doing the job either.

Can you post pictures up of the boat and keel? or remainders of what you have?

I take it from what your saying, the Keel was formally wood, was it round or shaped ?
Was it of a bulbous design, ie: thicker and thinner in parts to push the hull into it's "V"

Am I right in saying, you inflated the tubes slightly, install the keel to expand from bow to transom, then when you fit the floor, it pushes the keel down to form the "V" and then the floor sections hold the keel down in place. Obviously then a full inflation on the floaters ?

Sorry if I sound harsh, I'm just thinking you may be throwing time and money at something that may not meet your needs when done.
As a project, I'm sure it'll be a fun thing to do, but for everyday use, I think I'd be looking for something a bit more capable.
Did you not mention that maybe you could do with something a little bigger anyway ?

Again, not trying to put you off what your doing, just trying to save you some possible grief

Martin

[blootac]

I'm with Martin.
I hate to say it but it sounds like it could be a money pit.
If you use it as is at best it'll be a nightmare to steer and slow and at worst dangerous.

Personally I'd chuck it on ebay and let someone else spend the time and money fixing it while I went out and bought something that I could use right away! But that's just me and I'm lazy.

You can pick up 2nd hand sib's really quite cheaply if you look around.

[blootac]

Of course if you want to fix the one you've got we'll all try and help as much as we can

[Martin]

Of course if you want to fix the one you've got we'll all try and help as much as we can

Yup agreed, not trying to put you off, and if we can help, we certainly will... sorry if I came across wrongly.

[Paul]

Gazz

Anything is 'fixable' if you've the time, tools and know how
From my understanding you're left with two halves with the 'knuckle' joint in the middle with the ends burnt away
As you push down the two halves it tensions the keel with the floor slats holding it in place then the inflated tubes in turn hold the slats in place.
If you inflate, measure the overall length required then you could cut off the damaged portions, dowel a new glued timber to the cut originals into place to fit the 'receivers' located at the transom and bow.
You could 'over cut' the added timber to test and shorten them as necessary until it reaches the desired tension fore and aft with the floor slats being level.
Photos would be a great help for us all to assist you with a possible solution as I've got a picture of it in my head and it's not easy to explain in written form

Paul

[Gazzdid]

thanks for the replies and advice. Its a definite no-no for using it as-is then!

Yes the original keel is/was wood. 1" thick ply, and the depth is shaped to give the hull its V. it is shallower at the transom end and deeper at the bow end as expected.

you are both sort of right Martin & paul when you describe how it goes together, but the boards dont really hold the keel down as such. there was a 'nib' on the end that fits into a slot in a fixed wooden panel at the bow (this panel cant be removed) and the other half then fits into position at the transom. there is a sort of S shape or knuckle joint as paul mentioned, at the join which allows you to put the two pieces together and push down, this tensions the boat. there is then a wooden block and bolts that secure the join, making it basically one piece. sounds complicated but its actually easy. the bolts have a shaped end to allow them to easily be turned by hand (no tools required). the keel is now in place and can not go anywhere, then the floor is placed in before the tubes are inflated

I will get pics up asap hopefully it will make sense then

Im happy to take this on as a project as, to be honest, I dont think it will cost much at all (cost of the wood) and I am quite happy and capable of doing the work myself. its a case of figuring out the sizes/dimensions, cutting and shaping. someone I know has said they might even have some inch marine ply i can have, so it might only cost me my time.

I was just wishing on a star someone had one to speed things up but looks like im going to have to get measuring