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**knottybuoyz** · 12-07-2016, 13:16

Back out in the shed for awhile today to get some stuff done before the heat rises.

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Lined up bulkhead E and prepped it for some quick tabs tomorrow. Today's web log update also includes a Season 6 Premiere Youtube video!

https://she-kon.blogspot.ca/2016/07/the ... blood.html

Standby...

delmarrey · 12-07-2016, 14:05

ya might want to think about your chain locker too, in relation of the windlass position and how much chain you're going to use, with drains and all. Dunno if its in your drawings.

In some tabbing I've seen, around a 1/2" strip of soft core foam is placed between the bulkhead and hull, to absorb flex and bumping. Did that on mine vs the original air gap. I used the white polypropylene, like what is used in packing. It cuts with a bandsaw and is resistant to resins (epoxy).

**knottybuoyz** · 12-07-2016, 14:25

Quote:

Originally Posted by delmarrey

ya might want to think about your chain locker too, in relation of the windlass position and how much chain you're going to use, with drains and all. Dunno if its in your drawings.

In some tabbing I've seen, around a 1/2" strip of soft core foam is placed between the bulkhead and hull, to absorb flex and bumping. Did that on mine vs the original air gap. I used the white polypropylene, like what is used in packing. It cuts with a bandsaw and is resistant to resins (epoxy).

Hey Del

There's not much info on chain locker size on the drawings. It's pretty much backyard eyeball engineering. I think I'm going to 'flush' the foredeck so that'll add an extra 8" which should leave plenty of chainfall. Got the drains in mind as well.

I should ask the designer about an air gap or some other filler for the bulkhead to side join. I know he shows it in his 'foam option' for the boat but not the ply version. I'd be a tad worried about hard spots forming spider cracks. Hmmmm?

Thanks for looking in.

delmarrey · 12-07-2016, 15:01

Yeah, one good bump against a dock next to a solid bulkhead could cause some problems.

Some of the steel ships I've worked on had a "U" welded in right where the bulkhead meets the hull. Or large gaps with just fingers welded to the hull, depending on the application of the compartment.

And that chain fall ratio seems pretty important, especially if one is using rope rode. My boat came without a windlass (racer) so I got lucky with mine. Although, I had to mount it as far aft as I could with that pointy bow and all.
I also had to put in a 6" spurling pipe to keep the chain from slapping the under-deck. As well, you'll want to put in a good sized inspection door down below just in case you get a jam-up (twist in chain), as well as being able to wash down the chain and locker when you want. Some of the gunk-hole muds are pretty stinky and will smell through out the interior.

If the locker is big enough. I've seen mushrooms in the base to keep the chain from kinking.

.

delmarrey · 12-07-2016, 15:05

Better view of mushroom......

.

**knottybuoyz** · 13-07-2016, 02:05

Quote:

Originally Posted by delmarrey

In some tabbing I've seen, around a 1/2" strip of soft core foam is placed between the bulkhead and hull.....

Do you remember how thick the foam was you used Del? I used two stack popsicle sticks when I bedded the stringers, probably 1/8". Thinking the same would be Ok for the bulkheads.

**knottybuoyz** · 13-07-2016, 09:24

Quote:

Originally Posted by delmarrey

In some tabbing I've seen, around a 1/2" strip of soft core foam is placed between the bulkhead and hull, to absorb flex and bumping. Did that on mine vs the original air gap. I used the white polypropylene, like what is used in packing. It cuts with a bandsaw and is resistant to resins (epoxy).

I found some high (not that high but stiff enough) PVC closed cell tape that's 1/8" thick (I'll likely use two layers on the main bulkhead, to isolate it from the hull sides & bottom. Think that'll work.

delmarrey · 13-07-2016, 10:00

I got the idea from a builder on the net. The foam is basically used as a spacer for the bulkhead to hull, and has no real function. And if the hull takes a hit the foam will just crush. I suppose the foam could be removed once one side is taped up, if it'll come out.

I had to put my bulkhead in, in two pieces, port and stb. And wasn't a perfect match due to all the stringers and supports. I had to get them thru the passage ways. But it was 7 to 12 mm gap. The foam wasn't a full wrap. Just long enough strips to support the weight until the tabbing was in place. The site also recommend using a 10 oz. X 3" tape (stitched edges).

**knottybuoyz** · 13-07-2016, 11:54

Hey Del

That's basically how I did the stringers. The gap was about 1/8" on the outboard side and because of the angle of the hull bottom about 1/2" on the inboard side. I didn't fill the entire gap, just filleted as normal and taped. On the stringers I used 8" x 12 oz Biax tape. I'll use that as well on this main bulkhead.

Thanks for putting me on track with that one. Nice catch!

delmarrey · 13-07-2016, 12:30

When in the Navy, out in typhoons, aboard ship I use to watch the stress/exspansion joints. One really gets the drift about allowing the boat to flex. At first it seems scary but you realize the importance of the joints when cresting them big swells. The supper structure at the top would move back and forth as much as 4" apart.

Not so important on composite boats, but welded metals its critical.

**knottybuoyz** · 13-07-2016, 12:56

The icebreaker/buoytenders I worked on were tough. No flex. Built like tanks and then some. They were often counted to enter areas of low water to service aids to nav etc. and it was nothing for us to bump along the bottom or over a shoal. More than once we had a Captain drive up onto the rocks. Scratched some paint and maybe a wee dent in the hull!

https://youtu.be/rHlEXn37dVg

delmarrey · 13-07-2016, 13:11

Love boats like that but the co$t. Use to coxswain a landing craft in Vietnam. Was fun running them up on the beach and backing out.

**knottybuoyz** · 16-07-2016, 03:30

Main bulkhead tabbed in. I'll finish it up today. I left about a 3/16" gap all around so the bulkhead isn't touching the hull.

Updated the web log. There's another video but it's looooooong! I mysteriously turned into a Chatty Cathy for some reason!

https://she-kon.blogspot.ca/2016/07/ordinary-day.html

**knottybuoyz** · 20-07-2016, 11:46

Took a few days off and went on a lil' road trip to Syracuse NY with the Admiral. She was all hot to trot to get into Hobby Lobby and buy buy buy stuff! I went along if I was allowed in Harbor Freight Tools unsupervised and with no limit on my Credit Card!

Part of the haul from HF.

This lil' trip is usually an annual pilgrimage but it's been a few since we last made the drive. I like their stuff. It's 'good 'nuff' to last the duration of my project.

Back in the shed today. Got the forward edge of the main bulkhead filleted and taped (2 layers so far). Gotta check the instructions to see how many are recommended. I'll add at least 1 more 12 oz 8" tape.

And the stbd side.

It was 32C (90F) in the shed but with all the fans going it was actually pretty comfortable. Had to work quick though, I could feel the epoxy warming up quick in the cup!

Back at it again tomorrow.

Cheers!