Scamp 527 - Mast Box Ramp?

The place to discuss SCAMP (Small Craft Advisor Magazine Project), our 11' 11" micro minicruiser.

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max
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Scamp 527 - Mast Box Ramp?

Post by max »

Hey all,

I'm building 527 here in Seattle from a kit (that's actually about three years old - it's been sitting in my garage for a while before I finally started in on it). I'm at the point where I'm dry fitting the stem and bulkheads 3/2/1, and I can't quite figure out some things with the mast box.

First of all, I *think* the sides of the mast box are supposed to rest on the flat bottom of the mast box (which in turn rests on the stem), however as I dry fit everything together I don't have enough space there for a 9mm piece of plywood.

Image
Image

I do have a lip at the very top of the forward mast trunk piece though, as the routed groove for where the mast trunk sides fit in doesn't go all the way to the top.

Image

I'm going to guess that the lip there is really an artifact of CNC cutting for some reason and that if I remove it and have the sides of the mast trunk end flush with the top of the forward section of the mast trunk, that I'll have enough space at the bottom for the mast trunk floor?

Secondly, I've heard of a "mast ramp" or "Scamp ramp", it's mentioned in a couple of threads here, but I can't find any reference to it in the plans or the build manual (version 1.5), and I don't think i have any pieces unaccounted for from the kit. Are there details somewhere of the ramp? Is it just a simple square piece that fits between the mast trunk sides aft of bulkhead 3 and the end sits on top of bulkhead 3? Or maybe the end butts up against bulkhead 3 and it's wide enough to span the masthead sides and attaches underneath them?

Image

Thanks all!
phatguppy
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Re: Scamp 527 - Mast Box Ramp?

Post by phatguppy »

The mast trunk floor is a small piece in the CNC kit that fits that area, its easy to miss. Check sheet 7 in the plans if you cant find the piece.
max
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Re: Scamp 527 - Mast Box Ramp?

Post by max »

The mast trunk floor I found in the plans, and that fits beautifully just above the stem at the bottom of the mast trunk. But I can't find any reference to the scamp ramp itself in the plans or the build manual.

Looking at it some more, I decided to remove the little lip on the top of the forward piece of the mast box, as it's not there in the plans and it does seem like everything lines up well without it. The scamp ramp itself, from staring at a couple of other folks' build photos (and zooming in way too much) it looks like the ramp is attached to the bottom of the mast box side pieces extending aft of bulkhead three. What I can't tell from those other photos is how it rests against bulkhead 3 - do the mast box side pieces rest on top of 3 (like in the photo above) and the end of the ramp is beveled to rest flat against the front face of bulkhead 3?
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jfhbc
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Re: Scamp 527 - Mast Box Ramp?

Post by jfhbc »

For the ramp, I brad-ed + epoxied the rectangular ramp piece to the bottom of the mast box sloped extensions (the bits that go aft into a point). I bevelled the forward part of the ramp at the correct angle to mate vertically against the outside of the aft part of the mast box. Filleted and glassed the top of the ramp, making sure to rise up the glass a bit on those curved fillets to reinforce the ramp joint, and also to reach down into the mast box.

The part that sees the most stress, from the way I step the mast at least, is the top forward part of the ramp, at the angle where it meets the mast box. When the mast is being unstepped, I "lean" the mast back at about a 45˚ angle, with the base of the mast pressing against the forward part of the box and the mast body briefly resting on that joint. This takes the weight of the mast for a second while I re-align my grip further back and finish extracting the mast.

All this to say, I'd recommend making sure that top-fore joint in particular is well glassed. All other parts of the ramp rarely see much stress.
Jean-François
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max
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Re: Scamp 527 - Mast Box Ramp?

Post by max »

Thanks Jean-Francois, I think that gives me all the info I need to figure out how to put it together!

Now to drill out the bushing on one side of my centerboard case, as I just discovered when I glued that in last night it wasn't in perfect alignment. Grrrr... ;)
GregWads
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Re: Scamp 527 - Mast Box Ramp?

Post by GregWads »

I used a foot long piece of stainless that eventually was used to create the centerboard pin to hold the bushings in alignment until the glue set.
max
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Re: Scamp 527 - Mast Box Ramp?

Post by max »

I thought about that GregWads, and I might still try it for the re-glue, but the worry I have is that a little bit of epoxy gets pushed out of the hole as i push the bushing in, and gets caught between the bushing and the stainless pin, thus gluing that into the bushing! I'm not sure how to prevent that from happening, given the clearance between the bushing and the pin is so tight.

I'm currently thinking perhaps the way to go is to use a flanged sleeve bushing - that'll make sure at least the epoxy doesn't get pushed out close to where the stainless pin is inserted into the bushing itself...
GregWads
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Re: Scamp 527 - Mast Box Ramp?

Post by GregWads »

Yes the epoxy did get on the pin and bushings, but luckly I had lightly waxed the pin and the inside of the bushings. The cured epoxy just cracked off the protected surfaces.
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