Bottom mast cap

njzangle

New Member
Hi everyone,
I just bought a 2000 vanguard Sunfish. It came without the bottom mast cap. The one I ordered from Intensity does not seem to fit?
The OD if the cap is 2.1125" and ID of the mast is 2.0385. Any thought on making the cap smaller or trying to jam it in??
The mast is not out of round - the cap fist perfectly it is just too big.
Thanks Andy
 
Beldar is correct as usual. These new end caps are a bit oversized. Just take a wood file and file down the plastic a little. Then smear silicon goop (technical term) on the inside of the mast and tap the cap in with a hammer. Then you can use the little stainless pins to hold the cap in place or use two poprivets with more goop in the holes when the rivet shaft has popped off. You want a good watertight fit when done.

One more comment. I your boat came with the mast that had no end cap, check the bottom of the mast hole to see if the rotating mast end damaged the bottom of the mast hole cookie cutter fashion. If there is no obvious damage, fill the mast hole with water right to deck level and see if the water leaks out.
If so, you have a leak in the mast hole, probably at the bottom (see how low the water goes.) If you have a leak there, it can be easily repaired with a generous coat of thickened epoxy.

Alan Glos
Cazenovia, NY
 
I had to do this "fix" for a new mast base cap a few years ago - it was a major pain.

I’m not sure if it was because of the age of my Sunfish, or if the mast has experienced some damage at the base after years of use (and abuse?), but it did not come with a mast base cap, and the new one I bought would not fit at all. it almost seemed like maybe the base was necked down just slightly at the base causing the too tight fit. I spent several random nights using a utility knife to slowly whittle small pieces of plastic off around the perimeter of the base cap, occasionally using sandpaper as well to smooth it out some. finally, on the last day, I dug out a rough wood rasp, and that seemed to shave off pieces a little more easily and I could shape it a little better. I also used a curved metal rasp to smooth out the inside of the mast base. after all of that, I was finally able to get the mast base cap into the Sunfish mast.
 
It's possible that your mast base had damage.

Does it measure a full ten feet? Any small section cut from it could account for an inwards taper that resisted seating the plastic bottom cap. The culprit could have been a conventional pipe cutter.

In normal use, the cutter's wheel will depress metal inwards on both ends. When pipe is properly cut with a band-saw, chop-saw, or "cold saw", the cut will be "square", and not smaller internally. The bottom cap would tap in readily.

While it's too late to undo your recent hand-fitting, cutting off just ⅕" from the pipe would've restored the correct internal dimension.
 
This is a problem with how the mast caps being produced not your mast. Here is a cap that I recently took off a brand new mast directly from LP/Selden. Clearly the manufacture (Selden) is having the same issue with there own parts. I have brought this up to both LP and Selden many times since last summer but the results are still the same.

LowerMastCap.jpg
 
Could it have been designed to insert with a 2x4 and a hammer? :(

(And stay put?) :confused:
 
Smear a sealer inside the mast.

Center a loose 5/8" socket over the middle, and give it a whack? :eek:
 
Could it have been designed to insert with a 2x4 and a hammer? :(

(And stay put?) :confused:

It for sure requires a 2x4 and a hammer. It should be as such that it just needs to be tapped in. The problem is with the current part it won't stay in place on it's own without shaving it down as shown in my picture above. All the hammering in the world won't get it in.
 
Here's the type of pipe cutter we shouldn't use on Sunfish spars or masts: It crushes the end being cut, making the insertion of our various Sunfish plastic plugs a problem.

Fullscreen capture 6182021 74757 PM.bmp.jpg
 
I recommend drilling a hole in the middle of the bottom cap of the mast to allow water to run out after sailing. While silicone and other things may seal the bottom for a period of time eventually it will leak and you need some way to get rid of the water.
 
There was a post about this recently. You will need to shave down the cap to fit.

Yes I posted about it in March:

cmac233 took his off his brand new boat and it looked like even the boat manufacturer had to shave it down to force it in. Sounds like there's one manufacturer of the cap and they make only one big run of parts very rarely so we have to make our way through the bad parts before they fix their tooling and make another run.
 
It for sure requires a 2x4 and a hammer. It should be as such that it just needs to be tapped in. The problem is with the current part it won't stay in place on it's own without shaving it down as shown in my picture above. All the hammering in the world won't get it in.
I've already bought my mast plugs from eBay, so I'm not able to test these plugs presently. I would be SO tempted to position the mast over the plug and whack the other end of the mast. (Say, over the side of a flight of stairs). Use a 4-pound hammer and 2x4 to protect the aluminum.

Let the sharp edges of the mast become a "cookie cutter" on the plug. (If it needs cutting at all). Say, I'll need one in about six months. :oops:

Anyone got one for sale? :)
 
Hi
Thanks for the help - I would up using a router to trim the part.
I took a very small amount off each pass with the router speed set to low.
I had started with sanding it but the progress was slow.

Andy
 

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