I had a nice sheet of 1/2" marine plywood. Now I have a stack of five things. I thought I had a clear idea how to get the mast step done, so I just went for it. I stopped to take a look at the bigger picture after 5 layers. Something does not look right.

Back at the computer I see that my stack of plywood does not look like Arne's mast step. The thing I have is a lot wider and still not as thick. It is so wide that I can't fit the biggest pieces through bow access in my boat. It is also so wide that I do not have enough plywood left. With the original plan I still need to make 3 more layers to finish the mast sole and 4 more layers for mast step (the collar section to hold the mast).

I would like to determine how much surface area I need contacting the hull on the beveled edges of the mast step. I hope that I already have more than enough. If that is the case then I will cut off the aft end of each layer such that I have the required amount of surface area. Then with a little more positive thinking this will actually fit in the boat.

Does anyone have a rule of thumb for how much hull contact is needed in this type of mast step?

Scott.

Update:

After some searching I found the comment I remembered from Arne. It is on the caption of a photo here. He says, 'With a contact area of at least 1500cm2, that thing will stay put'.

I think I will do some measuring and see how close I am to that number.

I made a lot of dust. Much more than I expected. I hope this indicates some progress.

I might have considered attaching a vacuum hose to the angle grinder some how if I knew how much dust I would be cleaning up later.

I did not grind the entire mast step area down to translucent glass. I tried to take at least a small layer off everywhere. Any opinions after reviewing the photos would be welcome. I plan on wiping the area down again with towels and acetone just before I epoxy the yet-to-be-made plywood layers.

The weather is reminding me why I like the inside 'control point' from PJR so much. It is raining and raining. I hope someday I will have a boat that is able to sail in the rain while I am inside dry and comfortable.

Now I am waiting for dry weather so I can cut and shape plywood. Too messy to do in the garage.

Scott

Arne wrote:

[...]

PS: Check this: http://bit.ly/2sf2tsW

Hi Arne,

I have been studying your mast step and partners document for some months now. I have never considered any other way to build a mast step. My only doubt is if I should use the same total thickness on my S2 6.7 (998kg) as you did on your Folkboat (2150kg). I am not concerned about how much labor is involved. I am concerned about adding too much weight to the bow of my boat.

In addition to the very helpful instructions I also enjoyed these comments:

"With the sail finished (Jan. 2015), it was time to set to work on the hard bits."

"to have a mast step come loose [...] would turn the big mast into the mother of all can openers. "

When I was working on the sail it did not occur to me that the hard part was yet to come!

Scott.

Anonymous wrote:

Phil, if you are following along I would appreciate your opinion on how thick and wide to make the mast step. As you may recall the displacement of your ComPac is close to the displacement of my S2 6.7

Is 6" tall, total, too much? Is 2" for the collar too much or too little? 

I think I had six beveled layers of 1/2 inch ply for the base, enough to to have good contact area on its bottom and the beveled edges. The upper section that held the mast is probably 2 inches thick.  Brenda B’s hull is flatter than some so the bevels may be flatter with slightly more surface and contact area for the epoxy, first well coated (plywood edges soak it up pretty well) then glued with thickend epoxy. I also glasssed top edge of the base to the hull.  If I get out to the boat tomorrow I’ll double check.

Thank you for the responses. I ordered a water level. I will plan on leveling the boat on the trailer using the bottom of the bootstripe and then make a fore-aft and port-starboard 'level' line on a bulkhead or some other place.

I was thinking I should sail the boat with the original rig at least once before taking the existing mast off. But it keeps on raining! I am not against sailing in the rain but trying to learn how to step a mast and launching a boat for the first time in the rain seems like it could cause problems.

Summer is short. I think I may skip the sailing this summer and stick to working on the conversion.

Scott.