Many of you have helped me formulate how I'm going to do the hull repair and bottom job on my N5.8...invaluable advice and thank you to all for the time you have taken to help. I will pay it forward at some point in the future.

I've sourced the materials I need and am now trying to figure out the tools I'll need part.

1. I know I need a grinder. Is a 4 1/2" okay?
-I think a fellow member told me to use 60 grit to grind away the bottom fiberglass damage. Agree?
-Any other advice on this?

2. I suspect I'll need to cut out some damaged fiberglass. Should I just grind out the damage or do I need a reciprocating saw?

3. What kind of sander? Orbital? Belt? Both? What grits do I need for the various stages? (I will not be gel coating, but rather, painting...not sure if that changes the answer or not)

4. Respirator - a more permanent one that has replaceable filters? Or can I use the 3M disposable one that is cheaper and is worn out when you can smell the vapors? Not sure if one of these disposable types will be enough to complete both hulls.

Thanks in advance of the advice on this!

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Jeremy Soder
Nacra 5.8
Allen, TX
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1. Yes
2. Grind
3. Orbital, 60
4. I don't use one.

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Greenville SC

Offering sails and other go fast parts for A-class catamarans
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4. When it's just once and you are working outside it could be okay, but still when grinding/sanding at least disposable dust respirator. I use a permanent activated carbon filter with dust filter on top. But i work inside and with polyester, gelcoat and spraypaint as well. It's a 3M actually.

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Stefan, Denmark.
H14,H16,P16,P18,SC17,N5.8
Team StaySail
http://www.staysail.eu
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I used a Dremel with a stone bit to follow the edge of the damage but your job is a bit bigger than any I have done. If you are buying tools for a one off job you may never do or use again go to Harbo Ffreight. If you signed up on thir mailing list online you get all th sales and pick stuff really cheap. I used jitterbug type palm sanders mostly on mine. You can get a full on respirator with replaceable filters at Harbor Freight as well for under $15 and it is more comfortable to me than those dust mask type filters.

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Dustin Finlinson • Magna, UT
Member: Utah Sailing Association
1982 Prindle 18
1986 Hobie 17
1982 Prindle 16
1980 Prindle 16(mostly)
1976 Prindle 16(mostly)
Check out "Prindle Sailors" on Facebook.
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disposable mask ok

orbital sander better than belt

Those 4 1/2" angle grinders can be had for $20 & work very well. Make sure you use a grinding disc, not a cutting disc. Also, hold the tool so the disc is parallel with the surface to be ground. This gives pretty fine control over the removal of material. If you hold it 90* it is very difficult to achieve a smooth finish.
For large/long areas, such as the entire keel, I would use a sander, they give better results on large fairly flat areas.
Don't get to hung up on the grit #, you can accomplish the same thing with 400, it will just take a long time. Something like 60 grit is pretty coarse, & allows quick removal of material, at the cost of leaving coarse sanding marks. You don't really care about initial sanding marks, as the resin will fill them in.

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Hobie 18 Magnum
Dart 15
Mystere 6.0XL Sold Was a handful solo
Nacra 5.7
Nacra 5.0
Bombardier Invitation (Now officially DEAD)
Various other Dock cluttering WaterCrap
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One word on respirators: Be sure to match the respirator to the job. I know this is common sense, but I've seen people painting with a dust mask on, assuming it'll cut the fumes. I've also seen people using an acid gas / organic vapor cartridge in a respirator when they're sanding, assuming it'll cut the dust. If you're generating dust, use a dust mask or have a dust filter in your cartridge. If you're using volatiles, an organic vapor or acid gas / organic vapor cartridge is called for.

In ALL cases, your best bet is to ventilate very very thoroughly. Respirators can only work up to a given concentration level in the air. Past that they're not doing much for you. So if you lower the concentration through ventilation, your respirator won't have to work as hard and will be more effective overall.

Tom

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Tom Benedict
Island of Hawaii
P-Cat 18 / Sail# 361 / HA 7633 H / "Smilodon"
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I recently went to Lowes and bought about one of each grinding tool/attachment they have. I'm going to start w/ a flapper disc in my angle grinder and go from there. I'm hoping to return all the unused leftovers once I find something I'm happy with.

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Rob
OKC
Pile of Nacra parts..
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Thanks all for the advice. Transporting the boat to my buddy's barn tonight and we are going to start removing the hulls. I will take lots of pics so that some other hapless chap can benefit in the future. The last puzzle piece I still need to figure out is how much cloth to buy. I'm still undecided on whether to only fix the problem spots (only the starboard hull leaks) or to just do it right and re-glass both hulls entirely.

Unless I hear a vote to the contrary, I'm leaning on doing the complete job. If so, then part of this last puzzle piece is how much to grind away and lay new.

Do I just grind away the good areas too, but to a more shallow depth and maybe only lay one new layer of glass?

Rather than grind away the entire hull bottom at once, should I work in sections so that I can use the existing hull as a guide for shaping the new bottom? My fear is that I grind the bottoms away and start laying up new glass but in the process create a new hull shape becuase I don't have a guide. Maybe I should youtube a video on doing an entire bottom job at once...surely there must be some tricks here.

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Jeremy Soder
Nacra 5.8
Allen, TX
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I think laying glass on the entire thing is overkill. Just repair whats broke.

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Dustin Finlinson • Magna, UT
Member: Utah Sailing Association
1982 Prindle 18
1986 Hobie 17
1982 Prindle 16
1980 Prindle 16(mostly)
1976 Prindle 16(mostly)
Check out "Prindle Sailors" on Facebook.
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Just fix what's broke. Maybe a strip of glass along the bottom to handle any future beach wear.

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Uwe
94 Prindle 19 - "überKat"
DFW, TX
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