ned help fabricating a new fiberglass sliding hatch for a hunter 25.5

[charliebelting]

Just bought a hunter 25.5 missing top hatch. Is there a way to make a neg mould for it and then make a fiberglass positive for it. where do I get glass cheap? Would polyester resin w/ insulation glas, got tons o fit around, work?
Better idea- anybody got a parts hunter 25.5 boat around?
Charlie

[sailingdog]

If you have access to another Hunter 25.5, you can make a mold of the companionway slider off of it... if you can get them to let you take it off.

As for fiberglassing it up yourself....I would recommend using EPOXY RESIN, since it is a bit more forgiving than polyester or vinylester resin. You'll probably need some balsa core material as well—like Baltek ContourCore. Don't use insulation fiberglass, it is really not the appropriate material, since it is designed to not lie flat and will probably yield a fiberglass layup that is resin heavy.

Order your fiberglass from someplace like www.fiberglasssite.com and your epoxy resin and hardener from Progressive Epoxy Polymers and Resins - Epoxy Paint and Repair Products / Marine and floor coatings.

If you're not experienced in fiberglass work, it might make far more sense to order one from Hunter. If you call them, they may have spare parts in stock.

[charliebelting]

Sailingdog,
Thanks for the info. I called hunter and they dont have any parts for a 1979 hunter 25.5. Too old.
I have worked a little w/ resin/ glass before. Now If I can find a similar hatch, I can duplicate it. Or else I will have to design it myself.
Thanks for the links.
Would it be worth it to list a request on sailnet to ask if anybody has a 1979 hunter 25.5? in the Los Angeles area that I could possibly take a mould of.
Where would I make that request on sail net?
Appreciate it !!
Charlie

[sailingdog]

This thread might be a good place to make such a request.

[TQA]

Making a mould then pulling a single from it is going to be a LOT of work.

In your position I would make one from wood and cover it with Glasscloth and epoxy. Maybe laminate two layers of thin plywood if you need a curved top.

Build the frame first, maybe using some nylon as runners if there is a metal edge to slide on. Get it to slide correctly then add the top. If you want lots of curvature on the top beware of pulling the frame out of shape. [ Don't ask me how I know about this ]

Lots of help here WEST SYSTEM | Use Guides

If you must use polyester resin it has a reputation for not sticking all that well to wood.

[zz4gta]

If it's an older boat like you say, I'd remove the factory "tracks" and replace them with one that'll hold a flat piece of acrylic as a sliding hatch. In my experience they somehow seem to seal better than the older designs.

[sailingdog]

You'd want to have a curved piece of 3/8" or 1/2" acrylic for the companionway slider.

Originally Posted by zz4gta

If it's an older boat like you say, I'd remove the factory "tracks" and replace them with one that'll hold a flat piece of acrylic as a sliding hatch. In my experience they somehow seem to seal better than the older designs.

[TQA]

How would you go about putting a curve in a piece of 1/2 inch acrylic? Never done that.

[sailingdog]

Originally Posted by TQA

How would you go about putting a curve in a piece of 1/2 inch acrylic? Never done that.

I'd probably cheat and curve two pieces of 1/4" acrylic and then laminate them together.

[Bloke]

It is done with heat
Any plastics fabricator can curve it for you.
(they may even have an offcut they can sell you)