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Re: hatch lip help
By:Steve McDonald
Date: 3/27/2000, 3:00 am
In Response To: hatch lip help (tom Preska)

> I am trying unsucessfully for the second time to make a hatch lip out of
> fiberglass for my exped. I am using pva but i can only get one quarter or
> so of the lip to release the other half has to be forced and ends up
> deforming. Should I wait until the epoxy is harder? It has been 7 hours
> since I applyed it east system slow hardner. The epoxy got into the space
> between the hatch and the deck. and I thought if i waited any longer i
> would have a solid deck again? Any suggestions? Any thing better than PVA?
> I used two coats. HELPPPPPPPPPPPPPPPP!

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Mold-Release Tips:

Are you also using wax as a mold release base, under the PVA? Some types of mold-release wax, such as Meguiar's, are not compatible with PVA. My number one choice is ordinary Johnson's Paste Floor Wax, available at a grocery store. Some other brands of mold-release wax are specially formulated to be used with PVA and can be found at professional fiberglass supply dealers. Put on 3 or 4 coats, allowing an hour to dry between applications. Then put on the PVA. Are you spraying the PVA or brushing it? You can't put on two coats, if you brush it, as the 2nd coat will dissolve the first. If you brush it on, use foam Poly-Brushes. To spray on PVA, a good method is to get a small PreVal aerosol bottle and cartridge, which allows you to use your own paint or other liquid. These are low-cost and can be found at some paint stores.

It might help if you let the resin harden more before popping it off. The rigidity will allow it to break loose better, without distortion. Epoxy takes longer than polyester to get fully rigid, unless you heat-cure it. Try out any new mold-release system on a small, throw-away object first, to make sure it will work properly.

Small, highly-curved objects like cockpit and hatch lips are difficult to mold, without a lot of practice and air bubbles are hard to avoid. You might try putting on only one layer of resin and cloth at first and letting it set up, before applying the others. It's easy to damage the mold-release and have breakaway problems, if you jockey-around all the layers, in one application. The first hardened layer will protect the mold-release, as you manuever the rest into position and air bubbles are easier to eliminate.

Use the resin very sparingly, mixed in small batches, for such a project. The less resin you dab on, the less likely it will be to run down into places where you don't want it. Make sure to put mold-release on every surface onto which the resin might seep.

Steve McDonald

Messages In This Thread

hatch lip help
tom Preska -- 3/26/2000, 11:01 pm
flush hatches with composite gasket lip
Vaclav Stejskal -- 3/29/2000, 5:29 pm
One step?
mike allen ---} -- 3/30/2000, 1:02 am
One step hatch seal layup
Vaclav Stejskal -- 3/30/2000, 4:10 pm
Ideas plus Orientation Change
mike allen ---} -- 3/31/2000, 3:11 pm
flush hatches
Vaclav Stejskal -- 4/1/2000, 1:02 am
Re: flush hatches
mike allen ---} -- 4/3/2000, 11:48 am
Re: flush hatches and philosophy
Scotty -- 4/1/2000, 2:14 am
Re: flush hatches and philosophy
Vaclav -- 4/1/2000, 3:09 am
Spacer Req'd!
mike allen ---} -- 3/27/2000, 10:57 pm
Re: Spacer Req'd!
tom Preska -- 3/27/2000, 11:55 pm
Re: Spacer Req'd!
mike allen ---} -- 3/29/2000, 12:07 am
Re: hatch lip help
Warren Ross -- 3/27/2000, 3:21 pm
Thanks to all
tom Preska -- 3/27/2000, 9:10 pm
Re: hatch lip help
Kent LeBoutillier -- 3/27/2000, 6:15 am
Re: hatch lip help
Steve McDonald -- 3/27/2000, 3:00 am
Re: hatch lip help
Randy Knauff -- 3/27/2000, 2:40 am