Curved Pilothouse Window Hell!

[Rhosyn Mor]

This is a picture of a Dolphin 46 that Maritime Plastics did . Disclaimer, I do work for them part time

[speciald@ocens.]

I have curved polycarbonate windows on my dodger. They have not yellowed in the tropical sun. The only problem is rainbowing when looking thru them with polarized sun glasses. They are fragile and easy to scatch, too.

[TaoJones]

Originally Posted by Rhosyn Mor

Attachment 8425

This is a picture of a Dolphin 46 that Maritime Plastics did . Disclaimer, I do work for them part time

It's more "Full Disclosure" than disclaimer (A repudiation or denial of responsibility or connection) - but we get your point.

TaoJones

[s/v Jedi]

Gord: thanks, these didn't come up a couple of years ago... but still they only list 3/8" as clear and I'm afraid it's be the 30-sheet story again when I ask for gray ;-)

Rhosyn: That link is promising! But MR10 can't be formed so I'll ask if they have that.

ciao!
Nick.

[Christian Van H]

Originally Posted by Cheechako

lexan has visible ripples/distortion in it.

If it didn't, it will when I'M done with it!

[Christian Van H]

Originally Posted by Rhosyn Mor

Attachment 8425

This is a picture of a Dolphin 46 that Maritime Plastics did . Disclaimer, I do work for them part time

AWESOME! Can you do mine here in Trenton, NJ?

[bob kingsland]

Rhosyn, that's an awfully nice looking window.
My experience referenced above is mostly from cold forming metal; hot forming plastics will make the process much easier but Chris you'll still have to factor in some sort of bend allowance to get the flat pattern right.
Post pics!
Best, Bob S/V Restless

[Christian Van H]

Originally Posted by bob kingsland

Chris you'll still have to factor in some sort of bend allowance to get the flat pattern right.
S/V Restless

I confess I cheated to get the pattern. I used 1/4" black PVC sheet to rough up a pattern after first using thin cardboard. I was then able to clamp the PVC onto the 'house, and hand bend to check fit. I think...

[Rhosyn Mor]

I am not desirous of publicising my employer much more than has been already stated, but if you PM me I can give you more information., we do have some curved molds in stock for thermoforming

[Extemporaneous]

Originally Posted by Rhosyn Mor

Attachment 8425

This is a picture of a Dolphin 46 that Maritime Plastics did . Disclaimer, I do work for them part time

Don't you think your being a little mean posting this?

[Christian Van H]

After failing once again I have given in and contacted the experts. This is harder for me than it sounds, as this is the first time I have asked for outside help during this refit. I broke down and called Maritime Plastics (410-263-4424), and I'm really glad I did. They know their stuff, and seem to be both friendly and flexible. As for the attempt, my homemade oven simply could not achieve uniform temperature throughout the piece. After failing with both test pieces, I couldn't risk failing on the "real deal". I am now going about building molds, which I will bring to Annapolis for MP to form my new front window with. Live and learn. C

[44'cruisingcat]

You could try making templates from 3mm MDF.

I could see what a hassle curved windows would be, so I tried very hard to avoid them, without having the boat look too boxy. These are my MDF templates, painted black. The heavily curved part is solid fibreglass which will be painted black to look like the windows.

The real windows should be fitted soon.

[Christian Van H]

44, that looks sweet! I wish I had the opportunity to design my pilothouse, but it was already 30 years old when I bought her! The boat had a terrible window mounting method...almost a joke. The new windows will be MUCH stronger. Your cat looks like it can go 100 knots standing still! How thick is your Lexan / Plexi to be? We are using 3/8" light grey tinted...

[Christian Van H]

Here's pics of our progress toward new curved pilothouse windows. After conferring with the really nice people at Maritime Plastics in Annapolis, we set about building molds for our windows. You can see from the pics that we basically bent thin marine plywood around the actual area the windows mount, then epoxied 3/4" plywood with saw kerfs cut to allow flexibility INSIDE to stiffen and lock the shape into the piece. After removal we built frames to mount under the pieces, then covered the molds with synthetic Moleskin (turned inside out for the smoother finish) with spray glue. We are ready to go, and will venture down to Annapolis Thursday morn to give it our best with the help of MP. I'll let you know how it goes... Chris

[Christian Van H]

Hi all! Well, I'm finally out of hell! The windows are DONE. Here's what we did; after the last post, we took the molds down to Annapolis along with our rough Lexan blanks. Although we followed the strict specs listed on the manufactures handbook, we were unable to get a good bend even with all the proper equipment. One of Maritime Plastics owners, Keith suggested we fabricate these two corner windows from Plexi as the bending temperatures are much lower and have a much larger margin for error. Althogh we had taken the advice for using Lexan directly from the Dashews Cruising Encyclopedia, I was ready to try ANYTHING to put some glass in the hole. We let them bend and cut the Plexi, and they finished in record time. Attached find a pic of the finished product. Live and learn!

For more pics log on to our new website here: www.anacapas.com