Engine hatches, how to build
 

I'm looking for info on how to build an engine hatch. Materials, technices, etc. It does not have to be very elaborate. It must be strong enough to walk on though. Something like what is pictured.

Re: Engine hatches, how to build
 

I'm building a set of race hatches for my Cig. A wooden box frame with 4 crossmembers all screwed together with galvinized screws. Then covered with 12 oz triaxial fiberglass with epoxy resin on the bottom and 10 oz on top. I'm not done yet but heres a few tips for you:
1. Every edge that you're putting fiberglass on has to have a radius or it will not stick right
2. You're first fiberglass job will most likely become you're first fiberglass repair job too.
Good Luck, Theres some people that a really talented with that stuff on this board, I'm hoping to pick up some tips too.

Re: Engine hatches, how to build
 

Dave
I just had one built out of Kevlar by Fiberglass Plus. I wanted to eliminate the sunpad and add scoops. If you decide to have it done by a professional, I can highly recommend this company.
Ed

Re: Engine hatches, how to build
 

Thanks for the info guys. I think over the winter I'm going to do some experimenting on a small scale and see how it comes out.

Dave, how do you get the topside to be smooth? Did you gelcoat it after the fiberglass? What kind of wood did you use?

Re: Engine hatches, how to build
 

I'm not done yet but I plan to get it smooth using an epoxy "flood coat" and then lightly sanding and then painting with awlgrip. I have to paint it because the epoxy I use will yellow a little because of UV rays. For wood I used poplar for the frame and oak 1/4 inch plywood for the deck. Keep in mind I don't really walk on my hatch, I have stood on it and jumped up and down to test for strength but if you want to walk on it I'd use 1/2 inch plywood. Also, don't buy fiberglass or resin from West Marine or any other boating store, It's a rip off. Theres plenty of places you can find online that will ship it to you if you don't already have a local source. I'll post pictures of my project soon so hopefully you can learn from my mistakes.

Re: Engine hatches, how to build
 

Hey Dave,

Did you glass one side wait for it to cure and then glass the other side? I'm trying to visualize how it would be done without a mold.

Re: Engine hatches, how to build
 

yes, exactly. I did the bottom first so I could wrap the fiberglass around and the seam wouldnt be visible from the outside

Re: Engine hatches, how to build
 

Do you have any of their contact information? What was the cost? :D

Re: Engine hatches, how to build
 

I was thinking I could make a mold to make the job much easier. I was thinking of using wood but the glass would probably want to bond to it. What can you make a mold out of or what can you put on it that would keep the glass from bonding to it?

Re: Engine hatches, how to build
 

MDF (Medium Density Fiber Board) works well for molds. Hard part is figureing out the reverse. The way that they ussually do it is make the part, then make the mold out of the part, then make your hatch in that. For a one off then your best bet is to just make the hatch and glass it IMO.

Jon

Re: Engine hatches, how to build
 

Thanks Jon,

For something like I want to build I didn't think figuring the reverse would be too hard. It's just a rectangular box. I figure I can make it slighty larger and deeper.

Dave M.

Re: Engine hatches, how to build
 

Ya if you are going square box then you probably are ok. The MDF will work for you. As was mentioned earlier you can not do hard corners in a mold either so make sure you have the corners rounded off or the glasss will lift and create bubbles. You can always fix these things later and or glass hard edges in after you pup the thing out of the mold. Also make sure you will be able to pup the part out of the mold. In other words make sure that like the top is not wider then the bottom of the hatch (as it would sit on the boat) thus making it neccasary to break the mold to get the part out.

Jon

Re: Engine hatches, how to build
 

You can make your mold from wood. To keep the resin/gel from sticking coat the wood with PVA or release wax. Use clay to seal the seams and make your radiuses. If you are using reverse angles make sure you have planned a way to remove the mold from the part because the part will not release from the mold. Either way don't expect the part to just fall out.

There will be finish work post mold because the wood grain will transfer to the part.

Also, be sure your mold is stiff or shrinkage and heat of the curing resin can cause the mold to warp.

Re: Engine hatches, how to build
 

build a wood sand box the shape of the hatch you want. Tape the inside of the the wood with box tape. Yes box tape. if every thingis true you can lay in 60 mils of gel before you glass it up. Pop the part and wet sand it. of you have the tools and knowledge this should be an easy project. go buy a pair shoes and use the box as a small scale experiminet. Make sure you use a structure on the outside of the box from keeping it fro moving. You could make one hatch in 8 hours.

bottomsupboatrepair.com :evilb:

Re: Engine hatches, how to build
 

Thanks guys, great ideas here. I was planning on taking Bill's advice and doing a test run with a small box.


What type of glass should I use? I looked in some catalogs at the sizes available. Should I try to work with large pieces (I know it's harder) to avoid seems? The hatch is going to be approx 66" x 36".

My current hatch has the back seat built in. I like that, easy engine access. I hope to include that in my new hatch. See picture.

Re: Engine hatches, how to build
 

What's wrong with your current hatch? Is it fiberglass on both sides?

Re: Engine hatches, how to build
 

It is glass on both sides, the outside is gelcoated. If you notice in the pic, I attached the 2x2 angle iron to raise it a few inches. It BARELY clears the motor now. If I move the angle iron up any more the hatch will be higher than the gunnels and look crappy. Also, I had to doctor the way my hinges attach in the back. I don't think I can go any higher. I want to add CMI headers and need some more clearance. The raised part of the hatch in the back used to be flush with the back of the boat. I thought about modifying the existing hatch. I don't want to mess with it because I know I always have that to fall back to if my new project doesn't work right.

You know how it is. Winters coming, and I need/want something to do.

Re: Engine hatches, how to build
 

Got ya!

Re: Engine hatches, how to build
 

Thanks for the recomendation. I am also planning on eliminating the sunpad/engine hatch cover combo for an all glass unit. Can you provide the telephone # for Fiberglass Plus? Richard

Re: Engine hatches, how to build
 

Fiberglass Plus
Point Pleasant Beach, NJ 08742
(732) 899-8523

Re: Engine hatches, how to build
 

How's Frankie doing??

Re: Engine hatches, how to build
 

When I left his shop he was wealthier!

Re: Engine hatches, how to build
 

Thank you sir!!!!!!!

Re: Engine hatches, how to build
 

Dave, Dave, Dave,
What am I to do with you. I have every and any hatch configuration you could possibly ask for. I could make you a new Y2K scoop hatch for your boat , or the older style boxerier scoops. Let me know. It would be a nice winter project for me.

Rick

Re: Engine hatches, how to build
 

Glass over wood is going to be heavy. I made hatches from panels that had a foam core with a glass skin on the outside. Light weight and it minimized finish work, you only needed to glass the seams. Easy to work with. Molded in 2 side scoops that look like jet intakes and a scoop on top.

Re: Engine hatches, how to build
 

Sounds cool! Do you have any pictures?

Re: Engine hatches, how to build
 

Dave, Lets have Rick build 2.
I don't want a scoop, just one that is flat and eliminates the pad.
Rick, I am serious. Do I contact you or go through JC.

Re: Engine hatches, how to build
 

Thanks Rick, I'll give the shop a call sometime soon.

Re: Engine hatches, how to build
 

Sounds good. I think I could probably manage to build something but what would it look like? :eek:

Re: Engine hatches, how to build
 

Dave
I will take some pictures over the weekend and email them to you.

Re: Engine hatches, how to build
 

Pat ... without the pad will it be just Gel ? ... I have had thoughts about a cover with no pad but carpet ...inlaid into the cover .... real nice carpet with maybe a logo or design ... be nice for standing/walking on and even a lawn chair spot for races , air shows ...ect ....

Re: Engine hatches, how to build
 

Yes, just white gel-coat, maybe some strips to match the deck or a decal.
The sun pad takes a beating from people climbing up from the swim platform and stepping on from the dock.
Both of my Donzis just had a simple hatch with no sun pad. I'd skip the scoop, no blower motor or other clearance issues.