Making a door

[Cat futrell]

Well I would like to be posting updates but sadly I am not. The boat builder that we had to build a new door for out 1973 Love bug fell through. I'm going to make an attempt at it. Worst that will happen is, I will lose the cost of the resin and mat, ... best thing.. I will have a door, and one way or the other I will learn something

I am pretty set on having a door as much like the original as possible. By that I mean a fiberglass door that matches the contours of the shell.

I plan to create a template from the outside and cover it with mylar, so will be laying up fiberglass from the inside, this will enable me to get a smooth exterior on the door. I have limited knowledge about available materials. Thus far I have used various weights of mat, and roving. I am wondering if there is a finer type of glass that could be used to help achieve a smooth surface on the exterior of the door.

We will be painting the camper as some point so gell coat is not needed.

Input please?

Cat

[Thomas G.]

Lots of tutorials on YouTube.

Here is one:

Making A Fibreglass Mould - YouTube

[Cat futrell]

Thanks Tom,

But I'm not using gelcoat. doesn't that make a difference. I haven't found on that doesn't use gelcoat.

cat

[Cat futrell]

a video, I mean

[rabbit]

You are ambitious, I'll give you that. There's fabmat, cloth, heavy woven roving, and biaxial or a combo of cloth or roving and mat. Without a sprayed gelcoat, I would think fabmat would provide a relatively smooth surface in contact with the mold. I think you have done enuf around wheel wells and patching to know how to catalyze, wet out, hard roll.

What would worry me would be mold construction. I don't know how the contours of those LB doors run. Are they curved top to bottom only or compound. Either way, to have an accurately fair surface in continuity with the surrounding trailer, you'll need to determine setback to framing based the thickness of the material you use as skin. I think this means cross-sectional drawings in most cases unless you're going to develop some sort of close interval eggcrate framing on which you could maybe flush up and fair the voids with bondo. I don't know anything about the mylar. Is it the mold release or a mold skin? I guess your guy who can't do it can tell you how (those who can do and those who can't teach). I'm afraid I'm not much help; it's only been 37 yrs. since my involvement with rudder molds for sailing cruisers and later some thermoform tooling for commercial aircraft class dividers. Keep us posted, Cathy.


jack

[Thomas G.]

I've never done a large FG project, so hopefully the veterans will jump in. I'd think that without gel coat, much would be the same.

I found a site that discusses mold making including without gel coat, for what it is worth.

mold making

[Cat futrell]

Thanks Jack,

I am thoroughly impressed and feeling a little less adventuresome since I don't understand some of what you said.

I'm have two possible plans of action. Let me preface by saying that the door has a very slight curve at the top and more of a curve at the bottom. Vague, I know but this is what I am thinking, I think?

possibility #1.. use a piece of door skin and shape it to the the door curve by wetting to soften, then laying it against the outside of the door opening. clamp it there untill it dries and then glue pieces of foam to the outside of the door skin to reinforce the shape creating a "mold". Fiberglass doesn't stick to mylar and it is a smooth surface. spray adhesive the mylar to the wood mold and lay out the glass onto the mylar. this should yield a shape that when cut to size will correspond with the door opening.

2.. ooooor, use a piece of plexiglass instead of door skin and create the curve with heat and pressure.

[Cat futrell]

thanks Tom

[FRED SMAILES]

Take a window out so you have access to the inside other than the door.
Cover the door area with plastic. From the inside screw a thin piece of plywood to the opening in the shape of the door putting a few cross the door saw cuts in the plywood to help the ply easily take on the door contour.
Grind any protruding screw ends off the outside of the ply. Apply several layers of resin soaked glas to the ply. allow each layer to harden and sand off any protrusions to keep it as smooth as possible. Use auto body filler to create a smooth paintable surface when the door is complete. Once you have it up to about quater inch thick let it cure for a couple days.
Remove the screws and the door from the trailer. To reinforse it put material (cardboard ,foam, wood frame but keep it light, you just need depth) on the inside to create volume and glas over that to get body.
That would build a door on my Boler, I assume you trailer is similar in design. I have personally used this method on several projects with great results.
Start, don't stop, you'll get it!
Fred

[Ron in BC]

Whew, big project to offer a few words of help on

Re: 1st layer to make best surface. If using gelcoat then light mat prevents the roving pattern from "telegraphing" through. If not using gel coat then surfacing mat should be used with the first coat of resin. It looks like kleenex and does the same, gives a better surface for finishing.

Generally speaking laying up the finished product in place would be difficult. Skilled tradespeople sometimes repair major damage to boat hulls that way but not suitable for a first time effort.

As several have suggested, some variation making a mold covering the opening with a skin, laying up some battens or stiffing ribs to make it stay in shape when removed would be the way I'd do it. Then remove and do your layup with the mold horizontal.

Good luck

[Cat futrell]

Thanks Rob,

Will try to locate surface mat tomorrow.

[rabbit]

I was trying to think of that thin mat. We used to call it "veil."

jack

[Ron in BC]

I should also have said that the really important part of the whole project is getting the mold to the proper shape. It should overlap the exterior of the door opening about an inch. A good test will be to reinforce it, appearance is unimportant, rigidity is very important. After removing it, put it back in place. If it has sufficient rigidity it will conform to the trailer shape without gaps. If not, fix it Getting the mold the right shape is much easier than trying to make the finished part fit afterwards.

Laying up the finished door is easier by comparison.

I'd lay up the door skin. Mat and roving or fab mat. Remove from mold. Trim to finished door shape. Place back on mold. Slop some resin on and place 1/2" foam on, held down with weights. A good reason to have a strong mold. Trim foam as required and cover with a layer of mat. Makes a stong insulated panel.

Ron

[Steve Hammel]

Wouldn't it be easier to just build a stick frame, as light or as heavy as you wish, and then skin it in exterior grade fiberglass sheeting? For that matter you could even use steel or aluminum. All are readily available and easy to work with. Just build a stick frame, include bracing for your hinges, door lock, and window. You could then skin it in "thin" exterior grade wood and cover it with resin or use steel or aluminum. I was just reading a thread the other day where a guy rebuilt a boler (commercially) and totally rebuilt the door using this method. He had detailed step by step instructions. If I can find it I'll send it your way.

[Donna D.]

Originally Posted by Steve Hammel

I was just reading a thread the other day where a guy rebuilt a boler (commercially) and totally rebuilt the door using this method. He had detailed step by step instructions. If I can find it I'll send it your way.

Oh please post it here! I'd love to read how it was done.

[Thomas G.]

Originally Posted by Steve Hammel

........I was just reading a thread the other day where a guy rebuilt a boler (commercially) and totally rebuilt the door using this method. He had detailed step by step instructions. If I can find it I'll send it your way.

Was this it? http://www.fiberglassrv.com/files/BolerDoorFix.pdf

[Steve Hammel]

I've been reading a lot of Robert Johans posts lately. He has the one for repairing a door although interesting that is not it. Perhaps another one of his. I do remember that it included remaking the core of the door, re insulating it, re-skinning it, and installing matching wood veneer on the inside. Super good info. I've just been reading so much getting ready to do my own mod, I wish we had a private save area for stuff we want to refer back to. My memory is not what it used to be LOL!

[Steve Hammel]

Originally Posted by Thomas G.

Was this it? http://www.fiberglassrv.com/files/BolerDoorFix.pdf

No but that is pretty incredible. Probably out of the expertise of most of us, definatly me, welding aluminum.LOL!

[Donna D.]

Originally Posted by Steve Hammel

I wish we had a private save area for stuff we want to refer back to.

You do, it's called an spreadsheet (maybe like Excel). Put the URL in one column, the thread title in the next column. My spreadsheet is over 300 records and counting. Sure saves the bookmarks! IMHO

[Steve Hammel]

Duh, didn't even think of bookmarks. I'm such a dunce sometimes. I'm glad you're here to point that out Donna LOL!