Building a Fiberglass Tank

[Rusty]

I recently decided to build a tank for my “Strand Shark” project which is a 1938 Rollfast or Hawthorne Zep frame. The original tanks for these bikes fit completely inside the opening and did not cover the bars at all. I want this tank to partially cover the bars so it looks a little more streamlined.

What I am working on now will become the inner plates for the tank halves. These two plates will meet in the middle and the tank halves will be built onto them.

Here I have clamped a piece of wood to the back side of the frame to give me a surface to work on. I have placed some blobs of modelers clay on the wood to support the parting board.

The parting board is just a piece of 1/4” hardboard cut to fit in the opening. I sprayed some scratch filler primer on one side and then sanded it smooth. Here I have squished it down onto the blobs of clay until the top surface is even with the marks I made on the centerline of the frame.

Next I filled in the gap with some modelers clay and then scraped off the excess with a razor blade.

 

[Rusty]

Here I have applied some .020 thick sheet wax to enlarge the diameter of the frame slightly. This is just to give the parts some clearance so that they will not be line to line with the frame.

Next I sprayed a few coats of PVA which is a mold release.

After the PVA was dry I decided to build a clay dam around the edges just to keep the resin from running all over creation. This probably should have been done before spraying the PVA. Oh well. :mrgreen:

 

[hewey]

Looks great, looking forward to seeing how it comes out.

 

[Rusty]

Thanks hewey. More on the way...

Good to go! Time to mix up some resin and get started. I use West Systems with 206 hardener. The 206 will give you about a 20-30 minute potlife depending on the temperature. The first thing to do is fill in the sharp corners to help reduce bubbles. For that I mix in some Cabosil to thicken up the resin so it will stay put.

Next I laid up 3-4 layers of 8oz cloth and let that kick overnight.

The next morning I removed the wood backing, turned the frame over and popped off the parting board. The green stuff is PVA. It is water soluble and wipes off fairly easily with a damp cloth.

 

[Uncle Stretch]

Hummm from the skills and knowledge of materials ....Look like an old surf board builder. :roll:

 

[Rusty]

More sheet wax.

 

[Rusty]

Hummm from the skills and knowledge of materials ....Look like an old surf board builder. :roll:

Yes, I surfed for many years, but was not a board builder. I have also been doing RC planes for many years. It was in the airplane hobby that I started working with glass, building molds and laying up fuselages. Here is one I did a few years ago. Haven't had much time for building since my kids were born though. :mrgreen:

 

[Rusty]

After I got the first half done, I realized that I would need some alignment pins in order to sand the two halves to the same shape after I remove them from the frame. I usually use those little stick-on rubber cabinet door bumbers but since it is too late for that now, I just made a couple of indentations with the tip of a drill. When I layup the other half, it will fill in the hole and make some little alignment features.

To build the clay dam I just roll out a long worm of clay and then flatten it by rolling a spray can over like a rolling pin. Then I slice it down the middle with a razor blade to get a straight edge.

Clay dam on. Now for a few coats of PVA.

Don't tell my wife I am using her hairdryer. :mrgreen:

Break time. My 6 year old daughter. She's the one that took the picture above.

 

[user 135]

Very cool. Great tutorial. Gonna "sticky" this for the How to Manual.

 

[Rusty]

Now to layup the second half. I like to "roll" the cabosil into the corners so I don't trap bubbles.

A few layers of cloth and its Miller time.

 

[Rusty]

Very cool. Great tutorial. Gonna "sticky" this for the How to Manual.

Sweet! :mrgreen:


The next morning I popped the halves loose and cleaned up the frame. I used a jigsaw to saw off the outer edge to get rid of the clay.

Here is the little alignement thingie.

Next I clamped the two halves together and sanded them to the same shape on my beltsander.

 

[Rusty]

Some fine tuning.

Also need to make sure there will be enough room for the headbadge.

And that's it for the inner plates! Next thing to do will be to pour some AB foam on them so I can shape the tank halves.

That's all I have for now. More to come next weekend. :mrgreen:

 

[ratdaddy]

that is so awesome. thanks for the step by step...it's incredible to see the steps and the craftmanship that goes on on this board.

 

[UncleKudzu]

oh, man, this is awesome! can't wait for next week's installment!

 

[jondutch46]

Yeah... I like this. Been thinking about building some 'glas tanks, too... got my own ideas but I'll watch to see how you do. Always better to learn from others than to make my own mistakes.

 

[onelesspedestrian]

oh, man, this is awesome! can't wait for next week's installment!

Yeah... I like this. Been thinking about building some 'glas tanks, too... got my own ideas but I'll watch to see how you do. Always better to learn from others than to make my own mistakes.

I agree! lookin' good!

 

[Rusty]

Thanks for the kind words guys.

I thought I had foam but then I realized that the stuff I had, had gotten hard in the can. So earlier today, I ordered some more from Fiberglass Supply (.com). I have to say that those guys are just awesome. He said it would go out tomorrow. Then I asked if there was any way he could get it to me by this weekend and he said he would make sure it went out today. I get great service from them every time I call. I cannot recommend them highly enough.

I also just ordered some of these Rare Earth magnets. I plan to use them to hold the finished tank halves together. These have 10lbs of pull (20lbs magnet to magnet). I think that should be enough but I will have to do some testing.

Finally, I got two of these lights. I plan to remove the mounting brackets and will have to figure out some way of mounting them on either side of the forks. Should look kewl.

Rusty.

 

[UncleKudzu]

hey Rusty, is what you've done so far going to be a mold, or will it end up being the final tank?

thanks!

 

[IronSpadeCycles]

Hey Rusty, where do you get the sheet wax? I need some, it makes perfect sense I don't know why I haven't thought of it sooner. Thanks man, Later Travis

 

[Rusty]

hey Rusty, is what you've done so far going to be a mold, or will it end up being the final tank?

thanks!

Hey UncleKudzu,
What I am working on now is the plugs from which the molds will be made.

Hey Rusty, where do you get the sheet wax? I need some, it makes perfect sense I don't know why I haven't thought of it sooner. Thanks man, Later Travis

I got the sheet wax from Freeman Supply. It comes in various thicknesses. I use the Thermo-Stable stuff so it won't melt while sitting in my garage. It is also nice for creating fine details. I used it to create the canopy lines on a Focke-Wulf P.I. that I built a while back.

http://www.rcgroups.com/forums/showpost ... tcount=108

Rusty.