Friday, November 16, 2012

T2-21 Build-Series #3

Now its time for the tub-deck!

KEP's T2 .21 Presentation

KEP's T2 .21 Freebie

KEP's T2 .21 Build Series #1

KEP's T2 .21 Build Series #2

First you need to glue in the front bulkhead cowl-mount doubler with medium CA glue.

Then you need to sand down all the top/deck protruding bulkheads flush with the tub-sides. A flat Great Planes bar-sander with 80-grit paper is what I use. Use a steady hand and look at what you are doing...

Here I have sanded down the bottom part of the bulkheads also flush with the tub-sides. You don't really need to do these at this time as you will glue the deck first. And it might be easier/better to sand them down when the deck is in place (the tub becomes more rigid to hold etc).

All top edges are sanded flush and smooth. 

I forgot to take photos of the actual gluing of the deck. But you use the same flat board covered with plastic food wrap as a base to start with. Then you use the long aluminum 90-deg L-angles again and clamp them to booth tub-sides. That's because you want the tub sides to be straight while gluing the deck. As the tub-sides are flat between bulkhead #2 & #3 (the engine bay). That's the area I will start gluing to the 1 mm deck. I add ZAP-a-gap medium CA to the top part of the tub-sides and the top of bulkheads #2 & #3. Then I turn that complete assembly (with attached aluminum angles etc) with the deck-side down and push it down to the deck-sheeting. Note that I use some simple guide lines on the deck plywood so I drop the tub-frame somewhat straight onto it. Hold it for a minute like that. Then add glue between the rear part of the tub sides and the bulkheads up to the radio-box deck doubler... And press down/roll the assembly down. I like to glue it gradually to get a good glue joint. When that has set - do the same for the rest of the rear of the tub/deck. And when that has set you need to do the front nose-part. That can be a bit more difficult as there is more radius. Use more glue here and have the kicker can close by or better yet - a friend that is ready to help out. Most of the time you need to use kicker here!

When the tub-frame has been glued to the deck - wait 5 minutes and then start to remove the aluminum angles. Now add a bead of ZAP-a-gap CA glue on all deck glue joints. Inside and out. Let that soak in for 5 minutes and then take a paper-rag and remove any glue that has not set yet. Then you either let it sit over night or use a light mist coat of kicker to the glued joints.

Trim down all the edges of the 1 mm tub deck. I start using a small model-plane with a razor blade and then use the standard Great Planes bar-sanders with the same 80 grip paper as every where else. Take your time and be steady on your hand, especially on the corners and edges so to speak.

Use a straight-edge 90deg angle tool and mark out where the deck openings will be. Use a soft pen.

Personally I use a cut-off disc in my Dremel and do the straight cuts first. After that I use a sanding block for the straight edges and a sanding-drum for the corners. Progress slowly...

Close-up of the initial cuts.

You need to go even slower when you are close to a bulkhead and tub-side...

If you haven't done them earlier - sand all the bottom protruding bulkheads flush with the tub sides so there will be no gaps when later on gluing on the tub bottom sheeting.

All holes in the tub-deck are done. :)

I use 2 mm thick small scrap pieces of lite-ply to reinforce the deck in two places. The front and back lip. Round off the corners and edges - these don't need to fit snugly so to speak. They are just there so the deck will be more solid at these locations.

The front deck doubler.

The rear deck doubler.

Done for now - next step is servo-mounts and cowl mount. Stay tuned... :)

KEP's T2 .21 "Inspirational" Article

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