The Backdrop is Built

A major milestone was completed this evening:  The building of the backdrop is done.  The backdrop itself isn't done but the actual construction related to it is.  Since I was nearing the end of this phase of my layout I decided to take some pictures to document just exactly how I was doing things.

The frame which holds the backdrop is made from 1x2's.  They're cheap (about 85 cents each) and it only takes 4 to build an 8 foot section.  I start by marking where the cross beams go on the posts then laying them out on the floor with all the tools and supplies I'll need.

When I do the marking, I mark both the left and right sides at the same time so that they lineup perfectly once assembled.  To connect the cross beams to the end posts I use a corner clap and clamp everything in place.

I then drill counter-sunk holes...

...and screw in at least two 1 1/4" wood screws in.

Once all four corners have been connected, I use some scrap wood that I have lying around to make angle brackets and install those.  I had a lot of 2x2 scrap around so that's what I've been using.

Placement of the corner reinforcements is up to you. I usually only put 2 per frame, however since this frame was the last frame I decided to add two to the end.

Just in case you forget to cut the tops off, like me, it's not too hard to jam the whole frame into the miter saw.

With the frame built, it can then be propped up into place next to it's neighboring frame.  If it's the first frame you're building, you can use the roof, walls, floor, or even benchwork to temporarily clamp up supports to hold it in place while you work.

Once popped in place, I line up the two frames then clamp them together.  Once clamped I counter-sink the same 1 1/4" screws into them, bolting the two together.

After the frames have been screwed together, it's time to mount the actual sheet that will be the backdrop.  Before we can do that however we need to prep where it will start.  The previous sheet is likely bowing a bit and even if it isn't now, it probably will be later.

The best way I've found to level out two sheets meeting is to add a 2x2 behind them that they can both screw into.  Each sheet will overlap exactly half of this 2x2.

With the "bridge" 2x2 mounted in place, it's time to add the backdrop sheet.  I went with the material that's been a tried and true choice of model railroaders for decades:  1/8" masonite.  It's fairly inexpensive, easy to cut, and can be bent without to much effort.

I work alone so sticking an 8 foot by 3 foot sheet up on a flimsy frame takes some fore thought.  One approach I've found that helped a lot is to make "helper feet".  These are small scraps of whatever you've got with a screw hole on one side.

Make up 2 to 3 of these then screw them onto the lower cross beam of the frame.  They will act like a mini shelf when you're trying to put the sheet up and position in where you want.

With those in place the backdrop sheet can be lifted up and set into the approximate location.

Once it's up there I then position it exactly where I want and clamp it in place.  You'll notice in the above picture the sheet doesn't reach the top of the frame.  That's actually not the case.  What's happening is the lower frame cross beam is sagging under the weight.  To this end it's better to use a step stool or ladder and put the clamps on the top of the frame to make sure everything turns out level and straight.

Then comes the last part, screw it onto the frame.  It's easy.  Just be sure to counter sink all the screws and you're done.  Do that five more times, or however much you need to for the backdrop and you'll end up with a whole sweeping set like this:

Before you can paint the backdrop the surface needs to be prepared.  This entails two things:  Covering up the screw holes and hiding the seams between the sheets.  Handling the screws is easy -- just spackle over them.

WARNING: On the first half of my layout I just spackled over the seams between the sheets.  Bad idea.  After a few weeks of natural movement (expanding and compressing based on heat or humidity) the seams between the boards began to reveal themselves.

To counter this for the 2nd half of the backdrop, I decided to put drywall tape over the seams this time.  The drywall tape is a grid-like tape that is about two inches wide and likely comes in a bright yellow cover.

With the tape up I then began to fill over it with spackle.

The brand of spackle I use is pink when it's wet but turns white when it dries.  Here is what it looks like about and hour and a half after being put up.  You can see it's mostly white with pink spots.  Give it a good 3 to 4 hours to fully turn white before continuing on.

That's it for now.  In the next post I'll look at finishing the spackle, priming, and painting the backdrop.