Coving Corners

Sounds like the name of a town any where USA...Excellent techniques....and as always filled with tips to make ones efforts either easier or ending in better results...your scenery fading into the coving (pic 25 ) is very convincing...perhaps a step by step on the methods used to achieve the results you did will be the subject of future articles..hint..hint...Joe

Simple and effective

Really enjoyed this

This article encouraged me to reconsider a couple places on the layout where I wish I'd coved my backdrop corners during initial construction, but have always been afraid to tear out the adjoining Masonite sections to re-do it.  I never thought about coving over the top of them, but I love the idea.

Two questions:

1. Do you think it's possible to staple into Masonite sufficiently for this technique to work?
2. Do you think this technique would work on outside corners, including those where a fairly tight radius would be required?

Masonite and outside corners

I think you could get a scrap of Masonite and see how well the staples work before trying it on the real thing.

I don't think it would work well at all on an outside corner. The flexation of the styrene will tend to pull it away from the spackle embankments and lift it off the staple shanks.

Cheers,

Charlie

Expansion and Contraction

Charley, I too have used 1/8" Masonite for my coved corners, used liquid nails, screws and spackled the joint with the adjacent drywall with plastic webbed joint tape and drywall compound.  The wood based Masonite is a fairly similar material to the drywall and therefore has not cracked over the years.  I am surprised that the styrene does not crack at the drywall joint as the materials are so different.  Being a building contractor, I know how much vinyl siding expands and moves compared to wood siding and I guess I am comparing the materials to that.

Where did you find such large sheets of styrene and how were they shipped to you without breaking?

Love those South Jackson Railway pictures and articles, keep them coming!

Plastics supplier

I'm not Charlie, but I hope you don't mind me jumping in.  I bought a 4'x8' sheet of 0.040" styrene from a local (Omaha) plastics supplier for around $24 and just picked it up.  It easily rolled up to fit in the back of our Explorer.  If you check around your neck of the woods, you may find something similar nearby.  Otherwise, many suppliers do mail order.  In his road tutorial at  http://www.lancemindheim.com/roads.htm , Lance Mindheim recommends Piedmont Plastics as one example of the latter.

What I bought here seems to be on par with Evergreen styrene for quality, but far cheaper.  I thought one sheet would be enough to scratchbuild all the roads and structures for the entire layout, but the roads really chewed through it quickly.  I might have to go back after a 2'x4' sheet for the remaining structures.

Hi Jim,

I needed smaller radii than I felt comfortable forcing 1/8" masonite down to. Plus I'd heard a lot about masonite expanding/contracting at different rates than a lot of other materials making cracks in the joints. It appears you've solved all those issues.

I think the things that keep the joints from cracking with my coving are:

leaving the styrene unsupported in the corner. This lets it bow in or out -- in other words it can "breathe" -- when the inevitable expansion contraction occurs.

The styrene/spackle joint is always in compression.

I got my 4x8 sheets from Laird plastics in Portland. They're a wholesaler but I walked in the door and asked for 2 sheets of white, 4x8, .040" styrene and they sold them to me for cash. I rolled them up, put a bungee cord around them and stuck 'em in the back of my subaru legacy wagon and drove them home. I still have enough left to do one more (the final) coved corner and build a bunch of buildings or bridge abutments or whatever. In 4x8 sheets the stuff is a LOT cheaper than buying evergreen styrene at the LHS.

Cheers,

Charlie

Local plastic supplier

I will have to look around my area here in NE Pennsylvania to see if there is a local plastic supplier rather than pay for mail order.  Yes, I kitbash and scratch build many structures so the plastic will come in very handy.  Wonderful stuff to work with.

Thanks,

Better? choice

Before you go to this trouble, check your local building trades supply.  I was able to get drywall cove corner bead in 3" radius inside & outside.  It was metal with paper back & went on just like regular corner bead.  I was even able to flex it to fit over some 45 angles.  For the larger radii you would still need to use styrene but this makes small radii easy.

coved corners

First, I really enjoyed your telling how you did your coving. I've been thinking of doing it on my layout but didn't have any good ideas about how to do it.

One question: How do you keep from driving the staples all the way in? Maby a spacer under your stapler?

Staples?

Trainman,

Driving the staples all the way in isn't a problem, at least it's not with my stapler. It's an old Bostich, and maybe it's not as powerful as some, but the staples don't dimple the styrene - the heads are about 1/32" above the surface.

Glad you found the column useful.

Charlie