Day one

I start with a piece of foam board, in this case 300 x 200 mm (12" x 8") big. I use 5 mm thick foam board that I buy from http://www.foamboardsource.com/. The vertical line is the center line of the tunnel portal, the horizontal line is the height of the rail head.

As I'm building a German tunnel portal I use NEM 105 as the correct standard for the tunnel dimensions. This tunnel is part of my main line so I need a double track sized portal.

I start by drawing the tunnel opening and then adding lines representing the large blocks that line the portal. The cover paper is easy to pull off.

With a new blade I carefully cut along both lines trying not to cut deeper than about half the foam thickness.

I then start engraving the blocks using a 0.5mm pencil. 

I like the different shapes old European tunnel portals had. I have seen one similar to this but I don't remember where. Doesn't matter as long as it looks good!

I peel off the cover paper again...

...then carefully cut along the outer line...

...and then along the inner line.

With the back of my knife blade I engrave the outer...

...and inner mortar lines of the blocks.

This is how it looks so far.

According to the time stamps on the pictures It took all of 37 minutes to do this. To be continued tomorrow!

Another neat project

Very nice Michael.

These are the kind of projects I like seeing here on the forum.

Bernd

thks

Neat!

Michael,

What a neat way to make tunnel portals! Wish I would have thought of that. I've just finished casting about 15 tunnel portals out of plaster with a homemade mold. It worked, but your way sure would have been faster with a lot less mess. Next time around, I'll be doing it your way. Thanks for the great tip!

Paul Krentz

N&W Pokey District, Sub 1 3/4

Day two

Thanks everybody for your kind replies. Let's hope you like what's coming as well...

The next step is engraving the mortar lines in the portal wall. Here is the result:

Now the real fun begins: gluing the strip I cut out yesterday. I use hot glue for this with my glue gun on the low heat setting. I position the piece where it should go and fill up the corner with hot glue.

I carefully work all the way around.

This is the result so far:

I cut a 10 mm wide strip of 3 mm thick foam board which is a really flexible material. The strip must be long enough to go all the way around the portal opening. Using hot glue again I glue this strip to the inside of the portal opening.

Using the back of my knife I then carve the mortar lines.

At this point I decided that the portal wall looked too boring so I cut off two strips on the left and the right. These strips I then moved out a bit to give the wall more structure.

As you can see in the next picture there are visible gaps between the parts because the joints are not perfect.

To fill these I use spackling, the kind that goes on pink and dries white.

I use really small amounts that I dilute with lots of water.

I work it into the gaps with an old stiff brush.

Now the portal looks like this:

That's it for today, I'll let this completely dry over night.

Very nice

Very nice clear pictures. They tell the procedure well.

Bernd

Amazing!

Some really great "outside the box" thinking there!

George

Day three

Today I started making the tunnel liner: I cut a piece of 3 mm foam board about 12" square and then started engraving lots of blocks. I always make my tunnel liner as long as the longest passenger car. This way it looks like the tunnel keeps going straight.

The next step is rolling up the foam and letting it sit for a few hours to make it easier to shape. Because I had a deadline (this post) I only gave it 30 minutes this time and then moved on.

Starting from the center I then use hot glue again to put the tunnel mouth and the liner together.

Here is the result so far:

To finish the portal I added a cornice made out of 3 mm foam strips.

Now it's time for spackling again!

This is where the portal will later go:

portal

Michael , you are the Foam Master!

Day four

All I did today is give the portal a coat of thinned gray paint to make it look real. I will work on the final color and weathering when I install the portal. I hope you all enjoyed this little tutorial. I certainly did!

Beautiful work Michael!

Beautiful work Michael!

THis thread just goes to show

that you can have some really well done model railroad items without much dollar cost (just time investment).  Thanks Michael - nice portal and technique.

Really Cool Michael

Would have never even thought of using foamboard to model something like a tunnel portal. Very neat way to build a custom portal. Thanks for sharing!

Cut Stone Portal and tunnel liner

Very Nice!!

paper on form board

Can you tell me how you made it  look so easy to peel the outer paper off as mine comes off in little bits and looks really terrible and uneven.

Gordon

Re: paper on foam board

I have made similar models and portals using this technique. The trick is in buying the cheapest foam board, so the paper comes off very easily and in one piece.

I have found that the foam board sold in Dollar Store usually is easy to peel off the paper backing than the expensive ones sold at Michael's, Wal-Mart or Hobby Lobby.

Also the foam is much flexible to roll or carve and you can simply glue multiple layers to build a 3D model.

Great work by  michaelrose55 and is very impressive.

ICETRAINS

Great!

That tunnel looks great!  Thanks for posting and taking your time to explain how you did it.

D.A. 

Thanks...

Great work Michael!  Thanks for the photos and explanation, outstanding scratch building, from a piece of foam board to a custom tunnel portal... Wow!

James

I'm glad everybody still

I'm glad everybody still likes what I did over a year ago. It's funny how sometimes old threads come back to live!

Can you tell me how you made

Dollar Tree stores have a product called Readi-Board.  While you're at the store, go to the cleaning supplies and buy a bottle of LAs Totally Awesome Cleaner.  Spray it on the Readi-Board, let it soak in for a minute and then peel off the outer paper.  The foam has a smoother texture than the stuff that Michael used.  If you want it to look more like rough stone, look for some Depron foam at your LHS.

Steve S

I still buy my foam board at

I still buy my foam board at this website: http://www.foamboardsource.com and the paper comes off easy.

Speachless

You are an artist. Being a foam person  I understand the time and effort that you put into this project. Thanks for sharing in detail.

Beautiful Foam Board Detail carving for Tunnel Portals

That is Superb Modeling Shaun. Thank you for sharing  your talents with us, I really am impressed with your detail work and the tunnel liner is fantastic. I may copy some of your work as I had not ever considered foam board for this purpose. I have always used plaster.