Trains.com

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Lightweight drywall joint compound for roads

11674 views
17 replies
1 rating 2 rating 3 rating 4 rating 5 rating
  • Member since
    January 2011
  • From: Horsham, Pennsylvania
  • 412 posts
Lightweight drywall joint compound for roads
Posted by woodman on Monday, April 7, 2014 1:11 PM

Has anyone ever used drywall joint compound for making roads. I just used some of WS Smooth-it for forming a road and I am not  that happy with mess and clean up required, the results were less that I expected. I have used lightweight joint compound for many things on my layout, but never thought of using it for roard until now. Anyone who has experience in this, I would greatly appreciate your input. Thank You.

  • Member since
    January 2010
  • From: Chi-Town
  • 7,706 posts
Posted by zstripe on Monday, April 7, 2014 1:34 PM

Well, if you used joint compound for many things on your layout, then you should already know that, if put on too thick, when it drys, it shrinks and will crack, creating crack patchs, which might not be too bad for a older patched concrete road. At least you won't have to add cracks, when weathering. Experiment.

Frank

  • Member since
    March 2012
  • From: Stow, OH - originally Boston
  • 177 posts
Posted by Paul D on Monday, April 7, 2014 3:18 PM

Really glad you asked this question! I've always wondered why experienced modelers pay twelve bucks for a half gallon of Hydrocal when you can get a 5 gallon pail of Sheetrock mud for another buck. Will be interested in the answers you get.

  • Member since
    January 2013
  • 118 posts
Posted by pirate on Monday, April 7, 2014 3:46 PM

I have and I thought it came out great.  Since it is water soluable, even after drying, you can use a sponge to smooth out any imperfections, or easily add a little more if needed.  It's easy to sand too.  For painting though, you need to use a solvent based paint, unless you are airbrushing.

  • Member since
    January 2007
  • From: Eastern Shore Virginia
  • 3,290 posts
Posted by gandydancer19 on Monday, April 7, 2014 3:51 PM

Paul D

Really glad you asked this question! I've always wondered why experienced modelers pay twelve bucks for a half gallon of Hydrocal when you can get a 5 gallon pail of Sheetrock mud for another buck. Will be interested in the answers you get.

 

Hydrocal and drywall mud are two completely different compounds.  Hydrocal will support itself when dry and is rock hard.  Water will not soften it when it has cured.  Drywall mud is for filling seams and holes and is weak.  It will also soften again with water after it is dry.  To make it stable, you have to paint it.  If applied too thick it will take forever to dry and will crack.  Drywall mud is sandable, but hydrocal is not.

As for using drywall mud for roads, it is OK for surfacing them and making them smooth, but not for building them up.

Elmer.

The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.

(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.

  • Member since
    January 2007
  • From: Eastern Shore Virginia
  • 3,290 posts
Posted by gandydancer19 on Monday, April 7, 2014 4:42 PM

pirate

 For painting though, you need to use a solvent based paint, unless you are airbrushing.

 

 
Not so.  House painters use latex.  Latex paint is acrylic, so regular craft paints will work.  I wouldn't use acrylic MRR paints though, as they are too thin.

Elmer.

The above is my opinion, from an active and experienced Model Railroader in N scale and HO since 1961.

(Modeling Freelance, Eastern US, HO scale, in 1962, with NCE DCC for locomotive control and a stand alone LocoNet for block detection and signals.) http://waynes-trains.com/ at home, and N scale at the Club.

  • Member since
    May 2011
  • 743 posts
Posted by Steven S on Monday, April 7, 2014 5:01 PM

Are you trying to modle asphalt?  Go to the thread below and scroll down to where I explained how I modeled asphalt using craft foam.

http://cs.trains.com/mrr/f/11/t/228662.aspx

 

Steve S

  • Member since
    March 2012
  • From: Stow, OH - originally Boston
  • 177 posts
Posted by Paul D on Monday, April 7, 2014 5:10 PM

Thanks for that, gandy. Clarifies a lot. Have just been thinking that a half gallon of Hydrocal will do a few roads but a 5 of mud will build half the Appalachian Trail. I'm doing a downtown scene too, and figure on having a DPW truck with asphalt patch and two laborers with shovel & rake patching potholes. Something we've all seen, though not as often as we'd like! Thanks.

  • Member since
    January 2013
  • 118 posts
Posted by pirate on Monday, April 7, 2014 8:24 PM

gandydancer19
 
pirate

 For painting though, you need to use a solvent based paint, unless you are airbrushing.

 

 

 
Not so.  House painters use latex.  Latex paint is acrylic, so regular craft paints will work.  I wouldn't use acrylic MRR paints though, as they are too thin.
 

That's true, but house paint is very thick.  I would use a thinned paint for a road, to maintain the texture, so I would at least test a water based paint first.

 http://i293.photobucket.com/albums/mm58/rschissler_bucket/IMG_0249_zps4ddb7596.jpg

PS.  Is there any reason why I can't post a picture?  There is no icon to do so.

 

 

  • Member since
    March 2005
  • From: New Brighton, MN
  • 4,393 posts
Posted by ARTHILL on Monday, April 7, 2014 8:54 PM

I use it for everything. I mix it with saw dust and acrylic paint to get my version of Ground Goop (Sassi) I fill gaps in my foam with it. I gave all my plaster away. No more clogged drains. Easy clean up . And it gives time to work. It carves great for block walls.

If you think you have it right, your standards are too low. my photos http://s12.photobucket.com/albums/a235/ARTHILL/ Art
  • Member since
    May 2010
  • From: SE. WI.
  • 8,253 posts
Posted by mbinsewi on Monday, April 7, 2014 11:36 PM

I also use drywall mud, only I buy the bag of powder, 20 minute set.  I used it for all paved areas.  You can get it in different set times.

Steve, nice work, it looks great.  I did the same with the mud.  It is soft, but easy to shape and finsih.  I primed it first, than different paint to get the look of weathered concrete, or asphalt.  If you look at my links, below, the hyway overpass, and the retaining wall is all drywall mud, along with any of the paved areas.

Mike.

  • Member since
    November 2002
  • From: US
  • 2,455 posts
Posted by wp8thsub on Tuesday, April 8, 2014 12:46 PM

gandydancer19
Drywall mud is sandable, but hydrocal is not.

Hydrocal and other setting-type plasters are indeed sandable.  For various construction applications, such as filling deep areas, setting plasters are used instead of standard drywall compunds that air dry.  Hydrocal is readily sandable in plaster structure kits too (along with casting plaster, dental stone, etc.).  For something like building a road, setting plaster may be more difficult to work with, but could also be used for the entire road and sanded for the finished surface.

Rob Spangler

  • Member since
    November 2002
  • From: US
  • 2,455 posts
Posted by wp8thsub on Tuesday, April 8, 2014 12:55 PM

Another material that can work for asphalt is sanded tile grout.  It has the advantages of being the same color all the way through, and of a long working time to eastablish the final shape.

This road was made from grout and weathered with acrylic paint.  Cracks were added using a drafting pen with waterproof ink.

Here's a closeup of some tile grout asphalt showing the variations in texture.  This is HO scale.

Rob Spangler

  • Member since
    January 2013
  • 118 posts
Posted by pirate on Tuesday, April 8, 2014 1:16 PM

I guess I have to use Chrome to post a picture:  Here are my roads with drywall joint compound:

  • Member since
    January 2010
  • From: Chi-Town
  • 7,706 posts
Posted by zstripe on Tuesday, April 8, 2014 2:35 PM

Pirate,

Nice job and scene! Yes

Rob Spangler,

You did a great job, of the blending of the backdrop and road. Bow

Frank

  • Member since
    September 2010
  • From: Redmond, Wa.
  • 171 posts
Posted by glutrain on Wednesday, April 9, 2014 12:23 AM

I tried a lot of different road building techniques off layout before opting for the WS Smooth-it as road base.When I used the Smooth-it, I used milk carton stock to make the equivalent of concrete forms and built most of the roads up with several thin pourings. Air bubbles whipped in as the Smooth-it was mixed tended to become natural potholes- the ones I liked, I kept-the others were sanded out and covered with the next pouring. When the roads had the desired shape, I sealed the smooth-it with a coating of my ballast mix adhesive and painted it with craft store acrylic paints. What I learned was that I was talented enough to make a mess out of any given technique. Off layout practice is worth a try on something like this that gives so much character to a layout.

Don H.

 

  • Member since
    April 2014
  • 23 posts
Posted by semafore on Wednesday, April 9, 2014 1:00 PM

Hi everyone. Newbie Semafore here. I am intrigued with this topic, and I am amazed at the photos of model asphalt. I wish to achieve such deep detail myself. Thank you fo r raising the discussion.

Subscriber & Member Login

Login, or register today to interact in our online community, comment on articles, receive our newsletter, manage your account online and more!

Users Online

Search the Community

ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT
Model Railroader Newsletter See all
Sign up for our FREE e-newsletter and get model railroad news in your inbox!