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hydrocal vs scupltamold??

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hydrocal vs scupltamold??
Posted by ksteppe on Thursday, January 10, 2013 6:49 PM

What is the best use for each of these products?  For what application is one prefered over the other?

Thanks,

Kent

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Posted by MisterBeasley on Thursday, January 10, 2013 7:23 PM

Hydrocal is a fine-grained plaster used for castings.  You mix it up and pour it into a mold, and when it hardens you've got a stone wall or a cliff face.

Sculptamold is more of a surface cover, used for creating terrain by spreading it over a surface free-form, building up small outcroppings.  It's similar in that respect to Gypsolite, a much grittier plaster that I find makes a nice uneven surface to simulate ground.

It takes an iron man to play with a toy iron horse. 

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Posted by NP2626 on Thursday, January 10, 2013 8:41 PM

Hydrocal is also used by dipping paper towels into it as a method of building a scenic surface.  It can be used in lieu of the plaster cloth which is so popular now.  It can be mixed with other materials to build up it's thickness and delay setting and then carved into rock faces.  Scultamold is great stuff, I use it over plaster dipped paper towels; or the plaster cloth material I just mentioned and even right on top of the layout plywood to make undulating surfaces and carve rock faces in.  The photo below shows a gulch area I built with Cardboard strip lattes work, covered with plaster cloth which in turn was covered with sculptamold that was then carved into the layered rock face.

NP 2626 "Northern Pacific, really terrific"

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Posted by caldreamer on Thursday, January 10, 2013 9:04 PM

Hydrocal is harder than Sculptamold and is less expensive.  It can be purchased in 50 or 100 Lb bags.  Both are good products.

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Posted by LNEFAN on Thursday, January 10, 2013 10:39 PM

I just completed certain areas of my layout using Sculptamold and found it to be very easy to work with in creating terrain. I also used it in a "goop" mix with white glue, vermiculite and latex paint with great success. 

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Posted by MisterBeasley on Friday, January 11, 2013 8:11 AM

gsrrman
It can be purchased in 50 or 100 Lb bags.

Be aware, though, that Hydrocal has a finite shelf life.  I buy mine in 10-pound containers from Scenic Express.  By the time I work my way down to the bottom of the container, the castings get weak and crumbly.  I suspect that, even though I keep the container sealed, the Hydrocal absorbs moisture and goes bad.  I am talking about a time scale of at least a couple of years, though, so if you're using it for hardshell and going through a lot, then you may be OK.

Buying a big bag of the stuff will give you a good price per pound, but if you end up having to throw a lot of it away, you may not be saving as much as you think.

It takes an iron man to play with a toy iron horse. 

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Posted by caldreamer on Friday, January 11, 2013 8:54 AM

I checked last night and Home Depot has it for $15.98 for a 50 pound bag.  Even if you have to throw some out, it is still very inexpensive.  ;My layout is quite larege 39 X 12.5 Feet so a large quantity will work for me.

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Posted by twhite on Friday, January 11, 2013 2:27 PM

I've used both and like them both a lot.  My only one problem with Hydrocal is that I have an uninsulated garage layout in a dry climate, so depending on both humidity and temperature, I have to be careful about when I use it, as it occasionally sets up WAY too fast to work with successfully.  I don't have that problem with Sculptamold, which has a much longer 'working' time. 

Sculptamold can be used in rock castings if you're patient and increase the water quotient when you're mixing it (directions on the package).  The additional moisture allows the plaster part of the mixture to 'settle' down into the rock mold.  I've used it pretty successfully that way, though the mixture does take about 20 minutes or so to set up strong enough to place the casting and remove the mold. 

But I like both a lot.  I tend to find Sculptamold a little more versatile for my needs.

Tom

 

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Posted by caldreamer on Friday, January 11, 2013 2:43 PM

Hydrocal does set up quickly.  What I do is add a little extra water to make it thinner,  That increases the setup time by about 5 minutes.  I also have used both in rock molds and they work equally well.

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Posted by yankee flyer on Friday, January 11, 2013 6:51 PM

gsrrman

Hydrocal does set up quickly.  What I do is add a little extra water to make it thinner,  That increases the setup time by about 5 minutes.  I also have used both in rock molds and they work equally well.

I didn't see mentioned, that Sculpt-mold Is lighter and easier to cut or grind. I believe it has ground up paper or something in it. I use it for almost everything. It can give rock castings a little rougher texture.

Enjoy

Lee

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Posted by Jaddie on Friday, January 11, 2013 7:06 PM

Dear Kent & Friends

Dave Frary says Sculptamold is his favorite modeling compound.

A 25-pound box of Sculptamold was available on Amazon the other day for US$50 including shipping.

It has a nice texture, but its working time isn't as long for me as Dave Frary says it is for him--30-40 minutes. It's more like 15-20 minutes for me, though I'm probably not mixing it correctly.

UPDATE: I was completely incorrect when I said Dave Frary claimed 35-40 minutes of working time with Sculptamold. I just watched his Easy Scenery DVD for at least the 50th time and he claims 20 minutes of working time. I apologize for my error.

--Jaddie

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Posted by NP2626 on Saturday, January 12, 2013 7:37 AM

I've always been able to work Sculptamold for 30-40 minutes.  The amount of water added doesn't seem to effect cure time for me, either.

Sculptamold is my favorite scenic material, also.

NP 2626 "Northern Pacific, really terrific"

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Posted by HHPATH56 on Saturday, January 12, 2013 8:23 AM
I use both Sculptamold and Hydrocaal. For river bottoms and where there will be a lot of rough handling, I use Hydrocal. For sculpting distant mountains I use sculptmold. Hydrocal is waterproof, so is preferable where plastic "water" will be poured. Sculptamold will flake off if handled roughly. Both are great. Bob Hahn
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Posted by Jaddie on Saturday, January 12, 2013 9:51 PM

Dear Bob

In the next two to three weeks I plan to do the last big thing to my son's model railroad--pour Realistic Water into his pond. Its base is now covered in Sculptamold.

Is it okay to pour the Realistic Water on top of the Sculptamold, or should I put on a layer of Hydrocal over the top of the Sculptamold?

--Jaddie

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Posted by cacole on Sunday, January 13, 2013 7:46 AM

White vinegar added to plaster will retard its setting time, but I have never read exactly what percentage of vinegar should be added.

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Posted by bogp40 on Sunday, January 13, 2013 8:14 AM

If you buy Hydrocal in large quantities and want to extend the working properties/ shelf life, repackage about 1/2 coffee can amount into plastic sandwich bags. I will place these in a sealable 5 gallon bucket.  You can grab as many "packs" as needed for your project. Much neater (not digging into a bag and continually contaminating the lot)  Lessens any powdery mess and will allow the remaining Hydrocal to last up to a year and then some pending your enviornment.

Modeling B&O- Chessie  Bob K.  www.ssmrc.org

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Posted by CTValleyRR on Sunday, January 13, 2013 10:47 PM
Jaddie --

I use Sculptamold just about everywhere on my layout. Including underneath water products. Never had a problem (although I don't put the water on raw Sculptamold--I paint it with latex paint first).

Connecticut Valley Railroad A Branch of the New York, New Haven, and Hartford

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Posted by Metro Red Line on Thursday, January 17, 2013 2:30 AM

MisterBeasley

gsrrman
It can be purchased in 50 or 100 Lb bags.

Be aware, though, that Hydrocal has a finite shelf life. 

Hydrocal can last forever if you keep it in an airtight container in a cool, dry place.

I bought a bag of Hydrocal from a hobby shop in 1993 and still had a bunch left over. I kept it in a ziploc freezer bag with the excess air squeezed out and stored it in a shoebox under other boxes in my layout. Years later, when it came to build another layout, I used the same bag to make some retaining wall castings...no clumps, worked perfectly fine in 2010 - 17 years later!

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Posted by Metro Red Line on Thursday, January 17, 2013 2:34 AM

bogp40

If you buy Hydrocal in large quantities and want to extend the working properties/ shelf life, repackage about 1/2 coffee can amount into plastic sandwich bags. I will place these in a sealable 5 gallon bucket.  You can grab as many "packs" as needed for your project. Much neater (not digging into a bag and continually contaminating the lot)  Lessens any powdery mess and will allow the remaining Hydrocal to last up to a year and then some pending your enviornment.

Make sure they're ziploc bags and use the thick kind intended for freezer use. Pack the Hyrocal DENSELY, with no loose grains tumbling around, and squeeze the remaining air out as you seal the bag. Keep in a cool, dry, dark place. My supply of Hydrocal has lasted me almost 20 years!

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Posted by MisterBeasley on Thursday, January 17, 2013 6:57 AM

cacole

White vinegar added to plaster will retard its setting time, but I have never read exactly what percentage of vinegar should be added.

Red wine vinegar will also retard setting time.  However, your train room will smell like a salad bar for a week or so.  Don't bother to ask how I know this.

It takes an iron man to play with a toy iron horse. 

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Posted by Metro Red Line on Thursday, January 17, 2013 7:04 PM

MisterBeasley

Red wine vinegar will also retard setting time.  However, your train room will smell like a salad bar for a week or so.  Don't bother to ask how I know this.

The Vinaigrette & Southern!

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