After using plaster bandage for my hard-shell, I decided that it was a
little flimsy so I wanted to brush on a coat of Hydrocal to strengthen it
and add texture. I mixed up a batch of Woodland Scenics "Lightweight
Hydrocal", wet down an area and attempted to brush the plaster on. What
happened was that the plaster gummed up the paintbrush and came off in
little balls onto the layout, not what I expected at all. The plaster
didn't seem thin enough, so I mixed up another batch, adding more water.
This seemed to apply better, but when it dried, just touching it turned it
into powder. Is there a better material than Woodland Scenics Lightweight
Hydrocal for brushing on texture and strength over plaster mesh hard-shell?
Thanks in advance for your help. This group has been very helpful to me
with two other questions I've had in the last couple of weeks.
Paul B.
: After using plaster bandage for my hard-shell, I decided that it was a
: little flimsy so I wanted to brush on a coat of Hydrocal to strengthen it
: and add texture. I mixed up a batch of Woodland Scenics "Lightweight
: Hydrocal", wet down an area and attempted to brush the plaster on. What
: happened was that the plaster gummed up the paintbrush and came off in
: little balls onto the layout, not what I expected at all. The plaster
: didn't seem thin enough, so I mixed up another batch, adding more water.
: This seemed to apply better, but when it dried, just touching it turned it
: into powder. Is there a better material than Woodland Scenics Lightweight
: Hydrocal for brushing on texture and strength over plaster mesh
hard-shell?
: Thanks in advance for your help. This group has been very helpful to me
: with two other questions I've had in the last couple of weeks.
: Paul B.
Paul,
Maybe the plaster bandage is soaking up the water from the new plaster. Try
dampening the old plaster thoroughly before brushing on the new stuff.
Actually, I did wet down the area first. Perhaps there's something about
Woodland Scenics Lightweight Hydrocal that doesn't handle brushing well?
Maybe a different product would perform better? After mixing the batch
according to the instructions, its consistency didn't seem very "brushable"
to me.
Paul B.
hard-shell?
Paul, I have never used the Woodland Scenics product. I have a small hobby
budget and want to get the most for my money, so I use "Plaster of Paris", I
mix it up to a consistency of pancake batter and use a small putty knife or
small trowel to put it on the cardboard shell. I try and do most of the POP
work BEFORE I fix the track in place. it is OK if the POP gets on the cork,
I just wipe it off. It is harder to clean POP from N Scale track.
"brushable"
That might be the key Paul.
One of the old model RR fellows at the club always carries s set of small
paint brushes and a couple of small trowels and putty knives. The former is
used for paint while the later is used for plaster. He says you "gotta use
the right tool for the right job."
You have described old hydrocal. It does not have a good shelf life and
those WS boxes sit in hobby shops for years. Mix up some and just pour it
out onto wax paper. If it doesn't set up thin and very hard, toss it. If
you can't get real hydrocal, use plaster of Paris or molding plaster.
You'll just have to do a thicker coat.
By "wet down" do you mean until the under layer won't absorb anymore water?
Not damp, not misted, but thoroughly - dripping wet.
CTucker
NY
I agree with Don. A freind of mine works for a lumber yard
and last year visited a gypsum plat in GA. he was told that
plaster is mixed for different humidities indifferent parts of
the country and different seasons of the year.
We (at our club) have been successful brushing on plaster
(even though a spatula or putty knike works better) if we
mix it really thin with a capful of yellow glue and work fast.
It does become very hard when completely dry and setup.
We mix it to the consistcancey of pancake batter and use this
method to hide the edges of the hardshell's paper strips and
joining rock molds to the hardshell. A ten lb. bag at a lumber yard
is around only $15 bucks or so IIRCaand goes a long way.
Ron.
I have used Durobond's Webpatch 90 over plaster bandage and aluminum screen
mesh. I didn't wet the plaster bandage, just the joints to seal them, then I
made up a slurry of the Webpatch and used a very flexible spatula to smooth
everything. Once dry, it took 24-48 hours, it was rock solid. I got the
Webpatch 90 at Lowe's (a home improvement store).
Jeff Hensley
Sugar Creek RR
Greenfield,IN
Durabond is available in 90 minute 45 minute and
20 minute. If you can not find Durabond look for
EasySand 90, 60 or 20.
It is found in the drywall section. It is a product
made for patching draywall but it is much harder then
drywall compound and it will not shrink and crack.
I have used it for rock molds, and hardshell scenery
and it is rock hard. It will not turn back to joint
compound if you rewet it like the ready mix compounds
do.
> I have used Durobond's Webpatch 90 over plaster bandage and aluminum
> screen mesh. I didn't wet the plaster bandage, just the joints to seal
> them, then I made up a slurry of the Webpatch and used a very flexible
> spatula to smooth everything. Once dry, it took 24-48 hours, it was rock
> solid. I got the Webpatch 90 at Lowe's (a home improvement store).
Actually the last bag of Plaster of Paris I bought at Menard's (like home
depot or Lowe's, throught the upper midwest) was 25 pounds for around
$10.00.
Don
--
snipped-for-privacy@prodigy.net
How far from the border are you? Back in the 60's we used to make "oleo
runs" to Illinois because Wisconsin had a high tax on colored margarine,
making it more expensive than butter.
I can see people smuggling big bags of "white powder" across the border .
Don
--
snipped-for-privacy@prodigy.net
Try finding a Stucco supply yard. Hydrocal White - 40 lb bag for $10 us.
Beats the 2 lb milk carton for $7.
If its powdery I say you don't have enough water. I just pour out of the
mixing cup and as it sets up "play with it" a bit to roughen it up.
hard-shell?
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