www.TK560.com Forum Index www.TK560.com
Vacuum Forming, Movie Prop, Sci-fi and GIjOE Forum
 
Log in to check your private messagesLog in to check your private messages

Log inLog in  RegisterRegister


Profile  Search  Memberlist  FAQ  Usergroups
Alternative to Bondo...

 
Post new topic   Reply to topic    www.TK560.com Forum Index -> Imperial-Armor.Com Q&A
View previous topic :: View next topic  
Author Message
badger
Novice


Joined: 03 Sep 2006
Posts: 63

PostPosted: Sat Jan 27, 2007 1:29 am    Post subject: Alternative to Bondo... Reply with quote

Tonight I messed around with an alternative to Bondo.


Durhams Rock Hard Water Putty.

I've been curious about it since I read about it in the TJ book. I had a can sitting around waiting for a reason to try it out. I am working on a new mold for a Tusken Raider mask, and I had built up a base in wood, and needed to do some shaping a la Bondo.

So far I am VERY impressed with this stuff. The first application dried in about 2 hours, and was like it's name says rock hard in the thick spots, but it's still easy to sand about the same as Bondo. Thin spots (just like bondo) are a bit fragile, but this is really a filler not a platiscine clay. After my first pull I put some more on to fill in areas, and get rid of some under cuts. It's very easy to mix, it's a powder, that you just add some water too and stir. Good working time, and best of all... DOES NOT STINK LIKE BONDO! God, I hate the smell of Bondo. In the winter I have to leave the mold in the garage, and the smell seeps into the entire house. Durhams? Not much smell at all.
Back to top
View user's profile Send private message
drcrash
Guru


Joined: 04 Sep 2006
Posts: 705
Location: Austin, Texas

PostPosted: Sat Jan 27, 2007 3:23 am    Post subject: Re: Alternative to Bondo... Reply with quote

Water putty is cool. (The off-brand stuff is just as good as Durham's---it's a very standardized repair product.)

It will get considerably harder and stronger over the next day or two.

One of the nice things about water putty is that you can tool it for a while, and when you're happy with it, set it aside and let it harden up more. It doesn't fully set up and become brittle right away. (And it's never really "brittle" even when it's hard. It's a little tougher than a lot of plasters.)

I usually reinforce it with drywall tape. (The 1/8" yellow fiberglass mesh stuff in rolls at the hardware store.)

I also ran into Durham's on a model rocketry site (aeroconsystems.com) when I was looking for cheap straight nichrome.

Turns out rocketers use it to make rocket motor nozzles. I guess it can take a lot of heat, at least for a little while. I wonder if it would make a good refractory.

BTW, water putty expands ever so slightly when it sets up. That is useful for its normal uses, because it wedges itself into gaps you fill with it, and won't fall out. It's also useful when making concave molds---it helps you get the mold off the positive. But when casting it into a negative mold, it makes it a little harder to get out.

It also sticks to itself well, so you can abrade some off to shape things, and if you took too much off, put some fresh stuff on and it will be okay.

You can color it all kinds of colors by mixing in inexpensive acrylic craft paint, too.

Water putty isn't expensive---$6 for a 4-lb canister at the hardware store.

You can mix water putty and plaster of paris to get something that's substantially stronger than plaster of paris, and pretty cheap.

I cast water putty in a plaster life cast to make this:



(The lighter-colored parts are where I smeared thin fresh water putty to smooth it out. It wasn't a great plaster cast job.)

Then I made this three-piece mold out of 1/3 water putty and 2/3 plaster of Paris:



Here's the original (fully dry, and shellacked) and a water putty copy made in the mold:



(The mold marks haven't been tooled away yet in the picture.)

If you want to see the mold-making sequence, check out this photobucket album:

http://s136.photobucket.com/albums/q176/drcrashpix/miscmolding/torso/

The pictures are in pretty much reverse order, sorry.

Paul
_________________
Paul (a.k.a. Dr. Crash)

Tired of buying cheap plastic crap? Now you can make your own! www.VacuumFormerPlans.com
Back to top
View user's profile Send private message Visit poster's website
badger
Novice


Joined: 03 Sep 2006
Posts: 63

PostPosted: Sat Jan 27, 2007 4:54 pm    Post subject: Reply with quote

The more I use this stuff, the happier I get.

I put a (hopefully) final coat on today, to smooth it out, and get rid of some under cuts. On a whim I did final smoothing with wet fingers. Worked GREAT! It had gotten mostly stiff by this point, and a light wetting of the fingers (with rubber gloves on) I was able to smooth it out quite nicely.

Pictures of the mold, after I had applied the putty, smoothed it, and dried for about 1/2 hour. This is pre sanding.

http://www.badger.cx/coppermine/albums/userpics/10001/TuskenMoldPutty1_md.jpg
http://www.badger.cx/coppermine/albums/userpics/10001/TuskenMoldPutty2_md.jpg
http://www.badger.cx/coppermine/albums/userpics/10001/TuskenMoldPutty3_md.jpg
http://www.badger.cx/coppermine/albums/userpics/10001/TuskenMoldPutty4_md.jpg
http://www.badger.cx/coppermine/albums/userpics/10001/TuskenMoldPutty5_md.jpg
Back to top
View user's profile Send private message
jegner
Site Admin


Joined: 30 May 2003
Posts: 2092
Location: Texas, USA

PostPosted: Sat Jan 27, 2007 8:02 pm    Post subject: Reply with quote

Badger,

That Tuskin Radier mask project looks like it's gong to be a fun one. I was thinking about doing the same thing, vacuum forming a rigid 2 part mask instead of the latex soft mask that 'Godzilla' makes.

One of these days, I'll get started on that one. LOL.

As for the water putty, I have used that stuff, and I like it too. Usually, I'm in too big a rush to wait for it to dry, and I end up using Bondo, just for the speed, but sometimes, the water putty works better.

Jim
Back to top
View user's profile Send private message Send e-mail Visit poster's website AIM Address
tubachris85x
Master


Joined: 15 Jan 2007
Posts: 351
Location: Ft. Lauderdale, Florida

PostPosted: Fri Feb 16, 2007 6:23 am    Post subject: Reply with quote

Yea, this stuff is amazing. I have been using this countless times. The only issue I am having though is when filling some gaps, its a pain to level it evenly. When I go to sand it, I find that it may leave so smaller un-leveled areas which I then have to go back and fill.

-tubachris
_________________
Back to top
View user's profile Send private message AIM Address MSN Messenger
Display posts from previous:   
Post new topic   Reply to topic    www.TK560.com Forum Index -> Imperial-Armor.Com Q&A All times are GMT - 6 Hours
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

phpBB "skin" by DewChugr


Powered by phpBB © 2001, 2005 phpBB Group