A Crafts Community For Craft Ideas & DIY Projects - Craftster.org
Help | About | Contact | Press | Advertise | Terms | Site Map
Welcome, Guest.
Please login or register.
Random Tip: You can now organize your bookmarks into folders!  Read more here.
Total Members: 302,093
Currently Running With Scissors:
600 Guests and 26 Users
Home Craftster Community Crafting Articles Craft Tutorials My Craftster Crafting Calendar City Guides Craft Shop


Pages: 1 ... 162 163 [164] 165 166 ... 172
Jump to page:
  Show Images Only     Send this topic  |  Print  |  Bookmark  
Topic: The random RESIN question thread!  (Read 302675 times)
Tags for this thread: resin , mold , catalyst , resin_problems  Add new tag
Share the love... Pin it Submit to reddit add to Wists
1+
 
Diane B.
Offline Offline

Posts: 5062
Joined: 01-May-2004

GlassAttic --polymer clay "encyclopedia"


View Profile WWW
« Reply #1630 on: December 25, 2010 08:31:06 AM »

I seem to remember that I answered the first part of your question somewhere else (do you use YahooAnswers maybe?).  But the bubbles part is something different. 
Bubbles are normal when using resins though you can keep them down in a few ways, like being sure the resin isn't too cool**, pouring it slowly, kind of folding/whipping when mixing the parts rather then just stirring vigorously in any and all directions (though some resins will get bubbles less easily), not putting anything into the resin that isn't sealed if it's porous or has any little crevices in and around it that can trap air, etc.

** for best results make sure the temp is between 68° and 80° F, and that the humidity is below 50% for the pour and the cure

Most "normal" bubbles will pop on their own as they rise from the heat generated by the chemical reaction that makes resins cure, but you can use any kind of carbon dioxide too: blow through a straw but don't INhale, pass a lighted match or torch around and around near the surface but keep it moving, use a heat gun though a hair dryer will stir up a lot of dust (and for the same reason stay away from the fan), etc.

You can read more about bubbles, mixing, types of resin, sealing when necessary, etc, also on this page at my site, if you're interested in more details:
http://glassattic.com/polymer/other_materials.htm

HTH,
Diane B.
« Last Edit: December 25, 2010 08:36:29 AM by Diane B. » THIS ROCKS   Logged

POLYMER CLAY "ENCYCLOPEDIA" 
http://glassattic.com/polymer/contents.htm
few of my photos
http://s96.photobucket.com/albums/l163/DianeBB
(had to move them from YahooPhotos, so many now without captions)
amaliadc
« Reply #1631 on: December 25, 2010 09:28:52 AM »

Thanks Diane - I did post on Y!A hoping to get fast answers Smiley

I didn't have any bubble issues in the end - but the coasters didn't turn out very well. Not sure if it was the mold, or my own errors, but they were impossible to get out (I froze them for a bit and then wacked them with the end of a screwdriver.) Either they weren't cured enough or I don't know, again I'm new at this. They finally popped out - but cracked. Did I do it too hard, too much catalyst....?

The bottom of the mold had some resin still in it, so the tops of the coasters came out very lumpy and uneven and not glassy at all.


Maybe I was just too impatient. I ordered the right type of mold online anyway, hopefully that'll give me better results.


I should add I used Pam as the release agent.
« Last Edit: December 25, 2010 09:37:31 AM by amaliadc » THIS ROCKS   Logged
Diane B.
Offline Offline

Posts: 5062
Joined: 01-May-2004

GlassAttic --polymer clay "encyclopedia"


View Profile WWW
« Reply #1632 on: December 25, 2010 09:43:20 AM »

How long did you leave them before trying to remove?

Did you ever say which *kind* of resin you used (or do you at least have the brand name, or can say whether you mixed the parts one to one, or a few drops of one to a lot of the other?).

Diane B.
THIS ROCKS   Logged

POLYMER CLAY "ENCYCLOPEDIA" 
http://glassattic.com/polymer/contents.htm
few of my photos
http://s96.photobucket.com/albums/l163/DianeBB
(had to move them from YahooPhotos, so many now without captions)
amaliadc
« Reply #1633 on: December 25, 2010 09:51:26 AM »

I left them for 24 hours. Thinking perhaps I should have left them longer. I assumed they were about ready, because it looked like they were separating from the mold.

I bought Castin Craft poly resin. I used an ounce per layer, 5 drops of catalyst for the first and 4 drops for the second layer.

I attached a photo. You can see were they cracked, and on the first coaster you can see a weird residue and such on the top.

http://i7.photobucket.com/albums/y282/ImAmaliaBedelia/photo6.jpg

They're also a bit sticky on both sides.

« Last Edit: December 25, 2010 09:54:28 AM by amaliadc » THIS ROCKS   Logged
Diane B.
Offline Offline

Posts: 5062
Joined: 01-May-2004

GlassAttic --polymer clay "encyclopedia"


View Profile WWW
« Reply #1634 on: December 25, 2010 10:29:12 AM »

Okay, so what you used was the "polyester" type of clear arts & crafts resin...the main brand of that is still Castin Craft Clear Polyester Casting Resin (a mouthful).  On the other hand there are many brands, and even some types, of epoxy resin.

Polyester resins have some advantages and some disadvantages compared to epoxy resins though...for example, they:
...are less safe for lungs/breathing, and stinky
...are less strong after curing (more brittle)
...will not thoroughly cure in the presence of air (so the side curing next to air may be or stay sticky, or be ripply, etc)
...will become rubbery if ever subjected to temperatures over 200F later
...are very fiddly for getting the right proportion of catalyst to resin to each project (see below)
The advantages are that it can be poured deeper than 1/4-1/2" and so make "taller" casts than regular epoxy resins, are a bit cheaper, and often will be less subject to later yellowing from UV light (if not sealed with UV-resistant polyurethane, etc).  Regular epoxy resins should only be used at those thinner pour depths or shallower** (they're also used as "coatings," applied with brushes or dipped, etc).  

**There are tweaked epoxy resins though at least that can be cast deeply, like Easy Cast.  Easy Cast will get a softer surface though if exposed to (even body) heat, and if thin can be flexible.

Here are a couple of things from the page at my site I gave you before about cracking in polyester resins:
.....Too much catalyst makes resin set faster, but also creates too much heat; this can lead to fracturing of resin, or fading of embedments or distortion of vinyl-based or styrene-based plastic molds.
...and similarly, with some overlap:...because heat accelerates chemical reactions, all resins cure from the INSIDE out...using too much catalyst will overheat the casting (excessive exotherm), causing resin shrinkage and cracking, and discoloration ...but exotherm can be controlled by adjusting the amount of catalyst used, the volume or thickness of resin poured (at one time), and ambient temperature (the higher the temperature, the faster the gel ...too fast a cure will cause fractures.)
...thicker (taller) pours require less catalyst because a thick casting retains heat... whereas a thin section dissipates the heat requiring more catalyst.
...If the room your'e working in is below 65 degrees F, it will slow down the curing.  If the room is over 75 degrees F, it will accelerate the curing and may cause yellowing and/or cracking.


Sometimes resins will take longer than 24 hrs before easy removal too (even in the "right" molds or with the right releases), especially due to temp and humidity, etc, sometimes even age of resin (they definitely have a shelf life).  That might be up to 48 hrs or even longer, but in general when done right polyester resins should be able to be popped out of their molds in 4- 24 hrs though probably still not thoroughly cured yet.

Keep in mind that coasters can be hard to do with resin because of the facts that hot and or wet liquids may be sitting on them for long periods of time, so that alone can cause problems if there's direct contact.

P.S.  Here's just one video showing how to use polyester resin in a mold with embedments... it's using the Tap Plastics brand of polyester resin:
http://www.youtube.com/watch?v=Y0Wp9CmSKFY
There are many more videos at YouTube showing the use of clear "resins" that can be helpful too, but be aware that sometimes the makers will say they're using epoxy resin when they're using polyester resin (or vice versa) or not realize that Easy Cast is an epoxy resin but different than the other epoxy resins, or something similar.  There will also be a load of videos at YouTube where clear polyester resin is used between layers of fiberglass cloth and that's not what you want to do (and often won't be using an art/craft quality polyester resin).

And here are a bunch of lessons on making coasters with "resin" (both kinds, several ways) though I haven't checked them all out:
http://www.google.com/search?q=how+to+make+coasters+with+resin+mold
http://www.google.com/search?q=how+to+make+coasters+with+resin

.

 
« Last Edit: December 25, 2010 10:42:55 AM by Diane B. » THIS ROCKS   Logged

POLYMER CLAY "ENCYCLOPEDIA" 
http://glassattic.com/polymer/contents.htm
few of my photos
http://s96.photobucket.com/albums/l163/DianeBB
(had to move them from YahooPhotos, so many now without captions)
amaliadc
« Reply #1635 on: December 25, 2010 04:12:17 PM »

Thanks for the info!

Sounds like either I switch to epoxy or abandon the project, given my current environment. I'll try one more time when I get the new mold and let it cure longer, otherwise I guess I don't have the knack for resin Wink

I am considering just using mod podge to apply the photos to these coasters....does anyone know if that's possible, given it has a round insert (I assume on the back too)?

http://www.elegantquilling.com/product/EQ20042/Hexagon-Coaster.html
THIS ROCKS   Logged
Diane B.
Offline Offline

Posts: 5062
Joined: 01-May-2004

GlassAttic --polymer clay "encyclopedia"


View Profile WWW
« Reply #1636 on: December 25, 2010 05:29:51 PM »

ModPodge (or thinned down permanent white glue) is the usual thing used to seal porous materials before putting in resin and also the adhesive often used to "glue down" a photo or other paper image to the back of a "cell" when doing that, and it's perfectly fine to use it just to glue down a photo/etc to a permanent back.  You can then also use something like epoxy resin or gloss polyurethane/Varathane/etc or vinyl floor polish** or other things as a thick coating on top, particularly if you leave the whole thing inside a cell (frame, etc) so it will be protected to some degree. 

Quote
I'll try one more time when I get the new mold and let it cure longer, otherwise I guess I don't have the knack for resin

Actually, most resins do have a learning curve for everyone, though there are some (which often have disadvantages for some situations) that work pretty well from the beginning or the maker just gets lucky.  Grin
There are people (and posts) here that have liked other kinds of resin too, so maybe they'll chime in as well.

** see the category on the page I linked to before called "Simulations of Resin"...and also see this page for more details on some of those other clear finishes like Varathane and Future, etc:
http://glassattic.com/polymer/finishes.htm
THIS ROCKS   Logged

POLYMER CLAY "ENCYCLOPEDIA" 
http://glassattic.com/polymer/contents.htm
few of my photos
http://s96.photobucket.com/albums/l163/DianeBB
(had to move them from YahooPhotos, so many now without captions)
motoredxheart
« Reply #1637 on: January 07, 2011 10:43:53 PM »

I tried searching so I'm sorry if this has already been answered...

I made some pendants with resin and when I stuck a small polymer clay charm in the charm sank straight to the bottom.
Is there a way to make sure it doesn't sink? I don't want it to go all the way down, I would like it to go right in the middle of the pendant.

Thanks!
THIS ROCKS   Logged
Diane B.
Offline Offline

Posts: 5062
Joined: 01-May-2004

GlassAttic --polymer clay "encyclopedia"


View Profile WWW
« Reply #1638 on: January 08, 2011 09:14:45 AM »

The general way to add inclusions you want to stay where you put them (and not all over like glitter, etc) is to pour in a layer of resin then wait awhile for it to gel up.  Then put the item on that layer and pour more resin around it to fill up the mold. 
It's sometimes good to pre-dip the item into resin to be sure you won't trap air bubbles around the item while pouring the second layer too.

Sometimes lightweight things will rise too so may have to keep pushing them down for awhile (or if on the bottom, glue them down).
« Last Edit: January 08, 2011 09:17:07 AM by Diane B. » THIS ROCKS   Logged

POLYMER CLAY "ENCYCLOPEDIA" 
http://glassattic.com/polymer/contents.htm
few of my photos
http://s96.photobucket.com/albums/l163/DianeBB
(had to move them from YahooPhotos, so many now without captions)
hello color!
« Reply #1639 on: January 10, 2011 09:24:29 AM »

Robin,

30-50 casts is about normal for most molds. (Obviously, molds with more detail and texture will not last as long.) Does that book talk about jewelry scale stuff at all? IMO it's so different from casting larger objects and I could use some tips, like things to use as tiny mold straps, etc...

ChantaL,

I don't think you can get a mirror finish on resin by buffing. Your best bet is either keeping the interface that resin forms with air when it's still liquid or using a very smooth mold. People have gotten good results by using plastic packaging, but the down side is that it can only be used once and most of it is too big for jewelry. I can't speak to it myself, though, since I'm quite a fan of the matte finish.

Amalia,

You can get hexagonal coaster molds that are made especially for resin here. I don't remember if they're polyethylene or polypropylene, but they'll definitely release. You should still use mold release with them, though, since all molds stick to some degree.
THIS ROCKS   Logged
Threads you might like:
Pages: 1 ... 162 163 [164] 165 166 ... 172 Jump to page:
  Send this topic  |  Print  |  Bookmark  
 
Jump to:  



FacebookTwitterPinterest
only results with images
include swap threads
advanced search



your ad could be here!

How-To Videos
Philippa Gregory Reads from Her Book the Red Queen
Author Regan Hofmann on Her Greatest Achievement
Novelist Lynda La Plante Introduces the Red Dahlia
Archbishop Carl Bean Talks About His New Book: I Was Born This Way
Lori Armstrong Reveals a Bit About Her Novel No Mercy
Latest Blog Articles
@Home This Weekend: Lamp Transformation
Book Review: Handmade for Baby
Tute Tuesday: Warm Those Piggies!

Comparison Shopping




Support Craftster
Become a
Friend of Craftster

Buy Craftster Swag
Buy Craft Supplies
Comparison Shopping

Craftster heartily thanks the following peeps...
Moderators

Follow Craftster...






Powered by MySQL Powered by PHP Powered by SMF 1.1.11 | SMF © 2006-2009, Simple Machines LLC
SimplePortal 2.3.5 © 2008-2012, SimplePortal
Valid XHTML 1.0! Valid CSS!

Copyright ©2003-2015, Craftster.org an Internet Brands company.