Replies

1. 
   Marcello | Jun 10, 2003 08:35pm | #1

   Adam,

   None, no problems.  The residue of the tape on the other side can be sanded off.  I do this very often.  I don't use duct tape though, I use a piece of wax paper attached to a caul and clamped to the piece in turn.  That way there is no sagging at the bottom once you start to pour the epoxy. 

   Marcello

2. 
   GaryRose | Jun 10, 2003 09:07pm | #2

   I have done exactly what you are considering.  You might need to back the gap with something stronger than just duct tape to prevent sag or breaking loose.  It may be overkill, but I first back the gap with wax paper, then smooth masonite and then tape this over the gap.  Be sure to use adequate tape beyond the gap and support the piece on a bench.  Also, tap the container of mixed epoxy on the workbench to help evacuate small bubbles.  Clear epoxy appears to take on the color of the surrounding wood and is not obvious.  I then sand it, which creates a worrysome matte finish, but when you put on your clear finish, it disappears.  This is just my own approach to this.  Hope it helps.

   Gary Rose

3. 
   AlanTurner | Jun 10, 2003 09:48pm | #3

   I would wonder whether there might be some further movement of the wood, with the result that the epoxy would loosen over time, with the change in seasons.  A butterfly, or dutchman, either allthe way through, or just up 1/2 way from the bottom, would cure this, I would think.  Maybe 2, one towards each end of the split, so it doesn't run any further.  Just a thought.

4. 
   Elcoholic | Jun 10, 2003 10:20pm | #4

   I've done this several times with Walnut and Koa bark inclusions and checks.  I use tape to dam-up the back side.  Bubbles are always a problem but lightly playing a propane torch across the surface pops them.  I hardly get large fills in one pass as the epoxy still flows injto the nooks and crannie well past the point where it's still pourable.  I use West Systems.  I disagree with using clear though, to me it looks like a big hunk of plastic.  Instead I use polyester colorant.  I'll mix in black thoroughly and then just swirl in some brown and pour it or vica versa.  You can also use sawdust.  Just remember to mix the catalyst and resin before you add the color or sawdust.  I'll shoot a picture or two tonight and post them tomorrow.

   John O'Connell - JKO Handcrafted Woodworking

   Life is tough.  It's tougher if you're stupid - John Wayne

1. 
   adamws | Jun 11, 2003 05:28pm | #5

   What's the best way to get ahold of the West System Epoxy?  Also is there a particular product or epoxy in this brand name that I'm looking for?  And, about how much time will I have to work with it before it hardens?

   Thanks for the help,

   Adam

1. 
   Quickstep | Jun 11, 2003 06:02pm | #6

   Many boat supply places carry West. One downside is that you have to buy their pumps to get the right proportions and this can add up as the epoxy is also fairly expensive. That said, I think it's worth the investment; I use it for all sorts of stuff, everything from glue to filler. PS, I've used it to fill knots as you've described. I use electrical tape to build the dam. I put the tape on (multiple peices if necessary), then remove it and do it again. The first time removes dust that may impede adhesion that could cause leaks. After I fill the crack, I mix up another small batch and keep topping it off as the epoxy settles into the crack. As it begins to thicken from hardening I let it "overfill" a bit and then sand it level later.

1. 
   Jamie_Buxton | Jun 11, 2003 06:09pm | #8

   While it is true that epoxy is expensive, you don't have to buy West's pumps that automatically pump the resin and catalyst in a 4:1 ratio.   Instead, use any other measuring device  -- a teaspoon, a measuring cup, whatever. 

2. 
   erich | Jun 11, 2003 06:04pm | #7

   Adam,

        I've been watching this post closely as I am interested in filling some significantly smaller gaps, almost really big pores with epoxy before finishing, (Bigger than you could fill with pore-filler).  Actually, I've already done it and it looks okay, but the brand of epoxy I used, something from H.D. (I know, I know...), isn't as clear as I would have liked.  So I'm seconding your request for some brand names or specific items from West Systems.  Good luck!

                                             Erich

3. 
   Elcoholic | Jun 11, 2003 11:00pm | #11

   As others have said boat supply houses are a ready source.  West Systems is so common in woodworking that I can get it from my local hardwood supplier.  The mini-pumps are well worth the $10-15 bucks.  I use #105 Resin and #206 (slow) hardener.  Pot life is about 10-15 minutes in small batches (1 squirt of each).  The bigger the batch the more heat is generated so the shorter the pot life.  Once you spread it into a thin film the cure rate really slows down.  I have had no problems routing, drilling, sanding, planing or scraping this stuff.  Although I haven't used it in blonde woods.  Cleans up well when wet with acetone.  From the West Systems Site:

   206 Slow Hardener

   206 Slow Hardener is a low-viscosity epoxy curing agent for use when extended working and cure time is needed or to provide adequate working time at higher temperatures. When combined with 105 Resin in a five-part resin to one-part hardener ratio, the cured resin/hardener mixture yields a rigid, high-strength, moisture-resistant solid with excellent bonding and coating properties. Not intended for clear coating.

   Mix Ratio, Resin:HardenerPot life at 72°F (22°C)Cure to a solid stateCure to maximum strengthMinimum recommended temperaturePumps required

   5:1*20 to 25 minutes9 to 12 hours1 to 4 days60°F (16°C)300, 306 or 309http://www.westsystem.com/John O'Connell - JKO Handcrafted Woodworking

   Life is tough.  It's tougher if you're stupid - John Wayne

1. 
   AlanTurner | Jun 12, 2003 12:00am | #12

   I secnd the vote of John O'C.  Get the pumps.  Once the cans are open with the pumps inserted, it lasts for several years in the can, without taking the pumps out.  They just sit there, ready to go.  In terms of pot life, if after mixing you will put it into a flat container, such as an alum.  pie plate, you will find the pot life extended.  This is a handy shop product; it will not go to waste.  I too use the slower setting one.

5. 
   parrothead | Jun 11, 2003 06:46pm | #9

   Adamws, not sure if you would be interested in this but and alternative to the epoxy would be "inlace". It is and epoxy based liquid that hardends and gives the apperance of stone. I my self have not used it yet, but I have some pieces of burl that I want to use for some jewerly box lids. Burl is notorious for void and I think I will try the inlace. With the size that you are filling you might want to fill 3/4 of the way with any epoxy and then top it off with the inlace, it is a little expense.

   Here are some links on the product:

   http://www.pennstateind.com/LACE.html

   http://www.choicewoods.com/inlace.htm

   Good luck

   Mike

   We are the people our parents warned us about. J. Buffett
6. 
   Andrew | Jun 11, 2003 07:02pm | #10

   One thing I would recommend is using a scraper instead of sanding to get the expoxy flush with the surface. With sanding, the epoxy dust is worked into the surrounding wood and leaves a mess (especially in lighter woods).

7. 
   jvs | Jun 12, 2003 02:56am | #13

   I have used West System epoxies (with both hardneners), and they do work great for this application and as high-strength, gap filling adhesive.  For medium to dark woods (cherry, mahogany, and darker) I usually do knots in black for contrast.  Powdered dyes work great for this, and I once used finely ground charcoal (30 seconds in a mortar and pestle), which worked fine, too.

   I ran out of resin once, and could only find System 3 locally.  Because of the 2:1 ration for the standard product, it is a little easier to work with in small batches.  With the adjustable cure times (mixing hardeners) and adjstable viscosity (letting a batch with a sub-critical hardener mix run to a complete cure and adding the final hardener from there), it has replaced West for me.  The cast of the cured epoxy is slightly more amber than West, which cures almost like glass; if you are using it straight, this might make it a better match for lighter woods (which will darken to a shade of amber with any oil- or solvent-based finish), but it is not enough to make any difference if you are coloring or tinting the product.  You can get fine-tuned cure times out of West, too, but it is almost impossible to measure West's hardeners accurately in batches of a few ounces or less.  S3's ratio works great in dixie cups.

   System 3 also makes T-88, which formulates thicker than either normal S3 or West and mixes 1:1, but this won't make much difference if you are filling either with wood flour or silica for anti-sag. 

   System 3 and West are kind of the Coke vs. Pepsi of the epoxy world--I guess I've switched to Coke.  There are many vendors for these--among others, Lee Valley carries West, and Woodcraft carries System 3 (they may have a local store for you, too).  

   /jvs

8. 
   sailalex | Jun 12, 2003 02:25pm | #14

   My only additional comment is that the epoxy is a lot harder than the surrounding wood and when you sand it, it is very difficult ( if not imposiible) to get a totally flush surface; the wood always sands quicker, and lower, than the epoxy.

1. 
   adamws | Jun 12, 2003 05:42pm | #15

   Well, $50 later and the West Systems Epoxy is on its way.  Thanks to all for the valuable comments.  I'll let you all know how it turns out, unless ofcourse I completely screw up and am to embarresed to show my face again...

   Thanks,

   Adam

1. 
   Elcoholic | Jun 13, 2003 01:30am | #16

   Here's the pix I promised.  As Sailalexsaid leveling can be tough since epoxy is harder than wood.  My first chice for leveling is my Bosch 4 x 24 beltsander with the sanding frame.  Otherwise I'll get it flush with a bastard file before I use the RO.John O'Connell - JKO Handcrafted Woodworking

   Life is tough.  It's tougher if you're stupid - John Wayne

   
1. 
   Robbie | Jun 13, 2003 01:56am | #17

   Make certain that you either scrub with soap and water or alternatively sand the cured epoxy surface.  West Epoxy leaves an anine blush on the surface upon curing.  You may not see it, but it is there. 

   If not removed prior to finishing, it can cause bad finish adherance to the specific spot. 

   BW

1. 
   Jamie_Buxton | Jun 13, 2003 02:37am | #18

   The West epoxies are designed to really penetrate, to completely wet the fiberglass, so they do have a tendency to get out on what will be a finished surface and sink in.  I think that sinking in is what causes that stain.  I've had success putting a first coat of finish on the surface before I put the epoxy on.  I'm generally using wipe-on varnish, so a quick swipe is all that is necessary.   The one coat of finish reduces the epoxy penetration.  Of course, most of that first coat of finish gets sanded away when you're grinding the epoxy flat, but that's okay.

2. 
   Robbie | Jun 13, 2003 05:02pm | #19

   Jamie:

   Wasn't sure if you were responding to my post.  If so, here goes:

   Anine blush is actually a chemical reaction that forced a very slight film to form on the exposed surface of the epoxy.  It really doesn't have any color, it is just a very slight surface film that you can't see, but you know is there.  It must be removed prior to finishing. 

   While most of us would sand flush before finishing anyway, that is not "always: the case.  However, it should be.  Note, sanding the blushed epoxy will quickly "pill" or gum up your sandpaper.  No way around it.  Even with Fre-cut.

   Bob