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Christos
14th May 2010, 09:09 PM
I have never used epoxy to fill holes in wood. I have a few holes that are from 1 to 8 millimeter wide. Some going all the way through the wood.

So this could be a good time to try out something new.

I have read on this forum about what people use and have some idea of what I will get. That being said and with me not actually sure on a few things some questions come to mind.

I want to know what people think of the brands they have used? How well it took colour? If the colour faded over time? From where to purchase the colour (liquid or powder)? What the viscosity is? Depending on brand will it fill holes in one application or several application? How long is the shelf life?

Please feel free to add anything that I might have missed.

P.S. Should also add how well does is sand or plane?

joe greiner
15th May 2010, 09:31 PM
Regarding shelf life, I've had good and bad luck. Manufacturers are at the mercy of vendors to rotate stock, and the date codes are not always accessible before purchase, regardless of vendors' diligence. JB Weld is reputed to have unlimited shelf life; Loctite (Henkel) is one year; Permatex two years. The Permatex date code is printed on a flange which protrudes from the back of the blister pack. The Loctite (last I checked) is printed on the back of the label, inside the package. The packages may have a toll-free telephone number for assistance in deciphering the codes, which are similar but not identical.

JB Weld is opaque, grey when mixed and hardened. The "clear" epoxies generally fade to amber over time.

I use 30- or 60-minute formulations for working time. The 5-minute doesn't allow much working time, and takes a day or two to achieve rigidity.

3M has a variety of very low viscosity epoxies, but I don't think they're available at retail, or in small quantities. Bright orange at that. Mostly used in the construction and manufacturing trades.

Sources: For Loctite, Home Depot and Lowes up here; probably Bunnings for you. Permatex at auto parts stores. JB Weld almost everywhere.

For best adhesion, I rout the holes with a dental burr, or a small router bit, in a Dremel to remove punky wood. Undercutting can enhance purchase.

I don't add colour per se. I usually mix coffee grounds (fresh or spent), metal powder, or key-cutting shavings (usually brass and/or aluminium) into a mortar for filling. Some folks like to use crushed stone, turquoise in particular. Soft additives work best for finishing; harder minerals may be difficult to cut and sand. I like to fill the gaps proud of the final surface, then make the last cuts and sand flush. I don't think it matters whether the holes are filled in stages or all at once, although large holes might benefit from staged filling to reduce thermal shock.

Some stunning effects might be had with combinations of the additives, but I haven't gotten a round tuit yet.

Cheers,
Joe

cultana
17th May 2010, 03:10 PM
The last time I had holes to fill similar to your hole range I just used Araldite. It was/is the only epoxy available for me anyway. Any other varieties cost too much to get shipped in.

Since I was patching timber I got hold of a scrap of the same timber and weather age and used a harsh #40 paper to get some fine sandings. Mixed that with the epoxy and used that in the holes. With big holes widen it out as Joe mentioned. I also tape over the bottom so it does not run through. Again it pays to leave some glue proud, both sides where possible, of the filling and sand it back.

So far I have the only colouring I use is fine sandings. If I need a variation I mix up different sandings to get the necessary match. This means I have a whole bunch of little tins of different wood sanding colours.

Christos
18th May 2010, 10:47 PM
Come on people must be more then just two who use epoxy to fill gaps.

m2c1Iw
18th May 2010, 11:43 PM
What sort of wood, what type of look are you trying to achieve.

There are many types of epoxy 1:1, 2:1, 5:1 along with hardeners, have a read of the Bote cote site Welcome to BoatCraft Pacific (http://www.boatcraft.com.au)
this will give you some hints. I've not tried it but the Poor on Gloss might be good in this application.

For filling holes and voids I believe casting resin maybe a better choice as it stays clear, Bunnings have it but I've never used it.

My results with epoxy for filling surface defects has not been good as it is an adhesive first and foremost. It will go opaque and it's difficult to get a bubble free fill (a hot mix helps better viscocity).

It's better if it is coloured and there are many options from ochre, paint tints, wood flour, Feast Watsons Prooftint plus the tints available from the epoxy suppliers although the colours are a little limited.

Hope this helps a bit, experimentation on some test pieces is the key.

Cheers
Mike

cultana
19th May 2010, 02:35 AM
pour on Gloss and such similar epoxy products are very liquid and are designed in general to provide a horizontal surface. Not a good filling product for your use.

But you did not mention what you are filling besides wood, ie what is the end item?

Here:
http://www.woodworkforums.com/f187/my-second-piece-slow-progress-104663/index2.html#post1045540
The top has epoxy, Araldite, fills in the timber. They are sort of obvious as they are a pale gray colour from being sanded. Once pained with either an epoxy or poly the correct tone of the patch will come through. These are made using the 5 min Araldite mixed with fine sanding dust. They will not yellow as the main colour is natural timber so it also blends with the main timber better than using some other colouring process.

Also in this picture:
http://www.woodworkforums.com/members/53535-cultana/albums/chair/2952-back-rest.jpg
The top piece , left top corner has been patched using standard Araldite and sanding dust from a piece of the red timber top cap. It is not noticeable.


I have a few other pieces completed that I have done in a similar way, I could post a pic or two if you need a closer look see.

Mr Brush
19th May 2010, 06:08 AM
I use Techniglue (fairly thick 2:1 mix epoxy, easy to keep bubble-free), and keep a few assorted small bottles of FW Prooftint for colouring where required. Works a treat, and the colour seems to last.

I used to stuff around making fine sawdust from the same timber I was filling and mixing it into the epoxy, thinking it would be the best colour match. Doesn't really work IMHO - the mix comes out a much darker colour due to the epoxy anyway, and you can get as good or better colour match using Prooftint.

The small bottles of Prooftint are perfect for this, and are so cheap that you can keep a few different light/dark tints handy.

Christos
19th May 2010, 08:23 PM
Thanks for the replies fellow wood workers.

I have been doing a bit of research on some epoxy products, mainly by the web sites of the products. What I am not able to locate easily is how long a shelf life a particular product has after it is opened.

Lets say that I go and buy brand x use about 10 percent of the product and then put this on the shelf. I may need to add colour(tint) and leave that on the shelf. What are peoples experience with the brands that they used and how long did they leave these on the shelf before using them again? Were they usable after the period of leaving them on the shelf?

Christos
19th May 2010, 08:48 PM
But you did not mention what you are filling besides wood, ie what is the end item?

Here:
http://www.woodworkforums.com/f187/my-second-piece-slow-progress-104663/index2.html#post1045540
.

I am building a fish tank stand. http://www.woodworkforums.com/f11/fish-tank-stand-wip-slow-progress-116728/

And just like you on your above thread slow progress. :U

Ozartisan
19th May 2010, 08:58 PM
Christos
I have had excellent results using West System epoxy. (No5)
Have stored & used it successfully after 12 months.
Once cured properly (at least 24 hours - 48 if you can) I found I could plane, sand, polish quite well.

m2c1Iw
19th May 2010, 08:58 PM
Thanks for the replies fellow wood workers.

I have been doing a bit of research on some epoxy products, mainly by the web sites of the products. What I am not able to locate easily is how long a shelf life a particular product has after it is opened.

Lets say that I go and buy brand x use about 10 percent of the product and then put this on the shelf. I may need to add colour(tint) and leave that on the shelf. What are peoples experience with the brands that they used and how long did they leave these on the shelf before using them again? Were they usable after the period of leaving them on the shelf?

From my reading most of the epoxy adhesives have a long shelf life. Having said that I have seen manufacturers quote as low as one year and up to several as in five plus.
The experience from hobbyists/boatbuilders that use the products infrequently is the shelf life is long up to ten years.
Georgeon Bros/ West System say five years and that the resin will thicken and the hardener will darken in colour but the adhesive qualities will be unchanged.
Most professionals probably do not have quantities for long periods or if they do they would dispose of anyway so any risk to quality and durability is removed.

If tinting add only to the quantity of resin intended then add hardener after mixing if this procedure is followed a tinted batch of resin should last indefinitely.

I use both paste/Techniglue and liquid/Botecote and have product sitting on the shelf for over 3 years and would not hesitate to use it.

Cheers
Mike

Frank&Earnest
19th May 2010, 11:53 PM
Since reading Joe's advice about 2 years ago, I am doing what he said above. I bought two tubs of 1+1 epoxy, 1/2 kg each and used about 10% of it so far. For our purposes, my guess is that it will last 10 years as Mike says. As colour goes, I go for coffee as it looks as a sap streak or knot. I only match the color for hairline cracks and for that I go for CA and same wood sawdust.

REBZZ
20th May 2010, 11:59 AM
Most Epoxy will last indefinetly provided the lids are kept airtight. In saying this there are a small amount that will have a short shelf life, a good test would be to mix some up and if it cures it will be fine. Manufactures must put a shelf life on products to retain some quality control. I have and use epoxys at home that are 10 years past there date and still retain their adhesion qualities. If you need any advice in Adelaide contact Resimax and they will help you out.

old pete
20th May 2010, 12:44 PM
Hi Christos,

Best to use one of the marine epoxies available from ships chandlers. I use British Paints brand 'Epiglue' for all my gluing and filling.

I never try to simulate the color of the piece being repaired Just doesn't work unless you want to follow up with a one or two hair brush and paint on the grain to match the local grain. Use a color that gives a contrast that makes a statement.On Blackwood for example i'd use a deep green that looks terrific.

For color I use dry paint colors form the local art supplier and I add plenty to the mixed epoxy so the color is dense and perhaps more importantly it makes it much easier to sand the job after it has cured. It's pretty difficult to sand off straight epoxy filler from soft timber such as Huon Pine without sanding to much off the surrounding area due to the differential density involved. The sanding dust is pretty obnoxious so use appropriate PPE mask.

Another technique is to use clear casting resin available from scientific suppliers or fibre glass shops and within this to embed colored stones and other artifacts of your choice. I never do this because i suspect our dinner guests would find the table more interesting to look at and talk about than looking at and listening to me:~. This method can look anywhere between fantastic and just plain kitch. The secret is to not overdo things. I haven't tried to color this material so can't comment on that. Others may know about this..


Good Luck

Old Pete

Christos
21st May 2010, 02:48 AM
Thanks for the post fellow wood workers. :U You have given me some more things to think about.

Christos
31st May 2010, 10:41 AM
Just a quick update on this. I ended up purchasing the West System epoxy system from Carbatec. The 1liter / 200 mills pack and managed to pick up the mini pumps from another location, just to make it a little easier to measure out.

We used this on Sunday to epoxy a small wedge to a bit of wood and used the filler with the rest of the epoxy and just poured it into any gaps. The friend really liked using the stuff.

Sebastiaan56
31st May 2010, 04:58 PM
Im surprised I didnt see this thread earlier Christos. I use what you have chosen. It works well for me. Just be aware of the health risks associated with exposure over time. I recommend you read Kim's experience over at the ANZLF, see here Australian/New Zealand Luthiers Forum :: View topic - Warning! Epoxy Grain Fillers, be very, very careful (http://www.anzlf.com/viewtopic.php?t=1056)

Christos
31st May 2010, 07:59 PM
Interesting read. As with everything I try to be cautious.

Harry72
31st May 2010, 10:40 PM
I've used it a bit, its better than casting resin for filling in hardwood. Its sets hard quickly(24hrs in normal weather)and works much nicer too starting with handtools :) things like drips can be cut off with a old chisel while the resin is still in gel stage(couple hrs), once its set a hand plane or like I do a flat spokeshave for the roughing down then a card scraper for the best finishing tool for flat work. Then hit it with a random orbit sander to the grit needed for the finish type being used.
In 50ml I tint with a drop or two of Ubeauts dyes, particularly the cedar for darkwoods comes out a dark smokey green black.

Any leftovers I pour into some pvc pipe with one end taped up... gunna try them on the lathe one day :D

derekcohen
31st May 2010, 11:20 PM
It depends on what you want to do.

As a glue, one that will provide the highest strength, be totally water proof and have a touch of flex, the use two-part West Systems. I used this for many, many years repairing surfboards and windsurfers. It is fantastic quality. Excellent shelf life. The only negative is that proportions are important when mixing. The pumps make this a no-brainer.

Another advantage of epoxy as a glue is that it is gap-filling. If it is too runny, add micro-balloons to thicken it up. Or talc (powder).

You can colour epoxy. For tints, if you are looking for a close match, get some of the cement tints from Bunnings. I just keep a bottle each of black, brown and tan, and then mix as I need. Generally black is a good choice for most occasions. A little tint goes a long way.

For small jobs of filling holes, especially where you just want it done fast and the "fix" is not structural, the any of the 5-minute epoxies will do fine. I use these frequently.

Note that all the cheaper epoxies are not UV resistant and will become yellow over time. West Systems does offer a UV-resistance epoxy, if you want one that remains clear.

Polyester resin, as opposed to epoxy, is quick setting and cheap. It has a greenish tinge, sets harder and is more brittle. Not water proof. The only advantage is that it is easy to use as the two-part mix is not critical. Probably a better choice than expensive West Systems if used as a filler of holes and tinted black since it sets fast and is so cheap.

Regards from Perth

Derek

wheelinround
3rd June 2010, 03:16 PM
Here is a sample of epoxy used in woodwork ( I just got permission to post these photo's)

Aris has used Clear, Opaque and coloured the clear is where the multi-colour strips are. The strips are actually ribbon cable used in electrical/computers components. This along with his other work in use of epoxy was demonstrated at an OTGA Ornamental Turners meeting 2 weeks ago.

Aris is an artist, carver & turner and his work is amazing.

The epoxy and resins used are not those bought from Caba or Bunnies.

Christos
3rd June 2010, 08:57 PM
That is some excellent work.

Christos
7th June 2010, 08:53 PM
This is just an update on what I have been doing. I purchased the West System epoxy and alone with that I also purchased some Feast Watson Prooftint black. I had a few holes to fill. :U

138702

This is part of a fish tank build, that is with out a doubt very slow progress.

wheelinround
7th June 2010, 08:58 PM
:o a few holes, maybe you should have used a scraper to save on some hard rubbing back, a good sharp chisel will work just don't take make any more holes.:;

Christos did you get the slow hardener or fast??

You can use Laser printer thermal inks for colouring black also.

Christos
9th June 2010, 08:39 AM
I ended up getting both the fast and slow. My thoughts were that I just might use this during summer as well as winter. :U.

Started to clean up the epoxy firstly with a chisel and then with sand paper of the little bits left. Slowly slowly getting there.