'Z' Poxy

[Graham Long]

Hi,
I just used 'Z' poxy for the first time in an attempt to fill grain, it ended up a discolouring the wood with a reddish colour.
Is this normal? or do I have a crook batch.
I've sanded most of it off, but there is still (of course) some caught in the grain.

Is there any other clear product that's suitable for grain filling
Cheers
Graham

[kiwigeo]

What wood are you grain filling?

Some pics would be handy.

Cheers Martin

[J.F. Custom]

Hi Graham.

No it isn't normal, though I have not used Zpoxy.

I have used West System Epoxy, but either way, they should be clear or very near to it. Epoxy can get a very pale yellow tinge to it, and can also yellow over time and exposure to UV, but red straight up? No. I have seen very old epoxy go an amber colour.

Unless you have an unusual bad batch or it is very old, it sounds most likely as though you have a contaminant in there, or that it is bleeding colour from some timber you have used - as Martin is suggesting by asking what timber you are using.

What colour was it when first mixed in the jar? If either component was coloured, or when mixed it showed red tinting, it should not have been used. If it was clear in the jar, than it is leaching from the timber itself.

Sanding back to bare wood will help, but as you suggest, you won't be able to remove that which is in the pores.

Good luck.

Jeremy.

[Bob Connor]

Z-poxy has an amber cast to it so it will darken woods a little.

I actually like what it does to most timbers.

Regards

[kiwigeo]

Hi,
I just used 'Z' poxy for the first time in an attempt to fill grain, it ended up a discolouring the wood with a reddish colour.
Is this normal? or do I have a crook batch.

I know it may sound like a stupid question but it has to be asked. You're not slapping Zpoxy onto a spruce top are you?

[Graham Long]

The guitar is Tiger Myrtle back and sides (not that that needed filling) Qld Maple neck and sitka Spruce sound board.
The 'Z' poxy actually has a pinky colour to it after mixing. I've attached a couple of photos, doesn't really show it very well as most of it has been sanded off, but you can still see the dark colour caught in the maple grain on the neck.

[Allen]

Depends on the wood on whether it will give a colour cast to it. I use WEST systems and on some woods it seems to give a redder cast to them. Qld. Maple and NGR are notable ones in that they do become far redder. But it is a colour shift that I like. The Qld. Maple tends to look much more mahogany like with the epoxy pore fill. And NGR really comes alive after an application.

You just posted while I was writing this up. With Tiger Myrtle the colours get much more vibrant but I wouldn't say it turns red. More like you just wet the surface with water.

WEST systems is virtually water clear when new. As the hardener gets a bit older and their is air left in the container it can get a bit of an amber cast to it, but it doesn't seem to ever affect it's curing properties. Nor do I notice any more dramatic colour shift.

[Craig]

The 'Z' poxy actually has a pinky colour to it after mixing.

That doesn't sound right . The resin part of the mix is clear in colour and the hardener a golden amber. There's no hint of a pink or red in the mix.

What are you mixing it on ? and what utensil are you mixing it with ? There's a chance of some colour leaching from whatever your mixing it on or with .

Be very careful when using Z-poxy or any similar type epoxy fillers. Some folk become sensitized to it with disastrous results.

Another problem is Epoxy 'Blush' , which can rise to the surface (through your finish ) at a later date. This destroys your finish totally , so BEWARE . Google Epoxy blush

[mhammond]

The last package of Zpoxy I purchased had a reddish cast to it. It looked good on rosewood and mahogany. On maple I can imagine it was not so pleasing. This was the first time it came with the red color. The other (several) times I purchased it, it was a golden amber.
I dunno what to tell you....
Mikey

[Dennis Leahy]

Is anyone selling this soybean-based epoxy in Oz or NZ yet?

EcoPoxy : http://www.ecopoxysystems.com/index.html

Almost no smell at all. If it is as safe as they say, Kim could use it instead of Vegemite on sandwiches.

I had kinda-sorta reviewed it before (the regular, amber-ish colored stuff), and it looked very promising (except on 'white' wood that you want to keep 'white.')

Well, they have a clear one now too. I have some samples, and indeed, it is clear.

I suppose this is worthless info if you can't get it locally, as it would probably be too expensive to ship.

Dennis

[Dominic]

This appears like a great alternative to normal epoxy Dennis. You have used it before, how does it go under finish? And what type of finish do you use. Any issues?
They are making an off-shore racing boat with it so it must be pretty strong. Have glues as well.

I might write and ask if there is an Aussie distributor and/or see if I can order some and check out shipping. If it is non-toxic it might be OK. I keep wanting to use epoxy more often for more things but hate its toxicity. Perhaps this is the answer.
Thanks for posting.
Dom

[Graham Long]

The hardener is red! (Duh)
Am I using the right product?

[kiwigeo]

It says "finishing resin" on the packet and that's the correct Zpoxy product.

I'll check out the hardener in my workshop and report back re colour of same.

[kiwigeo]

A pic of the Z poxy in my workshop. Note that my bottles have been sitting on the shelf for 2 years and would be out of date. That said the hardener hasnt really changed colour since the bottle was fresh.

[Dominic]

Hey guys, I've noticed that the hardener gets darker with age. I just got some fresh stuff and compared to what I had left it was much lighter but still the warm amber colour. The red hardener could be from sitting on the shop shelf for ages before you got it. But I am sure a nice fresh batch should be light amber coloured.

I'd get some fresh stuff from a place that has turnover.
And if the red stuff sets OK keep it for rosewood.
Cheers
Dom

[Graham Long]

The Z poxy I bought came from a model shop in Brisbane, I've had it for about two months.
Can anyone tell me of a supplier that may have a better turn over.
Cheers
Graham

[J.F. Custom]

Wow.

Seems I was mistaken as to what to expect from Zpoxy.

As I mentioned, I had not used it - but assumed it to be similar to the West Systems. From those last images though, it definitely is not. West System can get a tint to it, darkens with age, but it is nothing like that. A little like a blonde shellac perhaps and as others have mentioned, that slight tint it can give to timber can look very appealing. I did not expect Zpoxy to have that much colour - looks more like an amber shellac. As others have mentioned though - horses for courses. You either like the end result or not but it should still perform it's function as a filler.

To clarify also my comment above "it should not have been used" was based on the assumption that if you want clear- and it wasn't clear in the jar, you won't get what you want. Not that it was not "usable" per se, but I would check the age and make sure it is still curing hard.

Jeremy.

[Graham Long]

Hi Jeremy,
Where do you get the Western Systems epoxy?
Graham

[greg]

A pic of the Z poxy in my workshop. Note that my bottles have been sitting on the shelf for 2 years and would be out of date. That said the hardener hasnt really changed colour since the bottle was fresh.

Hmmm... Last time I talked to my friend who is a major epoxy manufacturer, he said I could leave my epoxy on the shelf for 10+ years with no performance problems. I have various systems that are 5-7 years old that are perfectly fine for use.

The only things you have to do is keep them air tight, esp the hardener as it is hydroscopic in liquid form.

From memory the color change is due to air contact. I'll give him a call today since I have not seen him for a bit and get low down again.

As an aside, I have had him make me 'custom epoxy resins systems' in the past for various jobs (when I say custom, I mean tweaked recipes to affect color, open time and strength.) I'll chase up some info from a pore filling perspective.

[Dominic]

I get it from these guys http://www.amcsupplies.com.au/index.php ... =7_553_556
Also get casting resin and other goodies from them. Good fast online service.
Cheers
Dom

[Trevor Gore]

If you use the WEST stuff, be sure to use the 207 special coatings hardener (otherwise you might find it blooms, 2 years down the track).

[greg]

Just talked to my friend who makes and distributes epoxy resin. Good to be refreshed on these issues.

The amber color in hardeners is caused by 'impurities' in the product as a part of the manufacturing process. Over time the color can become more red, but it does not affect its strength properties. It does however affect the finished cured color. This is common among industrial resins.

Over the years with the West System product, depending on the hardener speed, I have never received an absolutely clear product. It has always had a colored tinge to it. Some of the resin systems I used I actually had my friend tint the hardener with ink to create a finish that hid the substrate. It meant I did not have to paint certain things. It is possible to get epoxy resin systems that are clear but there are compromises with the temperature needed to cure the product and the products viscosity. The off the shelf systems talked about in this thread are designed to cure in a window of temperature called 'room temperature', and within a certain humidity range. Because they are not made with Luthiers in mind but rather marine and other industrial fields, the coloration is not a component that manufactures address.

In talking with my friend, his perspective on pore filling wood is to lower the viscosity of the resin product so it can travel further into the grain, and to heat the substrate to expand the air in the substrate which both drives it out and sucks the resin back in when cooling. There are a couple of issues here for Luthiers that I see. In terms of thinning the resin, it is common to add a solvent but this can create a further set of issues with the cured resin product being porous and brittle and a wood substrate taking on the smell of the solvent used. There are however a range of 'reactive diluents' that can be added to products such as West, and along with playing with resin/hardener ratios, can lower viscosity for better pore filling results.

Applying heat would be is another kettle of fish. I have built and used a number of low temperature ovens over the years to cure epoxy resin built products, but 50deg for 24hrs or 60deg for 12hrs would not fly with your newly constructed spruce topped classical... me thinks. It is possible to develop a knack of using localized heat with a hair dryer/ paint gun set up while brushing resins on bodies but I am sure there would be a few cockups before you got the system down.

Interestingly, in talking with my friend he mentioned a visit to Fender where they were using an ester based product system called Duratech to do clear finishing. Many multiple layers sprayed, sanded and built up etc.

During our discussion, my friend asked why Luthiers are not using sanding sealers which are designed to stand the grain up and fill pores. Perhaps someone could shed some light on this. (By the way, I assume you guys are doing pore filling to stop pin holing when applying clear finishes... am I right?)

Anyways, I am keen to move project along and try some of these things out.

Thanks for the cool forum and great vibe here.

[Kim]

Sanding sealers bring long term adhesion problems and also cloud grain definition. They are unsuitable for use in instrument building simply because there is much point buying a nicely figured set of wood for top $ and then covering it over with opaque muck.

Cheers

Kim

[greg]

Sanding sealers bring long term adhesion problems

May I ask what type of problems occur? Is it adhesion issues with clear coat finishes?

[Kim]

Sanding sealers bring long term adhesion problems

May I ask what type of problems occur? Is it adhesion issues with clear coat finishes?

Yes of course. If the first product you lay down on the wood has questionable adhesion, then 'anything' you put on top it is going to be affected and come away.

Sanding sealers are nothing more than a 'finish' which has been compromised with added silica, (powdered glass) so it can body-up and fill grain and then sand off easily. The problem is that silica in itself has no ability to adhere to 'anything' So every gram of silica that is added to a base product is reducing that products ability to adhere.

Now if you are finishing a modern day project built with ply or a composite material like veneered MDF etc, both of which are quite stable during changes in relative humidity, then I guess (for some) such a reduction in a products ability to 'stick' could be an acceptable trade off to get the finish on, especially in a production environment. But when you have many bits of 'really' thin wood glued together over a framework of little sticks, then things are going to move lots and often as they expand and contract with changing 'days' within changing seasons.

Under those conditions you really don't want to trade off anything...this is not woodwork we are doing here, there are many more things to consider...tone and volume belong to thin and lite, structural integrity is in the design and one is the enemy of the other.....finding the balance is the key. The finish must not be allowed to interferer with that, but it 'must' adhere to that.

Cheers

Kim