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I wouldn't bank on that with all woods, all of the time!

Are you dry or wet sanding the WEST?

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Dry sanding Trevor, though it was so far only on my test panel. Worked great on EIR and Ziricote. I will get to sanding the 1st coat on a guitar tomorrow.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Thanks for the test and update Fred

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Thank You and Best To All

Thanks, Fred. Make sure you keep that dust under control!

One more tip: leave the WEST at least 24 hours before you hit it with nitro. Prior to that, the solvents in the nitro seems to soften the epoxy, which then gives some sink-back later. After 24 hours, the epoxy seems pretty impervious and you end up with a flatter finish. Not sure of the impact with other finishes.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

I think it must be the amber tone of the Z-poxy that creates the difference in the color after the next coat. I could even this out somewhat by careful application of Z-poxy in the bare wood area before the next coat was applied. I intentionally sanded through on 2 of my test panels and recoated. I could barely tell where the sand through happened after the 2nd coat cured, with Z-poxy it would be much lighter in that area. I found the same thing with the system 3 clear coat but did not like the variable cure times of that product in my somewhat cooler shop and the fact it needed an extra coat the get the fill I wanted.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

The easiest way is to mix with ratios other than 1:1 is to use graduated mixing cups and pumps and mix by volume.

For smaller amounts, I use these 1 oz. cups that are graduated in fractions of an ounce and in CC/ML.

http://www3.towerhobbies.com/cgi-bin/wt ... XK360&P=ML

For larger amounts I like to use 4-0z. specimen cups that are also graduated in fractions of an ounce and in CC/ML.

http://www.amazon.com/Specimen-Cups-Wit ... B0006GDBR2
http://www.amazon.com/ProAdvantage-Spec ... _sbs_hpc_7

For a 3:1 ratio, it's as easy as squirting in 30cc and 10cc, or 45cc and 15cc, etc. For a 2:1 ratio, 20cc and 10cc, etc.

If you use graduated cups, you don't need another tool such as a scale because you're already mixing them in a cup of some sort.

The nice thing about using graduated cups is that you can put both components in one cup instead of into two. You fill the cup with one component up to a certain line, then add the other component until it gets to another line. Then, mix. The problem with using two cups is that there will always be some leftover in one of the two cups, which means that your ratio is never 1:1. Instead it's 1:.98 or 1:.97, etc. Not to mention wasting a cup for every batch of epoxy mixed.

Yes, cups are a good option when using the pumps.

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jw ( o)===:::

On volume mix with West 105 and 207 it is a 3:1 ratio.

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jw ( o)===:::

I also use the graduated mixing cups for small amounts. It seems to work pretty good.

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Steve Smith
"Music is what feelings sound like"

I'm a newbie here and pretty much a lurker until I actually start on a guitar but I'll throw this in here.

I've used gallons of West System epoxy over the years for my furniture. I've used it for bent lamination, veneers, and even for joinery if it's a particularly complex glue up that requires a long open time. I also use it a LOT for filling voids, defects, etc. BIG voids. More like crevasses...

My comment is that it does not seem to be very fussy about exact mixing ratios. I use the pumps most of the time (IMHO not particularly accurate either) but as others said often that produces way more than one needs. If I need very small amounts I keep a couple eye dropper type nalgene bottles and count drops. I have also mixed with measuring spoons, graduated cups etc. I'm SURE that I've missed the 5:1 ratio the 206 hardener calls for by a fair amount many times and have never had a problem with curing. I like an amber tint in my finishes so I have not tried the 207 hardener and can't provide any info there.

As far as going off in the pot... 'Large' quantities, like say a 1/2 cup, mixed in a smallish pot will generate a lot of heat due to the chemical reaction. I've melted plastic yogurt tubs etc. being careless that way. Luthiers obviously don't need that kind of volumes, but in case you decide to build a boat , pot life can be extended considerably by spreading the mixed batch out in a larger container or tray so the heat can dissipate.

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May be so... may be not so...

http://www.solomonrossfurniture.com/

I have just completed my 1st fill with the West 105/207 and it went well. The cure time is longer than the Z-poxy but one coat per day works out real well as it is completely cured for sanding.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

I completed my 1st fill with the West 105/207 and am very happy with the results.



Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Great job Fred. That's exactly how it should look. No shiny wet spots, just even flatness.

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jw ( o)===:::

Thanks Joe, I always got the same results with Z-poxy but am seeing a little shrinkage in the pores on some guitars that were done 5 years ago, I am hoping the West will eliminate this. The product was a pleasure to work with other than the slower cure time.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Nice work, Fred.

Can I encourage you to post your process?

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Just wanted to say thanks for the tip of using a blow dryer with z-poxy. I just finished pore filling a Negra using a foam brush and a heat gun with zpoxy. First I squeegeed across the grain, then heat and foam brush. Te back went so well, I did the sides too. I have used zpoxy on about 4 guitars prior to this, and while I liked the result, I did a lot of sanding to get a level coat. Using the heat, I did one coat, waited a day, sanded with 400 grit, and cleaned with naphtha, and did another coat. I usually have to do a final coat thinned with 190 proof grain. It doesn't look like it this time. Thanks again!
Question: Anyone here ever put dewaxed shellac on top of zpoxy?
John

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John Nowicki

I spray 2 coats of shellac over the Z-poxy before lacquer all the time and am planning to do the same with the West epoxy.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

I go straight to nitro. Works fine.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Am I correct in understanding that the benefit of West over Z-poxy is that it's easier to blend sand-throughs (they become non-issues)? Are there further benefits? Does it make figure pop as effectively as Z-poxy?

I'm glad the hot air worked on the Z-poxy for you as it worked for me, John.

Here's an additional question about the West 105/207: As I am understanding it from this thread, the West 105/207 is relatively clear, at least until it gets ""old". So, aside from less issues with sanding through, it could also be good in a case where you don't want the hue that comes from Z-poxy? I'm thinking of cases where you might be starting with relatively dark wood and don't want the look to get any darker.

Thanks,
Pat

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There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.

Ditto

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I'm not a luthier.
I'm just a guy who builds guitars in his basement.
It's better than playing golf.

I have so far only done 2 guitars with West and they are just heading to the spray booth so I can't show results yet. I did 15 guitars with Z-poxy and liked what it did but I feel West does everything as well as Z-poxy. The only issue is the curing time is longer, I started waiting 24 hours before sanding to be sure it was cured. The only issue I had with Z-poxy is I always saw a bit of shrinkage into the pores after a couple years so am hoping West will be better.

As for blending sand through I had a couple spots and would be hard pressed to locate them after the fill is completed but this was Ziricote and I have not tried any other woods yet.

Fred

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Fred Tellier
http://www.fetellierguitars.com
Facebook page http://www.facebook.com/pages/FE-Tellier-Guitars/163451547003866

Correct. Fresh stuff is pretty well water clear.
How problematic sand-throughs are depends on the wood. Sometimes it's no problem, sometimes it is, even on the same species. I think it depends on how much "scrubbing" you do getting the stuff on and how much colour migrates into the epoxy. The sand-throughs you see are the ones where the colour has migrated from the wood (so the wood is lighter) then the coloured epoxy is sanded off, leaving a lighter patch beneath. One fix is to swab an off-cut with acetone to pick up the colour then apply it to the sand-through. Needs a deft touch, but most can be made to disappear. With careful dry sanding, a sand-through can be spotted before sufficient coating has been removed to make a difference and when re-coating the sand-through is totally invisible.

At least as well (no fillers/thickeners).

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

Same here, Fred. I have a mahogany guitar here at home that I finished two and a half years ago. It was beautiful then, but has some considerable shrinkage now.

"I think that you think that a certain something is not all that it could be, when, in fact, it is all that it should be... And more!"
"I'm sure it is."
"Look, you don't understand. There was shrinkage."

....from the Seinfeld episode "The Hamptons"


Pat

_________________
There are three kinds of people:

Those that make things happen,
those that watch things happen,
and those that wondered what happened.