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A couple of rosette’s and a rant.
http://w-ww.luthiersforum.com/forum/viewtopic.php?f=10102&t=9142		 Page 1 of 1
Author:  Rod True [ Thu Nov 02, 2006 4:34 pm ]
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Well, I'm not very happy at all with the way this Celtic rosette is turning out.
I certainly don't like the epoxy. It's not getting hard enough. I've let it set now for 4 days, shop temperature is 22*C (72*F) but I can still quite easily indent my thumb nail into it. I would think that it should be harder than that. When I mixed it, I was careful to mix 1:1 as the container stated. I'm using the G1 epoxy from Lee Valley and it says to use it at or above 20*C so I should be good.

Anyway, I've been working at leveling the rosette and the epoxy is curling up on me. If I sand it, it smears and leaves big holes. If I use a scraper, it gets to hot and pulls it up.

Needless to say, I'm very disappointed with the whole thing and really feel like throwing the top at the wall. I haven't done that yet, but getting closer.

To boot, since I've tried to level this thing out so much, I've sanded through some of the gold on the MOP and now it's a white and gold MOP rosette instead of all gold .

Anyway here it is, in all it's ugliness. I think I will call up Andy and get another one, route this one out, inlay it properly and fill it all with ebony dust and CA.



And here is the spalted maple rosette. I'm 99% happy with that one.



I also started to bend the sides for the curly maple guitar. It cracked on a figure line in the upper bout. I did a very light spritz (the wood sucked up the water really fast) wrapped it in foil, sandwiched like so, ss wood blanket ss got it up to 275*F (could be my thermometer is bad though) and there was steam coming off the sides and it almost smelt like burning wood, so I did the waist first to about 75%, than the upper bout, than the lower bout than the rest of the waist, than I noticed a nice sharp break at the upper bout. #%$^&*$#

Time to build a new bender and get a good thermometer and maybe take some side bending lessons.

I feel like giving up

I'm going to go eat and drink now.Rod True39024.0282523148
Author:  Shane Neifer [ Thu Nov 02, 2006 5:06 pm ]
Post subject: 
Rod,

You have an epoxy problem. My thoughts, the product is old, the proportions are not quite right (it is not that sensative though) or the 'black' has impacted the glue. I have used Cold Cure and now for the past 15 years have used West System and have never had it be anything but HARD.

You could try dropping some of the hardner on top but I doubt it will work Also, if it does not dry then you have a mucky mess to clean off the top.

I hope you get it figured though!

Shane
Author:  WalterK [ Thu Nov 02, 2006 6:29 pm ]
Post subject: 
Rod...Rod...Rod,

What am I going to do with you??
These 2 rosettes are magnificent brother. You can throw either one you really don't like my way.
It must take a lot of patience to produce something that artistic.
Just beautiful.

I would love to have this ability.
Due to my failing eyesight and diabetes, there is no way I can attempt this skill you have.
Enjoy them.
Kind regards,
walterWalterK39024.1047685185
Author:  Sam Price [ Thu Nov 02, 2006 7:00 pm ]
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Believe it or not, I had EXACTLY the same problem with my wooden Celtic Rosette...carving out the recessess by hand doesn't gaurentee a flush or even coloured surface when done.

Machine or by hand...it ain't easy.

I don't think I'd have it any other way. My main subject matter for woodcarving are Celtic knots anyway; it's wonderful bringing a 2D image into 3D...so I did not sweat it much when my rosette wasn't flush. (the Yamaha APX series have raised rosettes)

Celtic knots work extremely well when there is the illusion of 3 dimensional elements, either through shading or relief.

Your Celtic rosette is incredibly clean looking and beautiful from where I'm looking. All I can see is tonal changes; and to me that gives the rosette some wonderful contrasts. If it was just a plain MOP gold, it would look sterile and dull.

EDIT...LOVE the spalted maple too!!!

Sam Price39024.1276388889
Author:  Kim [ Thu Nov 02, 2006 9:38 pm ]
Post subject: 
Gees Rod,

Sorry about the epoxy drama mate, I really do feel for you buddy . I once spent for ever binding up a very expensive composite game fishing rod blank with the best components I could afford. Hours and hours of careful meticulous eye straining work, interlocking pattens of different coloured cottons upon a setup that had been sooo carefully planned out.

As is the process, the bindings were then locked in place by the application of heat thinned epoxy as the rod span on a slow rotisserie. I had made my mix with the caution and respect that the job deserved by weighing out the A & B parts carefully.

As with your experience the epoxy never did harden. As a result the bindings became opaque as the epoxy clouded over time being that it was so susceptible to sun damage and scratching. You could even pick it off with your fingernail like some form of mutant silicone sealant

That was about 15 years ago, and I remember feeling so angry at the time that if I had been able to get my hands on the chemist who was responsible for that faulty product, I reckon I could have done something to him for which I would be just about getting out of jail for now .

Now, when ever I buy a new batch of epoxy, I make a small test mix to be sure, tis cheap insurance. And weigh, always weigh.

Peace

Kim
Author:  PaulB [ Thu Nov 02, 2006 10:46 pm ]
Post subject: 
Put it on the shelf and make another. You should be able to pick it up in a month or two and be good to go. If the epoxy has set up hard enough that you have to dig your thumb nail into it to make a mark, then it should set up all the way with time.

You just need to wait until the cross-linking is complete. The epoxy is either old or you got the ratio's wrong (who hasn't done that). In this case patience will solve the problem.
Author:  Serge Poirier [ Thu Nov 02, 2006 10:58 pm ]
Post subject: 
Rod, take a break my brother, it's one of those times where we push too hard so yes, enjoy a good lunch, play with your kids, give attention to your spouse, listen and play some music for a while and while watching TV one night, the answers will all come to you on how to fix whatever doesn't please you right now.

We all go through this, i know i could lift any heavy power tool and carry it out of my shop alone when i'm mad but what good would it do to me, right?

To my eyes, your rosettes are very beautiful, let it sit for a while, it will all be good in the end.

My heart goes out to you and i'll be sending you very positive thoughts to help repell those dark clouds over your head, we need to keep you here for a very long time!

Serge
Author:  Glen H [ Fri Nov 03, 2006 1:18 am ]
Post subject: 
Rod,
I echo the sentiments above! Just set it aside and let it sit. Build another top and use this one for a different guitar. In time, I believe there is a good chance the epoxy will harden. In the meantime, work on something else. I will never forget when I was in Junior High, I build a skateboard out of wood (back then this was the only way to get a good skateboard) and finished it with varnish. I was so frustrated that the finish would not harden (I put it on very thick). After a few days, I threw the skateboard under the shop table and thought (or maybe said) a few cusses. A couple years later, while packing up stuff for our family move to another city and I found the skateboard. The finish was hard and slick as glass!
Anyhow, I understand your frustration, but now is the time for patience.
Author:  Rod True [ Fri Nov 03, 2006 2:26 am ]
Post subject: 
Sorry for the woe is me pitty party. What a goof

Thanks so much for all the encouragement and stories of similar woes, I know I'm not the only one to have ever experienced an issue in our hobbies.

After a couple of pieces of pizza and a beer and a good night's sleep, I'm much more calm about the whole thing. I will let the celtic top sit for a month or so to see if it gets harder.

See how it's pitting in the epoxy, this just keeps happening, so I hope it will harden more over time.



Anyway, thanks again my friends for all the support and encouragement, your all wonderfull
Author:  Kim [ Fri Nov 03, 2006 2:51 am ]
Post subject: 
Hmmm Beer, is there anything it can't do

Good to see your spirits up again Rod, and by the way it was ironic how I just described the binding of a rod to a Rod in a bind

Cheers

Kim
Author:  John How [ Fri Nov 03, 2006 3:23 am ]
Post subject: 
the set times for epoxy are probably for joints that fit tight like any wood joint. Of course your not using it that way but as a filler. Now I know I do the same thing sometimes and it seems that patience is the key. It will eventually harden and you'll be good.

As for bending maple, it's a skill that takes practice. I have broken them too and I have bent them without breaking them as well. It's not too bad if it's not a cutaway. Maybe just a bit more water than you used, It's a tough call though and one that takes practice. I would have bent the waist completely before bending the bouts. I know some people don't but with figured wood, why stress it after your bend is done by stretching it, which is essentially why you would leave the waist loose and finish with it. With curly wood you have grain that diving pretty much straight thru the wood so when it's hot and maybe wet, it'll pull apart fairly easy.
Author:  Rod True [ Fri Nov 03, 2006 5:24 am ]
Post subject: 
Thanks John, good info
Author:  Andy Zimmerman [ Fri Nov 03, 2006 5:31 am ]
Post subject: 
I have had the same problem with epoxy. To help it harden, I placed the top
in my oven at 175 degrees and let it sit there.   Low temp only.

Now I test my epoxy first. Mix a batch and see if it hardens. If it doesn't I
get new epoxy. My most recent rosette. (Posted above with "Hesh inspired"
I used cocobolo dust and superglue.

Good luck
Author:  old man [ Fri Nov 03, 2006 6:29 am ]
Post subject: 
Rod, did you try spraying some accelerator on it?



Never mind, I guess that is for CA.

Ronold man39024.6051736111
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