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After sanding the Z-poxy ,it felt really smooth, I could see lines and ridges but couldn`t feel them.Any way after 3 coats of master gel as in Obriens video I can still see faint lines.I called Lmi and they said if it felt good I should be okay.I`m wondering if the lines will dissapear with enough coats of finish.Also how many coats of master gel can a person apply in a day.Any help is appreciated this is obviously my first guitar.        Thanks James W B

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James W Bolan
Nashville Tennessee

Welcome to the best of forums James!

First off ,thanks for all the welcoming.I can see how guitar building is a passionate endeavor.I`ve had quite a love affair with this first guitar.I`ll never be able to part with it.Anyway what I meant was I could see ridges and build up from the epoxy if I held it in the light just right , but it felt perfectly smooth.Anyway I`ve got about five coats of gel varnish on it and I can still see faint lines, but they seem to be getting less visible.I guess the big question is will they finally disappear with enough coats of varnish.Also how many coats are too many.After each coat I`ve checked the tone by tapping and I can`t tell any difference in sound.Anyway thanks for replying ,and I have checked the archives but can`t seem to figure the best way to proceed from this point.And to you Hesh I`ve got a Daughter in Ann Arbor who is expecting my first grandaughter in November.She says my next project is a crib, chest of drawers, and a changing table. After that back to guitars.        Thanks James W BJames W B38900.4260300926

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James W Bolan
Nashville Tennessee

Hi James, and welcome.

Not haveing seen the guitar its hard to say, but I offer this - if you can see ridges, but not feel them, then they are likely not in the finish, but in the wood - your prep prior to finish application didnt get rid of them. its like small scratches - your hand cant feel them but you can see them - only sanding them away will make them go. I figure if you can still see the lines/ridges after 3 or 4 coats, they are not going away. Finish work is only ever as good as your prep. More than once a gutiar has been resanded when the lacquer showed something that in the white could not be seen.

You have two choices I figure - live with what you have, or sand it all back. Not pleasant, but thats reality in the guitar making world. I know a guy who had fractured some zircote on a cutaway, and he told me he would fix it up in the finish - I laughed to myself, because unless he planned to paint it solid, the finish will only amplify the way it looks. Finish rarely hides anything, it makes it easier to find.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

Welcome James,

I think I'm with Tony on this. Unless it's in the finish and a finish that burns in to additional coats the fininsh only amplifies what's already there. I'd take the sandback option and build up again. I think you need to sand the Z-poxy to what you see and not what you feel.

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Dave White
De Faoite Stringed Instruments
". . . the one thing a machine just can't do is give you character and personalities and sometimes that comes with flaws, but it always comes with humanity" Monty Don talking about hand weaving, "Mastercrafts", Weaving, BBC March 2010

Thanks for the input.I`m pretty sure they aren`t in the wood.I sanded to 600 grit and then wiped mineral spirits on it and it looked great.I could tell it was the epoxy because there were also little spots kind of like build up.It also seems that with each coat it gets a little better. We`ll see   
   Also as I was applying the epoxy across the grain I could see the lines being left with the credit card with each swipe.
                           James W BJames W B38900.6136111111

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James W Bolan
Nashville Tennessee

Yeah Hesh I have been to Ann arbor a couple of times and it really is a nice town.I enjoyed all the restaurants where people eat out on the sidewalk.It looks like I`ll probably be delivering some baby furniture this fall.It would be great to look up a real builder.Hey if that 1956 is your birth year I got you beat by 6.I`m gonna hit the shop and slap on another coat of finish.
                   James W B

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James W Bolan
Nashville Tennessee

Hesh I`ll let you know.Just finished coat seven.I`m thinking it`s going to be okay.

                        James W B

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James W Bolan
Nashville Tennessee

Thanks ToddStock.That squeegee sounds lika a good idea.I have`nt decided yet but I`m leaning towards re-doing the top.James W B

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James W Bolan
Nashville Tennessee

Well I solved the problem by sanding all yhe finish off the top and back.I sanded down to the epoxy and kept sanding until visually it all looked the same.The neck and sides looked great the way they are.I didn`t have a squeegee but I had a grout float that worked great on a couple spots that got sanded down to bare wood.I appreciate all the input,you guys are great.Another thing I would like some input on is how deep should the saddle slot be.One person says within 1/8 inch of the total bridge depth, another person says at least 5/16 inch deep and another says half the height of the saddle,which is 5/32.I did the last suggestion but it seems like the saddle sits up pretty high. any suggestions?            Thanks James W B

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James W Bolan
Nashville Tennessee

Hummm?.....first off, after filling I sand back to "JUST" to the wood but no further. This leaves the pores filled but no film thickness on top of the wood. The I mix a 40% alcohol x 60% Zpoxy mixture and using a linen cloth I rag on a "very thin coat" only for color, and I an ready to apply the seal coat of shellac before going to finish.

I suspect that the lines you are seing are in the excess film still on the body and are deeper that the level you ave currently sanded to.

MichaelP, I adopted your method some time back and was curious, on the 60/40 thin mix, do you coat the top with this or just stick with the shellac only? I have only used it on the B&S on my last two.

Mike
White Oak, Texas

Spruce and Cedar top I use only shellac. hardwood tops like Koa I use Zpoxy because they need filling as well. I have done the 60/40 wipe and full strength on Spruce, but It is really just a waist of zpoxy.

Thanks Michael, one I have going now has some really dappled high figure Bearclaw and I have put a coat of shellac on it. I was just wondering on the Bearclaw if it would pop even more of the grain.

Mike
White Oak, Texas

probably would and I see no harm.

It was late last night when I responded and just pure passed on the fact that you have put shellac on the top already.........Don't put any Zpoxy over shellac or you will likly have adhesion issues. Zpoxy does not ad heare well to shellac at all.MichaelP38903.3931828704

Michael,
I am a bit confused about your comment " don't put Z-poxy over Shellac, it doesn't adhere well". That being the case...aren't you going to have adhesion problems putting Shellac over z-poxy? I know this has come up before in a similar thread but it just doesn't make sense to me. Please explain.


As far as the Saddle depth goes...several factors are at play:
1) Action desired
2) thickness of bridge relative to action desired
3) brake angle of strings over saddle

In one of Dan Erlewines videos ( they are all great by the way) he speaks of the 50/50 rule. Stating most manufaturers try to have the saddle 50% in the bridge and 50% out. That's what I try to do. Sometimes it's a little more or less depending on what is needed in the above three variables. I think your main concerns are having so little in the slot that it cracks the bridge, or having too thick a bridge so that you have poor brake angle and therefore the strings don't drive the top well...poor tone, sustain.

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Dave Bland

remember...

"If it doesn't play in tune...it's just pretty wood"

I know we have hashed this over time and time again. But shellac has not problem adhering to epoxy. However epoxy does have probems adhering to shellac. Shellac seams to adhear to darn near anything but epoxy is picky

MichaelP and Dave,

Not to worry!

I had remembered the thread where the Zpoxy over Shellac was a no-no and did some Archive searching. If I decide to do it as an experiment, I would sand back down to wood, use just the 60/40 mix. I am going to try this on some cheap Sitka tops I got for experimenting things with and on.

Thanks guys,

Mike

[QUOTE=MichaelP] I know we have hashed this over time and time again. But shellac has not problem adhering to epoxy. However epoxy does have probems adhering to shellac. Shellac seams to adhear to darn near anything but epoxy is picky[/QUOTE]

Michael,
do you think lightly sanding the shellac with say 400 grit paper would help the epoxy adhere to the shellac?

It may but I just don't think I would depend on it with out several test first. I have sanded shellac off and then filled with zpoxy and did not have any failures.

Cindy Burton tells me she uses a very common brand of 5 minute epoxy (I forget the brand name) for pore filling after sealing with shellac, and gets excellent results with no adhesion problems. She said many epoxies won't adhere to shellac, but some will.

After the 5 min epoxy pore fill (which, by her method, leaves extremely little epoxy on the surface), she goes on to FP the instrument.

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Todd Rose
Ithaca, NY

https://www.dreamingrosesecobnb.com/todds-art-music

https://www.facebook.com/ToddRoseGuitars/