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I thought I'd get a new thread going on the pore fill I have going on a mahogany/cedar guitar. I have applied two coats of epoxy and sanded between coats. The first coat was leveled with 400 grit wet paper. Took way too long and too messy. At Ricks suggestion I dug out the DA and cut it down with 500. I did the neck by hand so I could have better control of the cut and speed. It is looking very nice and I have no open pores, just nice level epoxy. Now I have this question for you seasoned West users. I have spots that I cut through to bare wood and wonder if I should spot apply, re-apply to the whole body or just seal the whole thing and spray clear. Rick? You here? Would the McF. rosewood sealer take care of these cut throughs? heres a shot of the leveled back and neck.

Hmmm, the back didn't make it on the first go.

Cutting through doesn't seem to matter.   The McFadden sealer has the same wetting properties as the epoxy. I wouldn't bother going as fine as 500; use 280 or 320 and get the job done faster. That will also give a bit of mechanical bite for the sealer.

Thanks Rick! That's just what I was concerned about, whether the sealer would wet the wood uniformly. I am surprised that we can get away with 320 or even 280! In automotive, the lowest we could go is 500 on a mechanical orbit, even then we had to be careful. I guess these epoxies and polyesters can actually fill the abrasions far better than the catalyzed urethanes. I like this West stuff!

I tell ya' what else. I LOVE the neck just in sanded epoxy alone! It feels very nice and playable. Thanks for the input too Hesh! Y'all rock!

With wood people tend to go to too fine a grit. You really shouldn't sand to any finer than 220 on wood unless you're going to do an oil finish.   The finer grits tend to burnish the wood and that prevents the finish from sticking well to it.   Between coats with poly (if I need to) you don't have to go any finer than 320.   I'm into being careful and working quickly.   The rougher grits don't load up as quickly, either.

The wood was sanded to 220 but I did use the 500 on the epoxy. Didn't load the paper (3M gold) Seemed to sand quite fast, lots faster than the wet 400!

You really don't want to leave an epoxy film on the guitar. You want the epoxy (finishing resin) in the pores.

I think this is one of the biggest misunderstood parts of filling with a finishing resin epoxy. You, or at least I don't want a noticeable film thickness on the wood. I sand back to bare surface every where leaving the finishing resin (epoxy) only in the pores. After the fill is cured and sanded back to wood, I make an ounce of 40% finishing resin (epoxy) and 60% alcohol and lightly rag on just to even the color. Keep in mind that this is 40%/60% mix is so thin that it is almost all absorbed into the surface wood fiber, leaving an even wet appearance. That one ounce should be more than enough to cover the back, sides and neck.

I have two guitars that will be filled this week or weekend. I will do a photo tutorial.

[QUOTE=MichaelP]You really don't want to leave an epoxy film on the guitar. You want the epoxy (finishing resin) in the pores. [/QUOTE]

 

Hmmm. That would explain how some finishers are getting by with one coat of the epoxy. It would seem that I am creating too much work here?

[QUOTE=MichaelP] You really don't want to leave an epoxy film on the guitar. You want the epoxy (finishing resin) in the pores.

I think this is one of the biggest misunderstood parts of filling with a finishing resin epoxy.
I have two guitars that will be filled this week or weekend. I will do a photo tutorial.[/QUOTE]

Well this is one tutorial I am really looking forward to. Thanks Michael.

Cheers

Kim

Sorry to sidetrack, but have you seen the new small packaging for West System? I just noticed this in the new Rockler catalog and it looks ideal for our application. West System Epoxy

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Don Atwood
Arlington, VA

I'm also very interested in a tutorial...thanks for all the info already posted!

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http://www.PeakeGuitars.com

I'd be curious to know how Rick is using the epoxy? Pores only or a thin film over most of the wood?

Joe, Rick covered all that and more in the other pore fill thread. 

Good point.  As I recall, he sands back, not worrying too much about if there are a few splotches left.  Then he uses the McFaddens(SP?) Sealer which has the same wetting properties as the epoxy.  This evens out the "wetness" look of the splotches.  Then shoots his finish.

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

Mario,

What ChemCraft product do you use in place of the McFaddens EIR sealer? Or do you just use the McFaddens product? I am wondering where these are available in Canada. Would Mohawk have these?

Shane

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Canada

[QUOTE=grumpy]Joe, Rick covered all that and more in the other pore fill thread.  [/QUOTE]

Well, not really. I've read through that one and even printed it all out to add to my own finishing manual and while he does mention cut throughs and patches of West not being an issue with him, I am curious as to what his feelings are on leaving a thin and level film with only few, small cut throughs. I know some of this might be redundant to those of you that are more familiar or experienced with West pore filling but I have to think that others with little or no experience with Wests epoxy fill might benefit from Ricks and others experience with it.

Grrrrr, need edit button.......... To simplify, I really would like to know if Rick has a preference. Level all the way back to wood with only pores filled or level but try to leave a film over most of the surface?

Shane, I put gave all the part numbers and product names in the lacquer thread <bg>

sorry, but I'm just not going to run back to the shop with pen and pad again....

Yes, I use the Chemcraft sealer(Isolante), ad Chemcraft polyester. The McFadden's was great, and it was doubly great having the exact same stuff as Rick so I could follow his exact instructions, but importing it was a pain, an costly. Chemcraft have several Canadian distributors.

No idea if Mohawk has anything similar. I see no need to look further.

Mario, I would be curious about the Chemcraft Polyester and sealer since I have not committed to any particular clear or sealer as of yet. still waiting to hear back from Neil Wooler from McF. on what quantities must be purchased. I'm afraid that I will be looking at 5 gal containers most likely. can you get smaller batches of Chemcrafts stuff?

I knew I read it in one of the threads.  This quote is from the "Pores Shucking Grain Filler" thread.

Rick Turner said, "I do not use a thickener because if you don't sand absolutely to wood,
it colors spots of epoxy film left on the surface.   With no filler, it
doesn't pore fill quite as well, but we don't have to sand as
carefully, either, and the sealer wets exactly the same as the epoxy.
"

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Waddy

Photobucket Build Album Library

Sound Clips of most of my guitars

My preference is to forge ahead and not worry about patches of epoxy and bare wood. The McFadden rosewood sealer seems to have exactly the same wetting properties as the epoxy. I say "seems" because if I'm proven wrong in the future, I'll change my finish schedule to suit, but for now, this works like gang busters.

A lot of the finishing process (along with everything else in lutherie) is knowing what makes a difference and what is simply self-indulgent navel gazing time wasting bulls.... I don't do this stuff as a hobby, though I love doing it. I build guitars for money, and I'd like to make more money than I am.

When I adopt a new technique or new material, the potential financial reward is a part of that decision making process.   That doesn't mean cheapening my guitars; it means delivering more bang for the buck in less time, and it has to tip toward being financially viable and profitable.

I'm doing the epoxy fill thing because I think it makes for a better finish in less time with less expenditure on finish materials. I'm not going for 100% pore fill with the epoxy as the sealer and polyester I use takes care of that last 10% to 20% just fine. To do a second fill and to do an epoxy wash coat are not good use of my time as I see it right now, and they will not improve the look.

To me this is like the whole thing of sanding with Micro Mesh to 3,600 grit...I'm sorry, but that is such a waste of time...Let's get this job done quickly, folks...It's not that much fun in the first place...

[QUOTE=grumpy] Shane, I put gave all the part numbers and product names in the lacquer thread <bg>sorry, but I'm just not going to run back to the shop with pen and pad again....Yes, I use the Chemcraft sealer(Isolante), ad Chemcraft polyester. The McFadden's was great, and it was doubly great having the exact same stuff as Rick so I could follow his exact instructions, but importing it was a pain, an costly. Chemcraft have several Canadian distributors.No idea if Mohawk has anything similar. I see no need to look further.
[/QUOTE]

Thanks Mario, that's all I needed. I didn't expect you to run for numbers! I have chemcraft products in my shop now and get them in Vancouver. I will follow up with them.

Shane

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Canada

[QUOTE=joe white] Mario, I would be curious about the Chemcraft Polyester and sealer since I have not committed to any particular clear or sealer as of yet. still waiting to hear back from Neil Wooler from McF. on what quantities must be purchased. I'm afraid that I will be looking at 5 gal containers most likely. can you get smaller batches of Chemcrafts stuff?[/QUOTE]

Joe:

I'm NOT answering for Mario, or anyone else for that matter. Those guys know their stuff.

But I did call Chemcraft, actually several different Chemcraft locations (including the Port Hope plant where the stuff is manufactured), and I was told that Chemcraft is only available in the States in minimum quantities of 25 gallons...UNLESS, one can find a distributor that regularly orders/stocks that amount and is willing to divide it. I called 3 distributors in my area, and none stock it at all. 25 gallons is costly, as Mario said, and the sticker shock is considerable, even on small quantities. In contrast, McFadden's will sell in 1 gallon minimums. I have all the Chemcraft product numbers, and mix ratios should you want them.

Just from my research, the Chemcraft products "seem" (to me only) to be preferable (the customer service/dialogue was certainly superior) to the McFadden's...but at those quantities, it's a slam dunk for the McFadden's. Their mix ratios appear to be very similar, but the Isolante sealer can apparently be sprayed over within about 20 minutes. Can't beat that.

I'm going to give the Poly a try at some point soon. Based on Rick, and Mario, and Kevin's advice, it's well worth trying.

Bill

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