General Finishes Waterbase Topcoat - SM is pushing this - anyone tried it?

[Chuck Tweedy]

I've tested it with alcohol - but I'm not sure I'm up to the hot sweaty task

[Peter Wilcox]

All the finish manufacturers have technical people on staff to answer questions regarding their products, and they can help give suggestions and instructions for use. They can be very helpful, you just have to call them.

Apparently General Finishes Corp is not interested in answering any questions about their products, as I have found no way to contact them. No email. The phone # (414) 426-0194 is for messages only, and phone calls will not be returned. For questions about the products, "contact your retailer."

[Chuck Tweedy]

thanks for that info Peter. Anyone else ever tried to contact General??

[David King]

What I would like to know is how well it holds up to sweaty arms and bodies in the warm Summer weather. Otherwise all the specs and data I have read make it sound like a great finish for guitars and mandolins.

Michael, it holds up well to alcohol and acetone so I'm hoping that sweat won't be a problem. I had a customer who's sweat stripped a nitrocellulose finish in under a month. It always depends on the sweat.
I had a brush that had dried out and I left it soaking in a baggy of acetone for a week and was finally able to get the finish to break down but not dissolve. For a water based finish it's astoundingly resistant to water and cleaning products.

I've never tried to contact the company and it's possible that Thanksgiving week might have been a tough time to get hold of them for answers. I'd do searches for info via the many woodworking and instrument fora where it may have come up for discussion already.
Lots of random info here: http://www.mandolincafe.com/forum/showt ... ar-Caution

[Chuck Tweedy]

Okay people - I buffed out my sample pieces.
It was actually very easy to buff them out - I was shocked.
As far as preparation of these samples, I did not take great care to make them perfect. As a matter of fact I was doing it real time earlier in this thread, I was slopping the finish on with paper towel pads, and I sanded back with my cheap-ass papers (which leave the deep scratches you see). I sanded with 400, 800, 1200 - just those - and took them to the buffer. I have a big Stew-Mac arbor with 14" doubled buffs, and I use Menzerna medium and fine (both compounds are yellow/beige - whatever - they are old)
It is very difficult to take pictures of finish, but I think these shots show what they look like reasonably well.
The cocobolo sample has very little finish on it - I think it may actually be down to wood in the center. It still looks great. The area along where the sapwood transitions to heartwood has a reasonable amount of finish on it, and it is rockin' there.
The spruce piece has more finish on it, and it looks great. In person, there is a deep silking which is very attractive in the light.
This stuff is the bom - I'm using it for sure. I'll just have to avoid big sweaty customers.

[Michael Lewis]

Nice examples, chuck. Thanks for that. It really is looking good!

As for not being able to speak with the company, I'm really surprised. Is this a "fly by night" company, or have they been around for a while?

[Chuck Tweedy]

General has been around for a long time. I used one of their products many years ago when I build some furniture for my home. I do think it may be a holiday time thing.

[Mark Swanson]

If it polishes up that easily, it might be quite soft. Looks good Chuck!

[Chuck Tweedy]

Mark, it is - in fact - still a bit soft. I can mar the finish with my fingernail on these test pieces.
It has only been on there for about a week, and my shop is un-heated. In the frigid climes of San Diego, it can get down below 50F in here (yes, I know - shocking)
I'm assuming (perhaps wrongly) that since this finish has been designed as a Gym floor finish, that it will get harder than it is now - with time. It is a cross-linked polyurethane after all!
I still have some time before I need to put it on the guitar I'm building, so till I absolutely need to cut-bait and spray, I'll leave these pieces in the hot-box and see where we get in a couple weeks.
I think the good news is that it has that varnish look and feel. It adheres well, it sands well, it buffs well. If it hardens up as it cross-links, then we're a GO.

[Bryan Bear]

Will there be any additional shrinkage as it cross links/hardens up? I'm wondering if you need to wait until it is harder to level sand and buff, especially since you are filling pores with it. I have no experience with water-base finishes so this may be a dumb question (like the other 1,000 I have asked here <G>).

[Chuck Tweedy]

Bryan, it cures by oxidation, like any oil-based varnish.
I'm assuming this stuff is the same, again maybe wrongly.
Oxygen curing varnish actually swell as they cure - which can cause problems of its own.

I think that once the water has dried, and the small amount of organic vehicle that is in this stuff flashes off - it will stop shrinking. So far the test pieces have shown this property.

[David King]

EnduroVar is about 20% solids by volume according to the PDF. Better than lacquer but nothing like the 30-50% solids of the better 2k and 3k polyurethanes or the 90% of a polyester finish.

[Chuck Tweedy]

Status Report: Test pieces have been in the dry-box for the past few days, and - as expected - the finish has hardened up significantly.
I can see places where I was able to mash the finish with a fingernail before, and right next to to those sames spots, I am not able to damage it now.
Also, the finish has shrunk back into the pores a bit - so I will be waiting longer to sand back on the real thing.
Still looks great, but the ultra-thin areas of the coco piece are now more noticeable - which is expected since the finish has shrunk and hardened.

[David King]

My rule with this would be to get all the coats on along with a couple of extra coats so that you don't need to go back in with more finish after the first coats have cross linked and you happen to burn through.

[Chuck Tweedy]

Yep - sounds right to me.

[Michael Lewis]

Is there a time window after which it doesn't buff well? Some of the old water borne finishes were like that, they got too hard after a few weeks. (how could a finish be too hard?)

[Chuck Tweedy]

It is getting much harder now - no idea if it would still buff.
The schedule that SM has for "High Performance", which is very similar stuff, says wait a week before buffing.
That is exactly what I did with my samples and they buffed very well.
The challenge will be to have the finish shrunk back enough before final sanding and buffing - and still have it buff-able. I think it will be buffable, just not as easy as with the sample pieces.

I feel like I'm at work

[Randolph Rhett]

I'm very interested in your progress. I love to FP, but as I commit to building guitars for others on a timetable I'm struggling to find the time to build up a base. I gather building up with this stuff has been very quick and easy. Level sanding in just two hours? Apply with a foam brush? Buff easily to a high gloss a week later? Sounds almost too good to be true.

To summarize the problems you've had, it shrinks even after one week. However, the fear is that if you wait longer, will be too hard to buff. Also, I imagine though no one has said, that of you wait a couple of weeks to see of it stops shirking and you decide you need more coats the subsequent coats won't burn into the now cure bottom coats.

Is that a fair summary?

If so, what are your thoughts about overcoming this issue? Do you think a carefully leveled epoxy pore fill would make the shrinkage a moot point?

[Chuck Tweedy]

Randolph, yes I think that is a fair summary - thanks.
I plan on following the Stew-Mac finishing schedule - see HERE

I'm not concerned about some pore shrink-back - I think it gives the finished instrument a more "honest" look.

My main concern is to get all the finish on at a reasonably fast pace, because - as you said - with too much time between coats it will not burn in like lacquer or shellac. After that, I have good polishing tools (micromesh abrasive discs and 14" buffer), so I'm confident that I can polish it up even when it is quite hard.

[Michael Lewis]

Chuck, how long ago were your wood samples last coated? You said they buffed very easily, but now I wonder if you fine sand them will they still buff out after two weeks or more?