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A couple months ago I decided to give UV finishes a try. I've seen some really nice finished done with it, it's tough stuff, and can go on very thin. I really thought it was going to be fast, great, easy. So I ordered the CureUV system. Following the directions to the letter, I wrecked a guitar. Trying to cure the drips on the back, the heat from the light freed up the glue in the backseam and it started to open. Got it closed up, but you can still see it. I'll get back to it one of these days.

I read Zlurgh's recent thread and wondered what had I done? I felt you guys pain, but felt too stupid to comment. I tried brushing on one surface at a time and that didn't work either. Had adhesion issues. Wrecked an uke this time. Luckily the stuff sands off really easily. As an added bonus, my shop has never been so clean, I'll bet there was not even a speck of dust on the floor by days end.

Shortly after that shop disaster, while at the Healdsburg Festival, I stopped by the Cardinal Finishes booth and talked to their chemist, Mac, for about an hour, mostly about their UV gloss finish system. They use a pre-cat sealer, gel pore fill and gloss top coat that has solvent in it so you can apply several coats before lighting it up. He explained to me that they designed their UV gloss to spray like lacquer, so it would flash right away. Mac offered me some samples if I signed up at the show. So of course I signed up. After a couple emails and phone calls the samples were on their way.

When I got home this afternoon there was a box on my porch from Mac, with the sealer, filler and UV gloss. I was thrilled to see a trial size of their gloss lacquer as well. I've been hearing good things about it.

There weren't any instructions to go along with it, but I have the other brand's pretty well memorized, and the gloss is supposed to spray like lacquer....how hard could it be? I built an uke just for the purpose of trying this out, out of sapele and spruce, so it was ready for finish already. That was 4 hours ago (ok 5, I type slow)

I shot two coats of precat sealer about a half hour apart and let it dry for about an hour. Wiped on the gel filler and hit it with the light. It sanded so easily, I really should have left more on, or applied another coat as there are a few pores left on the back. Then I shot a coat of the UV gloss. It went on perfect, no problem, probably easier than lacquer. Then it flashed right over...no dust, no nibs! Shot two more coats about 15 mins apart, hit it with the light. I'd be surprised if the top finish thickness is over .002. I was so so excited about how good it looked already, I cut up some new micromesh and wet sanded up through the grits. Took about 20-30 minutes to go from 1500 to 6000, this stuff sands very easily.

I clamped my buffer in the vise and went at it with Mezerna Medium and then fine. The cheap chinese belt on the buffer stretched some this summer so I couldn't put much pressure before it started to slip. I'll fix that tomorrow.

Here are some pics of the finished uke. I am SO pleased, excited, thrilled, impressed..... This product actually WORKS! Four hours from box on porch to finished uke. I'm calling Mac tomorrow to get the instructions. No dust, no nibs, no learning curve.




Steve

Impressive! Congratualations on finding a system.

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Jim Watts
http://jameswattsguitars.com

Thanks for the review! I was very close to ordering the CureUV package before reading some of the reviews. Did you use the light from CureUV for this finish?



Matt

WOW! A 4-5 hour finish from sealing to buffing?

Can you please elaborate more on the set up? (materials, equipment...)

Thanks for the great post!

Ray

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Guitar Building = Continuous Improvement Process

Thanks for the nice comments.

As to the CureUV light, it's great, although I have nothing to compare it to, and I am now very happy I invested in one. As to the CureUV finish itself, just because I couldn't figure out how to apply it successfully, might say more about me than about the product. Maybe if I had a clean room and a robot..... The Cardinal UV worked so well for me because it sprays like lacquer, and I'm used to spraying lacquer.

There isn't much to elaborate on. 4 stage Fuji turbine and gravity gun to spray ( outside, with the shop to shade the wind ). Respirator. Today I wear long sleeves to spray because I don't think I should light up the overspray on my arms. Tee shirt to wipe on the gel filler, sandpaper and block to level it. MicroMesh and Mezerna for the final glossing up.

I've emailed to get the 'actual instructions', and if they're different than what I did, I'll post them. Today I'll try it on a koa tenor that was going to get lacquered and I'll try to pay a little more attention to the weight and film thickness when all is said and done.

Steve

Steve,
Thanks for all the great info. Sounds too good to be true!

I called up Cardinal and spoke with Mac.
He was very helpful. Basically reiterated the process as you stated.

He said there are two types of sealer pre-cat (vinyl) and post cat (urethane).

The post cat has a catalyst-pre cat does not.

My question is where do you get the UV lights? What type? how much?

Regards,
Brad

Steve,

Sounds great! Thanks for your report. I'll have to give Cardinal a call and get some in here ASAP! If I'm lucky, they may be open tomorrow morning - they are local to me here!
I have a business card from George Ball of Cardinal who I met at Healdsburg and had a great chat with - how are George and Mac related business wise, do you know?

Did you spray the 3 top coats on the whole instrument in one take (rotating it as you went)?
Did you use an HVLP conversion gun, an HVLP turbine, or just an ordinary spray gun?
Did you strain the material at all or just use it neat straight from the can?

I'm very encouraged to hear of your success with this material - I'm sure Pat will be too - I'll give him a call an point him at this thread if he doesn't pop up soon!

Cheers,
Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

Yup, Mac is a great resource. As I understand it, he is a chemist for the company. I didn't get to meet George.

For lights I use the CureUV Powershot 1100 handheld from SPDI. http://www.cureuv.com/total-cure-uv-pow ... e-pak.html . It seems like a fine piece of equipment, but I know little about UV in general, and nothing of the differences between the products available. I'm glad I got it. Dave, do you have a light already?

My spray rig is a Fuji 4 stage turbine Super4 Gold with a Fuji HVLP gravity gun. I sprayed one coat at a time about 10 minutes or so apart. Didn't see a need to strain the material as it is still nice and clean. I do strain lacquer, and if the UV Gloss ever looks like it needs a strain, it will get one.

I cut the finish with 10-20% acetone. Mac said that was fine, but butyl acetate would be better. I was fresh out of butyl acetate.

So I finished a koa tenor yesterday and, and, and......my wife said it best. I showed her and just said, " wow, wow, woooow." And it went on thin. Measured at the soundhole the finish is .003". Two coats of pore fill and 3/4 coats of finish on a tenor uke weighed in at 11 grams. That's considerably less than I've been able to achieve with other finishes.

Buffing. Not bad at all, but way different than lacquer. I'm a total wuss when it comes to buffing nitro, especially at the edges. For the UV poly I took the 12" domet wheels off and put the 14" cotton flannel wheels back on. I really had to lay into this stuff. As it started to gloss up, I noticed some areas near the edges that looked dull. I couldn't really tell if I went too far, or not far enough. I knew this stuff is supposed to be harder to buff through, so I layed into it around the edges at an angle that I personally would never try with nitro. It buffed up great, I didn't go through.

I really want to try the Cardinal nitro....maybe just one more with the UV first. Dave, I think you're gonna love this stuff, and if they are open this morning, I look forward to your review this afternoon.

Let me apologize in advance for the gratuitous 'look what I did today' pics. I really am (for the most the most part) trying to show the finish.

Steve

Thanks Steve! The finish on your uke looks fabulous - a real mirror finish!

I have the same UV lamp as you. Pat an I bought them about the same time and we've been struggling to make the Cure UV finish work for us. I have a small booth from UVIII also, but the lamps are not powerful enough and I've not been able to use it to finish a guitar yet! Not sure what I'm going to do with it - maybe retrofit some more powerful lamps?

I've tried another couple of UV finishes in addition to the Cure UV stuff but I'm not happy with any of them. So, I'm REALLY looking forward to trying the Cardinal stuff!! Unfortunately, the Cardinal office is not open today I'll have to wait until Monday.

Thanks again for sharing your experience with us Steve - you have no idea how nice it is to hear that success is possible with the Cardinal material!!

Cheers,
Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

Yeah...I'm certain if you can stack three coats of topcoat prior to hitting it with the light you're going to be happy with it. I'd of gotten much further with it myself if that was possible. Even so....I'd still need a functional curing booth in order to make it work for me.

My only remaining question with the Cardinal stuff would be to ask about and then test the adhesion between the pre-cat sealer and the gel filler....to see if there is a molecular bond taking place. That would cinch it for me.

I'm still disgusted with the CureUV stuff. After 6 months there is still sealer leaking out of two guitars. I expect they are ruined....pretty demoralizing.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

I feel a little better now, I only wrecked one guitar and one uke with the CureUV stuff. I didn't have the sense to send it back, I stuck it in the cabinet with the other latest greatest that doesn't work. I seriously thought I was just too lame to make it work.

I stripped the guitar and am recoating it with the Cardinal today. Fingers crossed. Looking forward to Dave F's review on Monday.

So is there a less expensive way to cure the Cardinal products than spending $2K on the CureUV equipment? It sounds like many of the UV cure manufacturers make their products so that only a certain UV light can cure them, and I assume that's so they can make more money selling the equipment. What appeals to me about the UV products that can be cured in sunlight (e.g., Solarez) is that inexpensive generic tanning booth bulbs can be used to build a curing booth if you want to go that route.

OTOH, I wonder if one can purchase just the bulbs required to cure the Cardinal finish, which might save some money.

I remembered from another thread about this stuff: http://www.solarez.com/productsnew/photiIsm.html

Sounds like this should turn any "Unsaturated Polyester Resin" into a sunlight curing version no? Is the Cardinal stuff "unsaturated Poly"?

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Ah ha! I had not thought about using the Solarez photoinitiator in another resin. I don't know whether Cardinal's is unsaturated but I will find out. Thanks Andy!

I just found out that that same gloss poly can be chemically catalyzed as well. 24 hour cure. Wow.

Steve

Nice!

How did you order the gloss poly? I would like to order some but I didn't see a way to do it from their web site. Do they sell direct, or do I need to find a distributor?

At healdsburg I signed up for a sample quart. 4 ukes and a guitar later the quart is almost gone. I've just emailed them to find out how to order some more. When I find out I'll let you know.

Steve

Oops - you said that in your original post and I'd forgotten about it. Sorry 'bout that.

Thanks Steve!

Just got back from a few days in the Toronto area. Thanks for posting this Steve. Very impressive and I'll have to give the Cardinal coatings a try if they'll send me some samples as well. One question I have though (I briefly went to their web site and it was skimpy on information) is how is this product in terms of dangerous volatiles. For all its shortcomings, one thing the cureuv.com finish does have going for it is zero VOCs so I could use it without too much fear of chemically poisoning myself. It was for this reason, that I also intended to try out the Admiralty Coatings, but they don't seem interested in sending me sample sizes and I'm reluctant to spend $600. to do some tests. I would also want to know if I could brush it on since I don't have a spray booth.

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.

Hi Pat, the data sheet says 67% solids, but for the life of me I can't figure out how to attach a downloaded pdf. I'd be happy to forward it via email if you want to pm your address. Here's the best I could come up with... a couple pics of the can. BTW I tried the methods you outlined for the CureUV gloss. I just didn't seem to be able to get it, but thanls for posting it.

Steve

Cardinal responded to an e-mail inquiry I sent and included the attached PDFs, which include the data sheets for the gel filler and clear coat, and a finish schedule. I thought I would share it with the group...

I ordered some Cardinal UV material (pre-cat sealer, gel filler, gloss finish, thinner) today Should be here in a couple of days, yay!!

Cheers,
Dave F.

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Cambrian Guitars

"There goes Mister Tic-Tac out the back with some bric-brac from the knick-knack rack"

Sweet! Did you order directly from Cardinal?

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I didn't mean to say it, but I meant what I said.
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Opps double post.

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I didn't mean to say it, but I meant what I said.
http://www.brackettinstruments.com/