WTF problems

[David Reed]

Not sure what I am doing wrong here. Applying the WTF to smaller projects is no problem, but I cannot get it to work well on a larger project. I have turned a platter about 18" diameter and cannot make a decent finish. I cannot get the towel marks out, either rotary if applied on the lathe or linear if applied manually. If I continue to work it until The marks flatten, it is too close to dry and leaves a rough finish. I even tried spraying it on with my airbrush, both straight from the can and thinned. Some areas come out perfect and others are stippled, appearing like it is beading upon the underlying finish (that would be cured WTF sanded with 400 paper).
What am I doing wrong? The product just appeared too good initially.
david

[allen thunem]

i am anxious to hear others thoughts on this as well

[Jim Burr]

This will sound stupid David, but I've found that more is better. I just finished a bowl where I just poured it in and washed it around with a towel...worked well for me but this was only my experience, it's not my fault it worked and others no doubt will say it's wrong...YMMV

[Roger Chandler]

Jim may be on to something here........you really need a wet line on the project for full coverage, or else the dryers in the WTF will evaporate the stuff so quickly you end up with not enough product to cover well. I had the same thing happen in the dead of summer when my shop temp was over 100 degrees......it dried too fast, and I ended up with a platter that I need to go back and get sanded back and reapply..........

I did mine on the lathe, turning at about 150 rpm...........you should soak your rag well........I like to use tshirt material and not the paper towels on a big project.......hope this helps!

[Jamie Donaldson]

I've also had difficulty covering larger surfaces with WTF, and spraying was the easy solution. Wiping takes too much time and leaves uneven surfaces, so the rapid drying is a handicap rather than an enhancement over the older High Performance finish which I also still use on larger works.

[David Reed]

Not surprised in the heat of summer, but this is in my 50 degree shop (too cold?? I did try hand application in the 70 degree living space; dried even quicker). I tried with the lathe spinning and end up with either too little product for coverage or the WTF spins of in a radial pattern, kind like those booths at the fair and dropping paint on spinning paper. Tried spinning the lathe slow, medium and higher speeds, all with their own trouble. Again little problem on smaller pieces. No doubt, largely operator error......
Thinking of sanding smooth again and using rattle can lacquer.........

[Peter Elliott]

For large projects, I would use a real good soft bristle brush to apply and then wipe with a clean cotton rag. You are not getting enough product on with just the rag. I would do one side at a time, allowing each to dry to touch. After your 1st coat, you should be able to apply with a rag, folded without lap marks.

Shooting it onto large projects like yours works best. HVLP with 1.0mm or 1.2mm tip

You can also start with a rattle can of dewax shellac, sanded well.. then onto WTF. This is a 1/2 cut of dewax shellac with almost no color. I'd only hit it 1 time and sand.

Depending the wood, dryness and shop conditions.. Wood can really suck up WTF pretty quick because it's thin. It also dries fairly quick but make sure you let it cure before hitting the buffing wheels.

[David Reed]

This troublesome application is over two coats of de waxed shellac, sanded with 400 paper. My trouble was not specifically lap marks as much as lines from the applicator cloth, and tried a few types of soft fine weave cotton as well as paper. Spray worked pretty well except the stippled surface, even when dry. I don't have an HVLP sprayer. Will give brushing a try and see try wiping back quickly and see what happens.

[thomas prusak]

IMO there are plenty of other finish options one can use, with much greater consistency than that of WTF. That is the conclusion I eventually arrived at after having had success initially, and many unsuccessful results using WTF. (general brand) to be clear.

[Leo Van Der Loo]

I looked what all is in it,lots of not to healthy material, and very fast evaporation, this WTF will probably work fine on smaller pieces where you can cover the whole surface before it is all evaporated.

I think I tried something like that many moons ago and wasn't impressed with it, however looking at the MSDS I'm glad I got away from it, done enough damage to me already :rolleyes:

Here's the part that made me think it isn't very healthy stuff to use :

248381

[Mike Cruz]

David, my experience with WTF is this: THIN coats. SAND every 3 coats. NO more than 4 coats between sanding. You can sand after 2.

Big items are difficult, no doubt because WTF dries so quickly. I have recently started using WTF on pens. I apply one drop (maybe two) on a small swatch of cotton fabric. While the lathe is running, I run the swatch from one end to the other. DO NOT try to go backwards. DO NOT try to touch up. That'll just ruin things. Immediately after application, I blow compressed air across the blank. This dries the WTF, but also helps flatten it out.

On HFs, I have had success, but again, on smaller ones...about 4" x 4". Some bigger... I'm really not a fan of applying it ON the lathe. It simply dries too quickly and you'll easily get lap marks.

Thin coats, sand after 3. That is how I've gotten my best results. BTW, I've used it on bowls up to about 12" or so just fine.

[Peter Elliott]

IMO there are plenty of other finish options one can use, with much greater consistency than that of WTF. That is the conclusion I eventually arrived at after having had success initially, and many unsuccessful results using WTF. (general brand) to be clear.

Agree with Thomas here... another good GF product is Arm-r-Seal... It's not talked about here much in the turning section but it makes a great wipe on product.

[Mike Cruz]

The only think I can think of that would explain everyone's initial "love" of WTF, followed by inconsistent results is user error.

When it was new, many pay a lot of attention to the process...following instructions and taking their time. Then, after using it a while, we tend to get a little sloppy...rushing, laying it on juuuust a little thicker to speed things up...we lose that intitial wide eyed patience we once had. And the finish no longer gives us the same great results.

I've had some really great results with WTF, and some okay results. I'm pretty sure that the product didn't change from one piece to the next. I know my tendencies, and I know what I did wrong.

WTF gives a great finish. You just have to do it "right".

Hey, CA gives a great finish for pens. People still have problems using that, too. You just have to know how to do it... Can't blame the CA.:rolleyes:

[thomas prusak]

Mike, I agree with you completely as to applying properly. For me, I just get better results consistently, with other finishes. The 'other' finishes are more forgiving and me being an expert in the field of inconsistent finishing results, benefits from said forgiveness.

[Mike Cruz]

I completely understand that. And I want to make sure that I'm clear... The larger the turning, the more difficult WTF is to apply. I just put it on a 13 or so inch bowl. The coats don't go on very smooth at that size. So, you have to sand back...often. The great part about it is that it is a nice hard and beautiful finish that can be applied and buffed very quickly...difficult to do with a lot of finishes as they need time to cure.

[Justin Stephen]

I have only had very limited experience so far with WTF, using it to finish a couple of ~10" deep bowls. I applied it using folded up blue shop towels, applying what to my mind was very thin coats every 10 minutes or so, beating it back with 0000 steel wool every 3-4 coats. I think the total number of coats was about 10. I have been happy with the results so far.

[Jon Nuckles]

Leo: The MSDS you posted appears to be for Behlen's WTF. I believe the original poster is using General Finishes WTF. It is new in the last year or so; maybe you missed all the posts on it while you were away.

[Mike Cruz]

Ah, yes, I am talking about General Finishes, too...

[Reid Strand]

The weird thing I've noticed about the lap marks when wiping it on thick is that when I just wipe a thick coan on quick, without going back and forth over the same section, the lap marks even themselves out in the drying process. The stuff does not have a high solids content. When I go back and forth and try to get an even film on, everything goes downhill.

The problem I have is that a thick coat on the sides of the bowl tends to run. Answer is to dip the rag, do the bottom of the bowl, and then after the rag has less finish in it, sort of wipe it up onto the sides. Not sure if that makes sense, but it seems to work for me.

[Peter Elliott]

Me too and Leo MSDS doesn't look right. It's a water based hybrid finish.

Last time I used it on a 9" bowl. I applied via cotton towel.. folded into a square. I use one edge of it like a brush. I load up enough WTF to soak 1/2 of the square folded towel.

I apply very quick and do not try to go back and forth. Especially the first coat.
I only do 1 side of a bowl at a time.
I sand at 320 with a foam pad
Additional coats go on much better after build up of previous coats.
Last coat I do not sand
I buff out after a few days of cure time over 65f room.

It is not a simple finish
Make sure it is mixed and if you have the can open a few times, I would strain with a fine mesh.

It sprays very well if you have a hvlp gun with a 1mm tip

All my sanding is very light, making a powder residue. Looking to de-nib. If you see scratches, 320 is not go to get rid of them.
Lap marks - you almost have to start over.

Like I mentioned, try Arm-r-seal. They sell it in a small bottle to try.

[Bob Vavricka]

I'm not familiar with this finish but I would check to see if there is a retarder available for it to slow down the drying time and give it a chance to level out some after application.

[David Reed]

Thanks for all the input. Today I sanded it all flat again, briefly with 220 then thoroughly with 320. Will give it another try as I have liked the results with Generals WTF on smaller pieces and let you know what happened.

[Leo Van Der Loo]

Sure looks like I was talking Oranges and you guys Apples :o :)

And no am not aware of a new (water based,carried??) finish, as the wood turners finish I knew about was like the one I got the MSDS on, sorry for the mix-up.

[Peter Elliott]

Leo, here is the MSDS.. had it saved and dug it up. As far as a health hazard, it's a 1.. 4 being the highest given. 1= slight hazard with "possiible irritation". Almost everything get's a 1 or higher, not seen a 0 unless it's pure water. Always wear a mask of some type.

248466

[Mike Cruz]

Hmmmmm. Water is a 0, huh? I bet that will be the new "best finish" in California...:D

[Leo Van Der Loo]

The other 30 t0 40% part is what you have to have a close look at, so most of the alcohols are gone, but things like trimethylbenzine even at low PPM should not be lightly dismissed, anyway I don't think I'm going to be looking for another troublesome finish soon, and thanks for the MSDS Peter, saves me digging for more info I don't really need :D

[Peter Elliott]

Well I had to go look... from OSHA


Summary of toxicology

Effects on Animals: Trimethyl benzene is a skin irritant and also affects the lungs and central nervous system in experimental animals [ACGIH 1991]. The oral LD(50) in rats is 8,970 mg/kg [NIOSH 1991]. Instillation of trimethyl benzene into the lungs caused chemical pneumonitis at the site of contact [ACGIH 1991]. High concentrations of trimethyl benzene vapors cause central nervous system depression [ACGIH 1991]. During a 24-hour exposure to 2,400 ppm of the 1,3, 5-trimethyl benzene isomer, 4 of 16 rats died of respiratory arrest [ACGIH 1991]. Rats exposed to 1,700 ppm for four months had reduced body weight gain, central nervous system depression, and increasing lymphopenia and neutrophilia. The hematological effects were attributed to benzene contamination of the trimethyl benzene [ACGIH 1991].
Effects on Humans: Workers exposed to a solvent containing 80 percent trimethyl benzenes complained of nervousness, tension, anxiety, and asthmatic bronchitis; in addition, the peripheral blood showed a tendency to hypochromic anemia and prolonged coagubility of blood; the peripheral blood effects were attributed to benzene contamination of the solvent [ACGIH 1991].

* Signs and symptoms of exposure

Acute exposure: No signs or symptoms of acute exposure to trimethyl benzene have been reported in humans.
Chronic exposure: Chronic exposure to trimethyl benzene has caused nervousness, tension, anxiety, asthmatic bronchitis and blood changes in humans.