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Bill Jobe
01-05-2018, 3:55 PM
I still have not finished this piece first turned about a year ago. It has several coats of tungue oil finish, but after the last coat, when I sanded it again for another finish I created a lot of scratches that I have spent hours trying to remove, but the finish just clogs sandpaper and I put it on the shelf for now.

So now I have a piece that I suppose I either have to settle for visible scratches or conpletely remove the finish.
Another way has come to mind that i'd like opinions on.
I found orbital disks up to 2000 grit.
Do you think using it in my orbital sander i could create a reasonably nice finish after stripping it?
I love hand sanding, but this piece is hard to sand well enough by hand to satisfy me.
Any thoughts?

John K Jordan
01-05-2018, 4:56 PM
Hard to tell from the photo - is that a shallow platter? A random orbital sander does well.

I use two pneumatic ROSs, one with 1" or 2" disks and the other with 3" disks. Here is the 3" in use:

375547

That said, I usually remove problem scratches by hand with wet sanding. If finishing with oil, I'll wet sand with the same oil. (I haven't used tung oil but should be similar to the "danish" oil I use) If the scratches are in the finish, I'd certainly try the wet sanding before removing the finish. Sanding with oil should prevent the paper from clogging. I'd start with the same grit that made the scratches or one grit coarser.

I never us a rotating sanding disk on an electric drill. My normal method of work for pieces like that is turn, use hand scrapers to remove all tool marks, use ROS starting with whatever grit it takes (sometimes 600, sometimes maybe 320), sand and/or wet sand by hand with oil to remove any problem scratches working with the grain if possible, then wet sand with finer paper, then 0000 steel wool or pumice/rottenstone, then oil finish.

Most of my sanding is by hand with paper backed up by a soft sanding block, a white rubber eraser:

375557

JKJ




I still have not finished this piece first turned about a year ago. It has several coats of tungue oil finish, but after the last coat, when I sanded it again for another finish I created a lot of scratches that I have spent hours trying to remove, but the finish just clogs sandpaper and I put it on the shelf for now.

So now I have a piece that I suppose I either have to settle for visible scratches or conpletely remove the finish.
Another way has come to mind that i'd like opinions on.
I found orbital disks up to 2000 grit.
Do you think using it in my orbital sander i could create a reasonably nice finish after stripping it?
I love hand sanding, but this piece is hard to sand well enough by hand to satisfy me.
Any thoughts?

robert baccus
01-05-2018, 9:35 PM
Wet sanding with tung oil may work well. Also wet sanding with soapy water has worked for me as well.

Bill Jobe
01-05-2018, 11:20 PM
Hard to tell from the photo - is that a shallow platter? A random orbital sander does well.
JKJ

You've seen it before, John. It's here:

http://www.sawmillcreek.org/showthread.php?254772-Wet-sanding-on-the-lathe

I had it almost perfect with hardly a trace of scratches, then after another coat of tung oil finish I somehow managed to scratch it in several places. Did not see them until buffing thar next coat.
For some reason this piece is very difficult (for me) to hand sand and not leave scratches. Wish I'd quit while I was ahead.

Robert, do you always use a wax finish after soap and water? If not, how do you get all of the soap out of the wood for an oil based finish?

John K Jordan
01-06-2018, 8:42 AM
You've seen it before, John. It's here:
http://www.sawmillcreek.org/showthread.php?254772-Wet-sanding-on-the-lathe
I had it almost perfect with hardly a trace of scratches, then after another coat of tung oil finish I somehow managed to scratch it in several places. Did not see them until buffing thar next coat.
For some reason this piece is very difficult (for me) to hand sand and not leave scratches. Wish I'd quit while I was ahead.


Yes, I remember now. It looked like a big flat disk. Are the scratches across the grain? A lot of scratches? Deep into the wood?

It's hard to guess what to recommend without knowing seeing the piece or at least knowing how you work, exactly what you did in this case (the grit used, just how you sanded by hand), and the extent and type of scratches. I can't guess why you are having trouble with hand sanding. Maybe a sanding session with an experienced local turner would be helpful.

I can't see where you said the kind of wood - is is a hard or soft wood? For softer wood and wood with open grain I generally start with a coat of shellac or lacquer sander sealer on the bare wood, usually thinned so it soaks more into the surface. Depending on the wood I would let it dry then repeat. This helps in later steps.
For a repair you can always sand back to the wood with coarse grit and start over. (unless there is fine detail that would be wiped out with the coarse paper) A firm backing pad of some sort is important for wood with softer and harder places to keep from wearing away the softer sections for an uneven surface. I almost always use slightly curved hand scrapers instead of coarse sandpaper which keeps the surface even.
375603
I grind new curves on rectangular scrapers as needed. These greatly reduce the amount of sanding needed - as mentioned before after such scraping I can sometimes start and end with 600 grit then finish. Not seeing your piece or learning more about it, if you don't want to acquire and learn to use the scrapers (and if the localized wet sanding didn't satisfy you) it might be best to take the piece back to the bare wood and start over. I might try using either the ROS you mentioned OR hand sand with a firm but flexible sanding pad, perhaps something like a foam pad (e.g. wet suit material) glued to a block of wood, the wood perhaps domed very slightly. I almost always hand sand with the grain, although I sometimes sand across the previous sanding scratches with the same paper. This will show any deep scratches since you should easily be able to remove any scratches made with the same grit.

Cleanliness is extremely important - one stray particle of coarse grit can force you to go back to earlier grits. (If it is an open grain wood like walnut a coarse particle of grit can hide inside a pore and come out to ruin the work. A good way to prevent this is fill the pores first. A grain filler will work as will wet sanding with oil.) After sanding with each grit I generally blow off the dust with the air compressor then wipe the surface with a clean piece of paper towel soaked with naptha. This will clean off the dust and grit AND reveal any rogue scratches. As the naptha begins to dry in one area I tilt and turn the surface in various angles and directions under a bright, glancing light from a small task light source (not a diffuse light such as from long overhead fluorescent blubs). This will reveal scratches that may otherwise be invisible. Sorry if all this seems rambling and incomprehensible - I've been up half the night and took a strong pain killer for a kidney stone. Not exactly good fun.

I don't understand why you mentioned the 2000 grit orbital sanding disks in the first message. I hope you're not trying to use fine paper to remove coarse scratches.
JKJ

Bill Jobe
01-06-2018, 5:30 PM
Very sorry to hear about your kidney stone, John.
I know a guy who years ago had one pass as he was standing at a wall urinal and he said the instant pain was so intense that he doubled over so hard that he broke some teath on the plumbing.
Hope yours goes better from hear on.

The piece is from a 4" slab of kiln dried walnut. I can't begin to tell you how long and hard I worked getting it just the way I wanted it, then having to start over. It has a cavity as you can see, and I used compressed air to clean the surface of particals. Then I wiped it down with either alcohol or mineral spirits, I can't remember which. I had put a few coats of tung oil finish without problems. It sat for quite some time as I had moved on to another piece, so it was fully cured.
I picked it up again and after lightly sanding with 320 I noticed the scratches when I applied another coat of the same.
So I started wet sanding with 220 then 320 .
By then I had scratches all over, so I went to Han sanding again very carefully following the grain as best I could.
Seemed all my efforts were in vain so I set it aside again until now.
I thought starting with maybe 220 and working up I could remove the scratches using the orbital sander.
Just looking for suggestions as to how best to go about it. As it is sandpaper just loads up with finish.

robert baccus
01-06-2018, 10:34 PM
Sorry about the scratches. The soap is no sweat as you only need a teaspoon of kitchen soap(something I as very familiar with) per gallon of water--it is only to break the surface tension of the water and will leave no traces on your piece. All car paint jobs are presanded this way using plenty of water/soap--also is a lubricant. Hard, oily tropicals (including Bo-Darc, mesquite, pine hearts ect) can be sanded this way as they are practically waterproof. Dry a bit and finish as usual. Also when sanding finishes toss the sandpaper and go to 3M sanding sponges in fine grits--they simply scratch much less.

Leo Van Der Loo
01-07-2018, 12:30 PM
I still have not finished this piece first turned about a year ago. It has several coats of tongue oil finish, but after the last coat, when I sanded it again for another finish I created a lot of scratches that I have spent hours trying to remove, but the finish just clogs sandpaper and I put it on the shelf for now.

So now I have a piece that I suppose I either have to settle for visible scratches or conpletely remove the finish.
Another way has come to mind that i'd like opinions on.
I found orbital disks up to 2000 grit.
Do you think using it in my orbital sander i could create a reasonably nice finish after stripping it?
I love hand sanding, but this piece is hard to sand well enough by hand to satisfy me.
Any thoughts?

Bill your biggest problem is the stuff you use, as you call it Tongue oil finish :eek:, that stuff is just thinners and volatiles and no Tung oil at all, it will not build up a finish like the Tung Oil.

I have used Tung oil for many years already, and normally use the Polymerized Tung Oil, as it hardens faster and gives a higher gloss than the Tung Oil that is not treated.

I wipe from 2 to 4 coats of PTO (Polymerized Tung Oil) on my turnings, depending the wood and gloss I want to get, Black Walnut gets often 3 or 4 coats for the open grain it has.

The way I do this is, wipe on a liberal coat of PTO, wait 10 minutes and than wipe the piece down, removing all I can, let the piece sit for a day in a warm dry place, then add another coat, same as before.

One thing with open grain like Black Walnut, I will rewire the piece again in 20 minutes or so, as the oil will sometimes bleed out of the grain, and show up later as tiny bubbles.

After enough coats (2, 3 or 4) I set the piece away for a month or maybe longer IF I want to polish the finish, the PTO finish should be nice and hard by then and polish up well.

Here are a couple pictures, first one is from some smaller bowls from different woods,like Apple, Hickory, Aspen, Osage, Ailanthus, Black Cherry, Black Walnut, Elm and Maple, the other pictures are from Black Walnut.

As for sanding your piece now, I would hand sand with the grain till the scratches are gone and then add the PTO.
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Bill Jobe
01-08-2018, 1:10 AM
Bill your biggest problem is the stuff you use, as you call it Tongue oil finish :eek:, that stuff is just thinners and volatiles and no Tung oil at all, it will not build up a finish like the Tung Oil.

I have used Tung oil for many years already, and normally use the Polymerized Tung Oil, as it hardens faster and gives a higher gloss than the Tung Oil that is not treated.

I wipe from 2 to 4 coats of PTO (Polymerized Tung Oil) on my turnings, depending the wood and gloss I want to get, Black Walnut gets often 3 or 4 coats for the open grain it has.

The way I do this is, wipe on a liberal coat of PTO, wait 10 minutes and than wipe the piece down, removing all I can, let the piece sit for a day in a warm dry place, then add another coat, same as before.

One thing with open grain like Black Walnut, I will rewire the piece again in 20 minutes or so, as the oil will sometimes bleed out of the grain, and show up later as tiny bubbles.

After enough coats (2, 3 or 4) I set the piece away for a month or maybe longer IF I want to polish the finish, the PTO finish should be nice and hard by then and polish up well.

Here are a couple pictures, first one is from some smaller bowls from different woods,like Apple, Hickory, Aspen, Osage, Ailanthus, Black Cherry, Black Walnut, Elm and Maple, the other pictures are from Black Walnut.

As for sanding your piece now, I would hand sand with the grain till the scratches are gone and then add the PTO.
375707 375708 375709 375710


Sir, I have faith in whatever word you right.
I will give that product a try.

By the way, the Yew root ball you strongly suggested drying as fast as I can. It is now below 10 everywhere. I lightly sanded away the surface including the white areas and I think it is going to be a very pretty piece of wood once I get it done.
Would you think PTO would be a wise choice for it?
I'll post a pic on that thread.

Leo Van Der Loo
01-08-2018, 9:36 PM
Bill Polymerized Tung Oil is a good finish for any wood, and will give a good protective finish.

Hope you will show that piece when done :)

John K Jordan
01-08-2018, 11:45 PM
Bill Polymerized Tung Oil is a good finish for any wood, and will give a good protective finish.


Do you have experience with various brands and a preferred brand? Sometimes the labels don't give full information.

Hope's, Formbys, Old Masters, are these polymerized?

Leo Van Der Loo
01-09-2018, 3:58 PM
Do you have experience with various brands and a preferred brand? Sometimes the labels don't give full information.

Hope's, Formbys, Old Masters, are these polymerized?

John, I think you know where to find the MSDS sheets if you don’t believe what’s on the container is correct.

Of course one can always call their finishing product “Danish Oil” as that can be any concoction, as there is no such thing as Danish Oil, just what people think or hope it is, thinners, BLO and heavy metals varnish and whatever else one can think about adding.

With the so called “Tung Oil Finish”, if you find something like this in the MSDS sheet 375898 (accent added by me), you know that there is no polymerizing oil in this mixture of volatiles, or else there could be a hazerdous condition with the oil when polymerizing.

What one does get is a couple of health hazards in the form of 65% mineral spirits and cobalt 2 ethylhexanoate and then some other chemicals

I personally use the Polymerized Tung Oil that Lee Valley sells, I do know what it gives me as a result when using it.

John K Jordan
01-09-2018, 8:32 PM
I think you know where to find the MSDS sheets...
I personally use the Polymerized Tung Oil that Lee Valley sells...

Yes, I can and did look up the MSDS on various tung oil products. Do you know where the MSDS on the Lee Valley product can be found? I guess I was really looking for an endorsement from someone who has tested and compared different products so I don't have to test them myself. The experts all seem to say study the product labels carefully, not practical with some products without buying them first. One problem I found with the various MSDS that none I checked use the word "tung" anywhere except in the name, perhaps since tung oil in itself is not a safety hazard. Another problem is I could not find an MSDS sheet on the Huile D'abrasin tung oil that Lee Valley sells, either the polymerized or non-polymerized.

The tung oil that Lee Valley sells states it is heated to encourage polymerization (dries/cures faster). However, it does contain 50% mineral spirits for thinning. They also sell pure tung oil, non-diluted, and recommended diluting it yourself before use as needed. It's significantly cheaper than the diluted, polymerized product, $30 vs $50 per liter.

I've been leery of products that claim on the label to contain tung oil when they didn't explicitly state "polymerized" since I've read that raw tung oil can be very slow to dry. However, Real Milk Paint's "Pure Tung Oil" does not claim to be polymerized but indicates it is "naturally polymerizing". Hope's indicates it is 100% raw tung oil and will polymerize, but slowly.

Formby's and Minwax tung oil finish along with a bunch of others, as we all should know, contains no or very small amount of tung oil.
https://www.popularwoodworking.com/techniques/finishing/oil-finishes-their-history-and-use

All the uncertainty and hard to find truth about tung oil has encouraged me to stick with am oil/varnish blend such as Watco "danish" oil which works well. Perhaps I'll try the Sutherland Welles or the Huile D'abrasin oil Lee Valley sells. I may look first in Flexnor's or other finishing books and check what Russ Fairfield says.

JKJ

Leo Van Der Loo
01-09-2018, 10:46 PM
Why would you start using the French name Huile D’abrasin, it is the french name for Tung oil, they do have all the finishing oils names in English.

Any MSDS sheet that is covering a finish that has Tung Oil or Boiled linseed oil in it will have to include the hazard that is present with the polymerizing oil when using rags etc, if there is no polymerizing hazard , there is no polymerizing oil in there like Tung Oil or BLO.

It is why I added the part from a MSDS sheet that shows there is no hazard of polymerization, as it spell this out like this, “Hazardous Polymerization - Will not occur” and Carbon Dioxide and Carbon Monoxide will be produced by fire.

The Polymerized Tung Oil that Lee Valley sells has mineral spirits added because the oil becomes too thick to use easily after it has been heated, so that is the reason for the addition of the mineral spirits.

You seem to pick and choose what you like to believe, Pure Tung oil takes not as long to polymerize as BLO or your “Danish” Oil, it does take longer than Polymerized Tung Oil, as that will harden in about 8 HRS in the right conditions, and Pure Tung oil maybe a full day.

And yes Tung oil will start polymerizing right away, it does react with the oxygen in the air, the reason to keep air away from Tung Oil if you want to keep it for longer, the reaction that has happened can not be reversed.

For those that like a paint like or plastic looking finish, the BLO Varnish mix is pretty good and low cost, “Danish” Oil will fit the bill I do believe, have fun.

John K Jordan
01-09-2018, 11:35 PM
Why would you start using the French name Huile D’abrasin, it is the french name for Tung oil, they do have all the finishing oils names in English.


Oh, that's funny! I just got the name off the can in the Lee Valley ad and thought it was a brand name! Maybe I'll call Lee Valley and see who makes the tung oil finishes they sell.

I'll have to finish reading your message in a couple of days. (Surgery in the morning) Thanks for your time.

Bill Jobe
01-10-2018, 12:17 PM
I wish you the very best with the surgery, John.
You didn't mention what it's for but I'll keep you in mind tomorrow.

Hey! I had forgotten that I'm the OP.
I wouldn't mind off topic input if you care to share. If not, that's ok, too. Get well soon.

Bill

Bill Jobe
01-10-2018, 12:32 PM
I want to thank all of you for your suggestions and advice.

Leo, are you saying that the tung oil you use is not just a wiping varnish like Formby's. From what I've been able to gather Fornby's and Minwax are just wiping varnish that contains heavy metals to speed drying .
How does PTO differ? From what you've written it sounds like something I'd like to try
Wood finishing is confusing enough without all the misleading advertising. Minwax ought to be ashamed.

robert baccus
01-10-2018, 7:25 PM
Last time I looked Formby's had no tung oil in it!!

Leo Van Der Loo
01-10-2018, 9:37 PM
I want to thank all of you for your suggestions and advice.

Leo, are you saying that the tung oil you use is not just a wiping varnish like Formby's. From what I've been able to gather Fornby's and Minwax are just wiping varnish that contains heavy metals to speed drying .
How does PTO differ? From what you've written it sounds like something I'd like to try
Wood finishing is confusing enough without all the misleading advertising. Minwax ought to be ashamed.

You can get all the info here, the Polymerized Tung Oil is pure Tung oil that has been heated (gets thick through that treatment) and then mineral spirits added to thin it enough to be able to wipe onto the wood.

http://www.leevalley.com/us/Wood/page.aspx?p=20050&cat=1,190,42942

Leo Van Der Loo
01-11-2018, 10:38 PM
One more thing, I buy the 1 liter cans, and distribute the oil into 2 re-closable beer bottles, every time I use some of the PTO (Polymerized Tung Oil) I will add water to the bottle to get the oil right to the top and so eliminate the air contact with the PTO, the cloth that I use to spread the PTO on the bowl, is either burned right away or if a small one, spread out onto the concrete floor to make it safe.

Two pictures here, first the closure on the Beer bottle, and the second picture showing the water in the lower part of the bottle with the PTO on top of the water, I have kept the PTO imperfect state for a couple of years this way.

376105 376106

Bill Jobe
01-12-2018, 6:24 PM
Thank you for the information, Leo.
This form of tung oil would be food safe much sooner, i'm guessing?

robert baccus
01-12-2018, 10:18 PM
Last time I looked Formby,s tung oil finish had zero tung oil in it???

Bill Jobe
01-13-2018, 3:06 AM
Last time I looked Formby,s tung oil finish had zero tung oil in it???

I'm equally frustrated with Minwax for its false claims,Robert.
How do they get away with it. If one company can make such claims that do not reflect reallity, we have to assume that all companies are getting away with "fake news", even those who provide our food.
Tunge oil finish is a hazardous product. They should be held responsible to the public regarding its contents.

Leo Van Der Loo
01-16-2018, 2:20 PM
I'm equally frustrated with Minwax for its false claims,Robert.
How do they get away with it. If one company can make such claims that do not reflect reallity, we have to assume that all companies are getting away with "fake news", even those who provide our food.
Tunge oil finish is a hazardous product. They should be held responsible to the public regarding its contents.

Yes Bill, that’s why they use the word FINISH behind there OIL, as they say this FINISH will make it look like a real (whatever oil) finish you get when using it, and of course who do you believe.

Go and look at the MSDS sheets to find what’s in it, likely 70% or more volatiles and then varnish maybe or something else, not oils that polymerize and harden up, would be to costly and everyone likes low prices, even when the product doesn’t deliver the promised finish.

Bill Jobe
01-16-2018, 6:41 PM
I sanded the piece with 220, then 320 using soap and water and an orbital sander. The scratches were gone. I must conclude that the scratches were just in the finish and not the wood.
After letting it fully dry I applied Minwax Wipeon Poly using it to wet sand with 320 grit.
After 10 or 15 minutes I wiped it dry. The next day I wet sanded very lightly with 600 grit and the poly. I wiped it dry and today I used an orbital buffer to polish it. The color is deeper and flawlessly smooth with no scratches.
I use only high gloss because I read that you can create any level of shine by how you buff it.
My finish is low in luster, but really brings out the figuring on this piece of walnut.
Would you recommend a wax for a greater shine or another wet-sanded coat followed by a buffing or polishing compound?