Varnishing difficulties.

[BAD ORCA]

Of course, all the info is important, but from my experience, it's about preparing the wood.
Any old varnish must be completely removed and the surfaced and sanded smooth, around 400 grit. Then a teak cleaner, I like "Snappy Teak-Nu Two Step Teak Cleaning Kit" best, but be careful, the stuff is dangerous. Wear safety glasses, gloves, and protect painted and metal surfaces from teak cleaner.
After cleaning the teak, the grain will have risen again, and it needs to be sanded to around 400 grit a couple of times, then repeating with 600 grit until it is very smooth. As above, use a tack cloth after every sanding. You do not want to varnish over sanding dust!
At this point I put a couple of coats of clear wood sealer on, thinned on the first coat. Sand to at least 600 after the clear wood sealer has dried. Now your wood is sealed from the elements, and you have something to varnish to.
Now is the time to thin the varnish (I prefer Pettit Z-Spar Captain's Varnish 1015) at least 50/50 or even more.
See above posts from here, just remember to sand between each coat, using a finer grit each coat after you are at the working strength. Sometimes full strength varnish just isn't possible, so don't feel any instructions on thinning are binding.
Below is varnish done aboard Skipping Stone at anchor. The before & after on a dorade and the helm seat, which was just too complicated to do well, in the time we had.

Thats beautiful. Thats what i want it to look like. I tried again this afternoon with a natural bristle brush and also tried a foam brush but got same results. I'm starting to wonder if its dust left over from my paper towels and that i need to use a tack cloth instead. I'm using blue shop towels to clean after sanding. The bubble/dusty particles (whatever they are) happen while brushing and no amount of tipping removes them. Maybe my surface is not as dust free as i think it is. Will go to home depot and grab some tack cloth tomorrow.

My poor little cockpit table is going to have a 1/4" thick layer of varnish by the time i figure this out.

 

[dlochner]

Thats beautiful. Thats what i want it to look like. I tried again this afternoon with a natural bristle brush and also tried a foam brush but got same results. I'm starting to wonder if its dust left over from my paper towels and that i need to use a tack cloth instead. I'm using blue shop towels to clean after sanding. The bubble/dusty particles (whatever they are) happen while brushing and no amount of tipping removes them. Maybe my surface is not as dust free as i think it is. Will go to home depot and grab some tack cloth tomorrow.

My poor little cockpit table is going to have a 1/4" thick layer of varnish by the time i figure this out.

Get a magnifying glass and take a close look. It is really easy to get bubbles into the varnish. Just this evening I was stirring some varnish and lo and behold, bubbles were forming. This project is a protect the wood project not a how beautiful it is project so I don't care a lot, but it was instructive.

 

[Joe]

I'm using blue shop towels to clean after sanding.

Jesus........!!!!!!!!!!!!! Shop towels???? Really'? Well, that solves a big part of the mystery. (And I was worried you were using old T shirts. ) I guarantee a tack cloth will make all the difference. It should have been mentioned in the application instructions. Follow the manufacturer's instructions, using the pointers you get here to enhance the process. By the way, besides varnishing, using a tack cloth with ALL wood treatment projects is recommended.

 

[jssailem]

Tack cloth... You can buy them or make them. They are a useful tool to improve the quality of your varnish work.

Traditionally, tack cloths are made from cheesecloth or a similar open-weave fabric that’s soaked in a sticky substance, which can vary from beeswax and oils to synthetic resins:​

• Beeswax: Natural wax that provides a gentle tack.​
• Oil-based: Various oils, such as tung oil or boiled linseed oil, diluted with mineral spirits, can be used to make a tack rag.​
• Synthetic resins: Modern tack cloths may use synthetic resins and plasticizers instead of oils or beeswax.​

That paragraph came from one of the word working sites I use. If you are using an oil based varnish, I have found a loose woven cloth (even gauze bandage material) dipped in mineral spirits and then wrung out can serve as a good tack cloth.
Reducing the contaminates will greatly improve the results. Vacuums with hepa filters, tack cloths, wind free space are all helpful. It is some times difficult to control everything, especially on a boat.

That is why there are often many repeats in a varnisher's life.

 

[BAD ORCA]

Jesus........!!!!!!!!!!!!! Shop towels???? Really'? Well, that solves a big part of the mystery. (And I was worried you were using old T shirts. ) I guarantee a tack cloth will make all the difference. It should have been mentioned in the application instructions. Follow the manufacturer's instructions, using the pointers you get here to enhance the process. By the way, besides varnishing, using a tack cloth with ALL wood treatment projects is recommended.

At least i used the right kind of alcohol

She is starting to look better. I sanded the surface heavily until it felt smooth to the touch instead of by eye. My next coat was much better. I think one of the previous layers had dust or bubbles that kept re-appearing with each new layer. The heavy sanding with #220 seemed to knock most of it back. I then cleaned much more thoroughly and recoated. 90% of my surface (debris?) seems to have gone away. I just think i need to be much more meticulous in my prep. To be fair though, I had no idea what i was doing and did barely no research. I thought it would be much easier than it turned out to be. I do like varnishing though, very satisfying to see the results. Compared to the Cetol that was on previously, its worlds better looking.

 

[jssailem]

There is also that great varnish smell as you lean up close to get a good look at the work, then inhale.

I wonder maybe that’s what caused the splitting headache the next day.

 

[Blitz]

Tack cloth... You can buy them or make them. They are a useful tool to improve the quality of your varnish work.

Traditionally, tack cloths are made from cheesecloth or a similar open-weave fabric that’s soaked in a sticky substance, which can vary from beeswax and oils to synthetic resins:​

• Beeswax: Natural wax that provides a gentle tack.​
• Oil-based: Various oils, such as tung oil or boiled linseed oil, diluted with mineral spirits, can be used to make a tack rag.​
• Synthetic resins: Modern tack cloths may use synthetic resins and plasticizers instead of oils or beeswax​

Do you ever worry that the Beeswax or Synthetic resins cause contamination to the surface? Wax i would assume would be not something you would want on the surface prior to varnishing.

 

[jssailem]

Good query, Neal. I have not experienced any problems. I am not rubbing the cloth on the surface. I am relying on the tack cloth to lift off any contaminates.

 

[dlochner]

Good query, Neal. I have not experienced any problems. I am not rubbing the cloth on the surface. I am relying on the tack cloth to lift off any contaminates.

I'm not sure I'm following the logic here. Beeswax makes the tack cloth sticky which allows it to pick up dust that it comes in contact with. OK, that makes sense. Can you explain how you would keep a beeswax tack cloth out of contact with dusty object and still pick up the dust on said object?

 

[LloydB]

Use the tack cloth like a feather duster over the surface to attract the dust off the surface rather than rubbing it off as you would when washing a window. And now I'm wondering if that would be a better option for my display or TV screen instead of the microfiber cloth I use.

 

[dlochner]

Use the tack cloth like a feather duster over the surface to attract the dust off the surface rather than rubbing it off as you would when washing a window. And now I'm wondering if that would be a better option for my display or TV screen instead of the microfiber cloth I use.

No. No matter how lightly the cloth is drug across the screen, some of the sticky stuff is going to come off onto the screen, which is bad. Stick with a clean microfiber cloth and maybe a little alcohol (not the drinking kind) to remove finger prints.

 

[dLj]

I've used resume free tape you can get from Mcmaster. I've actually looked at the surfaces after using this tape and it leaves no residue.

dj

 

[dlochner]

I've used resume free tape you can get from Mcmaster. I've actually looked at the surfaces after using this tape and it leaves no residue.

dj

Got a link to the tape?

 

[jssailem]

I'm wondering if that would be a better option for my display or TV screen instead of the microfiber cloth I use.

No

 

[dLj]

Got a link to the tape?

Friggin ' auto correct... The would be residue free tape.

There are several varieties - put in "residue free tape" into Macmasters search and several will come up. There are some really expensive ones but you don't need those - just get one of the cheaper versions.

I've done some pretty serious testing in my previous life - they do not leave a residue... If you still have problems finding it - let me know - when I'm on my computer I'll send you a link. I tried using my phone but can't seem to get it to work....

dj

 

[dlochner]

Friggin ' auto correct... The would be residue free tape.

There are several varieties - put in "residue free tape" into Macmasters search and several will come up. There are some really expensive ones but you don't need those - just get one of the cheaper versions.

I've done some pretty serious testing in my previous life - they do not leave a residue... If you still have problems finding it - let me know - when I'm on my computer I'll send you a link. I tried using my phone but can't seem to get it to work....

dj

Sometimes autocorrect helps. Thanks, I can find it on McMaster-Carr. I seem to spend a lot of time on that website.

 

[dLj]

Sometimes autocorrect helps. Thanks, I can find it on McMaster-Carr. I seem to spend a lot of time on that website.

Sometimes it helps - sometimes it's a real pain. Seems to depend on if it thinks it's really right and keeps correcting after I've already gone back and changed to the correct spelling.

McMaster-Carr is amazing. Although I wish they would get a bigger supply of metric sizes, they still have a pretty decent selection. I used to sit and peruse their catalog - something they don't publish anymore I believe - or maybe you have to have a purchasing account buying from them that is way beyond mine...

dj