How do you calculate how much finish you going to need

Rob Keeble

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I have been doing some further reading on finishing since my recent attempts and use of waterbased finish.

One aspect that affected my finishing process and speed was quantity of finish.

Given i had decided to tint the finish i was using and not wanting to end up with a whole can of finish tinted to that shade i did what is recommended and dosed it out to a smaller glass container.

I used a syringe to ensure my tint was consistent in proportions but here is the catch.

Each time i thought i had mixed enough i had to mix a further batch. Then came the fact that i usually found this out near the end of whatever batch i was on.

Invariably this meant i had to mix another batch and i did this in a second container to ensure if something went wrong the previous left overs were not contaminated. When i saw i had it right i blended the two mixes so as to form a single batch.

But i went through this process so many times. It slowed me down significantly.

Part of the cause was me being frugal as all get go. Dont ask why i dunno.

But the biggest issue was having zero clue as to how much to mix in the first place and how to calculate how much to mix.

I am pretty sure i am not the only one that has encountered this issue so has anyone any words of wisdom to offer.

I can understand a factor of percentage x for say overspray if one is spraying but whether spraying or painting or wiping where does one start in the first place.

Its all good and well to say experience but I did not keep track of how many batches i mixed previously and i know for a fact i wasted a fair bit in the contstant wash up of various implements used.

In fact i reckon i would have made my life one heck of a lot easier had i simply tinted the entire can and be done with it and if it had left over so be it. Label it call it something and store it until it comes time to throw it out.

But this finish is not cheap stuff so it got me going.

I dont know why we do this to ourselves but i simply hate waste of anything.

Thoughts tips and advice would be appreciated. Thanks:thumb:

Oh and i even dont mind any jokes you can make about me or my process i like a good laugh. :D
 
rob experience is the best teacher,, how much finish does it take to do a vanity dresser? i bet you can get real close now.. use that as a quide for the next time. the can coverage numbers are just an approximate..
 
Rob, I run into the same situation when I'm spraying turned pieces, just in smaller increments. When I'm spraying dyes I tend to mix one or two fluid ounces at a time, but there have been times when that wasn't quite enough, so I'd mix a bit more. Then a bit more. Then a bit more...
 
Like Vaughn, I mix dyes in small batches, keeping track of the amount of dye I'm adding. I like to tone a piece using dye mixed in DA and, in some cases, airbrush in on with a small sprayer. After getting the appearance I want in that manner, I spray clear topcoat of whatever product I've chosen.
 
When I am just using a toner, I don't worry about the the quantity of a single dye, since the technique I use is to spray multiple light coats until I get the intensity I want on the piece. That also helps hide sapwood since I can spray a little heavier in parts of the piece. If I mix more part way through the job, I may make the later batches a little less intense since I am covering spray imperfections as well, and the "thinner" color allows easier fixing. Then final coats are clear finish.

If you are essentially "painting" so the finish isn't transparent this doesn't apply. If I have to mix the toner from multiple color sources, this doesn't apply unless you want to shift the color in the later coats.
 
I keep stupidly specific details on a finish formula. I have cheap little measuring spoons, cups, graduated cups and so forth on a loop of cord. Re-mixing 2 ounces or a quart is not an issue for me. Needing 2 ounces at the end of a finishing job is an issue for me. :p

As mentioned, experience is a good (if sometimes expensive) teacher. I tend to make (assuredly) more than I need. I am more comfortable using the waste on shop fixtures or to kill ants (just kidding) than I am stressing during a finishing session. ;) So, how much is the right amount? . . . Plenty more than I'll need.
 
Thank yu all for your replies.


:doh:There are times i could kick my own butt. Seems way to often lately.

Thanks Chalie you just set off a spark in my head that should have been obvious to me.:eek:

Glenn thank you too. I have bought my wife so many sets of measuring scoops of all kinds and yet never stopped to think of getting my own set. :doh::eek:

Couple of those would have made life so much easier that the syringe i was using. Sometimes we just get fixated on something and dont see the wood for the trees.

I agree its way better in future to have more ready mixed than to be messing around when i am in the throws of finishing.


Do any of you like in your case Charlie, keep jars of premixed tone for say things like toning maple. Sort of like your formula that when "that" wood comes up its your go to jar.?
 
Rob, if I mix a batch of dye in a single color (red, blue, black, etc.) and have leftovers, I'll put it in a small jar or container and use it as a starting point for a later batch. (I'll sometimes also do this with mixed colors, but usually not.) With the dyes I use, even if it dries out, I can re-use it by adding alcohol or water. Of course, the color intensity from batch to batch varies using this method, but so far I've never been in a position to need to match a color I'd previously applied. I have mixed batches of dye to match an existing tinted finish, but that was a one-time mix of multiple colors, so it probably wouldn't have been a suitable 'starting point' for a new piece at a later date.

Here again, this applies to turned pieces. If I was doing furniture, I suspect I'd be doing something similar, just in larger quantities.
 
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Do any of you like in your case Charlie, keep jars of premixed tone for say things like toning maple. Sort of like your formula that when "that" wood comes up its your go to jar.?

Anything that goes in the gun never goes back into the original inventory (kept in plastic 2 quart juice containers), so there is no question of virgin finish coming out of the container. I have a collection of old jam jars with, typically, 4 ounces of each finish dumped out of the gun, that I use to start the next run of that finish ... jars of waterbase lacquer, gloss water base conversion varnish, satin water base conversion varnish, sealer, etc. etc. When I use a common dye in a finish (always in the gloss lacquer), I keep that jelly jar of leftover, too, but if I mix a custom dye (rarely) it gets dumped.

Right now I am refinishing an oak table that had a walnut stain. Only the top needed refinishing, so I need to match (at least roughly) the legs and apron. My TransTint Medium Brown dye, #6004, has a slight orange tint, and is great for hiding sapwood in walnut. However it was way too red for the oak table. The TransTint Mission Brown, #6006, is a very plain brown, not that good on walnut, but very close to what I needed on the oak tabletop. I sprayed several coats of mission brown, gradually building the color intensity. I saw that I needed to "warm it up a bit" so I sprayed a regular coat of Medium brown (with the hint of orange) and was almost there. One more very light coat of medium brown last night, and I think I am done - I spray outdoors, so will see what the full bright daylight says in an hour or so. If I am happy with the color, I will switch to clear finish today, and be done with the table before the day is over.

This long story leads to a jam jar of Medium brown in WB lacquer - whatever was leftover from the gun, and a separate jam jar of Mission brown in WB lacquer, again whatever was leftover from the gun. The concentration of each isn't that important, since I control the concentration with my spray technique... if it is dark, spray a thinner coat, if it is too light, I either add dye or do an extra coat or two. But I am not worried about the amount of finish that I have to mix in a color since I control the color intensity while I am spraying.

Is this the best way? I doubt it, but it works for me.
 
Thank you Charlie for your detailed response. I get it. I can now see the merits of accumulated experience in finishing.
I have come to the conclusion i need to worry and analyze less and get on with the doing and the obvious will inevitably happen.
Until i tried the mixing of stain with the finish as Rich suggested for the maple on the vanity, I had always been rather myopic about stain and color. I guess this comes from being led by the nose by the fixed range offerings at the store.
Slowly i am loosening up:)
Its quiet another adventure.
I trully appreciate the input and feedback.

Sent from my MB860 using Tapatalk
 
Rob keep Green stain on hand and blue stain on hand also. Depending on the direction the red goes is either mahogany , walnut, cherry these 2 colors will warm up or cool down the brown.
 
Yep, now that's what I like someone who doesn't 2nd guess me and thinks on their feet.
Green will all a nice worm look to red where the Blue will cool it down.

I use Green mostly in Walnut , mahogany, cherry, Oak, hickory and maple sometimes. What this doe is to give a little older look to the piece.

Blue in Mahogany will give and aged mahogany look.
Green for cherry, hickory and oak
Blue or green for walnut and maple
 
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