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Today, I was having a conversation with one of my customers about spraying a conversion varnish (Krystal, from M.L. Campbell) and the problems he was having with getting it to lay down nicely after it was sprayed. He said that he applied is wet enough to blend together and not be rough, but that he had a lot of orange peel in the finish. After discussing the possible causes of the orange peel it became obvious that he needed to add lacquer thinner to the mix, which he did not do.
This customer is new to spraying conversion varnish, which is a two-part mix that sets up and hardens chemically like epoxy, forming a super durable finish. The information on the can talked about the 10:1 ratio of finish to catalyst, but apparently didn’t mention a thing about thinning with lacquer thinner, so he used none. Even if it was mentioned, I assume that he was worried enough about getting the ratio correct (click here to learn how to easily get the proper mixing ratios) and not messing up the mix that he never imagined he could, or even that he should add lacquer thinner.
In this case, my customer was getting orange peel because the finish was too thick for his two-stage turbine. The kids at the finish distributor led him to believe that he shouldn’t need to add thinner, but they did not ask about the power of his spray equipment, assuming that he probably had a turbine strong enough to finely atomize the finish without thinning.
I continued to discuss the need to add thinner with my customer, and pointed out that a non-thinned finish requires more turbine power than he currently has. If he owned a 4-stage or 5-stage turbine, he could probably use the finish without thinner, but not with just a 2-stage. I speak from experience on this one, because my everyday gun is an older 2-stage model, and it requires at least a bit of thinning on almost everything I spray. I am okay with this apparent shortcoming because I am a proponent of applying multiple thin coats, as compared to fewer thick coats, which I believe are just inviting trouble.
As our conversation continued, he asked the million dollar question, “How much lacquer thinner do you add?” For me, the simple answer is, “Until it sprays good,” which is very ambiguous I know, but true. I have an advantage because I have sprayed more than him and I have an idea where I am headed, but I don’t truly know until I shoot a sample board with it and see how things are flowing (which I do every time before I spray the real thing). I spray a sample piece of wood standing up vertically to make sure that I can get a fully wet and flat surface with no runs or sags and to get a feel for how fast I need to move the gun to make all of that happen. If the sample surface looks good, I move on and spray the real thing. If I have issues, it is usually because the finish is a bit thick, so I add lacquer thinner until the finish sprays smoothly without orange peel and without runs.
Another, more technical way to determine the correct amount of thinner is to use a viscosity cup. A viscosity cup is shaped like a funnel and determines how thick a fluid is by the time it takes to empty the cup. A thin fluid will empty in just a couple of seconds, while a thick fluid might take 30 seconds or more. When I started spraying and used a viscosity cup, about 15 seconds was the right amount for my gun, but it will vary from gun to gun. When learning to spray, I recommend using a viscosity cup and to follow the manufacturers recommendations. If nothing else, this will give you a good starting point from which you can make later changes and have a way to achieve consistent results. After you spray for a while, there will be less mystery, and you will know from one test shot what needs to be adjusted, even without the viscosity cup.
When my customer asked about adding lacquer thinner, I know he was worried about possibly adding too much, and after thinking about it, I don’t know that you can add too much. I can follow the logic that adding too much thinner may change the chemistry, but I mix the 10:1 ratio of conversion varnish to catalyst first and then add the thinner, so there should still be the same amount of resin and catalyst, just with more space between them, in the form of lacquer thinner which will quickly evaporate and let the two parts do their thing. Even with other lacquer products, which includes sealers, nitrocellulose lacquers and modified lacquers, I can’t think of any time that I have ever had a problem because I added too much thinner.
I’m sure finish manufacturers would disagree and warn you to not be so cavalier about it, but I sure wouldn’t worry about adding too much thinner. Simply add enough thinner until your spray gun is able to apply a nice, even and wet film that flows out flat and dries without sagging. Even if you do mix it a bit thin, feel confident knowing that you can always compensate by moving more quickly or reducing the amount of fluid coming out of the tip of the gun.
My sawmilling adventures began with an Alaskan chainsaw mill, which is just an attachment for a chainsaw to allow it to repeatedly cut a log lengthwise into lumber. It wasn’t anything fancy, and while it produced fine lumber, it was painfully slow to use. It didn’t take too many hours of me directly sucking in sawdust and fumes, while sweating my butt off, to start shopping for a more capable sawmill.
When I started my search, I considered bandsaws made by companies smaller than Wood-Mizer or TimberKing or Baker in a quest to also find smaller prices. While searching, I found several mills that looked suitable in the $5,000-$10,000 range, and I also came across a new “swing mill” from Australia called a Lucas mill.
The bandsaws looked to be a good choice as far as production went, but I didn’t have any way to move logs at the time, so the Lucas won out. It’s ability to easily break down and set up on site, while fitting in the bed of a pickup truck made it the clear choice, especially for larger logs. I say clear choice, but it wasn’t an easy choice. I didn’t like that the basic mill, fitted with a circular blade, was limited to 6″ or 8″ wide lumber without the optional slabbing bar attachment. And, my biggest fear was that this new mill from Australia, that I knew nothing about, might not be as good as it appeared in the videos.
Unfortunately, my fears were NOT immediately allayed. I went to pick up the more than $10,000 sawmill at the shipping terminal, and I couldn’t help but feel like I way overpaid for the amount of merchandise I picked up (Did I mentioned that it fits in the bed of my pickup truck?). There was only a sawhead, two long rails, and a few other miscellaneous metal parts that formed the frame ends. Besides that, the kit included a sharpener and some other odds and ends, but none of it added up to very much. I started doing the cost per piece arithmetic in my head, and it wasn’t looking good.
Regardless of my buyer’s remorse, I was tickled to have a “real” sawmill and set it up in my back yard the very first chance I got. After just a short time reviewing the directions, I had the sawmill set up and ready to cut. Even for someone who had never set one up, the Lucas went together fast. It was then that I realized what I had paid for. I didn’t pay for lots and lots of parts and extra bulk. I paid for an impressively designed machine, with an amazingly small stature, than can tackle the biggest logs. I paid for all of the research and design that went into the mill by the Lucas boys, and I paid to not lug around thousands of extra pounds, and I paid for everything to go together with minimal effort and a minimal number of steps. I got all of that and more.
From a design standpoint, I can confidently say that every part of the Lucas mill is well-planned and simplified beyond belief. The only mechanisms that I have ever had a problem with are the winches that raise and lower the ends of the long rails. They work perfectly fine and they are quite smooth, but they can be dangerous. When fully loaded with weight, it is possible to release the winch and lose control, resulting in a violently swinging handle that can smash your arm and allow the sawhead to come crashing down. I know from personal experience, as this has happened to me more than once, with the last instance leaving me at the hospital with a possible broken arm (luckily it was just a very bad contusion). If they were to ask, I would recommend that the winch system be built like the raising and lowering mechanism on my TimberKing 1220 manual mill, which magically is able to easily raise and lower the sawhead with complete control and without the possibility of having a disastrous crash. I have no idea how it works, but it smoothly operates the sawhead with a very heavy 15 hp electric motor attached to it like it isn’t there at all.
Now that you know to watch your arm and to be careful when lowering the sawhead on the Lucas mill, I can continue telling you how wonderful the Lucas mill is. First off, realize that I bought a Lucas mill in 1995, so I have been using one for about 2o years now, and I still use it on a regular basis. It is a very versatile machine that can handle big logs with ease. I often get asked how big of a log I can handle, and with the Lucas mill in my corner, I can just answer, “Yes.”
Currently, I use the 8″ model, which means that with the 21″ diameter circular blade attached it can produce up to 8″ x 8″ dimensional lumber. I rarely cut 8″ x 8″, but the mill can easily be adjusted to cut any dimensions under 8″. I often cut 1″ and 2″ thick lumber by 8″ wide.
The Lucas mill is called a “swing” mill because the blade can flip or swing with the pull of a lever from the horizontal to vertical position and right back again. The cool part is that both of the cuts line up with each other and work in concert to produce accurate and straight, completely edged lumber without a dedicated edger or any extra handling. In contrast, to edge lumber on a bandsaw mill requires flitches (lumber with bark edges) to be stood up in the mill and cut one or two more times to produce lumber with four square edges.
When cutting dimensional lumber I can easily work by myself making the vertical cut walking backward, then making the horizontal cut walking forward and finishing by sliding the cut board backward and out of the way. After a quick repositioning of the sawhead and a flip of the blade, I am back to cutting another piece of lumber. When cutting dimensional lumber like this I get in a rhythm–walk backward, flip blade, walk forward, slide board, move and flip blade, then repeat. The first cuts on the outside of the log are firewood, but after one pass across the top of the log and then dropping the mill to the next set of cuts, almost every pass produces an edged piece of lumber.
When I first got my Lucas mill I used it with the circular blade most of the time. Everything I produced was fully edged. Big slabs weren’t in style, so I didn’t even own a slabber, let alone use one. Now things are different. Live edges are in and so are big slabs, so the slabber is on the mill most of the time. The slabber is an attachment that turns the sawhead into a giant 2o hp chainsaw mill, with a maximum cut of 64″ wide.
I use the Lucas mill with the slabber attachment to cut all of my big logs that will produce slabs for table tops. With the slabber attachment the Lucas is not fast, but it can cut much wider than my bandsaw mill (maximum cut of 29″ wide), and it doesn’t make sporadic wavy cuts like the bandsaw mill. Knowing that I won’t get a miscut on a high-priced piece of wood gives me a great piece of mind.
These days when the slabbing attachment isn’t on the mill, the circular blade is, but not for milling lumber. I have been using it to flatten my kiln-dried slabs, and as long as the blade is sharp, it works great. After I move the slab into position, I just skim the surface with the mill to remove the high spots. Next, I flip the slab, drop the mill a bit and skim the other side. The end result is a perfectly flat slab, ready for final planing. The kids at Lucas sell planing and sanding attachments, but I haven’t used or purchased either one since I finish almost all of the slabs with the power hand planer or wide-belt sander.
Every time I use the Lucas mill, I am reminded how well it works, from quickly setting it up to making small adjustments, everything is simple. And, I know when I show customers how capable it is, they are impressed that such a lightweight, easy-to-setup mill can do so much.
Note: While Lucas is more than welcome to pay me to endorse their mills, as of now they do not. This was written for educational purposes and to let others know how my slabs are produced.