Tag Archive | finish

Lose The Sandpaper, Grab The Razor

Hold the razor almost vertical and then lean the top the direction that you push. After about 3 seconds you will get the feel.

Hold the razor almost vertical and then lean the top the direction that you push. After about 3 seconds you will get the feel.

One of the best finishing tips I’ve ever picked up came from an episode of “This Old House”. Norm and Tommy were building some cabinets for a house, and they were spraying a lot of plywood. They showed how they used a razor as a scraper to knock off the nubs between finish coats. It looked simple, so I gave it a go, and I haven’t looked back since.

Let me first start by saying that the razor isn’t perfect. It is flat and straight, so it doesn’t work for profiled edges or rustic, wavy surfaces, but it is great for big, open flat spots. I use it most often on sheets of plywood, but also use it on the flat spots of doors, including the stiles and rails.

The beauty of the razor is the simplicity and speed. With one razor blade, I can quickly smooth a surface between coats on a job that would eat up several sheets of sandpaper. The big difference is that the razor doesn’t clog up with finish like sandpaper does, it just scrapes off the high spots. This is especially helpful when I am trying to finish a job in just one day (which is usually the case). As long as the finish is set up enough to handle, I can start scraping with a razor and never have to stop. In the same scenario with sandpaper, it would clog almost immediately causing me to use more sandpaper and not get consistent results. The clogged sandpaper also tends to drop off little boogers of coagulated finish that stick to the surface. That never happens with a razor.

Using the razor is simple. Hold it up nearly vertical to the surface, lean the top into the cut and pull or push the direction you want to go. It works just like a cabinet scraper, only on a smaller scale, and it doesn’t need to be sharpened. When the razor is dull, just grab another one and move on. I often flip the blade around and cut the opposite direction to make the edge last even longer. If it feels like it isn’t cutting, flip it around. If it still isn’t cutting, just grab another one and get back to work.

Quick tips for using a razor:

  1. Make sure the finish is dry before scraping.
  2. Make sure runs are super dry before scraping. The finish should scrape off in shallow layers, not rub off in big chunks.
  3. Always use a new razor. Old razors can have nicks that scratch the finish.
  4. Use a razor on flat surfaces. Razors do not work on profiled edges.
  5. Watch the sharp corners. The corners of the razor can easily scratch the finish.
  6. Use a light pressure to start. Apply more pressure as you get more comfortable.

If you are going to be doing a lot of scraping, I highly recommend wearing gloves or putting tape on the top of the blade to serve as a handle. The blade gets hots and starts to dig into your hand during heavy use, so it is best to make it as comfortable as possible. There are plastic blade holders commonly available as well. They work fine, but they got lost easily. It seems like I can always find the blades (mostly because they came in a jumbo pack), but I can never find the holders.

As I mentioned, the razor is great for flat surfaces, even curved, flat surfaces (what?). Yep, that’s right, the ol’ curved flat surface, like the belly of an arch. The razor will work on a surface like this, as long as it can sit flat. You can still follow the curve by changing the angle of the blade and quickly scrape the surface.

The razor is not a good choice for profiled edges. First off, it often can’t reach where it is needed, and secondly, there is a great risk that one false move might destroy an edge. In this case, sandpaper or a Scotchbrite pad is the poison to pick.

I use the razor between coats of sanding sealer and even topcoats, when necessary. It makes for a speedy job and a quality one at that. The razor takes off only the highest finish, which is usually just dust nibs and other loosely clinging items (like the legs of flying insects). And, with a little extra pressure a razor will dig in deeper to help remove runs and other problems, like finger prints, smudges, etc.

When you use a razor for scraping a finish, watch the edges of the razor and your pressure. The edges of the razor are sharp and can easily leave an errant scratch. Use a light touch, so if you bump the edge into something it won’t plow a line through it. The lighter pressure also ensures that you don’t take off any more than the imperfections. Only apply more pressure after you get the hang of it and when you really need it.

Lastly, make sure to use only new razors. A razor that has even just one ding in it will scratch up the surface, and the scratches won’t show until the next coat is sprayed. Don’t be a cheap skate and try to stretch the blades you have. Buy a pack of 100 and rest easy knowing that you will use all of them, either for scraping or in a knife.

Using a razor on your newly applied finish will seem scary at first. Go slow, use light pressure and be careful. In just a few minutes you will get used to the feel of it. As you work, use your hand to feel the progress along the way, by rubbing the surface to feel for imperfections. Your hand will tell you what you’ve missed and where you need to work a little more. Give it a try, and after just one swipe of the razor, I think you will be hooked.

Fisheye In My Finish Again (and again, and again)!

I like to finish projects. It has taken me awhile to admit it, but I do. I am not scared away by sanding, and I can handle the torment of airborne dust and the occasional trespassing fly. It allows the artistic side of me to come out, and I appreciate how the finish can make my woodworking look better than I imagined.

At the same time, I am beginning to despise working on projects that are already finished, especially repairs, because they can’t come out better than I imagined. All that can happen is that new work doesn’t match the old work, or that I have to refinish the entire piece, or worse yet, I have to refinish the entire piece three times. “Three times?” you ask (maybe even out loud and with a wacky look on your face). Yep, three times. This is a whopper of a fish story – fish(eye) that is.

This is a close-up view of fisheye from a more recent project and sure to be the subject of a future posting (if not the next one).

Last year, I did a job that included taking an antique piece of furniture and making it work as a bathroom vanity. It was a very nice piece, purchased specifically for the space and didn’t require much woodworking. The only request from the customer was to shorten the depth of the upper drawers to allow for the plumbing and to spray the top with a waterproof finish suitable for a bathroom.

Easy enough, I thought. In this situation, I like to spray a product from M.L. Campbell, called Krystal, which is a two-part conversion varnish that is resistant to everything once the chemical reaction is done. And, it has a high solids-content, which means it builds to a thick film quickly. It also has the added benefit of working just like the lacquer that I normally spray and thins with lacquer thinner. The job was going to be especially easy because the piece of furniture didn’t need any repairs or touch-ups that required staining to match the existing color.

I wasn’t sure what the original finish was on the piece, so I did my due diligence and tested the new finish on an inconspicuous spot on the back of the piece. I wanted to make sure that my finish was compatible with the old and that nothing crazy was going to happen. I sprayed over the old finish and it laid down nicely and adhered great. No problemo.

I moved on to actual spraying and shot a coat on the top. It went on like butta’, shiny and smooth. I was going to be done in no time, but… then I looked closer, and I saw some spots, then some more and some more. It was like the oceans parting. The stuff I just sprayed that sticks to everything like glue was jumping off of the surface (not literally) and leaving areas of original finish surrounded by areas of new finish. I didn’t actually hear it, but I expected to hear the Snap, Crackle, and Pop of Rice Krispies. It was demoralizing and memorizing at the same time. I hadn’t ever run into anything like it, but then again, I mostly work on new wood, not old wood.

It was quickly obvious that there was something on the furniture that was repelling the new finish. The good news was that I didn’t need to worry anymore about wrecking the finish, it was already done. Lucky for me, the top could have used a little sanding and it was made of 1-1/4″ thick solid mahogany, so I didn’t need to worry about sanding through the veneer. I decided I was going to show this thing who was boss and jumped on it with my sander. In about an hour I had the whole top sanded to fresh wood, stained it with my favorite dye stains and was ready for a brand-new finish. In no time, I would build up three coats and be all done.

I sprayed the newly-stained, freshly-sanded top with my same favorite conversion varnish and it went on like butta’ again. Then guess what happened? The same thing. Not only the same thing, but the exact same thing. It was no less pronounced than the first time. Now, I was stumped. The first attempt was my fault. I should have cleaned the surface better or been more aggressive in my preparation. But on the second attempt I couldn’t have been more aggressive. There was nothing left but raw wood. I sanded past the old finish, past the old stain, and even deep enough that no original pores were left. It was new wood. Obviously, there was a problem with the finish.

The stuff I was spraying does have a shelf life, though I couldn’t tell you what it is. Also, I have to mix two parts together, so I could have done that part wrong. Or, maybe something else was in there that was throwing off the chemistry. I didn’t know, but I didn’t want to take any chances, so I left for the night to rest, regroup and resupply.

The next day I resupplied at Compi distributors (the best company I have ever worked with in any industry and worthy of their own blog posting) and got to talking about my issues. They have always been helpful and knowledgeable and suggested that the surface probably had wax on it. Duh!, I thought. Of course it had wax on it. I figured that part out. It was old, somebody waxed it, I was lazy, I did nothing about it, and now here I am. But, I did do something about it the second time. I sanded the whole thing down to raw wood. I can’t be any more proactive or retroactive or whatever you want to call it than that. But, James, the finishing expert at Compi, politely said to me that the wax was probably still there, down in the wood, where I couldn’t get to it – even with sanding. He said that he had seen this before and to treat it like wood with wax on it, and he also gave me a little dropper bottle of fisheye killer to add to my finish.

When I got to the job site that day, I first cleaned the top with naptha (which cuts wax) then with lacquer thinner (which may not have done anything, but made me feel better) and then added the fisheye killer to a fresh batch of my same favorite finish.

I sprayed the top and it went on like butta’ again. I stepped back and waited. Nothing. Nothing happened. My finish went on smooth and looked like any other finish I had ever sprayed. I am pretty sure that James was right and the wax was still there and it was cleaned up with the naptha. However, I did start with all new supplies, a clean gun and fisheye killer too, so I am not positive what fixed it, but it was fixed – finally. Now, whenever I work on an antique piece, I always treat it like it has wax on it and clean it with naptha first.

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