People who tackle the very labor intensive task of stripping surface finishes from cabinets and furniture know they are going to save major money when comparing there sweat equity to the cost of having a professional refinisher do this work.
Basic requirements for the task at hand are: Ample elbow grease for the scrapping and scrubbing of the old finish off the surfaces to be stripped. A tolerance to strong solvent vapors associated with methylene chloride wood strippers and lacquer thinner. We will go over a longer list of tools and materials after you understand a few safety requirements.
For this discussion we are talking about professional industrial stripping materials and techniques. Methylene chloride is the strongest and quickest chemical that dissolves surface finishes. This chemical is a known carcinogen. Limiting exposure to all the chemicals discussed herein is very important. There are safer bio chemical strippers available however none perform with the speed and effectiveness of methylene chloride strippers. The following list of safety equipment is vital to limiting exposure to these chemicals.
1.Gloves– 8 mm. nitrile rubber gloves hold up to the chemicals the longest and still allow the dexterity needed to handle the putty knives, scrubbers and stripper brushes used. Buy a box of 100. You will need to change them often as they fail due to chemical exposure.
2.Safety glasses or goggles. Buy them and wear them. It’s no fun if you should accidentally flick a little chunk of stripper in your eye. There are eye flush kits available and are handy if this should occur. Other wise head for the kitchen sink, garden hose or shower to flush out immediately.
3.Proper clothing. Throw away paper overalls do the job well. Old jeans and long sleeve shirts work well also. The important thing is to have your arms covered above your gloves as you may flick stripper and or lacquer thinner onto your arms.
4.Respirator. You do not want to inhale methylene chloride and lacquer thinner vapors. Respirators are also very effective in keeping out wood dust when you start sanding your stripped surfaces. I use and recommend the Survivair brand half mask respirator.
5.Fans. Too ventilate enclosed work areas. Cheap box or stand fans are sufficient.
6.CO2 fire extinguisher. One in the vicinity at least.
Preparing the Work and Work Area for Stripping
Before you even think about breaking out the stripper and lacquer thinner you need to prepare your work area for safe stripping. These are flammable stripping materials. A well ventilated work area is mandatory. Stripping materials will evaporate rapidly when exposed to direct sunlight increasing materials cost. A covered work space is the best. Outside on a covered patio or driveway is great. A garage is ok too, but be sure to extinguish / turn off all open flame / spark sources, i.e. water heater, gas or electric furnaces, gas or electric clothes dryers, refrigerators etc. These ignition sources must remain off for the duration of the stripping process. They may be turned back on at the end of the work day as long as all strong flammable vapors have diminished.
Additional safety note re: refrigerators or other heavy appliances / machinery. It is imperative that refrigerators and anything with an electric motor that may automatically start in the working area be turned off during the stripping process. Many hobbyist wood finishers and even some professionals who should know better are unaware of the fact that when a refrigerator motor cycles on, it can cause a spark that under the right circumstances can cause a fire igniting the strippers / lacquer thinner vapors. Removal of the refrigerator completely out of the kitchen into another room is not only safer but allows use / access of the refrigerator during stripping and refinishing.
Turning off the circuit breakers in a room you are working in is a good idea especially if you are stripping wall paneling or cabinet faces that may have electrical outlets in them. Fluid solvents penetrating into any confined space where there may be exposed electrical wires could potentially cause a short circuit resulting in a fire. In addition scrapping flammable stripper off these surfaces with metal putty knives and or scrapers can cause a spark when they strike metal in just the right manner, i.e. electrical outlet boxes, exposed nail heads, screws etc.
Finally always have at least one heavy duty CO2 fire extinguisher handy, close to the exit / entry to the area in case fire does occur. Following all these afore mentioned safety precautions will prevent this worst case scenario.
Surrounding surfaces in the work area need to be protected. Covering wood patio decks, interior floors even garage floors to prevent damage to these surfaces is important and is the first order of business.
Carpet in a room to be stripped is best removed. The cost of a carpet layer removing and replacing carpet during the stripping / refinishing process is cheap compared to the cost of replacement if damaged.
I recommend three layers of protection for wood and vinyl floors that are not to be refinished / replaced. Stone, tile or cement surfaces may not need this level of protection other than grout lines that may absorb stripping and or finishing materials.
The first layer of protection is 1 to 2 mil plastic. You can buy this in rolls at all paint / hardware stores. It comes in rolls up to twelve feet wide and four hundred feet long. It is the cheapest and best defense against stripping solvents. If you are stripping cabinets or paneling above wood or vinyl floors it helps if you can easily remove base boards or even just the base shoe will help prevent damage to these surfaces. You can then mask off closer to the surfaces to be stripped.
First clean around the perimeter with a floor degreaser so that your masking tape will stick to the floor and not to the dirt or wax on the floor. Next use 1½” tape to mask the floors around the perimeter as close to the wood as possible without covering the wood. Now roll your plastic sheeting out and cut to fit around the cabinets. Cover the entire floor in the room or area you are working in. Tape this plastic down to the tape you have already applied around the wood to be stripped. Tape the plastic down in the rest of the room as necessary.
Next cover the plastic you have laid down with a layer of red rosin paper. This too is available in most paint / hardware stores. Red rosin paper will make the plastic safe to walk on with out slipping. It will also absorb liquids to an extent. The last layers of protection are canvas drop cloths again available in all paint and hardware stores. Use large drop cloths to cover the red rosin paper.
Now that you have the floors covered you are ready to cover kitchen counter tops, walls, appliances, cabinet interiors etc. Critical surfaces that may be damaged by the stripping materials should again be covered with plastic first. Brown 12″ hand masking paper on a masking machine is the easiest way to cover the plastic and other non critical surfaces. You may want to cover walls with two pieces of hand masking paper. This will give you 24″ of coverage away from the areas to be stripped. Stripping materials have a tendency to fly some distance from the immediate work area while using scrub brushes and scotch brite pads. Cover as needed.
Notes regarding masking tape: There has been a lot of money made by tape manufactures the last couple of years promoting expensive low adhesive tapes, i.e. 3ms blue tape. This tape is engineered to prevent excessive tape adhesion and consequent damage to underlying surfaces. These tapes are best used with water based materials and paints. They do not hold out the solvents of the strippers and lacquer thinners that we are discussing. The tape glue dissolves quickly with minimal exposure to solvents and releases the tape from the surface necessitating re-masking.
I recommend good old fashioned cheap yellow painters masking tape. It holds out the solvents better and damages the underlying surfaces the least. In my experience if tape is going to pull or lift underlying surface finishes, it is due to that underlying finish not adhering to the substrate below very well. In this event there is no tape that will prevent damage from excessive tape adhesion.
If you need to mask off porous surfaces like brick or stucco, masking tape doesn’t work very well. Use fabric or grey duct tape, then your other masking materials on top of that.
Now that you have your work area prepared the next step is disassembly of as many parts as possible. Cabinet and furniture doors, drawers and all there related hardware should be removed and numerically labeled so that all the parts and hardware go back in the same location during reassembly. Stamping wood parts in an inconspicuous location with numbered dye stamps works the best, i.e. behind or underneath hinge parts.
It may seem like a lot of work to disassemble these parts to this extent however you will find that working as many parts, flat / horizontally as opposed to vertically more than makes up for the additional disassembly time. Stripper and lacquer thinner have a greater chance of softening the finish allowing easier, quicker stripping / scrubbing when laying flat on the surface. These materials run off vertical surfaces quickly and require frequent rewetting to achieve the same results as when laid flat. In addition parts stripped and sanded horizontally end up cleaner and better prepared to receive the new finish.
All the lose parts may be stripped on an appropriate work table / bench in a well ventilated covered area. An easy and inexpensive work table can be easily set up with a pair of sturdy saw horses and plywood.
Now that you have your work, your work area and your self protected and ready for stripping, you are now ready to gather your stripping materials and tools accordingly.
1. Putty knives – 6″, 3″ and 1″ flex and stiff blades. You will use the stiff blades for only the thickest coatings of paint or clear finishes to be stripped. The flex blades are better suited for thin clear coatings on stained wood. Thick blades used aggressively can scratch and gouge wood surfaces.
2. Scrub brushes – Nylon and wire brushes. Use these brushes for scrubbing stripper and finish out of ornate detail that is difficult to get into with the putty knives and or red pads.
3. Red scuff pads. 3M makes the scotch brite brand of synthetic steel wool that is best suited for scrubbing and cleaning with the lacquer thinner and T.S.P. after stripping. (More on that later.) You can buy it in boxes of 20 that are 6″ x 9″. Frazee Paint carries them. A cheaper knock off brand is Mirka. They are sold at many automotive paint supply stores. You don’t want to use the “old school” steel wool. It is dangerous when used with flammable solvents as it can cause a spark and fire when rubbed over metal, i.e. electrical boxes, nail heads, screws etc.
4. Rags – Cheap painter’s rags for clean up.
5. Stripper or “chip” brushes. An assortment of cheap brushes, 1″ to 6″ wide.
6. Buckets – 1 and 2 gallon buckets to work the stripper and lacquer thinner from. You will also need a couple of 5 gallon buckets with lids for your slop, (Stripper and lacquer thinner residue.) and your dirty rags. It is important to keep this and your slop bucket covered with the lids to prevent a fire.
7. Card board boxes. Assortments of small boxes to scrap and deposit the paste stripper into after you have scrapped it off the surfaces you are working. Shoe boxes work great.
8. Stripper –
9. Lacquer thinner. Any cheap brand will do. Sold in paint stores in 1 and 5 gallon quantities.
10. T.S.P.- Trisodium Phosphate is a water soluble heavy duty cleaner that you will use to scrub and clean the stripped surfaces after scrubbing with the lacquer thinner. It is also readily available at most paint and hardware stores.
You are now finally ready to commence stripping !
One of the biggest mistakes amateur wood finishers make when stripping furniture and cabinets is to commence sanding with coarse grit sand paper immediately after using the paste stripper. What occurs in this case is that the finish and stripper residue including all the wax, silicon, dirt, grease and grime that was on the surface is ground deeply into the pores and fibers of the wood. This yields a dirty surface to apply the new surface finish too. This is especially critical with transparent stain finishes. Staining surfaces stripped in this manner often produces an uneven, blotchy appearance. Even if the surface is sanded to an even appearance there will be containments remaining in the pores of wood that you are unable to remove with surface sanding. These contaminants may prevent the new stain from penetrating the surface evenly. In addition the new clear or paint coatings may not adhere as well to these contaminated areas. They also cause other finishing problems like cratering or fish eye.
You may have by now come to realize I am suggesting a multi stepped stripping process that includes a thorough cleaning and scrubbing of the surface after the stripper has done its job of removing the surface coating. This cleaning is done with lacquer thinner first then TSP. These three steps should be done in succession before the solvent or cleaning solution of the prior step has dried out.
As the stripper dissolves the surface finish, the chemicals of the coating and stripper / cleaning solvents are wet at this point and in solution. If these chemicals are allowed to dry, you will then have to use a lot of chemicals, (stripper, lacquer thinner or TSP) to get them wet and back into solution again for removal from the surface.
I recommend processing no more surface area than you can work before any one section begins to dry out with the stripper, lacquer thinner or TSP. Work one area at a time with each stripping / cleaning material in immediate succession. The secret is to keep the surface wet with these materials to allow them to do the work as opposed to you using your very expensive elbow grease to force the finish off.
With gloves and safety glasses in place, pour only as much stripper into a one or two gallon bucket as you will use within one hours time. Use the appropriate size chip brush for the size of the work you are stripping to liberally apply the stripper to the surface. Get it wet and keep it wet with reapplications until the finish is bubbling and blistering, usually within ten minutes. If the stripper has not caused the finish to bubble and blister before it dries continue to re-wet the surface with stripper until it does bubble and blister.
Now comes the funest part of the whole process. Use your putty knives to scrap the stripper, clear finish and or paint film off the large flat surfaces. If the finish is a heavy varnish, polyurethane or old enamel paint coating it will peel off the surface in sheets and big chunks. Deposit in one of your card board boxes for disposal in the trash after it has completely dried out.
Use the flex blade putty knives when at all possible to prevent coughing the surface with the stiffer bladed knives. It is easy to catch an edge with the stiff blades causing a gouge that will need excessive sanding or filling later. Use the stiff blades only for the most stubborn spots after repeated re-application of stripper has failed to easily remove the film with the flex blades. Never scrap or scrub the surface with putty knives or brushes so hard that you gouge or change the texture of the surface. This will require much sanding to smooth down and especially for stain finishes will change the color of the surface in these areas.
Your nylon and stainless wire brushes are used to scrub stripper and finish from detailed areas. The corner of putty or a dull pocket knife can be used to scrap finish and stripper from the deep crevices of detailed moldings. Be careful and work slowly with your scrub brushes as these are the moments when stripper is flying off the brushes and can easily lodge in your unprotected eye or land on unexposed skin. Cover up and wear your safety glasses / goggles.
When finished with the paste stripper for the day do not return un-used stripper back into the stripper can. This contaminates the fresh stripper, weakening and discoloring it.
After you have the surface finish removed at least 95 % it is now time to scrub and remove the remaining surface finish, stripper residue and all other surface contaminants. Again this is done before any one area of the surface you are working on dries out.
Pour about a gallon of lacquer thinner into a bucket. Use the red scuff pads dipped into the lacquer thinner to scrub the stripper and finish residue from the surface. On flat surfaces it is easy to flood the surface with solvent to easily scrub and clean the surface. On vertical surfaces just dampen the pad with the lacquer thinner as most will run down these vertical surfaces. One technique is to use a rag in one hand to sop up the lacquer thinner below the hand that is scrubbing above. Wash the wet rag back up to re-wet the surface as you scrub.
As you scrub you will notice a cleaning action on the surface. For pieces to be stained it is important that you scrub and clean all surfaces to an even color appearance. It is this scrubbing that will actually remove 90 % of the existing color in preparation for a new stain color. You only want to sand to remove the last 10 % of residual color and to smooth the surface in preparation for the new finish. Scrubbing with solvent is always cleaner and faster than sanding. For pieces to be painted it is only necessary to remove the residual finish and stripper residue.
The last step in the stripping process is to scrub with TSP. This is a water soluble heavy duty degreaser. It also removes mold and mildew. After thirty years in this trade, I have come to believe in this final stripping step after many bad experiences of finish failure over surfaces that were still dirty with finish, stripper, wax, silicone, dirt, grease and grime residue. You would think that an industrial grade solvent borne chemical stripper and lacquer thinner would remove all of the afore mentioned contaminants. However it is my opinion that many of these contaminants are simply moved around from place to place with these chemicals and not actually removed from the surface 100 %, especially deep in the pores and fibers. In the final analysis it is the final scrubbing step with TSP that actually scours the surface to remove and or neutralize the contaminants from the pores and fibers of the wood.
I have come to this conclusion with much consternation as it is a generally accepted principal that you should not allow water to penetrate raw wood surfaces prior to finishing. I can say that in the ten years I have been following this procedure I have experienced very few problems with veneer delaminating or solid wood parts warping or splitting. In addition this process has prevented virtually all of the problems associated with finishing over dirty surfaces. This has allowed me to eliminate the use of fish eye additives that are essentially contaminants added to finish coats to promote flow out of finish over contaminated surfaces, thus compromising the new finish with this new contamination.
Mix approximately two tablespoons of TSP in a half gallon of the hottest water you can stand to handle. Use your gloves and safety glasses as the TSP is a caustic solution. Scrub all surfaces with the red scuff pads just damp with the solution. It is not necessary or desirable to saturate the wood with the solution. Doing so may promote warping of solid wood parts and or veneer delamination problems. For surfaces that you know are still very dirty a second treatment with fresh TSP may be necessary. When scrubbing is complete and before the solution dries out, rinse all surfaces with the hottest water you can stand with painters’ rags.
You now want to allow these stripped and scrubbed areas to dry as fast as possible so that the water has little chance of damaging the wood. Fans in the area are good. Parts left in the sun to dry are great.
You are now ready to proceed with the three stripping scrubbing steps on the next area.
Parts that are fully dry a minimum of twelve hours will be ready for sanding in preparation of your desired finishing steps.
If you follow these stripping / scrubbing procedures you will not need to sand any where near as much, as if you used the stripper only, and then proceeded directly to sanding. For stain finishes this is ideal for saving the existing sun and age related patina of fine antiques, furniture and cabinetry.