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New Project: Infrared Paint Remover: V2

A modern method of removing paint from wooden surfaces is the use of infrared rays. This method has gained popularity over the past decade as an alternative to mechanical and chemical methods of removing paint. Mechanical methods such as sanding, grinding, or shaving usually increase hazards such as lead dust. Chemical solutions minimize the lead dust but result in a gooey mess that requires cleanup and more chemicals for neutralization. Infrared paint removers ofter an alternative which minimizes dust and eliminates chemicals. When exposing a painted surface to infrared rays, the rays penetrate the paint, warm the substrate below the paint, thus releasing the paint’s grip. In practice, the infrared paint remover (IPR) held over a painted spot will cause the paint to slowly bubble and lift, making it easy to scrape it off with a scraper. IPRs are seen most often used by people restoring old houses or windows. They are, however, increasingly seen used in a variety of applications. The disadvantage of an IPR is that it is not guaranteed to be effective in every situation. See the conclusion of this article for more detail. IPRs are most effective on thick layers of old paint, especially aligatored paint. They do not work well on calcimine, milk paints, and will not remove shellac or varnish.

Note that IPRs are not the same as "hot plates," which heat paint via convection. Hot plates scorch and boil the paint through proximity to a heated element. That method risks scorching the wood substrate and releasing toxic gases. IPRs rely not on convection, but mostly on radiation. The goal is to penetrate paint and warm the substrate (wood), releasing the bond between paint and wood, slowly, without raising the temperature high enough to vaporize lead. When you stand at a sunny window on a cold winter day, and you feel the sun’s heat on your face even though the air outside may be zero degrees, you are being heated by radiation. In such case, energy is transferred directly to you and not via physical contact with an warmer object (conduction), nor using air as a carrier of heat (convection).

In August of 2004, frustrated at the high cost of commercial Infrared Paint Removers ("IPRs"), I cobbled together a home-made unit using a quartz heater and some miscellaneous hardware. I wrote up a small page outlining my experiments for the benefit of other old house restorers out there. The response was unexpected. It seems there are many out there like to tinker, save $, and DIY.

Here now is Version 2 of the IPR. Having traded my original scratch-built quartz unit for a Herbeau fireclay sink, and in need of an IPR, I elected to investigate this new and promising modality of paint removal: ceramic infrared.

Theory:

Commercially sold IPRs use quartz rods to generate infrared rays. My unit would be based on a ceramic emitter instead. Why ceramic? One reason is that a ceramic unit would be easier to build with fewer parts. Commercial ceramic emitters are readily available. Efficiencies for ceramic emitters run from 85 to 96% whereas quartz ran around 60%. Therefore, a higher percentage of the energy supplied to the unit would be transmitted as infrared rather than light. Quartz rods tend to have infrared hotspots. Cermaic on the other hand, produces a more evenly distributed heat.

The Unit:

Anyway, yet again, this is the time to point out some safety issues and make a disclaimer. Making your own IPR involves electricity. The project involves wiring as well as drilling, sanding, and cutting. (jeez doesn’t sound too bad) I am not advocating that you run out and build one, I am presenting my method here for your review. If you do make one, you do so of your own accord. If you electrocute yourself, or burn your house down, well, hey, that’s life, and your own responsibility. I am comfortable with the potential hazards. You may not be, and I urge that if you should make one anyway, you proceed with safety in mind and a good dose of common sense.

Thus my intention to build a new, ceramic based, IPR for the same or less money.


  • Dave

    Hi. Yes I wrote version 1 as well. That unit used quartz tubes. There are several concerns with what you propose. You can judge whether they are important to you. One is safety; if the unit stands by itself, you will most certainly be tempted to set it down. If you absentmindedly leave it sitting for more than 30 seconds or so you risk fire and/or scorching the wood. Even when turned off the unit needs minutes to cool to safe levels. A unit that cannot be left in a dangerous position wont be. Another concern is the legs , especially 4 points, scratching the wood. The legs get real hot, and it’s easy to make “snail tracks” or brandings in the wood if you’re not careful. I typically remove the risers altogether when working so that nothing touches the wood. Another concern is that you typically should use this device vertically rather than horizontally. When vertical the device absorbs far less of its own heat. I worry a bit about horizontal use for extended periods. Fortunately, unless you’re doing a floor, most work can be positioned vertical. Lastly you mentioned weight. Every ounce really does count when holding this thing vertically. If you can be mindful of these risks and warnings, then you can perhaps experiment with some trestle style legs. –Dave

  • casey.gonzales1@gmail.com

    Can you tell me how you built the infrared tool that you built first. I am interested in infrared not ceramic.
    Thanks,

  • MIchelle

    HI Dave — In case you check in, I would also love if you could post or PM the first set of instructions. I found and bookmarked them on the Ocean Manor page like about 2 years ago or something close. And I bought the stuff I need to make V1, incl the infrared heater (the ceramic is – I think – going to be too heavy for me to use effectively). Just never have had the time to put it together, but with spring approaching it is now a top priority to get my exterior painting done, and I have a garage covered with lead paint that I cannot get anyone to touch for a reasonable price. And now them website seems to be gone. Along with it, V.1 of the stripper. I recall that you discussed in pretty good detail how to deal with removing and re-seating and wiring the infrared tubes Sure could use that guidance again. If you get this, and can shoot me an e-mail, I’d be ever so grateful to you for your help. — Michelle mpaninop@gmail.com

  • http://newinnarberth.wordpress.com mpaninopoulos

    Oh look! Some amazing person made a pdf of your previous instruction and posted it. http://www.broadwaydistrict.org/paint%20Remover%20Instructions%201.pdf QUICK run to print it off before it ends up vanishing. And God Bless the Interwebz! And thanks again for working this all out and posting it for the rest of us. A great public service.

  • Christine

    Have you done any temperature testing of the hot paint? Is it over 1000 degrees F? Is it safe and doesn’t vaporize the lead in most pre-1978 paint? Would you tool pass any electrical safety testing? Beware.

  • http://www.singularpainting.com Andre

    I think small piece of aerogel insulating blanket past reflector will protect aluminum body from heat. I know about IPR for a long time, however good it can be for a home owner, the liability starting a fire keeps me from using it. I worked on many old houses and sometimes siding insulation can be 100 y.o. dry hemp ropes , paper dry as gunpowder etc.
    I will try to make IPR just to use on contured window frames/sash. For the siding, nothing works faster ( but requires skill) then Paintshaver. With powerful 2HP vacuum, Most of the residue is sucked into it . There are some tricks to make wood unclog after sanding , then
    it is ready for primer. Either way sanding wood after removal is a must because it removes
    all residue from top of the surface.

  • http://www.singularpainting.com Andre

    OK I forgot to tell you folks that I saw some aerogel pieces on ebay…. It is not cheap though but the latest technology in insulation

  • http://www.singularpainting.com Andre

    I also found those ceramic elements on ALIBABA and they are way cheaper there but unfortunately, sold in bulk…

  • http://www.singularpainting.com Andre

    Hi there! I just received the body part and it seems that heat conducts through the body of the unit by the contact with the reflector. Two rows of assimetrical holes into the aluminum part that skirts the reflector will decrease surface of heat transfer from the reflector. There is a heat reducing channel on outside edge of the aluminum skirt but there is still significant contact with aluminum frame. Perhaps strip of silicon tape will help? Any ideas???
    I also think that instead of aluminum tubes hiding the handle’s bolts rigid plastic tubes to be used further adding to insulation of handle from the body. Most of the weight comes from aluminum sliding lid part. But I would not drill any holes into those parts hence they isolate electric circuits. Also I would insert thin aluminum foil under the holes made in the skirt to prevent any posibility of moisture getting in there. Aerogel should arrive tomorrow and I am excited to finish the product coming weekend. Any ideas on thin insulating tape that resistant to high temps?
    Regards
    Andre

  • http://www.codegusto.com Robert

    My house was built in 1960 and is mostly brick with the exception of the trim work and wooden garage doors. The garage doors and all the trim around the garage doors are in especially ugly shape. The paint in these areas looks like alligator scales that are very thick and too hard to try and scrape. I ordered all of suggested parts for this Infrared Paint Remover V2 [went with the 1000 watt version] and I put everything together as outlined in the steps. I can say that the Infrared Paint Remover V2 does work because i was able to successfully heat and strip the paint on one of the vertical posts that surrounds the garage door. The post was successfully stripped of its alligator scales all the way down to the wood and then primed for paint. With that said, I must also say that the amount of time and effort it takes to do this is way beyond what I was hoping. It took me over six hours to do the one post that is roughly eight inches wide and eight feet tall. I received many eye rolls from my wife, but I was determined to have the new tool work. And although I can say that it did work, I must also say that I have admitted defeat and I will be replacing the garage doors and trim work that have these alligator scales with new trim pieces and new garage doors.

  • Christine

    Handy people: Yikes! You are taking risks with yourself, your homes, kids, and neighbors. Dave, why are you not warning them about high heat, wiring and wood fires, lead-paint toxicity, and other serious safety issues? You publish world-wide and have a disclaimer, but it’s scary that you encourage experiments with dangerous materials. I know I’m a skeptic and am discouraging good ole American ingenuity, but please folks know what your are messing with. Read up on lead-safe work practices at http://www.epa.gov/lead .

    • Dave

      I work from the assumption that people are neither stupid nor ignorant.

  • http://gravatar.com/mnphysicist mnphysicist

    Christine, I’d be very leery of using surface temperature as a means of determining lead emissions or not when using radiant heat transfer. There are a multitude of ways to get errant surface temperature readings (more so with quartz tube emitters than ceramic) and there may be many other factors at play when it comes to lead emissions. One thing that’s interesting about this mod is its vertical orientation, in that it should generate a convective plume which would should keep the lead emissions further from the operator than its predecessor. Bottom line, It would be interesting to look at various paint profiles and related lead emissions for both quartz and ceramic infrared heating methods…. but I’m not quite sure how to take something like that on without significant lab gear.

    Andre, Kapton tape is super thin and much more heat resistant than Silicon tape… but its so thin if might not be all that helpful for where you are trying to use it. What you might try is some silica mesh (McMaster sells it in small quantities), or if you have enough space some Kaowool.

  • Bob W

    After looking into the brand-name IPR’s and both DIY ones, I am very glad to have gone the route of this particular version. Mor Electric typically has an expected lead time of 4- to 6-weeks on the parts purchase, but they were able to expedite my purchase once contacted. Still having concern for my knuckles (I’m pretty accident-prone), I fixed a flat trowel in place instead of the hardwood handle. This gave me a flat surface to lay the unit down, has had no heat transfer to the trowel plate, and the handle grip is molded for a hand. I’m also hoping the rectangular trowel will make mounting onto a stand more stable. Here is the unit:

    It has performed very well so far, cleaning 3-4 layers of paint from my garage, though the clapboard cleans more easily than molding. Thanks for the great plans!

    • Bob W

      Another attempt to post the image location…
      [IMG]http://i42.tinypic.com/2wgdnqp.jpg[/IMG]

  • John Hufana

    Can someone post the actual part numbers at MOR Electric? I found many different models of the 750w 120v ceramic emitters and am unsure which one to get.

    • Doppledunkle

      I bought FTE-750-120-TW-L6-WH-0 120V 750W

      • John Hufana

        Thank you! Can you also give me the part numbers for the rest of the parts needed from the electric company? There are so many model numbers for each and every part I am unsure which ones to order.

  • Dave

    How hot will the paint get? Depends not on how hot the emitter is. It depends on how fast the work at hand disperses energy, which depends on other things….

    The surface of the emitter can be well over 1000 degrees. If you place the emitter on the paint surface, the surface will be 1000 degrees. If you place the emitter 1 mm from the surface, the surface will be very close to 1000 degrees. As you back off even more, the surface temperature drops, and ultimately depends on:

    -species of substrate wood
    -its moisture content
    -the type of paint on the wood
    -the thickness of the paint layers on the wood
    -the color of the paint
    -the length of time the IPR is held in one place
    -and the distance the IPR is held from the surface.

    This makes it difficult to judge exactly what temperature the IPR will bring the paint and substrate to. This is because each job is different. The ultimate temperature achieved is based on those factors, especially the last two.

    So one guy who holds his IPR 3″ from the paint for 20 seconds, is going to have a different temperature than another guy who holds the IPR 4″ from the paint for 20 seconds, assuming the same paint surface.

    The best way to approach this is to simply heat the paint just long enough to scrape it off. Hold the IPR just close enough so that it will soften in 10-15 seconds, no closer. Most paints soften between 200-400 degrees. I remove paint from hardware by boiling the hardware. In that case, we know the paint was 225 degrees.

    There is some information on the web that lead paint releases lead vapor at some magic temperature, usually stated around 725 degrees. I have never found the source of this number. And I’ve looked a long time. I believe based on something I read long ago that lead sublimates as the temperature rises, that it does so proportionately over the entire range of temperature, and not all at some magic temperature. I could be wrong, but I think it’s best to be cautious at all times.

    Dave (OP)

  • Dave

    To Robert:
    You are correct in your findings that the IPR is not a tool that suited for speed. It is more suited for quality of work. The IPR is best used for intricate or relief detail that needs to be reclaimed, small jobs where quality is important, or historic applications where conservation of the material is paramount. I doubt I’d use it on anything larger than a door. The IPR is not the best tool for large flat surfaces such as the side of a house. In such a case, sufficient results can be obtained with other methods. I used my IPR to do the trim of my house, but found it more cost/time effective to replace the clap boards. I have seen people use the IPR for typical peeling paint on houses, this is not necessary! Paint only need be removed if it: 1. is so thick it hides historic detail. 2. So thick (alligatored) that it will never be a good base for successive coats. 3. The original work was varnished/shellacked and it is desired to return to that finish.

  • Deirdre

    I simply bought a small quartz heater from Walmart (24.95 on clearance) and it works like a charm. Unfortunately, it has a small width of heating efficacy (6-8 inches at a time), but it does cover two clapboards on the vertical at a time. My house was built in the early 1900s and has a variety of paint applications on it, running from seriously alligatored four layers of paint to bare wood, and while I work at thirty second intervals to be sure I don’t scorch the bare parts, the job it does is truly remarkable. I admit, it would go a lot faster if I bought the professionally constructed setup,, but I’m on an extremely tight budget this year, and as a woman doing her own projects I appreciate the light weight of the heater I have. .

  • http://www.steadblast.co.uk/ Shot Blasting

    Infrared paint stripping is by far the gentlest process on the wood; particularly beneficial for listed properties where the preservation of the original, old wood is desired. The infrared heat penetrate into the wood and actually pulls up the normal resins deep in the wood to revitalize it. It also pulls up the paint or varnish which has sunk into the wood allowing them to be scraped off more thoroughly. The heat removes extra moisture deep in the wood and neutralises mildew and fungus. Yet, the lower temperature of 200-300pC minimises the risk of scorching or the wood catching fire.

  • Lawrence

    How does this ceramic diy compare in performance with the commercial model? I see people zipping along in the videos with the name brand but some of the reviews here are down right painful.

    If it under performs is it because the heating width is not large enough? Or people are not using the right pull scrapers.

    The dimensions of the Alex-F AI Extrusion Assembly 1 (MOR Electric item code IRALX10001)
    are 10″ x 3.88″ whereas the name brand is 14.5 ” x 7 1/8″ x 6 2/8 Heating area: 12″ x 5″

    Can this ceramic version heat an area 12″ X 5″?

    I need to strip partially strip a large church over time so I am interested in seeing this discussion continue. I’d also like to see some ideas on making a DIY hands free articulating arm. Looks easy enough but more heads are better than one.

  • james daniello

    i built this unit and had problems with the cord melting where it touched the aluminum housing. I fixed it by using “rescue tape”, a silicone stretchy tape. i simply wrapped the end of cord that went into the wire clamp with about a quarter inch in thickness with the silicone tape and clamped it in. works like a charm. you can find the tape at most hardware stores these days.

  • David M

    Dave, I just wanted to thank you for taking the time to share your build. I am following in your footsteps and building my first unit this week.

    • Mark

      Did you end up building it? How did it go?

      • David M

        Hi Mark,

        Yes I did and it went perfect. I ordered the parts as listed (750W vs 1000W element) and just followed the instructions. The unit works great. I live in a 110 year old Victorian house and have used this new device to strip paint back to the original wood trim including lead based layers. I elected not to add the sides as I prefer to control how close I hold the unit.

  • Mark K

    Would an inexpensive toaster oven work if you added a handle and spacer? Seems easier than building one from scratch.

  • Mark K

    I went to Walmart and bought a Rival toaster oven for under $20. I gently removed the glass door without damaging the spring loaded door closer, so the unit would stay on and send heat out the front. I held it up to my siding with the top and bottom heating elements on and the unit set to 450 degrees. The paint came off with a plastic putty knife, will work even better with a real scraper. The unit is light so I plan to make a handle of some sort, so I can hold it easily in one hand while I scrape with the other. We will see how long it lasts, but at $20 its basically disposable. I also plan to add some spacers to do a better job of directing the heat, will probably use the aluminum baking pan it came with for that.

    • http://twitter.com/matthewwanderer Matthew

      Hi Mark. Using a toaster is a creative idea. Are you still using it to remove paint? Have you pursued the modifications you mentioned above?

  • M. Twilly

    Hi. This unit sounds great and fairly easy to construct. Will it remove paint from a tubular metal handrail?? Does the substrate have to be wood for it to work?? Thanks. M

  • Ben

    How’s the Toaster working? Anyone else try this? May have to hit Walmart tomorrow and give this a whirl.

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