by Bob Beranek

glassBYTEs recently posted a request for information on induction tools for glass removal. I thought I would throw in my two cents. I plan to address this by first explaining how the tools are supposed to work and then some observations I have had over the years of using the tool.

Basically, an induction tool uses an electromagnetic field to gyrate metal molecules to create heat. It works by heating the metal to a temperature that allows the separation of the paint coatings from the primer coat. The primer coat has a higher tensile strength than the paint so the paint layers will separate faster from the primer coat.

Any metal in, on or touching the glass unit will heat to temperatures that can melt, burn or deform attached moldings. The glass itself and vinyl moldings will stay cool, but any substances that touch the metal can be damaged unless steps are taken to cool or remove the parts.

So, is it safe to use on auto glass removal? There is a debate for and against induction and I want to give you my thoughts and open it up for discussion.

Induction tools may not be the best choice for all glass parts on a vehicle. I have tried using induction tools on windshields and other laminated parts. In my opinion, the time and effort expended was not worth it. In addition, the chance of breaking the laminated part is increased because greater pressure is applied to the glass and that can cause fracture. I also have safety concerns about the high temperatures applied to the windshield pinchweld.

However, I feel that using the induction on quarter or back glasses or stationary vents bonded to steel pinchwelds are not as much of a safety concern as the windshield area. You can add much more pressure on tempered glass than laminated and you can separate the glass from the body well before the metal is weakened or damaged.

To use the induction tool properly,

  • I recommend two people, one to run the electromagnet around the glass part’s perimeter and one on the inside applying pressure.
  • The interior garnish moldings and other parts that touch the pinchweld area must be removed from the vehicle and set aside.
  • If the glass parts have antennas or any electrical systems attached to it, find another way of removing the part. I would not recommend induction for removal.
  • If the vehicle has an aluminum body, I would also find another way of removing the glass.
  • Make sure to remove any jewelry or metal from your hands while using the tool. A ring, for example, could burn your skin and cause injury.
  • While running the electromagnet around the perimeter, have the helper apply pressure in one of the dull corners of the part using the flat of a gloved hand. Sprinkle the perimeter with water while running the tool. This cools the surrounding moldings and paint.
  • Once the corner separates from the metal, run the tool and have the interior pressure match the tool’s movement. This should separate the glass from the body leaving the primer coat intact on the body and the paint and clear coat still adhered to the urethane bead on the glass.

Usually the reason you would use an induction tool is for salvaging the glass part for reuse after body work is completed. One of the complaints with the induction tool is that if not used correctly, it can burn the paint or melt the moldings where you don’t want it burnt or melted. This is a possibility, and the customer should be made aware of this eventuality. However, if you use the sprinkling of water while using the tool, the chances of this is reduced and possibly eliminated.

If we look at the bonding chain of glass adhered to paint; we have to understand that aftermarket paint jobs can never replicate the OE paint job in terms of strength. It is impossible to bake the paint to the metal at the temperatures the OE can achieve. The OE has nothing but a frame to bake but the collision center has the vehicle almost completely together with plastic, fabric and other flammables. It can only take so much heat.

Now to the question of safety, the total bond is only as strong as the weakest link in the bonding chain.  If the weakest link is the aftermarket paint job, then any failure would occur at that point.  Remember that you should be bonding to the primer coat and not to the color coat because the primer has a higher tensile strength than the color. If you refrain from using the induction system in the windshield area and only use it on side or back parts, the chance of injury due to the use of the induction removal is slight.

Does it work? Yes. Does it cause damage to paint or other parts touching the metal? It can if precautions are not taken. Does it damage the pinchweld? I don’t know. That is a question that should be asked of a metal expert. Is the removal of an expensive glass part with an induction system worth the time, cost and energy of the collision customer? That question you will have to ask your customer.

All right readers, what do you think?

Comments (7)

  1. Pat Frey said on 28-11-2012

    As an auto glass distributor I have had 2 requests by retail glass shop customers wanting to purchase this tool. In both cases they experienced expensive learning curves. On the first job of each customer they managed to cook the paint on the roof line of the vehicles they were working on. One was removing a backglass the other a windshield. After some inquiries to the manufacturer it was recommended that they apply welders gel around the outer perimerter of the glass part. As Bob states in his article, even when done properly the paint is completely removed from the bonding area. I feel this tool is best suited for a wrecking yard that wants to remove glass without breaking it and isn’t concerned with re-installing the part.

  2. jamie bark said on 28-11-2012

    Hi Bob, I agree completely… I was pulling a qtr out on a newer Durango in a body shop… slammed tight to the pinchweld. Actually burned/ discolored the white pearlessent paint before the part even loosened up. Fine for salvage vehicals, not so much for agr. I have saved some moldings that are glued on though on some pretty fancy cars.
    Appreciate your insights,
    jamie @ Glass Doctor in Hudson

  3. Daniel Dinu said on 28-11-2012

    While i improve my skills in Germany, I had the opportunity to use the item issued by OTC.
    Although the promotional video looks very tempting, the reality proves to be a little more tricky: very high experience and skill is required and extreme caution must be carried on.
    For quarter lites (mostly encapsulated), it is a great asset, but for regular windshields and backlites, I would recommend the classic cut-out methods.
    Note that once heated, the steel frames / pinchwelds might change the molecular structure, more than that: the recent glued joints reinforcemenets might be affected.
    To cut a long story short, I suggest extreme care whilst using heat as cut-out method.

  4. Daniel Dinu said on 28-11-2012

    Note that in Europe, such a machinery is extremely expensive and most of the promoters are far, far away from the cruel reality !
    The very first salesman whom I urged to explain practically the use of such a device, needed about 40 minutes to understand himself how does it works…
    You draw the conclusion.

  5. Chris Donaldson said on 29-11-2012

    We have been considering adding magnetic induction For some time now. It is one of the technologies that we had hoped would be showcased at auto glass week in Kentucky this year. Unfortunately, there were no vendors demonstrating or showcasing magnetic induction. We did, however, meet a trade brother who had used magnetic induction to remove a front vent glass on a Toyota. The plastic clips that help to align the vent glass with the pinch-weld Caught fire when they melted away from the glass and fell within the body of the vehicle. The flaming plastic pieces fell on top of expanded polystyrene insulation within the door and caught the vehicle on fire causing $6000 in fire damage to the ride.
    Your blog is insightful with regard to things that must be considered regarding the bonding chain.
    Is it worth the risk to use magnetic induction?… Many of our body shop account holders think so. For this reason it will still most likely be a tool we add to our repertoire.

    Chris Donaldson
    W&W LLC

  6. Mitch Becker said on 29-11-2012

    I agree with Bob.
    Induction heaters I would not recommend for glass removal. Yes, it does remove the glass and sometimes, in very qualified hands, it is a tool for some jobs. However, in the auto repair industry, their is a big picture to see. I won’t explain how the tool generates heat, to make this comment as short as possible. When heat is generated on the metal, it transfers to the urethane bond and causes urethane to release at the bond line. The problem is that many times the paint and primers also release. This will require a complete repair of topcoats of primers and paints to bare metal as their bond to the steel have been compromised and corrosion protection is lost. Even if the primer did not pull up while removing, the heat will have caused a reduction in the tensile strength of primer to metal. The problem does not end there. The heat also transfers to the backside of the steel being heated, burning the primer and paint in between the panels as well. This again compromises the corrosion protection of the vehicle. On vehicles that use weld bonding or welds with adhesive to bond panels. The heat releases the adhesives holding the panels. This requires panel to be removed and re-attached to maintain structural integrity in a crash of the occupant compartment. Although the welds are still there, the adhesive is critical to prevent flexing and metal fatigue during everyday use.

    If removing a windshield or backglass and the roof is bonded to vehicle with adhesives only and no welds are used, as is being used in many new vehicles, then congratulations you are half way done in removing the roof along with the glass.

    One other problem I will address and certainly not the last one possible, is the use of High Strength Steels and Ultra High Strength Steels in the areas being heated. Heat created by the induction tools desroys the strength of these steels which are all layered and welded together at the pinchweld right where the heat is applied. This will have severe impact on vehicle strength and integrity.

    • Gene Shrock said on 21-10-2013

      I am like a lot of you I have been fighting this because of all of the negatives that were described above, I have even gone as far as contacting I-car and questing them to how they can allow this to be an approved procedure. They responded that as long as it is used with in the MFG guidelines of the tool it is exceptble procedure. I even had paint MFG question heating up the pinch weld so much and what that would do for adhesion etc. Also what about weld bond panels? But all that being said there is a glass shop here in my market that very efficiently and effectively uses the induction tools regularly and has a huge amount of body shop accounts, so I now question myself am I a fool for not bring this tool into our shop for use? FYI I agree it should only be used on tempered parts.

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.