KBM Problem: overheating pad backing

AudiOn19s

New member
Every time I try to do the KBM method using my PC I find that after a few panels the backing material on my pads is getting soo warm that it actually starts to melt to the backing plate.



I thought possibly the velcro was bad on the backing plate so I put a brand new backing plate on the PC and even using a brand new pad I'im still getting the same issue.



Anyone else having these problems? Maybe I need to try a different backing plate? Too much pressure maybe?...though I'm not stopping the head when applying pressure and when I ease up it doesn't seem like I'm really getting any results. I even had an issue melting a 4" pad as well.



There's quite a few instances where I'd like to use the KBM more but at this rate I'll just stick with the rotary!



Andy
 
Sorry for the missing detail.



I was using the Porter Cable hook and loop backing plate



Now using a lake country plate.
 
Does PC even make a velcro backing plate? The amount of heat also has to do with the pad (foam type/density) and of course there are different velcros and attachment methods, which affect how resistant they are to the heat. What pads have you been using?
 
I think what I am using is a LC BP and have never had this issue. How much pressure are you applying? Is the pad still spinning CW?
 
Setec Astronomy said:
Does PC even make a velcro backing plate?



Huh? Sure they do..oh, I think you mean "do they make a *4"* plate", right?



Last time I checked they only make them in 5" and 6" (and I can't seem to make sense out of my notes regarding their current part numbers :confused: :o ).


AudiOn19s said:
Too much pressure maybe?...though I'm not stopping the head when applying pressure and when I ease up it doesn't seem like I'm really getting any results. I even had an issue melting a 4" pad as well.



Noting that I'm the guy who always gripes about PCs just jiggling under pressure...



I can't apply that much pressure without messing up the DA motions (the same thing that gmblack3a is referring to). That's why I have to use 4" pads to get timely results.



And I don't *need* to apply that much pressure with combos like M105/4" orange. I've done a *lot* of correction via PC/4" and while I've worn out pads (the foam starts to come apart right above the velcro back from all the stress) from the pressure I do apply, I've never melted one.



I think you're overdoing the applied pressure.
 
Accumulator said:
Huh? Sure they do..oh, I think you mean "do they make a *4"* plate", right?



Last time I checked they only make them in 5" and 6" (and I can't seem to make sense out of my notes regarding their current part numbers :confused: :o ).



Er...I guess I'm just ignorant, I've only seen the PC sandpaper backing plates and the white pad-and-backing-plate that comes with the machine.
 
This sounds like what happened to me using my UDM, 3.5 inch backing plate, and 4 inch pads.



The velcro on my backing plate gets hot in the middle, warps or melts a bit, and lets loose from the rest of the backing plate.



After it happened the first time, I paid a little closer attention to the heat being generated, and it seems to get the hottest when running at speed 6 (full speed). Any speed less than that seems to generate significantly less heat.



I just continue to pay attention to how hot the plate is getting, and give the UDM a break when needed to keep the temps down.
 
Wow, melting velcro and backing plates?! :soscared:



I have intentionally avoided posting information about this method because there are soooo many reasons this method works. I think it is best to give a few pointers now, because there is a lot of misinformation and confusion about the procedure. I d not want newbies to try this method before using what is normally recommended!! NEWBIES- this is NOT for you!!! Until the paper is released, stick with the manufacturers recommendations if at all possible (with exception to the priming part- it helps every time I've tried it).



Luster... here you go!

While an increase in pressure is necessary, it is not the only factor that should be addressed when using the "method".



Proper priming of the pad is super important!

This one step will have more positive effect on polishing performance than anything else. Well, a clean pad is equally important.



Consistent pressure across the pad is key.



The pad should be rotating at all times. More speed is a good thing when heavy defect removal is the goal. This does not mean that slow rotation will not work. However- some pads rotate well while others do not. Oftentimes, if there is insufficient removal of defects even with a substantial amount of downward pressure, a swap of the pad to one that is more aggressive or smaller in diameter will work. The guys that are using smaller diameter pads to remove heavy defects are working smart- not hard.



After all the defects have been sufficiently removed, final polishing should be accomplished using the softest or mildest pad available, with a couple of caveats:



The pad must be able to accept firm pressure without marring the surface. If marring of the paint occurs, do a test spot by hand using a foam or microfiber applicator pad. Check your work. If the marring has been eliminated, the pad should be inspected for damage or contamination. If the pad is clean, it is likely that it is incompatible with the paint type when paired with the particular buffing liquid being used.



There is a lot of confusion pertaining to how much product should be used when using this "method".



In general, for defect removal

First, thoroughly prime the pad as shown here: http://www.autopia.org/forum/machine-polishing/116716-look-into-pad-priming.html

Add buffing liquid as needed, making sure to clean the pad prior to adding more buffing liquid. To properly clean the pad, lightly brush with a soft nylon bristles brush. Then use compressed air to remove stuck on debris, followed by a quick towel cleaning of the pad. To towel clean, hold a microfiber towel in one hand and press the pad into it while throttling the machine using the other hand for 3-5 seconds (or until the pad looks clean). For safety sake, a microfiber bonnet over a foam pad works great!



To hold the bonnet/pad combo, this type of applicator works great:

http://www.ferroind.com/pdfs/Ferro Industries, Inc Catalog.pdf (bottom of page 7, part number JPS-60)



For final polishing, prime the finishing pad as previously discussed, and let the pad sit for a few minutes. This will allow the buffing liquid some time to permeate the pore structure of the pad. Prior to use, remove a majority of the buffing liquid utilizing the towel cleaning method previously discussed. This will eliminate clumps of abrasive material and remove excess product from the pore structure of the pad (this way no added product will make its way onto the surface of the pad). At this point, the pad face should have a very consistently applied amount of buffing liquid. Then, polish at a slow speed setting, making certain that the pad is able to rotate (it does not matter how many rotations there are, the goal is to minimize the chance of "flatspotting the pad). Add small amounts of product as needed. That's all.
 
sorry I missed the updates to this thread.



To be more clear...the backing plates are not melting, however the velcro on the pads is what's starting to melt and only in the center as noted by one of the other posters in this thread.



I'm not stopping the motion of the head or pad when applying pressure however what I'm starting to think is the cause is too much time when applying pressure. I usually work the area 3 times and possibley my second and third passes I'm not easing up enough on the pads. I'll keep going with it and see if I can get better results without all of the heat.



Thanks for the input.
 
Kevin Brown said:
Consistent pressure across the pad is key...



Though tilting things, to concentrate the polishing on a small area, can be handy for really aggressive purposes, huh?



Thanks for chiming in on this thread, and for the Cliff's Notes too ;) Oh, and I think that caveat about the proper methods for newbies was a good idea. Best wishes regarding your ongoing efforts on the paper.




Setec Astronomy said:
Er...I've only seen the PC sandpaper backing plates and the white pad-and-backing-plate that comes with the machine.



The ones that come with the machines (5" or 6" depending on which model) are also available separately from PC. They have them with/without holes too, or at least they did the last time I ordered any from them. Nice high quality IMO, I bought mine as spares as the originals have simply never worn out. They're thinner and more rigid than most aftermarket plates, but hey..they still work fine for most applications.



Hm...wonder how they work if turned down to say... 3.5" :think:




SuperBee364 said:
AudiOn19s, are you using speed six?



Ah...good point. I always turn my PCs down to 4-5 for use with 4" pads, and it's sure not like I avoid being really aggressive about this stuff.
 
SuperBee364 said:
AudiOn19s, are you using speed six?



Yes on Speed 6 since the intent of trying the KBM was to cut with the PC. I don't feel it's very effective at anything lower than speed 6 with the 5.5' pads. Maybe I'll try the 4' pads again at a slower speed.



It's funny that I'm having a "learning curve" with the PC again after only limited use with it over the last couple of years. I'm finding alot more customers who want their money to go further even with detailing and I think the KBM via PC is a great way to provide that without a multi-stage rotary detail.



What I have also failed to mention is the results I'm getting are great...just need to refine my technique to not eat pads!



Andy
 
AudiOn19s said:
Yes on Speed 6 since the intent of trying the KBM was to cut with the PC. I don't feel it's very effective at anything lower than speed 6 with the 5.5' pads. Maybe I'll try the 4' pads again at a slower speed...



Hmm...with the larger pads I'm surprised you're having heat problems at "6" but eh...I never did all that well with ~5" pads so I wouldn't be surprised if you do better with 4" pads at speed "5".





It's funny that I'm having a "learning curve" with the PC again after only limited use with it over the last couple of years.

What I have also failed to mention is the results I'm getting are great...just need to refine my technique to not eat pads!



Well, different product (and perhaps pad) technology has changed things a bit. Wonder how you'll do with the smaller pads :think:
 
i too had similar overheating velcro issues in the middle of my 4" pads on speeds 5 and above on a PC using LC spotbuff pads w/ LC backingplate. ive also heard you arent supposed to use 4" LC backplates on speed 6, maybe that has something to do with it.



im waiting on the release of the paper since even though i read whatevers posted so far im sure im missing a lot of into and technique.

but so far with 105 on a yellow or orange 4 incher ive only got so so results with a PC. it finishes very nice but isnt doing much for deeper removal and correction. cant wait for the paper to come out so i can read it religiously and get busy. otherwise i gotta go for a flex orbital or a rotary.
 
jaynick808- Welcome to Autpopia!



Re your less-than-swell results with the PC/4"/M105...you might check that you're not using too much product. While the KMB seems to emphasize using plenty, too much can reduce the effective cut IME.



And note that it can still take many passes on really hard clear. That's one reason why I recently experimented with the yellow and blue *wool* 4" pads, which sure *do* help the PC cut paint.



But yeah...the Flex 3401 does the work in a lot less time IME.
 
I'm using a 6 inch LC backing plate and had it separate from the bolt that screws into the PC over the weekend. I was using it on speed setting 6. I bought this pad because it was rated to handle the speed of the PC. I'm sent the vendor an email to see if they can do anything for me.



I'm thinking about getting a heavy duty backing plate I saw on Autogeek.
 
nydog said:
I'm using a 6 inch LC backing plate and had it separate from the bolt that screws into the PC over the weekend. I was using it on speed setting 6. I bought this pad because it was rated to handle the speed of the PC. I'm sent the vendor an email to see if they can do anything for me.



I'm thinking about getting a heavy duty backing plate I saw on Autogeek.



Welcome to Autopia!



Was it the Porter Cable brand backing plate? IF so, it might be one designed for holding a sheet of sandpaper and for use with no applied pressure. (Porter Cable didn't design the original "PC" with car polishing in mind.)



Maybe you just got a defective one :nixweiss



Or else you were applying a lot of pressure for a large plate/pad. Whenever I apply much pressure to a ~6" pad the PC merely "jiggles" instead of doing full dual-action motions (because the rotation isn't mechanically driven).



Huh...your problem has me kinda :think: as I've just never had problems with the larger backing plates. Hope you get things resolved pronto. Since all my large PC plates work fine I bet you'd be happy with the ones from AutoGeek.
 
Seems obvious but I'll ask anyway - are you using a washer between the machine and the pad? A couple of years ago folks here went through a 'melting plate' phase and attributed it to not using a fiberboard or cardboard between the plate and the machine. Too much heat transfers from the machine into the pad mounting screw if the washer isn't there. IIRC, cheap cardboard washers can be found at Lowes. I got a washer made from circuit board material with either the backing plate or the PC, I don't recall which.
 
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