Flex 3401 generates a lot of heat?!

**erichaley** · 06-10-2013, 09:13 PM

Of course they didn't, plastic and especially foam are excellent insulators.

**allenk4** · 06-10-2013, 09:53 PM

I have experienced pads and backing plate getting very hot on my PC 7424.

It happens when I get too much product on the pad and use excessive downward pressure.

Enough to melt the adhesive on a 5.5" LC Purple Foamed Wool Pad.

**mbret2004** · 06-17-2013, 08:18 AM

according to Flex the tool monitors for overload/overheat conditions. If the Flex is having the mentioned issues it automatically slows the RPM until it cools to a pre-determined temperature. So, if it's not dropping RPM on it's own one is led to believe it's o.k.
I'm assuming the overload/overheat monitor system in the tool is functioning correctly.

**erichaley** · 06-17-2013, 08:25 AM

I've been noticing my Flex 3401 VRG getting hot lately as well. I took some temperature readings with an infrared thermometer shortly after using it for awhile, and both the housing and backing plate were around 130 degrees. I'll try to put together a specific, repeatable procedure with temperature readings so that others can try it as well and report their findings. If anyone has any input I'd welcome it.

**erichaley** · 06-17-2013, 08:42 AM

One other thought... I saw it mentioned somewhere before that using an extension cord that is too thin or too long (or both) can cause a polisher to run hot. For both those that say their Flex is getting hot and those that say it isn't, describe how your polisher is plugged in. I listed out the questions to make it easier to quote this message and add your responses.

1. Which cord does your Flex have?
a. Standard cord
b. Optional extended cord

2. Are you using an extension cord??
a. Yes (length and gauge?)
b. No

3. Does your Flex get hot enough that you can't hold your finger to it without feeling like it will burn you (please don't burn yourself)?
a. Yes
b. No

**Calendyr** · 08-22-2013, 08:21 AM

You beat me to it Erichaley, if the extension cord it not rated for a 7.5 amp motor, one of the side effects is that the motor will heat up. Or so I read somewhere...

What would be the best Backing Plate to use? I know some of the BP have holes in them to reduce heat transfer. Which one do you guys use?

**loudog2** · 08-22-2013, 08:29 AM

Originally Posted by Calendyr

You beat me to it Erichaley, if the extension cord it not rated for a 7.5 amp motor, one of the side effects is that the motor will heat up. Or so I read somewhere...

What would be the best Backing Plate to use? I know some of the BP have holes in them to reduce heat transfer. Which one do you guys use?

I have been using my 3401 for years now without issue. Yes it gets a little hot sometimes. Make sure you use the right extension cord and lube the felt ring a little.

**richy** · 08-23-2013, 09:58 AM

I lubed my ring (Gosh that sounds weird all on its own...) the initial time. Mike had a thread about doing it with pics and whatnot. I'm wondering if it needs it periodically, and if so, how often?

**loudog2** · 08-23-2013, 03:13 PM

Originally Posted by richy

I lubed my ring (Gosh that sounds weird all on its own...) the initial time. Mike had a thread about doing it with pics and whatnot. I'm wondering if it needs it periodically, and if so, how often?

Just not too much or you'll go blind

Someone in another thread said the issue was fixed with new models. I have a old model so I will still lube since it doesn't hurt anything. Like Ron(rsurfer) said "I can see the friction marks on the backing plate from the felt ring. With friction there is heat". I agree with the statement fully. I usually lube mine twice a year depending how much I use it.

**mbret2004** · 08-23-2013, 09:38 PM

Originally Posted by mbret2004

Agree with Dave. Anytime you have friction you will create heat. Aluminum dissipates heat rapidly hence the choice on the Flex. Many car engines have aluminum parts for the same reason.

Personally, I would use the tool without worry. Be aware it gets hot and handle accordingly.

Maybe I spoke prematurely on this issue. Using my Flex a few weekends ago I had a malfunction. The plastic pad mount actually became dislodged off the machine. The plastic retaining boss that sits below the allen bolt and washer, which is part of the pad mount, actually melted resulting in the pad mount coming off the machine. I was using it doing some paint correction. This was the second vehicle I used it on since purchase.