3" option for Porter Cable 7424

allenk4

allenk4

In time out
Joined
Mar 12, 2013
Messages
4,845
Reaction score
0
I thought I had it all figured out...

I have a FLEX 3401 with a customized backing plate for 5 1/2" pads, but I wanted something smaller with extended reach to get at the touch to reach areas that otherwise would require hand polishing.

I bought an adapter that allowed me to use a 3" backing plate for a rotary with Meguiar's Microfiber Pads.

WP_20131009_008.jpg


Worked well for a bit...then it overheated the backing plate and the pad; melting everything.

WP_20131026_008.jpg


WP_20131026_007_1_.jpg


I was using it on 5 with medium pressure, but I was working a small area for a relatively short period of time

It seems that the backing plate I used has a small "stump" that may be focusing the heat and causing breakdown?

Does anyone have input on a backing plate that might work better?

Results for 3" rotary backing plate - Search
 
What speed and pressure were you using? With 3" pads speed 3 and at most 4 is the most I use.
 
Medium pressure

Speed 5,

Meguiar's Microfiber pad

M105 primed with D300


On my older 7424 the pad will not even rotate at speeds lower than 5 if you put any pressure on it at all on a flat surface...even worse on a curved surface.
 
As you can see in the picture of the melted backing plate to pad interface...the heat seems to have been focused on the center of the pad, making me think that a different backing plate may yield better results.
 
I see your point...but when using a DA the product gravitates toward the center of the pad ~ at least that's what I've read countless times on pad failure threads. Failure comes from overheating the product which is centered in the pad.
I use that same bp on my rotary anywhere from 9-1200 rpm's with no issue. Heat transfer from the machine, or lack thereof is the reason I chose that bp. But then again, product gravitates outwards due to the centerfugal (?) nature of rotaries.
 
how did you do that?
gesh, I've had that set up for a few years now and have never done that.
you obviously worked it to long and fast and then it heated up
use speed 3-4 and work a small area for a few seconds.
 
I

M

O

​


Every once in a while you should give the machine a rest

Another thing that might help you is to gently remove the pad from the backing plate. If you can manage, wait 5 minutes after the last use

I

M

O

​
 
What the!? That's crazy! I've found that backing plates with holes work the best. Helps dissipate heat.

Still, I can't believe that combo produced that kind of mayhem. By relatively short period of time, do you mean 5 minutes in one spot? Hahaha

I've heated up some pads, but you've taken it to a whole new level, dude.
 
I use the same backing plate and I find it works quickly. I've not used MF pads with a 3" backing plate. I'm amazed you were able to build that type of heat. Try it again at 3.5 and use less pressure. Check the surface frequently for heat until you get the feel for it. Seriously that's impressive. I've found MF pads generate serious amount of heat when compared to foam. Have you noticed it takes a great deal of attention to keep the pad level with the 3"? I know it tests my abilities.
 
One possible answer:
(You had to have seen these posts in the Surgical Buffing article of Mike Phillips)

RZJZA80 said:
Are there any similar extensions/adapters for a DA? It would be useful to use a 3 inch pad with extension on a DA also, not just a rotary.

Mike.Phillips@Autogeek said:
Someone recently sent me the same question in an e-mail, another person via Facebook, here's the reply I sent via PM's


There is not one that I know of. I don't think it would work well with the PC type of tool, it would create too much leverage over the bearings and possibly cause harm.

DA Polishers use a 5/16" threaded stud while rotary buffers use 5/8" and there's a huge difference in strength when you start putting leveraged pressure or tension against the tool as it's operating.

I'm sure you can find some threaded tube stock at any Nut & Bold Supply Store, possibly a warehouse store like Lowe's but I don't think it's going to be good for the polisher and it's also going to make holding the tool tippy. My guess is it will also be harder to control due to the oscillating movement.

I'm all for someone trying though...



:)
Click to expand...
Click to expand...

OR:

That dastardly D140!! :D

Bob
 
Here is a picture of the area of the rear bumper that I was polishing

Yukon_Bumper1.jpg


I got the idea for a smaller "Surgical Buffing" implement from Mike Phillips posts and some other AGO Forum Members who suggested that the rotary backing plate combo would work.


I think it may be a combination of things that contributed to the downfall of the backing plate:

-Too much speed, 6

-Too small of an interface between the backing plate and the pad

-Thin Meguiar's Microfiber Pad may have allowed the allowed the moisture from the M105 to come into contact with the backing plate. Although the back of the pad did not feel wet.


I was working the area for only a few minutes, so I thought I was OK.

I am going to try a different backing plate, if that doesn't work, I will just go back to my 4" CCS pads.
 
allenk4 said:
I think it may be a combination of things that contributed to the downfall of the backing plate:

-Too much speed, 6

-Too small of an interface between the backing plate and the pad

-Thin Meguiar's Microfiber Pad may have allowed the allowed the moisture from the M105 to come into contact with the backing plate. Although the back of the pad did not feel wet.


I was working the area for only a few minutes, so I thought I was OK.
Click to expand...

+1 to all of the above.

What degree of correction did you achieve before failure?
 
I didn't achieve much correction at all.

I have to determine how to completely remove the textured black plastic guard on the horizontal surface to do a decent job.

The piece is attached at the top with tabs that slide in and out easily. At the bottom/front of the piece only the outer two tabs are easily accessible. I am starting to wonder if the piece is assembled before the bumper is attached to the vehicle.

It's such a small section that you really can't see unless the hatch is up....but, I know it's there.
 
I'm blaming that BP, I use a Meguiar's 3" Rotary BP and have never had this problem. And I've grounded the heck out of it.
 
You must log in or register to reply here.
Back
Top