Backing plate for sanding with the 7424

[goathead]

For those of you sanding with a 7424, what are you using for a backing plate? I'm assuming that your using the regular adhesive 6" Discs? Any info is appreciated! Thanks.

[qaz393]

meguiars back plate plus interface pad plus sanding disks

[C. Charles Hahn]

Meguiar's 6" Unigrit System (shown here with 1500 grit sanding discs):

[goathead]

Thanks, I'm looking for something a little more versatile so I could have more paper choices. I'm not looking for finishing discs actually. I've got the sand and prep the bed of my truck so I need to run 400 grit so I was hoping for like a plain smooth rubber backing plate.

[C. Charles Hahn]

Thanks, I'm looking for something a little more versatile so I could have more paper choices. I'm not looking for finishing discs actually. I've got the sand and prep the bed of my truck so I need to run 400 grit so I was hoping for like a plain smooth rubber backing plate.

Head up to Home Depot or Lowe's, then... they should have what you need.

[goathead]

Yeah, I checked HD and they didn't have any backing plates...of course it's possibly the lamest HD I've ever been to. I'll check Sears too, just didn't know if anyone used it for other than finish/damp sanding.

[gewb]

Porter Cable has a "wood worker" version of the 7424 (which came out decades before the one you have). The backing plate should be interchangable.

HOWEVER - pay attention here - you also need to get and change out the counter balance as the one for sanding is smaller (less weight) than the one for polishing vehicles.

Regards,
GEWB

[Mike Phillips]

In my article list under Wetsanding - Colorsanding - Dampsanding there's a number of articles on this topic, here's one...

Meguiar's 6" Unigrit Sanding and Finishing Discs

Meguiar's new Unigrit Sanding Discs are specifically designed for damp-sanding and can be used with a 5/16" orbit sander. These Unigrit discs offer uniform particle size and placement over the face of the disc and are available in both 3" and 6" sizes.

Meguiar's 6" Unigrit Sanding and Foam Finishing Discs



Meguiars Unigrit™ 1500 6 Inch Sanding Discs - #S61500

Product Attributes

• Precise, uniform grit particles for a smooth and even sanding pattern
• Ideal for removal of dirt, orange peel and severe paint defects on fresh finishes
• Sanding = No foam backing
• Quickly levels texture
• Micro hook & loop interface

Meguiars Unigrit™ 1500 6 inch Finishing Discs - #S6F1500

Product Attributes

• Precise, uniform grit particles for a smooth and even sanding pattern that buffs out in seconds
• Finishing = specialized foam backing
• Quickly refines sanding marks & removes moderate surface defects
• Soft foam backed disc for texture matching and scratch refinement
• Always used damp – water only
• No sanding lube
• Micro hook & loop interface

Meguiars Unigrit™ 3000 6 Inch Finishing Discs #S6F3000

Product Attributes

• Precise, uniform grit particles for a smooth and even sanding pattern that buffs out in seconds
• Finishing = specialized foam backing
• Quickly refines sanding marks & removes moderate surface defects
• Soft foam backed disc for texture matching and scratch refinement
• Always used damp – water only
• No sanding lube
• Micro hook & loop interface

Meguiar's 6" Sanding Backing Plate - #S6BP

Back side



Working face side




Product Attributes

• Distributes pressure for smoother sanding/finishing
• Precisely tuned outer edge for ideal disc contouring over flat and curved surfaces
• Allows quick disc changes with micro hook & loop interface
• 5/16 thread for use with air or electric DA’s

Meguiar's 6" Foam Interface Pad - #S6FI

Back side



Working face side


Approximately 1/2" thick





Product Attributes

• Safely follows contours and works closer to most edges
• Ideally engineered for use with Unigrit Sanding & Finishing Discs
• Allows quick disc changes with micro hook & loop interface
• For use with air or electric DA’s
• Results in one grade shift upward in finish results

Intended Markets

Sanding Discs vs Finishing Discs

Sanding Discs --> Body shops
S61500 -> S6F3000 --> Machine Compounding

The S61500 6 inch Unigrit 1500 Sanding Discs are primarily for leveling surface texture like Orange Peel or for removing heavy surface defects like dirt in paint on fresh paint. Removes material quickly but with good control leaving behind a sanding mark pattern that is quickly and easily refined to a higher level using the S6F3000 Finishing Disc. #3000 Finishing marks are then removed using a rotary buffer.


Finishing Discs --> Detail Industry
S6F1500 --> S6F3000 --> Machine Compounding

The S6F1500 and S6F3000 6 inch Unigrit Finishing Discs are more targeted at for use by Professional Detailers to remove moderate to fine defects. These foam backed discs removes material quickly but with excellent control over the depth of the sanding mark left behind. The S6F1500 sanding marks are easily refined to a higher level or removed with a rotary buffer. The S6F3000 are easily removed with a rotary buffer and a cutting compound.


Air-Powered DA Sanders
These discs can be used with Air-powered DA Sanders like the 3M Orbital Sander.

3M Orbital Sander or D.A. Sander





Meguiar's G110v2
The also fit the Meguiar's G110v2 but note there are no electric sanders approved for working around water.

The backing plate attaches to the Free Floating Spindle Assembly





If you choose to use the interface pad, the "M" logo attaches to the face of the backing plate. The "M" side of the Interface pad has the "loop" material while the face of the backing plate has the "hook" material.



The loop backing on the back of the sanding disc attaches to the hooks on the face of either the interface pad or the backing plate.









The 6" sanding discs can also be used by hand using the Meguiar's Hand Pad - S-6HP

[Mike Phillips]

This article is rather in-depth, portions are from the Power Point Presentation I use our Advanced Wetsanding Class and also the class I taught at the Mobile Detailing Expo.


Damp-Sanding Tools, Tips and Techniques by Mike Phillips



A few more for lurkers that read these threads...


RIDS and Feathersanding - A Highly Specialized Technique by Mike Phillips

Wet-sanding - Fresh Paint vs Factory Paint

Basic Hand Sanding Techniques

The Rule of Thumb

Fight or Flight Method for Gaging Surface Temperature

New - Two Schools of Thought when Hand Sanding - Straight-lines or Crosshatch Pattern

The difference between 3M's Hookit and Hookit II Hook-N-Loop Interface Systems

List of Sanding Discs at Autogeek.net

If it has paint... it gets polished...

Removing Orange Peel & Sanding Marks with the Griot's ROP and the Wolfgang Twins

How long will a half sheet of wet/dry sandpaper last before it stops cutting and you need to replace it?

Can an air-powered DA Sander be used to polish paint?

[Mike Phillips]

HOWEVER - pay attention here - you also need to get and change out the counter balance as the one for sanding is smaller (less weight) than the one for polishing vehicles.

Regards,
GEWB

Gary's right, at least that's the original idea behind the different weights of couterweights... for what it's worth, I've never checked or changed a counterweight on a tool before using it to dampsand or machine compound, polish or wax paint.

Neither the Meguiar's or the Griot's DA Polishers have the ability to modify counterweights and we use these in all our Wetsanding Classes to dampsand.


I'm not saying my way is the right way or the best way just saying all the sanding, cutting, polishing and waxing seems to get done with any of these tools and with whatever counterweight is on the PC that's closest to my hand when I reach for one.

The origins of the Porter Cable are documented in this thread...


The Free Floating Spindle Bearing Assembly - The Story Behind The Story...