What causes the buffer to hop?

[sellncars]

I purchased a few 8" Meguiars foam pads which I'm new to. I have been using the Rotary buffer for at least 10 years now with a ool pad. Until recently i wanted to try the foam to see if there was a difference. I put on the same product as well as the same amount and get a nasty hop to the buffer. What is the cause of this? Any help will be much appreciated.

Thank you,
Sellncars

[sellncars]

What causes pad hop on a rotary buffer?

I purchased a few 8" Meguiars foam pads w7000 and w9000 which I'm new to. I have been using the Rotary buffer for at least 10 years now with a wool pad. Until recently i wanted to try the foam to see if there was a difference. I put on the same product as well as the same amount and get a nasty hop to the buffer. What is the cause of this? Any help will be much appreciated.

Thank you,
Sellncars

[probegt]

I noticed this with 8" pads also and switched to the smaller pads and it seemed to calm it down a little. Are you priming your pads before use? Maybe you arent using enough product or the pad(s) are gummed up. Their are lots of scenerios that may have caused this.

[Mike Phillips]

Re: What causes the buffer to hop?

Originally posted by sellncars
I purchased a few 8" Meguiar's foam pads which I'm new to. I have been using the Rotary buffer for at least 10 years now with a wool pad. Until recently i wanted to try the foam to see if there was a difference. I put on the same product as well as the same amount and get a nasty hop to the buffer. What is the cause of this? Any help will be much appreciated.

Thank you,
Sellncars

Unlike a wool pad, when used correctly, a foam pad is held flat against the surface which results in a dramatic increase in contact area.

Like probegt mentioned above, when making the switch from wool pads to foam pads the smaller 6" foam pads are easier to use. As for rotary hop, there are a lot of factors that can cause this.

First off, what chemical are you using with the foam pad? Here's a thread you might want to check out...

Product, Pad and Speed settings for the Rotary Buffer

Mike

[sellncars]

Hi,
The pads are brand new. Yes, i did prime the pads first. The product that i have and have been using for years is ultra cutting creme made by Presta products. I also have DACP which i only use with my PC with Meguiar's pads. No hop there. I keep the pads as flat as i can either way.

Thank you,
Ed Fitzsimmons Jr.

[Boss_429]

Yep, a lot of good information in this link, and the one Mike pointed out. I'll add another hint........... when using foam pads, make sure that the pad is as centered as possible on the backing plate. With wool pads, this was never a problem. Like Mike said, there are can be many causes of rotary hop.............. too much product, not enough product, speed of rotary set too high, speed of rotary set too low, product and pad combination, dirty/gummy pads, angle of pad on the surface............... Etc.

[Kevin Brown]

A very SHORT explanation...

I know what you're going through. Anyone that's using foam pads has encountered the same 'hopping' problem, so don't worry. If you've been buffing for 10 years, you'll get the hang of it in no time. Let's go over the dynamics of pads.

Wool pads are very forgiving and easy to control in comparison to foam pads. Wool pads glide as they change shape. The wool strings lay upon each other as the pad spins. Since the strings are individually thin, they easily change overall pad thickness (as varied pressure is applied and buffer angle is changed). In other words, they conform to flat or curved surfaces rather easily.

A few reasons why foam pads hop:

1. Foam pads are squishy, and have a natural tendency to rebound.
All those tiny air pockets purposely designed into the pad allow compression and rebound (If you squeeze the pad between your fingers, it'll try to return to its natural shape).

When the pad is placed on the paint surface and the buffer is throttled, the foam pad twists against the paint initially. Once it planes, it returns to its natural shape (close to it, anyway). The amount of pressure you are applying to the buffer also determines the amount of distortion the pad will encounter. Push hard, and the pad flattens. Of course, it wants to rebound to its natural shape.

Therefore, a foam pad needs something to control its rebound (Just as a car needs shock absorbers to control suspension springs). Effectively, YOU become the shock absorber. You must learn the amount of pressure needed to keep the pad shape consistent. If bouncing does occur, you'll have to lift up on the buffer (to reduce pressure momentarily), or change the angle of attack.

On that topic: Assuming that downforce remains the same, if you change the angle of the pad to a more aggressive one, the pounds per square inch applied to the paint will be increased because less pad is touching paint, but the same force is being applied, right?

I hope I've explained this properly. If I did, you can easily understand why compression and rebound would cause foam pad hop.

2. Too much buffing polish applied to the surface.
Whereas a wool pad easily cuts through excess buffing polish (a weedwhacker effect takes place), a foam pad does not easily cut through excess polish. Foam pads work well because they are made to glide along the surface rather than cut into it. If too much polish is applied, the pad cannot cut through, and instead rides upon it.

The excess polish either gums up on the paint, or saturates the pad. When this happens, the foam pad does not glide along smoothly- It grips and then releases (at 1500 r.p.m. this can happen many times per second). Severe compression and rebound occurs, and VOILA! - Your buddy pad bounce stops by for a quick visit.

3. Not enough polish applied to the painted surface.
If not enough polish is applied to the paint, the foam pad does not glide. Instead, the rubbing action creates heat (which in turn causes the pad to 'hook up' (like a drag slick!). If this is a common problem for you, I feel sorry for the state of your wallet... Repainting will definitely be in your future.

4. Foam Pad Saturation.
When too much product is repeatedly applied, eventually the polishing oils and/or solvents will enter the foam pad and saturate it. When this happens, the integrity of the pad is compromised.

The foam material may become 'soft' and non-pliable (it won't keep it's original shape). It'll become gummy.

As a rule, you should carry two to three times more foam pads on hand as compared to wool pads. Rotating your pads through the buffing process will allow them to air dry, evaporate solvents, and minimize thermal breakdown.

It is very important to keep polish build-up to a minimum on the pad itself. Use a soft brush designed for foam pad cleaning to remove residue, and if you must wash a foam pad, use only car wash solution or baby shampoo, as they are typically pH balanced (and won't attack the glue holding the velcro on the pad). To dry, roll the pad into a terry cloth towel and squeeze. Allow to air-dry.

[Boss_429]

Great post!

[Jeff Burrows]

Nice Post!

I think the same as the previous posts. I also think you should let the buffer do its work and not force it to rapidly across the surface. I like to set the buffer at 1,100-1,200 RPMS and let it work the surface longer and by not letting it go to fast across the surface it doesn't hop. Also try to experiment on some old panels from a junk yard and get a better fell for the pads.
Best of luck! Jeff Burrows

[Tim Lingor]

Hey,

Great post Kevin!!

Just to add....

Before buffing with the rotary, make sure the surface is totally clean of any clay residue etc... After claying, I tend to go around the vehicle with some #34 Final Inspection just to make sure no residue was left behind. If there is, the pad will grab it, and proceed to bounce.

And as mentioned in Kevin's post...keep switching pads when one becomes saturated.

Cheers!

Tim

[Kevin Brown]

2hotford and Boss_429 -

Thanks for the compliments. I hope that the explanations will be easy to understand for the beginners among us. Sometimes when we've been doing something for so long, we tend to forget to teach the basics.
It's easy to overlook explanations, while stating only facts.

Stating only the facts makes you a know-it-all.

Explaining things gets you closer to being a teacher.

[Mike Phillips]

Nice post Kevin!



Mike

[sellncars]

Re: A very SHORT explanation...

Originally posted by iamwaxman
I know what you're going through. Anyone that's using foam pads has encountered the same 'hopping' problem, so don't worry. If you've been buffing for 10 years, you'll get the hang of it in no time. Let's go over the dynamics of pads.

Wool pads are very forgiving and easy to control in comparison to foam pads. Wool pads glide as they change shape. The wool strings lay upon each other as the pad spins. Since the strings are individually thin, they easily change overall pad thickness (as varied pressure is applied and buffer angle is changed). In other words, they conform to flat or curved surfaces rather easily.

A few reasons why foam pads hop:

1. Foam pads are squishy, and have a natural tendency to rebound.
All those tiny air pockets purposely designed into the pad allow compression and rebound (If you squeeze the pad between your fingers, it'll try to return to its natural shape).

When the pad is placed on the paint surface and the buffer is throttled, the foam pad twists against the paint initially. Once it planes, it returns to its natural shape (close to it, anyway). The amount of pressure you are applying to the buffer also determines the amount of distortion the pad will encounter. Push hard, and the pad flattens. Of course, it wants to rebound to its natural shape.

Therefore, a foam pad needs something to control its rebound (Just as a car needs shock absorbers to control suspension springs). Effectively, YOU become the shock absorber. You must learn the amount of pressure needed to keep the pad shape consistent. If bouncing does occur, you'll have to lift up on the buffer (to reduce pressure momentarily), or change the angle of attack.

On that topic: Assuming that downforce remains the same, if you change the angle of the pad to a more aggressive one, the pounds per square inch applied to the paint will be increased because less pad is touching paint, but the same force is being applied, right?

I hope I've explained this properly. If I did, you can easily understand why compression and rebound would cause foam pad hop.

2. Too much buffing polish applied to the surface.
Whereas a wool pad easily cuts through excess buffing polish (a weedwhacker effect takes place), a foam pad does not easily cut through excess polish. Foam pads work well because they are made to glide along the surface rather than cut into it. If too much polish is applied, the pad cannot cut through, and instead rides upon it.

The excess polish either gums up on the paint, or saturates the pad. When this happens, the foam pad does not glide along smoothly- It grips and then releases (at 1500 r.p.m. this can happen many times per second). Severe compression and rebound occurs, and VOILA! - Your buddy pad bounce stops by for a quick visit.

3. Not enough polish applied to the painted surface.
If not enough polish is applied to the paint, the foam pad does not glide. Instead, the rubbing action creates heat (which in turn causes the pad to 'hook up' (like a drag slick!). If this is a common problem for you, I feel sorry for the state of your wallet... Repainting will definitely be in your future.

4. Foam Pad Saturation.
When too much product is repeatedly applied, eventually the polishing oils and/or solvents will enter the foam pad and saturate it. When this happens, the integrity of the pad is compromised.

The foam material may become 'soft' and non-pliable (it won't keep it's original shape). It'll become gummy.

As a rule, you should carry two to three times more foam pads on hand as compared to wool pads. Rotating your pads through the buffing process will allow them to air dry, evaporate solvents, and minimize thermal breakdown.

It is very important to keep polish build-up to a minimum on the pad itself. Use a soft brush designed for foam pad cleaning to remove residue, and if you must wash a foam pad, use only car wash solution or baby shampoo, as they are typically pH balanced (and won't attack the glue holding the velcro on the pad). To dry, roll the pad into a terry cloth towel and squeeze. Allow to air-dry.

I thank you very much, this was well explained. If the snow here ever stops i will get a chance to try some new things. Honestly thinking now, i dont think i had enough product on the pad. Time will tell. I will let everyone know if this works.
Thanks again,
Ed Fitzsimmons

[papi_Jay]

If anyone still has a real problem with buffer hopping , you can alleviate it somewhat by using one of the padded backing plates .
They are not just urethane , but have a rubber like material sandwiched between the top spindle area and hook n' loop plate