Dynabrade random orbital polisher kit

[Kevin Brown]

...I just ordered this kit from Dynabrade that converts your rotary polisher into a random orbital polisher with the push of a button....

From your link and pics, it looks like you ordered the random orbital conversion, part #61374.

Dynabrade also offers a Dual Action Buffing Head.

It allows you to switch between random orbital or forced rotation orbital with the push of a button, part # 61379 or #61384

Not saying you ordered the wrong or right one... just making sure you know that only one lets you push a button to convert the action.

[tuscarora dave]

From your link and pics, it looks like you ordered the random orbital conversion, part #61374.

Dynabrade also offers a Dual Action Buffing Head.

It allows you to switch between random orbital or forced rotation orbital with the push of a button, part # 61379 or #61384

Not saying you ordered the wrong or right one... just making sure you know that only one lets you push a button to convert the action.

AAAAWWW MAAAAHHN!!!I wanted the one with the button!!! I can't believe that the one with the button costs less. Dang!! Well maybe this one is better because it costs more.

[Kevin Brown]

AAAAWWW MAAAAHHN!!!I wanted the one with the button!!! I can't believe that the one with the button costs less. Dang!! Well maybe this one is better because it costs more.

I can't believe how CHEAP they're selling these attachments. They are up to 60% LESS than everybody else! Good prices, or somebody punched in cost (a discounted cost at that) and forgot to mark their numbers up. That happened to me once, and I got a lot of my SK/Facom tools at a beyond great deal.

Or, they may have simply got a "clean out our warehouse for us and we'll cut you a deal" price from Dynabrade.

Both units are a steal at that price.

[Custom Detail]

Here the link man that is cheap!!!!!

LINK REMOVED

[2old2change]

Kevin
Which is the more desireable unit to have ? 61374 ,61379 or 61384.

[C. Charles Hahn]

Kevin
Which is the more desireable unit to have ? 61374 ,61379 or 61384.

Good question! I'm guessing the 61384 is the better unit since it switches between two modes, but Kevin may disagree. For the price, I might just pick one of these up to have around.

[Joe@Superior Shine]

I paid $145 for the "push button" model a little over a year ago!!!

[Kevin Brown]

You really can't go wrong with either one, but for sure if you can get the switchable one, GET IT!

Here's the part number breakdown:

61374 Random Orbital Buffing Head (5/8"-11 female thread)

61375 Random Orbital Buffing Head (M14x2 female thread)

61379 Dual Action Buffing Head- Switchable

61384 Dual Action Buffing Head with Wool Pad and 7" Backing Plate (5/8"-11 female thread)

61385 Dual Action Buffing Head with Wool Pad and 7" Backing Plate (M14x2 female thread)

[Kevin Brown]

BY THE WAY... NONE OF THESE ATTACHMENTS CREATE A TRUE ROTARY ACTION.
The motion is always offset. That being said... they are still killer attachments!

These babies feature a 3/4" diameter orbit. That, my friends, is 2.5 times the stroke diameter of the Porter Cable 7424XP, the Griots 10765, and the Meguiar's G110v2. So what, you say? For an accurate comparison, let's use the G110v2, as Meguiar's lists its speed settings specifically:

1=1800 OPM / 2=2800 OPM / 3=3800 OPM / 4=4800 OPM / 5=5800 OPM / 6=6800 OPM

Let us assume that you want to run either machine at full speed in hopes of maximizing cutting or leveling power (it doesn't always work that way, but most times it does). It seems as though the Dynabrade attachment in forced rotation mode is the weakling among the two- and it is, if we are comparing how many times the backing plate would orbit around the driveshaft spindle.

If your goal is to repetitively rub a buffing pad across a patch of paint, the G110v2 will be superior. But, what is your purpose? Fine polishing of the area, or rapid removal of paint? If you are hoping to super-polish a surface so that it is visually glossier, you shouldn't be running the machine at full gait anyway. Look at this diagram to better understand why:



Lower the orbits per minute (OPM) but increase the pad speed at the edge, and you'll get a smoother polishing transition curve, yet gain cutting or leveling power. Pretty interesting.

So, let's be more realistic with our speed setting, and set the speed dial somewhere in the middle, perhaps an even 4,800 OPM, (which is speed setting 4 on the G110v2).

The G110v2 still delivers more repetetive rubbing of the paint than the Dynabrade, but when we compare the speed in which the outer edge of the backing plate is moving... it's a different story. Recall that the Dynabrade's stroke diameter is 2.5 times that of the G110v2. In order to equal the speed in which a point on the backing would be moving on the smaller machine, we would only need to set the rotary to 1,920 RPM to equal the 4,800 RPM delivered by the G110v2. Bump the speed dial all the way to 3,000 RPM on the rotary, and you've got an equivalent speed of 7,500 OPM with the smaller machines, which is a number they do not achieve. Speed increases force, and force keeps things moving when resistance is encountered. Ta-da! We've got serious cutting power, baby.

If you opt for the Dual Action Buffing Head and run it in locked mode, your machine will deliver a 1:1 ratio of rotations to orbits. That's some massive cutting power.

Your typical rotary buffer (DeWalt DW849, Makita 9227C) can deliver up to 3,000 revolutions of the backing plate per minute and 3,000 orbits per minute. My best guess puts a loosely set-up random orbital at a maximum of 12 turns per second using the maximum speed setting, or 720 RPM and 6,800 OPM. That's using a 5.5" D/A Microfiber Disc or a Surbuf pad (good luck getting that level of speed with a foam pad).

All in all, the Dynabrade attachment is likely the most under-used yet ultra-capable machine on the market. It looks heavy, though, so most guys thinks it's going to feel bulky. Sure, it's bigger, but even though you'll be using a larger and heavier machine, the leverage is better, and high speed vibration is greatly diminished compared to the smaller and lighter machines, especially if you tend to run 'em wide open all the time.

[Kevin Brown]

Here is an old thread about the Dynabrade 61379/61384:


My friend Mike bought the Dynabrade Dual-Action Buffing Head:







The aluminum housing measures 4-3/4” in diameter.





With the backing plate removed, the innards are easy to see.





When the power slide button is engaged, this latching pin is raised.
This locks the entire housing to the drive, and the backing plate is forced to rotate.



When the power slide pin is disengaged, the latching pin is lowered.
The aluminum housing is able to rotate freely. This is set to the random-orbital mode.





We removed the backing plate to cut the size down. It uses a standard 5/16”-24 spindle.
Our plan was to remove the white foam along the outer edge.
This way, we could fit the Meguiar’s 7” pads to the backing plate.



This shot shows the overall diameters of the housing and the three plates we were going to use.



The Mirka plate will be used as the primary plate for the 7” pads.
The modified Dynabrade plate will be used as a backup.



See? the Mirka plate is nearly identical in size to the plastic part of the Dynabrade plate.



This is the Meguiar’s Soft Buff 7” Foam Cutting Pad. It is getting rave reviews.
Our goal was to allow Mike to attach the trio of foam pads to the attachment.
Mike will also be using the So1o Pad system, which wil fit nicely once we are done.



An X-acto knife and some hand sanding easily removed the unwanted foam.
Another way to cut the foam is to mount the backing plate onto a drill.
Then, carefully push the X-acto into the foam as the drill rotates the plate.



Voila! The plate fits perfectly into the recessed part of the foam cutting pad.



The Meguiar’s WWHC7 So1o Wool Heavy Cutting Pad will work well with this machine.



Here is a shot of the pad mounted to the machine. You can really see the offset!



The slide pin.



Wow, what an offset. This machine feature a 3/4” (12/16”) diameter orbit.
For comparison, the Meguiar’s G110 features a 5/16” diameter orbit.







We run the Makita at various RPM settings. It seemed to like 2,700 rpm with this 6-1/2” pad.









Keep in mind that this attachment was designed for use with larger pads than we were using, so the counterbalance was weighted accordingly.
From what I understand, Dynabrade spent a lot of time dialing in the balance for 8” and 9” pads.

If you plan on using smaller pads and plates, count on some vibration.
In terms of comfort, the optimum speed setting will be easy to find by adjusting the speed on the fly.
Thanks to the 3/4” orbit size and the power and rpm capabilty of the rotary machine, you will be hard pressed to stop the rotation of the pad in random-orbital mode (even at slower speeds). I did not remember to weight the unit... D'oh! It wasn't unusually heavy, that is certain (credit the aluminum housing for the weight savings).

This is a time saver, and if you are comfortable with a rotary machine, you will really dig this baby!