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slipchuck
09-20-2006, 12:09 PM
Hi again :D

I was wondering if someone can explain to me the differences in the two.
as my air compressor is not big enough for a dual action, is an electric random orbit almost as good?


thanks

randy

Henry
09-20-2006, 12:48 PM
Hi again :D

I was wondering if someone can explain to me the differences in the two.
as my air compressor is not big enough for a dual action, is an electric random orbit almost as good?


thanks

randy
Depends on what you are doing. Also, what kind of DA are you trying to run off of and what is your air compressor.
Some DA's are VERY air hungry like the Ingersol Rand while my fleet of Hutchins are extremely stingy on air requirements.
If you are sanding and depending what you are sanding air would be the preferred method so try to go with that. Henry

slipchuck
09-20-2006, 03:57 PM
Depends on what you are doing. Also, what kind of DA are you trying to run off of and what is your air compressor.
Some DA's are VERY air hungry like the Ingersol Rand while my fleet of Hutchins are extremely stingy on air requirements.
If you are sanding and depending what you are sanding air would be the preferred method so try to go with that. Henry

HI

I have a powerfist 4 gallon 2hp peak pancake that produces 5.2 cfm @ 40 or 50 psi (can't remember which one)
and 4.2 cfm @ 90 psi

some of my air tools run great that are rated for 4 cfm @90 like my air hammer, my air sander (the type that just spins fast) that is rated for 4.5 cfm @ 90 doesn't run that well at all.

thanks

Henry
09-20-2006, 10:38 PM
HI

I have a powerfist 4 gallon 2hp peak pancake that produces 5.2 cfm @ 40 or 50 psi (can't remember which one)
and 4.2 cfm @ 90 psi

some of my air tools run great that are rated for 4 cfm @90 like my air hammer, my air sander (the type that just spins fast) that is rated for 4.5 cfm @ 90 doesn't run that well at all.

thanks
First off is my family and I extend heartfelt good thoughts and prayers to Nicholas.............

Second is I hate to tell you but that compressor is just too small. You could get by with even a small 5HP 20-25 gallon tank 220v air compressor. My advice would be to shop for a used compressor so you'll have it as it is the heart of the trade IF you intend to go further down this path. What are your intentions in this hobby. Henry

CDJr
09-20-2006, 11:35 PM
Ya, 4 cfm isnt really big enough for much, especially a DA sander. Most Ive seen were VERY air-hungry. As far as an electric, itd probably do most things an air one would do, itd just take longer and be more trouble. Ive used my electric sanders a few times and they got the job done. You can find a good deal on a suitable compressor if you look around hard enough cuz thats what it sounds like you need before you buy any more air tools. Hope this helps :)

Robert
09-21-2006, 08:56 AM
Slip,

Getting back to your first question. Dual action and random orbit are used interchangeably so, you have to ask the person using the terms what they mean.

As far as I'm concerned those machines where the shaft spins freely while traveling in an orbit should be called random orbitals - since the pad rotates in a random way. The other machines, where the shaft travels in an orbit but is gear driven so that it's always spinning too should be called dual action.

The Makita BO6040 is a dual mode machine that does both.

As far as air usage is concerned, a true dual action machine like the Chicago Pneumatic 9900 eats air like you can't believe, if you don't have a really serious air compressor forget it. The random orbitals like the AirVantage sanders are much easier on your compressor.

Dennis Schmidt knows more about electric sanders than anyone needs to know so if you have a question about those post a question directly to him.

Robert

drizler
09-24-2006, 01:41 PM
So why is is that when my IR DA sander is in the da mode it runs on forever hunkey dorey. When I set it to straight circular mode whatever you call that it eats air like no tomorrow and has about as much power as the cheapest Harbor Freight junker there is. Should the IH have power in straightline mode? I could just about stop it between my fingers if I had gloves on yet it cuts really fast. I always wondered about that one.

Phil V
09-24-2006, 04:41 PM
Drizzler, The reason your IR DA (or ANY DA for that matter) is set in the locked spindle rotary mode they will have very little power. Most DA's air motors are rated at 10,000 rpm. When you lock that spindle it then that DA is trying to get the pad to spin 10,000 rpm bypassing the friction of the sanding pad against the surface you're sanding. When the spindle/pad is in the unlocked position there is very little friction to overcome as there is a bearing between the spindle and the pad. The ONLY time a DA should be in the locked position is when its being used as a grinder (stripping paint mostly).


Now back to slipchucks original question - difference between a dual action sander and an orbital sander ?

A DUAL ACTION sand IS an oribital sander.

Back to the basics -- A dual action (DA) sander is called "dual action" because it can be run in two separate and distinct modes. One mode is orbital (when the air motor spindle is locked to the sanding pad). The other mode is RANDOM orbital (the air motor spindle has a bearing in it that the sanding pad is attached to. So the sanding pad not only turns orbital along with the spindle but it turns in a random oribtal because of the bearing).

The AirVantage/Dynabrade type air sanders are random oribial while the sanders like the National Detroit DAQ is a true Dual Action sander (technically a random oribtial as well as an eliptical orbital).

THEN we have the air sanders like the Natrional Detroit 8" DA 900 which are referred to a GEARED ORBITAL. The air motor runs at 10,000 rpm but the 8" pad run in the 1,000 rpm range because the pad is geared down from the air motor.

To a novice look at it this way - if you want more aggressive material removal then us a regular DA. If your plan is to do finish sanding of old paint, primer or new clearcoat then use a random orbital commonly referred to as a palm oribital sander (like the airvantage and dynabrade sanders)

There - you just learned more about autobody/paint shop sanders than you ever really wanted to know, hehehe.

Robert
09-24-2006, 06:34 PM
Phil,

Don't you think they should call that "dual mode" instead of "dual action" or maybe we should come up with another term all together for forced rotation on an ellipse.

Robert

drizler
09-25-2006, 12:55 PM
I now feel like I be tutallly edumacated. Now how do dem motors get that space shuttle to the moon anyways......................Must be hot air from all those politicans:p

slipchuck
09-26-2006, 01:30 PM
I just bought an 5" hook and loop 4 amp random orbit sander and am amazed how fast it takes down material. not much for tight spaces, but great for big flat surfaces.
If I had this when I started, man would I have finished sooner :)

glad I went with a 4 amp one

randy