Air powered orbital sanders?

[William Hodge]

I used a Dynabrade sander a lot. I have also used electric random orbital sander a lot. The Dynabrade required 15 cfm. The 5 hp 3 phase compressor would heat up, because it only would put out 17 cfm, and any other use in the shop would be more than the compressor could handle. The maintenance of a compressor to run a sander was not worth it.

More important, my Dewalt 5" random orbital sander has better dust collection when hooked to a central vac. I have a central vac in the shop, meaning the vacuum is out side the back door, and it's quiet.

Unfortunately, the electric sanders are disposable, not repairable.

[Alex Zeller]

In the past I used air sanders all the time (for bodywork). One of the things not talked about here is that the air coming out of the sander will blow dust everywhere. While my electric palm sander is bulkier it's easy to connect to the dust collector. I haven't looked at what's on the market now but I would make sure that it has some sort of dust collection capability.

[Robert Engel]

The problem with air-powered sanders is that they require oiling (preferably inline) and there's always an issue of residual oil spitting on the wood, which is bad mojo re finish contamination. I would never dream of using them for woodworking. This is not something you should be thinking about.

I've never had an issue and I know a lot of commercial ww'ing shops use them. If they spat oil, then body shops wouldn't use them either.

+1 on what Dave said. I use a 3M sander and very happy. Also like the Cubitron sanding disks a lot. Seem to last forever!

Biggest advantage I see is 1) they sand faster and 2)better dust collection. Yes you need a big boy compressor to handle the cfm.

[Van Huskey]

Unfortunately, the electric sanders are disposable, not repairable.

Cheap ones are, the quality ones like Mirka and Festool are repairable.

[Van Huskey]

2)better dust collection.

Which air sanders are you comparing to electric sanders?

[Kevin Jenness]

"you need oil _in_the_tool_. It doesn't matter how it got there upstream. I do a lot of automotive work, and I have an elaborate system for super clean/dry air, for painting, finishing, etc. But the tool needs the oil. If it doesn't get it, that tool is gonna die. Inline oilers (or the equivalent) are the way and the truth. And that's the point of contact with a sander and the wood, and there's no way around that."

I worked in a shop with 5 or 6 Dynabrade sanders for 14 years. One was there when I started and was still going strong when I left. I don't remember any of them dying in service. All those tools got two drops of oil a day, if that, no inline oiler and no oil contamination on the work. Believe me, our finisher had no qualms about pointing out sanding problems.

That said, I am happy with my Festool EC-125. I don't care to invest in a big compressor and drier and run a 5hp motor to power a sander that only needs a few amps at 110 volts. The dust pickup is better with the Festool, but not a quantum leap (our air sanders were teamed up with Fein vacs). If my budget had been less squeaky I would have gone for a Mirka, they are a very good competitor to an air sander and my old shop has a couple of them now. Still, I doubt the electric units will outlast those Dynabrades.

[Albert Lee]

I have a Festool LEX3. you need a big compressor with a matching airtank if you want to use an air sander... a 7.5hp at least but depends on your usage. when I use my air sander my compressor can happily keep up with the air use. it uses about 300l/min, which is about 10cfm. you need a compressor at least 20cfm (50% duty cycle) if you have a rotary screw compressor then its a different story...

[Warren Lake]

also depends what you are sanding, heavier work usually done first on my stroke sander before the dynabrade

[Matt Day]

Thanks for all the input guys. Looks like we’re talking a $1500-$2000 compressor for a decent 5hp compressor. Sound about right? I love buying used machinery my gut tells me to buy new, for fear of an unmaintained machine or rusted tank. .

[Cary Falk]

Put me in the camp that doesn't understand the appeal of air sanders in a wood shop.
Huge noisy compressor
bulky air hose
noisy sander
expensive air/oil separators

[David Kumm]

Most 1500-2000 compressors of that size run a fairly fast pump- usually from China. The best 5-7 hp compressors under 2500 are used. A Quincy QR 325 or 340 is my first choice. They ran slow and quiet in comparison to most new. They had the best valves and are easy to rebuild. Quincy sells gasket kits and there are videos on youtube showing how to rehab. Throw the valves into some Evaporust ( or a die grinder and while wheel )and with some sandpaper and gaskets you can have a compressor that would cost well over 5K new and still run for the rest of your life. Saylor Beall, Kellogg, and certain Ingersol Rand were good too but not equal to the Quincy. If you need a big compressor and have average rehab skills, the Quincy is an easy way to a great compressor. I have 1000-1200 in a 5 hp 120 gal tank and 2500 in a 25 hp unit that will handle any sand blaster. I bought a rehabbed Kellogg for 750 delivered some years ago. Good stuff is out there. Dave

[Martin Wasner]

Still, I doubt the electric units will outlast those Dynabrades.

They don't.

But. Even replacing a $600 sander once a year, it's still cheaper. If my compressor runs 2080 hours a year, and for what I'm paying for electricity, it would cost me $3700 a year. Plus wear and tear on a $8,000 compressor with a life expectancy of 20k-30k hours.

I like the Dynabrade sanders, but with the same abrasive the Mirka cuts faster and leaves a better scratch.

For a hobbyist, it's not really going to add up, but commercially it's real money at the end of the year.

The Dynabrade is a sweet unit we still use them frequently, but the bulk of our sanding happens with a brushless Mirka. It's cheaper and I feel more productive. I also think the vibration is better with the Mirka.

[Albert Lee]

Thanks for all the input guys. Looks like we’re talking a $1500-$2000 compressor for a decent 5hp compressor. Sound about right? I love buying used machinery my gut tells me to buy new, for fear of an unmaintained machine or rusted tank. .

I highly recommend silenced piston compressor, its quiet and low maintenance, say the likes of Chicago Pneumatics CPRS series, I have one of these and it has been great.

to give you an idea how loud/quiet it is, here is the video I took

https://youtu.be/xMpRpo6GmJ8

my previous compressor was a hydrovane... and yes for Compressor it is better to buy new.

[johnny means]

I've got 15 year old Festool electric sanders that look like they were used as hammers, still going strong. Twenty years in commercial shops using air sanders, I've never seen the oil problem.

[Van Huskey]

I've got 15 year old Festool electric sanders that look like they were used as hammers, still going strong.

And those are brushed, the life expectancy of a brushless sander is much longer.

Obviously, if they are being run in production 8 hours a day no electric will last 15 years one just has to work out the real cost of using air vs electrical, for the hobbyist like me energy costs aren't a big factor and it may give me a good excuse to buy a big compressor but I still prefer brushless electric.