Angle grinder for tight area surface prep and maybe light polishing recommendations

[alas]

Hello All,

New member here looking for some advice.

I just picked up an old air compressor to do mostly home home automotive projects with.

It's a Campbell Hausfeld workhorse from about 6 or 7 years ago. 20 gallon tank, capable of 6.1 CFM at 90psi.

I need to do some surface prep work on an exhaust and a bit of head work and I'm looking for a prep tool or I guess a die angle grinder with 2" sanders would work fine for me. I would also like to to work easily with some polishing heads

Can anyone recommend me something that would be a good match to my air compressor?

So far I've looked at the following, but I haven't found so many reviews on the cheaper end ones.

-OEM TOOLS 25778 2
http://www.amazon.com/dp/B004FELNAI/?tag=atomicindus08-20

Looks manageable for my compressor but absolutely no reviews on this tool.

-Astro 3050
http://www.amazon.com/dp/B000FN8KUO/?tag=atomicindus08-20

Not sure if my compressor can handle this one

-Aircat 6255
http://www.amazon.com/dp/B000AYS01C/?tag=atomicindus08-20

I think this requires more power than I have.

-Any Ingersoll Rand grinder, but I haven't found one that my compressor is powerful enough for.


Any feedback is appreciated!

Thanks and best regards,
Eric



-E

 

[DHCrocks]

http://www.ingersollrandproducts.com/am-en/products/tools/surface-preparation-finishing-tools/sanders-polishers-buffers/maintenance-automotive-sanders-polishers-and-buffers/sanders/3103k

I have an IR it looks like this but not sure if its the same model since it must be about 10 years old now. it'll run fine on my compressor which is probably about the same capacity as yours. I can't run it continuously but short 2 minutes bursts are no problem, then give the compressor time to catch up. I like it the grip is really comfortable and its relatively quiet.

 

[alas]

Thanks for the advice!

So, the website says its 19 CFM, I'm assuming that's sCFM? But at what pressure?

I guess 2 minutes of working time might be ok but my old compressor is loud and doesn't fill very fast, so I think a grinder that doesn't require as much air would suit me a bit better.

What do you think?


-E

 

[Ign]

I don't see how a 20 gal compressor at 6-7 cfm is gonna run any of those.

You might look at the Milwaukee 2438 but it's much larger

 

[Astro_Pneumatic_Tools]

Get one of these and I'll hook you up with a threaded roloc holder so it can be used as a surface prep tool as well. Nothing is going to come close to this size

http://www.astrotools.com/index.php/new-products/onyx-micro-2-sander-velcro-0-4hp.html

 

[firworks]

Get one of these and I'll hook you up with a threaded roloc holder so it can be used as a surface prep tool as well. Nothing is going to come close to this size

http://www.astrotools.com/index.php/new-products/onyx-micro-2-sander-velcro-0-4hp.html

Whoah that thing is cool! I've never seen it before. Also pretty reasonable CFM requirement. If I didn't have the Milwaukee 2438 I'd strongly consider getting that one. Although... it's not Dual Action you know.

View media item 61074

 

[DHCrocks]

Thanks for the advice!

So, the website says its 19 CFM, I'm assuming that's sCFM? But at what pressure?

I guess 2 minutes of working time might be ok but my old compressor is loud and doesn't fill very fast, so I think a grinder that doesn't require as much air would suit me a bit better.

What do you think?


-E

my compressor says 5.5scfm @ 90psi. and it runs it just fine. it'll bog down at lower pressures so I typically use 90-110. when your tank is full @ 140psi you are basically just dumping the tank so it shouldn't be a problem and it'll flow what ever it takes. when the pressure drops and the compressor kicks in that's when the rating comes into play and it can't keep up. so you need to wait till it fills up again. this is really a small tool used for small things so you wouldn't usually be using it continuously anyways. I use sanding disks, and scotchbrite pads to debur, grind or polish. I use it for a minute or two then check the part as the compressor catches up and then go at it again. I don't see how this would be more demanding then any other mini grinder it's really tiny. Consider a pistol grip like this it is very comfortable to use, you can hit the items square more easily then an angled grinder so its easier on your wrist.

 

[Voi]

Subscribed. I've been meaning to start a thread like this.

 

[md21722]

You aren't going to find one that will work continuously with your air compressor. As the other posted said, you will end up using it until its down on power and then waiting for it to catch up again. The most efficient die grinders I've seen are rated 11-12 SCFM @ 90 PSI but many others use 18-24 SCFM @ 90 PSI. This is free speed so when you put pressure on it to do work they will slow down some and use less air. If you don't want to wait for your air compressor to catch up or don't want to buy a much bigger one then you need to go electric. If you want to try, go for one of those 0.4 HP that are linked.

 

[Astro_Pneumatic_Tools]

If you want to try, go for one of those 0.4 HP that are linked.

That 0.4HP is more power than most right angle die grinders and the 3050 kit linked in the first post.

You would need to buy a 1/2HP right angle die grinder or our 3057 for something with more power, both again much larger.

 

[alas]

Wow, I didn't expect this much feedback so soon. This forum is awesome!

Ok so, I want to purchase today so I can do work on the weekend.

It seems like that little Astro onyx will work fine with the mod suggested. Is there a huge benefit to having dual action?

Also, the first linked (from my post) from OEMtools is rated at 4CFM or so, doesn't that mean my compressor should be able to keep up for longer time vs. the IR suggested by DHCrooks?

Should I be wary of this brand (OEMTOOLS)? I'm just curious at this point as that Astro one looks pretty awesome.


Thanks all for your input!

-E

 

[md21722]

When it comes to rotary tools, CFM numbers less than 10 are "average CFM" which means "average run time of 15 seconds over 60 seconds". To get the true air usage you need to multiply that number by 4. So one that says 4 will use less air than one that uses 6, but both will use more air than your compressor can make. OEM TOOLS generally work OK but there is nothing to get excited about with them. Air tools can be loud and the better ones are usually significantly quieter.

 

[Astro_Pneumatic_Tools]

Ok so, I want to purchase today so I can do work on the weekend.

Weekend as in tomorrow?

Let me know during business hours if you get the ONYX and I'll send you the 320RH2 and 320RH3 so you can use it as a surface prep tool, otherwise you need velcro backed sanding paper to use it out of the box.

And no you don't need random orbit for what you're describing.

 

[PSYKO_Inc]

Whoa, that Onyx micro sander looks pretty cool, hadn't seen that before. Looks like it would be great for bodywork and paint/rust removal in tight areas. Might pick one up in the future. Does it use a standard roloc adapter like a die grinder?

 

[Astro_Pneumatic_Tools]

Whoa, that Onyx micro sander looks pretty cool, hadn't seen that before. Looks like it would be great for bodywork and paint/rust removal in tight areas. Might pick one up in the future. Does it use a standard roloc adapter like a die grinder?

Yeah, we're the only ones with the design and it's pretty new. It uses as female 5/16-24 spindle because it's a sander first. it can accept roloc holders and work as a surface prep tool, but those roloc holders need to have a 5/16-24 male instead of a long 1/4" shank.

For any GJ users I can send free 320RH2 and 320RH3 (Roloc Holder 2" and Roloc Holder 3") that work with these tools.

Since the motor is inline, there's no gearing transferring the power. It really rips.

 

[alas]

So I'll get the onyx 321 today . Astro, you have a PM.


-E

 

[alas]

So I'll get the onyx 321 today . Astro, you have a PM.


-E

So actually there are slight differences between the two besides length (321 is 1" longer).

The 321 dual action spins up to 16,000rpm while the 320 spins up to 19,000 rpm.

With that considered, will the dual action 16,000 rpm be handled better (slightly) by my compressor?

Or does that specification not really matter in this case? And should I just go for more speed?

Specs:

-E

 

[Astro_Pneumatic_Tools]

So actually there are slight differences between the two besides length (321 is 1" longer).

The 321 dual action spins up to 16,000rpm while the 320 spins up to 19,000 rpm.

With that considered, will the dual action 16,000 rpm be handled better (slightly) by my compressor?

Or does that specification not really matter in this case? And should I just go for more speed?



-E

RPM does not directly correlate to CFM usage. They both have the same motor, the 321 is just spinning a counter weight for orbital oscillation as well so it's max rpm is less.

They use the same amount of air.

 

[alas]

Thanks for the info. I'm such a rookie.

Part ordered (320) and I'll be sure to review it and share


-E

 

[alas]

This little thing is awesome!

I only got to play with it for a little before it got too late and my compressor is too loud to run.

https://vimeo.com/169963234

The size is really nice to work with and it seemed not to vibrate so much the short time I used it. I feel like I could have worked through the entire night with it, to be honest.

The speed control is easy to use and holds its setting well. The tool is much quieter than I expected.

With my old compressor, I can run it consistent for 2-3 minutes before the loud thing kicks back on.

Shout out to Chris from Astro who kicked over the surface prep holders!! Great warm welcoming into the DIY/Garage family. Thank you very much.

I'm pleased



-E

 

[Astro_Pneumatic_Tools]

That's awesome, thanks for posting up Alas.