Air Tank Or Battery Powered Compressor?

As you all know I am an innate over thinker and this weeks dilemma is centers around the limited space in my trailer.

I have one of those Harbor Freight air tanks strapped down in the front of my trailer as that seems to be the best place for it.

At present I use a Mongoose BMX bike as my pit bike but I'd like to bring one of my small motorcycles (62 Honda 90 or 75 Yamaha RD125). Both of the bikes mean I need to move the air tank somewhere and as it's a bit wide I don't want to put it on the side.

So this got me thinking how good are those battery powered compressors? How quickly do the fill up a tire?

Note the Datsun runs 13" tires so not much volume but when I do need to add air the tank does this almost instantly.  My typical routine is to overfill the tires by a few pounds and then drop them down, so I don't need much air.

I use a Viair that runs off the car battery. 

The battery-powered ones vary a lot.  I have both the 12v and 18v Milwaukee versions -- the 12v is OK, decent for adjusting race tires by a few pounds.  I once refilled a trailer tire from basically zero with it, it did manage it but took forever and completely drained the battery.  The 18v one is great, it will take an 18" Hoosier from single digits to 30 psi in ~ 30 seconds or so.

https://www.amazon.com/dp/B0B1VHG484

Not what you asked, but years ago a buddy went circle track racing. To save trailer space , he added a nitrogen cylinder in one forward corner and ran he pneumatic tools off that, as well as inflating tires with it.

For me, the main reason I use a tank is that (a) it is sufficient and (b) I fill it with dry air. Any trackside compressor is going to pump all the humidity in the air into the tire, and, here in the south, that can be pretty significant. I tend to gravitate towards the simplest solution, and I like that the simplest option is also the theoretical best on-track. 

I used to drag around the air pig.  Once I used EastsideTim's Ryobi 18V inflater at the challenge I was sold on them.  No, it isn't a replacement for an air compressor.  For ll the shifting a few lbs stuff that happens at the track I'll take the extra space back in the car form the air pig.

In reply to DeadSkunk (Warren) :

Qualifies as the ultimate air tank.

Toyman! said:

I use a Viair that runs off the car battery. 

 

Me too, it would take a 13 inch tire from zero to way overfilled in a minute, definitely less than two. Love it. I always recommend them in these discussions. My biggest problem with it is leaving it run too long, and having to bleed off a bunch of air after I fill the tire. 

The Viair one that plugs into the power outlet/lighter is not supposed to be as powerful. 

Cordless Ryobi 18v works for me.

In reply to codrus (Forum Supporter) :

How long does the battery hold a charge? I.E. can I leave it on the trailer for months?

It's amazing how quickly a common large bore bicycle pump can inflate a car tire.  The battery doesn't go bad, either.

New problem, I can't seem to find one.

Pete. (l33t FS) said:

It's amazing how quickly a common large bore bicycle pump can inflate a car tire.  The battery doesn't go bad, either.

 

New problem, I can't seem to find one.

This is what I use for small adjustments, there's almost no setup time and it adds 1psi in about 3 pumps even at higher pressures. It's a great backup option to have in the car, but for anything more than small adjustments it can get tiring, so I use a 12v compressor that runs from the car's cig lighter socket for that. I have a very compact one I got as a gift, it would be too slow for larger-volume tires but it's enough for low-profile 18s.

Tom1200 said:

In reply to codrus (Forum Supporter) :

How long does the battery hold a charge? I.E. can I leave it on the trailer for months?

This is why I still use the Viair. I know I would forget to charge it and then when I needed it the battery would be dead. 

codrus (Forum Supporter) said:

The battery-powered ones vary a lot.  I have both the 12v and 18v Milwaukee versions -- the 12v is OK, decent for adjusting race tires by a few pounds.  I once refilled a trailer tire from basically zero with it, it did manage it but took forever and completely drained the battery.  The 18v one is great, it will take an 18" Hoosier from single digits to 30 psi in ~ 30 seconds or so.

https://www.amazon.com/dp/B0B1VHG484

 

Honestly for this use case I think the M12 would be better. The M18 is super quick but as a result isn't great at precision with small pressure changes / small air volumes.

100% pump over tank. I don't think my air tank has left the corner of my garage in close to a decade, I routinely forget I have it until I go digging around for something else. If you already have a battery tool collection at home, get whatever works with those batteries and just toss a battery in the trailer while packing. Or you might be bringing one already, attached to some other tool.

I was also contemplating mounting the air tank up in the nose/frame of the trailer. There is a dead spot in between the spare tire holder and the box where an air tank would fit. Of course that is yet another thing that would be added to my to do list........which already has enough on it.

dps214 said:

Honestly for this use case I think the M12 would be better. The M18 is super quick but as a result isn't great at precision with small pressure changes / small air volumes.

IME for precision and consistency you want to go a couple pounds over and then bleed down with a gauge in either case.

Tom:  The Milwaukee batteries are lithium, and hold a charge reasonably well.  The best option, though, is to get an inflator that uses the same batteries as your battery impact wrench so you can swap them around.

84FSP said:

I used to drag around the air pig.  Once I used EastsideTim's Ryobi 18V inflater at the challenge I was sold on them.  No, it isn't a replacement for an air compressor.  For ll the shifting a few lbs stuff that happens at the track I'll take the extra space back in the car form the air pig.

Came here to say this.

codrus (Forum Supporter) said:

dps214 said:

Honestly for this use case I think the M12 would be better. The M18 is super quick but as a result isn't great at precision with small pressure changes / small air volumes.

IME for precision and consistency you want to go a couple pounds over and then bleed down with a gauge in either case.

Tom:  The Milwaukee batteries are lithium, and hold a charge reasonably well.  The best option, though, is to get an inflator that uses the same batteries as your battery impact wrench so you can swap them around.

I mean yeah but with the m12 you can pretty reliably set them 1-2psi over to bleed down. With the M18 if you're trying to just add 2-3 psi you might get the pressure you set or you might get 3 psi over and then you get to spend 30s bleeding it back down. And that's with wide 18" tires, on narrow 13s it's going to be even more sensitive. But it is awesome for actually filling tires, I just know that if I'm trying to do precision work it's not going to go well and I should just run it manually.

I love my m12 tools. Haven't tried the m12 compressor, but I think it's not the right tool for the job

Haven't be able to afford to step over to the m18 for the bigger stuff, but I still have the Kobalt 24 for that. 
The Kobalt 24 compressor was a good physical sixe, and did a good job. But every time I forgot to take the battery out after use, it killed the battery. After it took the second battery down so low it would not accept a charge, I threw it away, so I would not be tempted to use it again!!! 

dps214 said:

I mean yeah but with the m12 you can pretty reliably set them 1-2psi over to bleed down. With the M18 if you're trying to just add 2-3 psi you might get the pressure you set or you might get 3 psi over and then you get to spend 30s bleeding it back down. And that's with wide 18" tires, on narrow 13s it's going to be even more sensitive. But it is awesome for actually filling tires, I just know that if I'm trying to do precision work it's not going to go well and I should just run it manually.

My M18 inflator is actually very consistent, it's basically always within half a psi of the target number that I dialed in.  My M12 was also consistent when it was new, but after a couple years banging around in the trailer it's gone out of adjustment.  That was actually the thing that prompted me to go buy the M18 -- the M12 still works, it just overshoots now.

84FSP said:

I used to drag around the air pig.  Once I used EastsideTim's Ryobi 18V inflater at the challenge I was sold on them.  No, it isn't a replacement for an air compressor.  For ll the shifting a few lbs stuff that happens at the track I'll take the extra space back in the car form the air pig.

My Ryobi inflator can fill an entire NASCAR tire from empty with the car's weight on it. It wasn't exactly fast, and it used about half a battery, but that's a lot of air. I was impressed. I mostly use it for topping off pressure at the track and it's perfect for the job.

I have a small 12V compressor that hooks up to the car battery with clamps, rather than the usual accessory plug. Works great, is compact and I don't have to worry about keeping a tool battery charged. The cord and hose are long enough to reach all 4 tires easily.

How about an old fashioned bicycle pump?  Not the little frame mounted one, a real full size one?  They will pump a car tire and have a built in gage. Blackburn and schwinn are my favorites.

porschenut said:

How about an old fashioned bicycle pump?  Not the little frame mounted one, a real full size one?  They will pump a car tire and have a built in gage. Blackburn and schwinn are my favorites.

I have a good bicycle pump and it did occur to me to put it in the trailer.

I've got a small solar setup in my trailer that allows me to keep batteries charged and run a small AC powered air compressor.