Convert Ridgid 2.5 gal comp to 7.5 gal?

[rick carpenter]

I have a Ridgid Mobilaire 2.5 gal compressor http://tinyurl.com/j8hn5ay . It is 9.6A/125V oil-less with 2.1@90, but I cannot find the hp rating (calcs say it could be 1.25 hp but I think that's high). I want to see if I can mount a 5 gal pig I have laying around on it to increase capacity to 7.5 gal. Questions...

1. The Harvest Handy Helper pig has a discard date of 2013, is this important?
2. Would I run the risk of going beyond the duty cycle rating of the motor/pump going to 7.5 gal?
3. Any need of check or ball valves between tanks if I plumb it in series?

If this won't work, no big deal: it's just a finish/trim compressor that works well enough already. The big suitcase that attaches on top (where the pig would be mounted) to carry guns/etc always seemed ridiculous to me. I leave it in the garage whenever I carry it out to a worksite because it makes me kinda look like "That Guy", ya know.

 

[Kev442]

What are you hoping to use it for at 7.5 gallons?
It has a very low fill rate, so it would have to run 10 minutes to fill the pig. I do think you would be exceeding its duty cycle trying to keep 7.5 gallons up to usable pressure for anything besides using it with small air nailers.
That being said, I have been forced to use my little 2 gallon to air up tires while away from home and I am sure I have run it 30 minutes nonstop more than a few times.

 

[md21722]

Some of these tiny tanks are very poorly made and subject to rupture. If it has a discard date, I would cut a hole it in and scrap it. 2.1CFM @ 90 is roughly 0.5 HP with a good pump. Ball valves between tanks are always a good idea. Check valve is only need for the unloader mechanism between the pump and whatever tank its directly connected to.

 

[rick carpenter]

Thanks y'all, looks like I'll keep it as is. I'm using it tomorrow to install my baseboard.

 

[TigerDude]

After the extra tank is filled, It will have nothing to do at all with the duty cycle.