Crispo 8 Gallon 2.5 HP Heavy Duty Air Compressor (CRSTANK)

For odd jobs around the home, a small, light duty compressor will most likely do the job. However, for framing jobs, installing trimwork, flooring or renovation work, a larger capacity, heavy duty compressor is really the way to go. A high CFM rating, large tank and oil-lubricated motor give better tool performance.

The Crispo 8 Gallon 2.5 HP Heavy Duty Air Compressor (CRSTANK) is a compact unit, roughly measuring 20" all around. It's solidly built, with an all steel frame and twin tanks. It rests solidly on two thick rubber feet and two large 8" rubber wheels, which serve to add stability to the compressor, reduce vibration, and perhaps add some sound dampening effect. The CRSTANK has an oil-lubricated induction motor. While an oil-lubed motor requires a bit more maintenance than an oil-less motor, they're known to last longer. The motor delivers 4.1 CFM at 90 PSI, has a maximum pressure of 250 PSI, and a 75% duty cycle (which means the compressor is designed to run for 75% of the time and sit idle 25% of the time). This is quite adequate to drive two framing nailers at one time, particularly on smaller framing or reno jobs. A finish carpenter or furniture maker using a brad nailer would be able to run this compressor all day long without a problem. The pump cuts in at 115 PSI, cycles off at 150 PSI, and runs at 3,450 RPM, which I find somewhat high compared to other heavy duty compressors. I assume that this higher speed will make for a somewhat hotter running motor. However, with a large 8 gallon tank capacity, the motor shouldn't be cycling on and off as frequently as on the more common 4 gallon compressors.

Convenient tilt-up handle

Large 8" wheels for easy manoeuvrability

At 92 pounds, this is one heavy compressor. Thankfully it has a set of 8" wheels and a foldaway handle to facilitate movement around the job site. The large wheels make it easier to manoeuvre the compressor over rough terrain strewn with all manner of construction debris. Getting it into and out of the truck is easy if you have a set of truck ramps, otherwise you'll need an extra set of arms to help you out. Two metal side handles make this an easy job. I did find the foldaway handle to be a bit too low for my 6' frame. The top of the handle is only 29" from the ground, so I have to slouch down when moving the compressor. It will obviously be less of an issue for shorter folks. On top of the compressor is a convenient accessory tray, large enough to hold various small tools or several boxes of nails.

Nice storage tray atop the compressor

A bit awkward to fill up the oil reservoir

The oil plug is located right below the air filter, which makes adding oil a bit of a trick (the air filter gets in the way of the funnel). At least the air filter is easily accessible; it's of a standard size and both inexpensive and easy to replace. At the bottom of the compressor pump housing is a site glass through which you can see how much oil is in the sump. Unfortunately the wheel covers part of the site glass, making it difficult to get a good reading. I would have much preferred a conventional oil dip stick for checking the oil level.

Site glass partially obstructed by wheel

Easy access to the on-off level

The on/off lever, located on the right side of the unit on the front of the pressure switch, is easily accessible. At the back of the pressure switch is the safety valve, somewhat more awkward to access. The tank drain valve is located at the bottom center of the lower tank, as it is on virtually all compressors. There is really no other place it could be located, as it has to drain the lower tank. I've noticed that a lot of guys pull the safety valve at the end of a work day to release air pressure in the tank, rather than venting pressure from the drain valve. I think they do this because the safety valve is easier to reach (as on the CRSTANK). This likely puts undue wear on the safety valve, whose purpose is to prevent failures by automatically relieving pressure when compressed air reaches a predetermined level.

Safety valve is behind the pressure switch

Drain valve in usual spot

The control panel is located up front. In between the air pressure gauge and the tank pressure gauge are the air regulator dial, and two air outlets. This is a good arrangement - everything is easily visible at a glance and the controls are right at hand. Because the gauges range from 0 to 250 PSI, the markings on the scales appear very close together, making them somewhat hard to read, particularly in less than ideal lighting.

Control panel up front and easily accessible

Dials are easy to read

The CRSTANK comes with a container of oil; you'll need to break-in the motor before using the compressor. It only takes half an hour and is clearly outlined in the user guide. When first started the compressor takes almost two minutes to fill the tanks; thereafter the tanks recover in about 30 seconds. At 3' from the tank I measured the decibel level at 102.5, loud enough to warrant hearing protection if you're working in close proximity to the compressor.

I used the CRSTANK with a Samona ROK 3-1/2" Clipped Head Framing Nailer to sink 3-1/2" nails in spruce framing and 2" nails in 3/4" sheathing, and then with a Bosch 18 Gauge Brad Nailer to pin edge moulding to plywood without any problems whatsoever. While the CRSTANK has a couple of minor drawbacks, and only comes with a 90 day warranty, it's nonetheless a well constructed unit that puts out a high volume of air and has a large storage tank. It's ideally suited for a one or two person crew doing light framing jobs, finish carpentry, flooring or renovation work, and should be a standout in a small one or two person workshop.

Reviewed June 2011