FM-150 Portability
One of the biggest problems with your upright 1HP and larger machines is portability. Sure, many of them come on wheels for mobility, but they are really no more mobile than a bad shopping trolley, and if you don't have a lot of floor space, chances are they aren't going to be going anywhere anyway because of all the other machines or floor obstructions in its way. Enter the FM-150. This mini-dust extractor weighs just over 8kg (18lbs) and comes with a handle allowing you to just pick it up and carry it wherever you like. Take a look at the intro image. You can see the relative size of the machine against the male holding it. I also own a 2HP dust extractor (FM-300) and there is no way I can pick that up and move it around as easily. The integrated carry handle accessible at the top of the unit provides a balanced and comfortable carrying grip.

The footprint of the metal-framed unit is quite small. It measures just over 33cm (L) x 30cm (W) x 30cm (H). In imperial measurement, this is 13-1/4" (L) x 12" (W) x 12" (H). Bear in mind that when in use, the footprint grows because of the inflated collection bag.

The unit is fitted with 4 small castors to roll around the shop floor. Two of the castors have wheel brakes to help prevent movement in use. We found the unit still moves a little when first powered up (only talking an inch maximum) before it settles down and remains fairly stagnant once it gets up to full speed.

Another interesting feature is the inclusion of wall-mounting keyholes in the metal base of the unit. Given the small weight of the machine, you can actually hang it on a wall and get it up off the ground if needed. This would be a good way to mount a unit if floor space is limited, or if you wish to use it on a single preferred machine.. Just hook it up on the wall and away you go, and easily remove it later again for portable use. You may have to remove the wheels for wall mounting however.

Dust Sucking Power
What allows this unit to be so small but still accept a standard 4" dust hose? The answer is the motor. The FM-150 uses a universal brush motor rated at 1HP. Yes, this means the motor is going to be noisier than your regular induction motor, but also means the overall size of the unit is greatly reduced, because the smaller universal motor can deliver more power on a power-versus-size ratio. The noise emission rating from the unit is not actually listed in the tool's manual, and without a noise measuring device, I can only say that it is as noisy as any other 1HP universal motor. Its quite manageable but does require ear protection. It's no where near as noisy as a petrol chainsaw however, but perhaps equal to a mid-range shop or home vacuum, but with less high-pitch whine. Given the benefit of size and portability as a result of using a universal motor, the consequence of the actual added noise level remains relatively tame, in my opinion. Power is controlled via standard ON (green) and OFF (red) buttons on top of the motor component. These are dust protected with a clear rubber cover.

The FM-150 utilizes a contained, 6" steel impeller to provide the reverse airflow into the dust bag. As mentioned above, the plastic air inlet connector accepts standard 4" dust collection hose without any problem, so there is no need to buy reducers or other parts to hook up your hose if you already have spare 4" hose, or use 4" hose in the workshop. The inlet to the impeller is covered by a wire grill to prevent damage to the impeller by large objects, however, I did find that using the extractor on particular machines can pose an occasional problem. When used with the jointer or thicknesser, large shavings or chips can collect on the wire grill causing blockage and reduced efficiency. Let me stress however, the use of the word 'occasional' above, as this was not a 'regular' occurrence. We had no problems in use with any other machines, except for later cleanup of lathe shavings that were clumped together to start with. We had 1 blockage there, but collecting shavings while turning on the lathe was not a problem.

The rated airflow of the FM-150 is listed at 914 CFM. This is a pretty interesting figure because most 1 HP induction motor extractors only deliver around 600 CFM. So the FM-150 claims to deliver around 50% more airflow than the induction motor equivalent. Again, I don't have the tools to measure air flow, but I can tell by feeling the 'sucking' force of the air that it is definitely more than a 1HP induction unit delivers. It achieves this higher figure by spinning the impeller at much faster rates, which creates higher airflow. A conservative estimate of around 4,000 RPM is standard for brush motors of this size, whereas the average induction motor may spin at around 2,800 RPM.

Collection Bag
The dust collection bag on the FM-150 is a woven fabric material and rated to 35 microns, so it's not going to filter out all the smallest dust particles that are collected by the machine. As is the case with most other off-the-shelf extractors in the budget range - smaller particles (mostly non-visible) will still be expelled into the air. It will catch the visible 'coarse' dust of course and save you a LOT of time with cleanup later, but when used in tandem with a ceiling mounted room air cleaner (with 1 micron filter installed), and with a dust mask (where possible), the FM-150 provides a good platform for "practical" dust collection effectiveness. Sure, you can argue that you need less than 1 micron filters on everything that collects dust, but the reality is that most woodworkers do not have the money to invest in such gear, and having any dust collection is certainly better than having none. Finer micron bags (3 - 5 micron needle felt) are expected to be available for this unit in the near future.

The collection bag adds another 60cm or so (23") to the footprint of the machine when in use (i.e. inflated), so take that into account as well. It's usually not a problem because the unit can easily be turned any direction for bag clearance. Bag capacity is 15L. It will require regular emptying as it fills up like any bag extraction system, and it is a good idea to empty it out before it fills up too much to ensure airflow is maintained. With a collection bag at 3/4 full, the unit's capacity to move air may be reduced down to around 600 CFM, so keeping the bag half full or less is a good idea, although at 600 CFM it is still on par with an upright 1HP 2-bag extractor with empty bags!
An occasional full clean and wash of the collection bag will further improve airflow.

Manual
The printed manual is fairly basic and in black and white. However, assembling and using this machine is practically child's play. All you really need to do is attach the castor wheels using supplied nuts and washers, attach the collection bag using supplied bag clamp and then attach your 4" hose (not included), plug in, and away you go. Note that the manual recommends connection the extractor to only one unit at a time and to regularly check the impeller and working parts, including motor brushes regularly to maintain tool efficiency.

In Use
I purchased this tool primarily because I wanted a portable dust extraction solution, and the FM-150 is certainly that. The ease of which it can be carried around from machine to machine, or from workplace to workplace is excellent. No back straining and no lengthy assembly/disassembly procedures to move it from one spot to another or to transport it in a vehicle. In most cases you will only have to unplug the power cord.

I have attached a 4" quick connector to the far end of the collection hose so I can easily connect and disconnect the extractor from most of the my woodworking machines as needed, however, I primarily use this extractor for the miter saw (in conjunction with a "big gulp" dust hood and with the lathe when turning, and especially when sanding. I also often connect it up to my floor sweep to collect dust and shavings at the end of a woodworking day. Additionally, because my router table also acts as a general tool table, I can now connect my removable router table fence to a 4" dust collection source quickly and easily without having to run a dedicated hose from my larger 2HP stationary collector sitting down the other end of the shop.

On its own, the FM-150 may sound noisy, but it comes a distant second to my 3HP router, my 3HP miter saw, and many other power tools that it is used in conjunction with in the shop. Often I can't even hear the extractor because of the greater noise emitted from the tool it is hooked up to. Vibration seems to be in check, but the motor will give off a bit of a 'new motor' smell and you may see some sparks inside the motor assembly the first few times you use the unit. This is normal with new universal, brush-type motors as the tool 'wears' itself in to normal operating use.

Conclusion
As long as you regularly maintain the unit (keep bags emptied and ensure no blockages, check motor brushes etc), you should be able to get quite a lot of use out of the tool. It works best when used as a portable dust extractor, simply because it is designed to be that way, and it achieves that task so much better than any other larger dust extraction system. This, of course, does not count vacuum systems with smaller diameter hoses, they are in a different operational category.

If you have a small workshop or need a portable dust extractor, the FM-150 is hard to pass up, and is very reasonably priced at AUD$169 (Sept 2005) given its performance specifications. I am happy I laid down the dollars to purchase one of these machines. It certainly saves me a lot of hassle moving collection hoses all over the place while I wait for my new "shed" with full ducting to become a reality.