I’m quite paranoid about the effect of wood dust (including MDF dust) on my health and that of my family.
Bill Pentz has some good information on the subject here.
Some time ago I bought an NVD750 in Axminster’s 40th Anniversary promotion for £399.95.
It came in a similar package to this one with the mobile base and a selection of hoses, stainless steel pipes and nozzles.
I have a relatively small workshop in a single garage so I wanted a single extraction system that could cater for both the high pressure low volume needs of my power tools (including router, circular saw, jigsaw etc) and the high(ish) volume, low pressure needs of my machines (bandsaw, planer thicknesser etc).
For flexibility i needed to be able to connect to both 32mm and 100mm hoses.
The NVD 750 provides 100mm and 51mm options and comes with a 32mm hose with 51mm adaptor attached.
A 51mm blanking cap is provided which blocks either the 100mm (with push on 100mm to 51mm adaptor) or the 51mm inlet, depending on which you want to use.
The cap is retained by a length of wire to avoid losing it.
I am also pretty paranoid about wood and MDF dust and its impact on my health and that of my family, so whatever I chose had to be able to filter very fine dust in the 0.5 micron range rather than just throwing it out of the exhaust into the air.
There are two filters fitted as standard – a red “Filtrex” primary filter and a secondary “Permatex” filter.
In addition to the standard filters, it is possible to use special NVN-4BH HEPA flow bags to filter and collect fine dust. These fit inside the drum over the inlet from the front 51mm inlet:
Before I purchased the Numatic I had some email correspondence with Simon at Axminster, the edited highlights of which are reproduced below:
- The hose size has no relation to the filtration level, the HEPA flow bag can be used with either hose but is only a filter and not a collection bag with the larger hose.
What I didn’t understand from the above is that to use the HEPA bag with the larger hose you have to cut the bag in half and fit it as a filter underneath the motors in the lid. Having it fitted inside the drum as a collection bag will NOT offer any protection
- The central opening (51mm/32mm hose) has to be used if you want to use the HEPA bag as the collection bag.
- With the side opening (100mm hose) you still use the filter but the waste collects in the drum.
- With the HEPA flow bag and 2 head filters the vacuum captures 98.7% @ 0.5µm and 96% @ 0.3µm.
- With the addition of the HEPA module the filtration is 100% @ 0.5µm and 99.95% @ 0.3µm.
- Axminster still recommend using the HEPA flow bag with the HEPA module, if it isn’t the filtration levels will be slightly reduced from the levels listed below and the life span of the other filters will also be reduced.
I have not yet purchased the HEPA module, but I think I definitely will.
It’s also worth noting that if you’re paranoid about the possibility of extremely fine dust passing through the filter, out of the exhaust and into the air, it is possible to vent the exhaust outside through a 51mm hose, which screws on to the outlet in place of the deflector that comes fitted.
The first thing that strikes me about the noise of this vacuum is that most of it comes from the air rushing into the end of the hose, rather than from the motors or exhaust of the vacuum itself.
I don’t have a decibel meter but I would say this is no louder than my domestic Dyson DC07 and if the noise from the end of the hose wasn’t there I think it would be quieter.
I’m quite sensitive to noise, so I’ve always found it more comfortable to wear ear plugs and/or defenders when running the Dyson and my router and this is unlikely to change.
I had thought before I bought the NVD750 that I would be able to choose whether to run one or both motors, but this doesn’t seem to be possible.
The power switch has a clear rubber cover to prevent the ingress of dirt and dust:
There’s a 10m power lead which is fixed securely to the top of the NVD750 to prevent it being pulled out if you wheel it too far from the socket:
The suction of this thing with the small hose attached is quite something – I think it’d have a jolly good go at sucking a golf ball through a garden hose! 🙂
Things I like:
- Fine dust filtering
- Build quality
- Choice of 32mm and 100mm hoses
- Quiet motor and exhaust
- Suction power
Things I don’t like:
- The price – particularly for the HEPA module!
- Noise from small hose (unavoidable though)