Sunday, 29 March 2009

Eliet Minor shredder – 1 year on report

Around a year ago I published a couple of reviews on the Eliet Minor garden shredder. I thought that it would be useful to post my experiences with the shredder over the last year or so.

A year ago I bought an Eliet Minor garden shredder and concluded that I was happy with its performance – go here to read my previous reviews.

Am I still happy with it?
After a full year of use I am still very happy with the shredder and do not regret buying it at all. It gets through a prodigious amount of material in an hour or two so I have not had to use it too often, which was one of the reasons I bought it in the first place.

Does it produce good compost?

Yes – the shreddings compost down quickly and while some long’ish (about 6”) woody bits do find their way through the multi-purpose screen these are either easy to pick out and feed back through the standard screen or can be left in – they are quite heavily abraded as they pass through the blades and I have found that they tend to rot down more quickly than if they were simply cut to the same length and put on the compost heap.

I have, however, learnt a few things about the Minor in the last year:

Using the screens

I have found it necessary to swap between screens quite regularly as the standard screen does not like much in the way of wet and mushy material going through it – it quickly clogs up. It is not entirely obvious, but the multi purpose screen only fits in one way round and the as supplied standard screen fits more easily one way round than the other. To help swap them over quickly I have found it helpful to mark the top of the screens so that I put them in the right way round – as in the photo below.

Both screens are robust, being made from solid steel and tight fitting. I have thus found it helpful to have a small lump hammer and a crow bar to hand to speed up the removal and fitting process with gentle taps and tugs here and there to facilitate the changeover.

I have mislaid the screen securing pins a couple of times when changing over screens – on the last occasion I found one in the compost heap…

Really, really mushy material
On a couple of occasions I have wanted to shred the wet and mushy contents at the bottom of the pile. These even blocked up the multi purpose screen, so I simply take out the screen and push it through the blades without any screen in place. Since the area is protected by the micro-switched grill I can not see that this is dangerous. In any case I have only had to put a very small amount of material through this way.

Safety switches

I can confirm that the micro-switches on the grid protecting the outlet and the lever near the inlet both work. On occasion I have accidentally knocked the lever near the inlet and it immediately cuts off the engine. A couple of times the engine has been reluctant to start because one of the micro-switch’s contacts are not made properly. Just popping them back into place by re-closing the lever or grid sorts out the problem.

Is there anything not to put into the shredder?

Apart from the obvious things like stones the only plant material that I have found to avoid are Phormiums’ tough, sword-shaped leaves. These long fibrous leaves have properties a bit like flax (hence their colloquial name of New Zealand flax) and you could probably make rope from them. In any case in large quantities (we have several in the garden and they produce armfuls of prunings at this time of year) they tend to act like rope around a propeller, so I either feed them in very sparingly with a large amount of really woody material or use my old Scheppach Lonos 2 to crush them up enough for the compost heap.

Otherwise it takes everything in its stride.

Be a bit careful about what you shred…
With the low material flow rates through my older shredders I never found any fumes coming off shredded material to be a problem. With the Minor, however, with its large flow rates combined with its truly shredding action I found that shredding a large old Ivy plant caused some fumes to avoid. The shredder cuts finely and exposes a large surface area of material for composting, but this can also release a lot of fume if the material is prone to produce it – the Ivy clearly did. A bit of research indicated that shredding fresh Laurel leaves can also produce an unpleasant fume, so I now let Laurel cuttings go brown before shredding them.

Health and safety

Through long years of working in engineering environments I automatically wear safety glasses when using anything like this. I also wear ear defenders, along with a dust mask when shredding dry material. I double glove (eg a pair of thin nitrile coated inner gloves and a large pair of heavy duty outers) as I find that to keep up with the machine’s appetite for material it is impractical to check what you are picking up too closely and we have a lot of seriously thorny material in our garden. This solution keeps pretty much everything out.

Starting the engine

My Minor is fitted with the Briggs & Stratton engine option. This is started with a pull cord and as with all my petrol engined garden machinery it can be a bit reluctant to start after a long lay off. I don’t find this machine to be any better or worse than others in its ease of starting. When hot it restarts easily with a single pull of the cord.


Remember that this is a petrol driven engine and that it produces exhaust fumes. Standing by it while it is running for a long time can be a bit unpleasant, so I take regular breaks and work in a well ventilated (draughty even) area.

I am very happy with my choice and anticipate many years of service from it.

Saturday, 28 March 2009

Maintaining and upgrading my desktop PC for photography – Part 2: Making the PC quieter and improving CPU performance

Having done some simple software system maintenance which successfully boosted the system’s performance I decided that before doing much in the way of hardware improvements I would like to make the PC quieter; which led me down another speed enhancing route that I had not foreseen.

I watched a series of videos on making a PC quieter on Quiet PC’s web site; go - here - if you would like to watch them.

These videos did several things; they made me much more confident about digging around in the guts of my PC and gave me a whole lot of clues as to how to quieten my PC. Essentially most of the noise from a PC comes from the various cooling fans used on the case, CPU, graphics card, power supply etc etc.

One tip from the videos was that there is usually a switch in the BIOS that can turn on a CPU fan control circuit which will vary the fan speed (and thus noise) with CPU temperature. After a bit of delving I found the control in my BIOS and turned it on. This certainly worked and every time I turned on the PC from then on the fan started out at full (noisy) tilt and backed off after a few seconds – which initially made me think the PC had died. This made the system much quieter, but highlighted that the single 80mm case fan was pretty noisy.

To try to see how much work the fans were doing I found a really useful free utility called “SpeedFan” which essentially reads all sorts of useful information on temperature, fan speed and power supply voltages which it displays in real time. If you want to have a look at it and download a copy then go – here - where you can also make a donation to support Alfredo Milani Comparetti’s work. Usefully SpeedFan puts a digital readout of the CPU temperature in Window's system tray so that it is easy to keep an eye on it while running other programmes.

With the variable CPU fan speed function turned on I became aware that it was varying quite a lot – and the variable noise levels were almost worse than the previous flat out fan noise, but it did tell me whenever the CPU was getting hot. This audible warning combined with SpeedFan’s output made me aware that the CPU was getting pretty hot during intensive Lightroom and Photoshop work and that the hot CPU periods seemed to coincide with some of the sudden unexplained slow downs I was still experiencing with Lightroom.

The screen shot below shows that the CPU was regularly getting up to around 60°C and was usually around 47-50°C when doing anything much. It also shows that my power supply voltages are nearly out of spec, which might also contribute to erratic performance.

I read that Intel P4 CPUs don’t burn out when the get too hot – they just slow down until they cool down again and I guessed that this might be happening inside my machine.

So to reduce the noise and to improve the CPU’s cooling I decided to change the CPU cooler fan from the noisy Foxconn one that came with it for an Arctic Cooling Freezer 7 Pro, using Arctic Silver Ceramique heatsink compound and Arctic Silver’s Arcticlean cleaner to remover the old thermal paste from the CPU and prepare it for the new installation. I also bought three Hiper 80mm case fans, along with silicone Acousti mounts to reduce the transmission of fan vibrations to the case. These replaced the single input fan and added in two output fans which the case had the fittings for, but were not installed before – thus drawing more hot air out of the case. All of this cost about £40 from eBuyer and eBay.

With a huge amount of trepidation I swapped over the CPU cooler – it was much easier than I thought although I am not convinced that I have got the attachment clips in place totally correctly. The clips rotate and I could not find a positive click stop to tell me when they were tightened properly, but it seems to work.

The photos below show the old Foxconn CPU cooler (along with the original set up before I started any of this work and the empty fan installation locations) and the new Freezer 7 Pro cooler and exhaust fans installed (along with various other modifications that I will be talking about in later postings).

What was the result?
The whole PC is now much quieter, but I think I can make it quieter still by reducing the voltage to the case fans a little, which reputedly reduces the noise a lot without reducing the airflow much. I plan to use some Zalman Fanmate variable fan speed controllers to achieve this.

More crucially, according to SpeedFan, the CPU now operates at around 40-44°C most of the time and does not go much above 50°C when running intensive photo processing work – so it looks as if the new CPU cooler is much quieter and, along with the increased case cooling from the extra fans, is reducing the CPU temperature by 7-10°C. This does seem to reduce the unexplained slow downs while using Lightroom further, but not quite completely.

All in all I am happy with these modifications – the PC is much more pleasant to live with and works better.