Robinson Moth Traps

[GreyChi]

Robinson Moth Traps:

This year we decided that it was time to retire our old Robinson moth trap and next year invest in a new trap incorporating the now standard Edison screw fitting Mercury vapour bulbs. After asking Steve Hind if he had any recommendations he suggested I might put the same question to members of the group. We would welcome any suggestions for a good, sturdy, reliable, mains operated trap at a reasonable price. It would be operated in the back garden, so mobility is not an issue.

Merry Xmas and a Happy New Year to all our members.

[AlexCropper]

Hi,

I have had a quick Google to have a look as I'm also curious myself.

I found that ALS has a Robinson Trap for £235 which has Edison Screw thread mount. They also have a model for £305. No idea if they are any good or not.

Here's a link: http://www.angleps.com/mothtraps.php

Alex

[melbellingham]

Hi,

Is it possible to obtain a new Robinson Trap ''at a reasonable price'' ?

I have seen them advertised at anything between £305 and £360. If you consider that reasonable, the answer is yes, and you should be able to get one from any of the usual outlets. Anglian Lepidopterist Supplies (ALS) as already mentioned (less than £320 inc P&P for their professional trap and about £250 for their economy trap), is a company I have always found to be very reliable.

Before you spend that amount though, is a new trap essential? Are you changing your trap simply because you can no longer purchase bayonet fitting lamps? Edison Screw (ES) type lamp holders are readily available for a few pounds, and with a few tools easily fitted.

Are the base, collar and funnel in reasonable condition, or do any of them require replacing?

I have made all of my traps including Robinson types, which involved making the collars (the polypropylene transparent cones) to fit the bases I used, although I did buy the funnels from Bioquip (no longer trading unfortunately). All of the electrics were purchased as DIY kits, and assembled as required. However, the electrics can be purchased ready assembled if you prefer, but that pushes the price up a bit.

My Robinson style traps have cost me less than £100, were made in a day, and I have added modifications to the funnels, to make catch retention more effective. I think the holes on most traps are far too big.

Mel.

[SteveH]

Hi Folks,

Interesting topic and I note the total omission of references to Watkins & Doncaster, probably the original supplier of all things moth-trapping related ..... alas, their product range has always been and remains vastly over-priced and I'd never go there for anything.

ALS are, I'd say reasonable in pricing terms and you get what you pay for. I recently posted on here that our original Robinson 'passed away' late on in the season after 21 years of loyal service at home and around Europe and for swiftness of replacement, went with a £300 device from ALS which has proven to be a worthy piece of kit though its a tad smaller in diameter compared to the old Robinson.

Mel speaks of making his own traps, which is of course an attractive and much the cheapest of 'trap' alternatives. When we had a second trap, all we used was a large rubbish bin with a bit of Perspex on the top with a hole in it where the light went. The late John Raines didn't have a bought trap to his name and used old wooded tea chests as his catching boxes, with again Perspex as the top. Less rustically, a colleague at work built his own and to the layman it would easily be taken for a commercial alternative - it was brilliantly engineered and looked exactly the part!

There is another alternative too, and one we now use on foreign trips as these days not all bulbs need any accompanying electrics other than a plug to go into the wall. We take a bulb on the end of some cable and use either a white wall or a sheet to allow the moths to settle onto. Bulb plus plug plus length of cable ..... £15 or thereabouts.

Plenty of choice - choose your weapon !

Cheers,
Steve

[Kevin]

Hi Steve,

I'm interested in your portable bulb that doesn't need electric box.
What type of bulb is it? Can this be done with a 125 MV bulb or a UV strip light.
Any information on light airport friendly kit would be greatly appreciated.

Happy Christmas.
Kevin.

[GreyChi]

Thanks to everyone who replied to my enquiry. It certainly provoked an interesting response.

Our attempts to rejuvenate the trap started by purchasing a simple plastic adaptor to convert the two-pin socket to an Edison Screw fitting. When this arrived we found we couldn't insert it into the two pin socket as the superstructure over the two pin plug area was too larger diameter. After grinding this down to make it fit, we found that the adaptor increased the height of the lamp so that it wouldn't fit in the inverted Pyrex beaker that acted as a rain guard. We were also worried that the simple plastic converter would not withstand the heat of the MV bulb. Simply changing the socket to a screw fitting looks possible, but a little more difficult, as it seems to be mounted in a solid looking waterproof system.

Building a new trap sounds attractive and I have, in the past, built several traps, circa 1980/1990 era, but I'm slightly older now and the thought of purchasing a brand new trap seems more attractive.

However there's a few months before the next season starts, so plenty of time to make up one's mind.

Thanks again for all your comments.

[SteveH]

Hi Folks,

In response to Kevin's query, we use a 160W 'self ballasting' bulb.

These lamps use a special built-in filament coil that controls both starting and operating currents, so there is no requirement for intermediate hardware traditionally required for MV lights.

They are widely available; Googling should bring back any number of sites with additional information and costs etc;

Happy Christmas all.

Cheers,
Steve

[melbellingham]

Hi,

More information that some might find useful:

I've used 160W MBT (Mercury Blended Tungsten) lamps many times over the years and found them to be very effective. As Steve states, they do not require additional equipment, but they do tend to run extremely hot. I have used 125W MV lamps for years, and although at times they have been subjected to wetting by rain, I have never had one that has cracked. I have however lost three 160W MBT lamps, as they do not stand up to any amount of wetting, even if only slight. This is only a problem of course if you use your trap when it is raining.

Another alternative, using the same principal of operation described by Steve, is a low energy Actinic lamp. I have used two different lamps at home, especially during the long winter nights, when a trap could be on for up to 15 hours. They use far less electricity, do not run hot, and as long as the rain does not get into the electrics, can be used in all weathers.

The lamps I have used are a 25W Black Actinic (very low visible light) and a 20W Compact Actinic Lamp, which gives off light similar to an Actinic tube. These lamps have ES threads and fit into suitable lamp holders, and no chokes are required. I now much prefer the 20W Compact Actinic, and although the catch will not usually be as good as with 125W MV lamps, I can remember one night when I used several traps on Fenn's Moss, where I had 125W MV and 20W Compact Actinic traps separated only by about 50 metres, and the 20W CA had the better catch.

The image attached is of my DIY Robinson Trap with 20W Compact Actinic lamp. It is slightly misleading as the photo was taken just before darkness, with flash, so the light is washed out a bit.

Most of my DIY trap/electric equipment is obtained from Paul Batty, who has a website that anyone interested in upgrading or making their own equipment might like to look at. He does not sell Robinson Traps, but he does sell other types, either fully assembled or as kits. Paul can supply all of the lamps mentioned above, along with lamp holders and lots of other fittings.

http://www.pwbelg.clara.net/mercury/index.html

Plans for a DIY Robinson Trap, and a template for making the polycarbonate cone can be found on a website run by bird photographer Tony Collinson.

http://www.tcdigitalphotography.co.uk/d ... _trap.html

Best Wishes.
Mel

DIY Robinson Trap with 20W Compact Actinic lamp

[Kevin]

Thanks Folks,

I had no idea that such vast range of lamps were available.
I guess those emitting most UV light are the best for moths.

Regards,
Kevin.

[JohnR]

I have just made a Robinson Trap out of an old dustbin using the links provided by Mel. Total costs were around £140, the vast majority being the electrics, but this could have been cheaper had I not gone for a waterproof choke and not asked for modifications so it could be used with a generator.
Regards, John



[quote="melbellingham"]Hi,

Most of my DIY trap/electric equipment is obtained from Paul Batty, who has a website that anyone interested in upgrading or making their own equipment might like to look at. He does not sell Robinson Traps, but he does sell other types, either fully assembled or as kits. Paul can supply all of the lamps mentioned above, along with lamp holders and lots of other fittings.

http://www.pwbelg.clara.net/mercury/index.html

Plans for a DIY Robinson Trap, and a template for making the polycarbonate cone can be found on a website run by bird photographer Tony Collinson.

http://www.tcdigitalphotography.co.uk/d ... _trap.html

Best Wishes.
Mel

[JulianB]

Impressive, especially as all commercial stock seem to have been snapped up at the moment. it's even got baffles and a decent rain guard.

Let us know how you get on with it - tonight would be an excellent night for your official launch, judging by the temperatures right now!

Cheers, Julian

[A_Neal]

Hi all,

Great looking trap John. I’m not great with electrics so would like someone who understands this sort of thing to give me some help. I’ve got a 20w actinic skinner trap at the moment and it has done incredibly well - around 250 species in just under 12 months but I have been thinking whether I could get a better bulb. Steve Holmes mentioned that he has an 160w self ballasted bulb which seems quite appealing to me. So would I potentially be able to run this bulb from the mains with the trap I’m using?

Many thanks,
Alex

[JohnR]

Hi Alex,
I didn't do any electrics, all supplied fully wired by Paul Batty. Regarding the 160w self-ballasted bulb, I would suggest you phone or email him, he is very helpful.
Cheers John

[A_Neal]

Thanks John for the suggestion. Just found Paul Batty’s website on google. It’s a great website and very interesting and informative.

Regards,
Alex