DIY moth traps - any tips for improvements? (1 Viewer)

[400mark]

Like any new hobby, I didn't want to spend a lot of money to find 6 months later I was bored with it, so I found as much info on the internet & read up on the subject.
The information I found in the threads in this forum were invaluable as was the info in all the other moth sites which are now kindly listed under the "sticky".

After choosing to opt for an Actinic set, I decided it would be easier & safer to purchase the light & electrics as a ready made, waterproof set. I purchased mine from Paul Batty & cost under £40 inc p+p. He also kindly provided some plastic for the vanes.

I copied a design I'd seen somewhere based on a a sqare plastic container (I got mine from Wilkinsons for £4). I have cut a hole in the lid & inserted a large funnel (99p) with the bottom cut off. Underneath a smaller funnel is fitted into the bottom of the container for drainage. The light + vane sits above the funnel & in theory the moths fall in!

This was my initial trap, I used it & it worked, but I wondered if it could be improved?

I have read somewhere that painting the inside of the trap white helps? So I have now done this. I have also lowered the position of the light so it sits closer to the funnel entrance, which may increase the catch? & finally I have secured the vane with 2 Bulldog clips + a piece of garden string, as the lamp used to blow over during windy nights (see pics).

Does any one have any design tips for their traps or tips that may help improve this trap?
ie Is there an optimum size for the base of the entrance funnel?

PS It is still my first year of mothing but already I'm thinking it's the sort of hobby that could become addictive.

 

[Surreybirder]

I'm impressed, MarK! Being pretty useless at DIY I bought the finished article from Mr. Batty.
He uses an ingenious system of velcro to keep the 'working bit' upright inside the funnel and it works v. well. He also velcros a small rain shield above the vanes although it doesn't really keep much water out of the trap in heavy rain.
I don't know about painting the inside of the trap... surely the moths are in once they're in, so to speak?
There's been a lot of discussion on UKMoths about the new regulations... apparently the EU is banning mercury from lightbulbs in 2008... the nanny superstate
The talk is all about the new UV LEDs. I cannot say that I know anything about it, but apparently they will weigh next to nothing and run off batteries. So I don't know where this will leave those of us using traditional traps. Paul Batty is quoted as saying that he will have to provide disposal services for used bulbs from the end of this year (if I remember correctly). In other words, it might be worth stocking up on a couple of spare actinic tubes before too long, as the manufacturers will stop making them. (I don't want to start people panic buying before I've done my panic buying!!)
Ken

 

[mothman]

I recon a bigger funnel would help(ooh matron!).If you can't accomodate this with your curent plastic box have a look at Pete Haynes excellent home made Robinson set up on "A few moths at last part 2" page 2 #30 ,there is no reason why this design couldn't be adapted to take your actinic electrics.

Colin.

 

[400mark]

Thanks Ken, I may have to get one or two spares in.

I also thought that once they were in they were in, but I have sat next to my trap at night & put the little so & so's in, next morning were they there? no!
I painted the inside white as I guess the light reflects more & it's not so easy for them to follow the light to find the way out?.

From your comments I guess from the end of 2005 if the bulb stops working you can't just throw it in the bin, you have to dispose of it properly?

Colin, i'd love a bigger funnel, but haven't found one yet!

The box is roughly 45cm long x 35cm wide, the funnel I have is 13cm at the entrance & the narrow part is roughly 9cm wide, is this too large?
A 30cm funnel may be a bit too big for this but I will now be on the look out for something bigger.
Pete's trap that you mentioned is a work of art, I don't think I could manage to build a trap to that standard.

 

[harry eales]

Thanks Ken, I may have to get one or two spares in.

I also thought that once they were in they were in, but I have sat next to my trap at night & put the little so & so's in, next morning were they there? no!
I painted the inside white as I guess the light reflects more & it's not so easy for them to follow the light to find the way out?.

From your comments I guess from the end of 2005 if the bulb stops working you can't just throw it in the bin, you have to dispose of it properly?

Colin, i'd love a bigger funnel, but haven't found one yet!

The box is roughly 45cm long x 35cm wide, the funnel I have is 13cm at the entrance & the narrow part is roughly 9cm wide, is this too large?
A 30cm funnel may be a bit too big for this but I will now be on the look out for something bigger.
Pete's trap that you mentioned is a work of art, I don't think I could manage to build a trap to that standard.

Hello Mark,

You should be able to find a larger funnel at shops or dealers that supply the
Catering Trade, try looking in Yellow Pages for your local suppliers. A 30cm funnel is ample and a 10cm hole at the base should be enough.

I'm not too sure that painting the inside of your trap white is a good idea. All the Robinson M.V traps I have seen, including my own have black interiors.

There will always be a few moths that escape through the entrance hole, but if you have enough egg boxes inside in to which they can crawl, you will find you will have enough moths to keep you busy.

Be warned, not every night is a good one, you will get nights when nothing turns up. Don't let that dishearten you, the next night could be terrific.

However, enjoy your trapping, you wont get tired of it, I can promise you that. Thanks for the info about the EU Regs on bulbs. I have ten M.V. bulbs in stock, and at my age that should be enough to see me through to the time I pop my clogs.

Harry

 

[400mark]

Be warned, not every night is a good one, you will get nights when nothing turns up. Don't let that dishearten you, the next night could be terrific.

Thanks Harry, I had one of these last night + the forecast for the next few nights looks similar, ie COLD!

I have ten M.V. bulbs in stock, and at my age that should be enough to see me through to the time I pop my clogs.

Just out of interest, how long does an M.V. Bulb last?

 

[harry eales]

Be warned, not every night is a good one, you will get nights when nothing turns up. Don't let that dishearten you, the next night could be terrific.

Thanks Harry, I had one of these last night + the forecast for the next few nights looks similar, ie COLD!

I have ten M.V. bulbs in stock, and at my age that should be enough to see me through to the time I pop my clogs.

Just out of interest, how long does an M.V. Bulb last?

Hello Mark,
I have used 125w M.V. bulbs for over 40 years and have found that like most bulbs they do deteriorate over time, and should be replaced periodically, but I think that with frequent use (300+ nights) a year they should last some 3 years before they loose the greater part of their attracting power.

I have never had a bulb actually blow up when in use in adverse weather and I never use a rainshield, however some entomologists have reported that it does happen. Bulbs do get very hot when in use and the internal elements remain very hot for some time after the light is switched off.

Most losses of bulbs are due to moving the trap or accidentally bumping it whilst the internal parts are still hot and very fragile. I always leave the trap to stand for at least 5 minutes before moving it.

'Black light' M.V. bulbs with a Woods Glass envelope, run hotter than ordinary M.V. bulbs and are more prone to cracking in wet conditions, and these should be given a longer period of time to cool down.

Never ever use an M.V. bulb with a cracked outer case, they will work, but they do emit dangerously high levels of UV light. Always destroy such bulbs.

The 12v Actinic tubes used in small portable traps also loose their efficiency after a while and should be replaced every couple of years or so if in frequent use. These tubes never get hot and are safe to move as soon as the trap is switched off.

If I can offer a couple of 'tips', sooner or later you will venture out some distance from home, before you go, check all your equipment by setting it up and connecting it to your generator and run it for a few minutes just to ensure everything is working. Always carry a spare bulb, and a spark plug box spanner when working away from home.

'Sods Law' effects all entomologists, especially when working in places far from home. Several years ago I drove some 60 miles into the Northumberland uplands and set up my trap on the edge of an area of ancient oak woodland and heather moor. It was late July and there was a heavy overcast after a very hot day, in other words ideal mothing conditions. I had everything set up by dusk and was looking forward to a great night. Then Sods Law struck. I couldn't get the generator to fire, what was worse I had forgotten my plug spanner. After an hour of trying to get it to work, I had to pack up and head for home. Driving over the unlit moorland, moths were as thick as snowflakes in a blizzard in the headlights. The next day the generator fired on the first pull on the starter. Grrrrr.

Harry.

 

[400mark]

Thanks for the advice Harry, you had me worried about the "pop your clogs" bit, I didn't realise the bulbs lasted that long.

I have been out shopping & am now the proud owner of a bigger funnel! (found 1 in a auto-parts shop), so will be busy modifying my trap accordingly.

I don't think i'll bother trapping tonight as it's going to be cold & windy.

 

[AndrewParker]

Thanks for the advice Harry, you had me worried about the "pop your clogs" bit, I didn't realise the bulbs lasted that long.

I have been out shopping & am now the proud owner of a bigger funnel! (found 1 in a auto-parts shop), so will be busy modifying my trap accordingly.

I don't think i'll bother trapping tonight as it's going to be cold & windy.

Based on the original Heath design I would suggest that you need to get the Actinic tube as low as possible in the new funnel. If the angle of the funnel is small enough you will find the vanes stay up even in strong wind.

The light output from the current generation of UV LEDs is pathetic compared to even a small Actinic tube. LEDs are going up in light output almost as fast as computer speeds increase, but it will be several years yet before they become economic as an alternative to other UV sources, not least as UV LEDs are expensive.

A friend in Wales has been experimenting with LED traps. Although the catch is very small, he has been trying ideas like hoisting them up into tall trees or placing them inside the bottom of a hedge, locations that an ordinary trap would find difficult. I have not spoken to him for some time, but he had not made any startling discoveries last year.

Andrew.

Edit: Green LED traps are used to monitor whitefly poplations in glasshouses.

 

[harry eales]

Thanks for the advice Harry, you had me worried about the "pop your clogs" bit, I didn't realise the bulbs lasted that long.

I have been out shopping & am now the proud owner of a bigger funnel! (found 1 in a auto-parts shop), so will be busy modifying my trap accordingly.

I don't think i'll bother trapping tonight as it's going to be cold & windy.

Hello Mark,
The ten M.V. bulbs I have should last me thirty years with a bit of luck. By then I will be well into my 90's and doubt very much, if I will be out in far away places moth trapping. If I survive that long I will probably be quite happy to capture a Nursus curvacious in a broom cupboard in the old folks home.

Harry

 

[Pete Haynes]

Home made traps

Mark,

Making a home made Robinson trap is a little fiddly but well worth it. The main housing is a black garden tidy tub from Wickes (approx £6 If I remember rightly), one half of a 2m strip of electrical conduit screwed to the rim at the top sticking up enough to prevent the clear cone from slinding off sideways, a cut off plastic 12" (or 30cm) beer funnel from the Home Brew shop in Aldershot (mail order from www.the-home-brew-shop.co.uk/item1843.htm (£4.70) - paint this black underneath and silver in the throat of the cone, 3/4" brass strip bent to shape and screwed or riveted to the cone to form a bulb support and rain guard support. What started off as the most difficult bit, ie the clear plastic catching cone is now relatively easy. Once I had calculated the shape of the plastic (polycarbonate) halves, checked it against my borrowed trap and produced a template, making new cones is now easy. The halves can be taped together or, as I do, use Mitre Mate or a similar two part instant adhesive - be careful, you only have one chance to get the position right as after a few seconds they are bonded for life! If you need any help give me a shout. I am in the process of making another trap from the same pattern to take a 40W actinic set recently purchased from Paul Batty. This will be for use on some of the heathland I look after. A mechanic friend had given me two working lorry batteries too.

I have found, by walking round my trap two or three times in the evening and popping into it any moths sitting around outside, that some species are very prone to escaping later in the night. I thing the worst so far has been Barred Sallow - up to 80% of them going missing. They are not the only ones by any means. Most, however, once in that's it for the night.

All the best

Pete H

 

[AndrewParker]

There's been a lot of discussion on UKMoths about the new regulations... apparently the EU is banning mercury from lightbulbs in 2008... the nanny superstate
... Paul Batty is quoted as saying that he will have to provide disposal services for used bulbs from the end of this year (if I remember correctly). In other words, it might be worth stocking up on a couple of spare actinic tubes before too long, as the manufacturers will stop making them. (I don't want to start people panic buying before I've done my panic buying!!)
Ken

I had not heard about the ban on mercury in bulbs. Can anyone give me a reference to the EU regulation or draft (I am not a member of UKMoths)? I am surprised that this is a complete ban, as it would outlaw all forms of fluorescent tube and low energy bulb. White LEDs will come in for domestic lighting in a few years time, but I would have thought 2008 too soon for a total ban. Does anyone know what will replace the blended mercury bulbs currently used for street lighting?

Disposal services for fluorescent tubes have been normal in Austria for some time now (Actinic tubes are basically standard fluorescent tubes without the phosphor coat).

Andrew

 

[Surreybirder]

I had not heard about the ban on mercury in bulbs. Can anyone give me a reference to the EU regulation or draft (I am not a member of UKMoths)? I am surprised that this is a complete ban, as it would outlaw all forms of fluorescent tube and low energy bulb. White LEDs will come in for domestic lighting in a few years time, but I would have thought 2008 too soon for a total ban. Does anyone know what will replace the blended mercury bulbs currently used for street lighting?

Disposal services for fluorescent tubes have been normal in Austria for some time now (Actinic tubes are basically standard fluorescent tubes without the phosphor coat).

Andrew

Try
http://groups.yahoo.com/group/ukmoths/message/32113
I don't think you have to be a member to view messages.
Ken

 

[400mark]

"If I survive that long I will probably be quite happy to capture a Nursus curvacious in a broom cupboard in the old folks home".
Nice one Harry! why wait till your in your 90's?

Pete, I will start purchasing the parts to try + copy your design, It could be a long term project that will challenge my limited DIY skills. :stuck:
PS. Where abouts do you get the polycarbonate from?

Ken, I tried the above link, looks like you have to be a member to view this.

 

[Surreybirder]

Ken, I tried the above link, looks like you have to be a member to view this.

The link quoted in the message is:


http://www.dti.gov.uk/sustainability/weee/RoHs_Regs_draft.pdf
though I don't think that's the full story.

Is Polycarbonate the stuff they sell in sheets at Homebase? It seems to come in various grades (thicknesses). I wasn't sure 'cos it says 'keep away from heat' on it.
Ken

 

[mothman]

The link quoted in the message is:


http://www.dti.gov.uk/sustainability/weee/RoHs_Regs_draft.pdf
though I don't think that's the full story.

Is Polycarbonate the stuff they sell in sheets at Homebase? It seems to come in various grades (thicknesses). I wasn't sure 'cos it says 'keep away from heat' on it.
Ken

The transparent cone on a Robinson never even gets warm,i think it must be because the inner cone(usually sprayed silver) is between it and the bulb.

Colin.

 

[Pete Haynes]

Polycarbonate sheet

Hi Mark,

The polycarbonate sheet we bought is made by Bayer Polymers www.sheet.bayerpolymers.com , also www.polcarbonate-sheets.com ,and was bought at a local suppliers, cost approx £25 for a 2m length of width 1.25, enough for at least 6 traps. You can use the odd bits left for a decent size rain shield over the bulb. I'm as much concerned about protecting the moths in the trap from drowning as protecting the bulb! If you would like a paper template for the catching cone let me have your address and I'll send you one. I will find out the thickness we purchased from my fellow moth'er Johann.
I haven't bothered with vanes yet as it doesn't seem to make too much difference (comparing my trap with a bought one, but then it can be difficult to tell).
I used Humbrol enamel, matt black and silver, for painting the funnel of the first one but have since purchased the same colours in spray form from a garden centre. The enamel sticks well to the plastic funnel but I haven't tried the spray, thought if it does what it says on the tin it will be fine!

All the best

Pete H

 

[AndrewParker]

The link quoted in the message is:


http://www.dti.gov.uk/sustainability/weee/RoHs_Regs_draft.pdf
though I don't think that's the full story.

Ken

Thanks for the link.

The draft regulation in question is due to come into force on 1 July 2006. However Schedule 3 list specific exceptions to the regulations:

SCHEDULE 3 Regulation 4 (2)
1. Mercury in compact fluorescent lamps not exceeding 5 mg per lamp.
2. Mercury in straight fluorescent lamps for general purposes not exceeding
- halophosphate 10 mg
- triphosphate with normal lifetime 5 mg
- triphosphate with long lifetime 8 mg
3. Mercury in straight fluorescent lamps for special purposes.
4. Mercury in other lamps not specifically mentioned in this Schedule.​

4. would apprear to include MV bulbs, and either to include Actinic or they would fall under 3. Therefore there appears to be no problem! It is not clear if these regulations have come into force, as this link contains no date of entry.

Andrew.

 

[harry eales]

Hi Mark,

The polycarbonate sheet we bought is made by Bayer Polymers www.sheet.bayerpolymers.com , also www.polcarbonate-sheets.com ,and was bought at a local suppliers, cost approx £25 for a 2m length of width 1.25, enough for at least 6 traps. You can use the odd bits left for a decent size rain shield over the bulb. I'm as much concerned about protecting the moths in the trap from drowning as protecting the bulb! If you would like a paper template for the catching cone let me have your address and I'll send you one. I will find out the thickness we purchased from my fellow moth'er Johann.
I haven't bothered with vanes yet as it doesn't seem to make too much difference (comparing my trap with a bought one, but then it can be difficult to tell).
I used Humbrol enamel, matt black and silver, for painting the funnel of the first one but have since purchased the same colours in spray form from a garden centre. The enamel sticks well to the plastic funnel but I haven't tried the spray, thought if it does what it says on the tin it will be fine!

All the best

Pete H

Hello Peter,

If you bore a hole of suitable size in the base of your trap you can insert another funnel directly below the bottom of the entrance cone, a small piece of perforated zinc or fine wire mesh inserted into the lower funnel will let any water through but keep the moths in.

Vanes above the bulb I would recommend, a lot of micro's and carpets alight on them and a quick puff of breath will make them drop into the trap. Vanes are also useful for catching some of the larger species of moth which zoom over the trap and disappear into the darkness again. The vanes on my trap rise 18" above the entrance cone of my Robinson Trap.

They are easy to make and the materials won't break your bank account.

Harry

 

[Surreybirder]

Thanks for the link.

The draft regulation in question is due to come into force on 1 July 2006. However Schedule 3 list specific exceptions to the regulations:

SCHEDULE 3 Regulation 4 (2)
1. Mercury in compact fluorescent lamps not exceeding 5 mg per lamp.
2. Mercury in straight fluorescent lamps for general purposes not exceeding
- halophosphate 10 mg
- triphosphate with normal lifetime 5 mg
- triphosphate with long lifetime 8 mg
3. Mercury in straight fluorescent lamps for special purposes.
4. Mercury in other lamps not specifically mentioned in this Schedule.​

4. would apprear to include MV bulbs, and either to include Actinic or they would fall under 3. Therefore there appears to be no problem! It is not clear if these regulations have come into force, as this link contains no date of entry.

Andrew.

I hope I'm not breaching copyright but someone on UKmoths quoted Paul Batty's response to someone who made much the same point: