DIY wasp killer device

[Jeremy Harris]

We had a small problem at the old house, wasps had started to build a nest in a corner of the roof, flying in and out via a small gap in the facia board.  This is right next to the drive and I spotted them yesterday when laying the gravel, and as it's right next to the entrance to the house there was a high risk of getting stung later in the year, when they tend to get more aggressive.

 

Last time we had a similar problem, on the other side of the house, above our bedroom window, I didn't spot it until late in the summer, by which time the nest was the size of a football up in the loft and we could hear the noise in the bedroom underneath.  I had to pay a bloke from the council around £50 to come out and deal with it, after my own attempt to puff insecticide powder in the hole resulted in my getting multiple stings (no fun when your up a ladder).

 

This time I did a bit of digging around on the web and came across this gadget: http://waspnestkiller.co.uk/acatalog/Dustick-High-Reach-Dust-Powder-Applicator-dustick.html for close on £200.  Looking at it in use (there are Youtube videos of people using it) it seemed ideal, as you can stay on the ground and just poke the nozzle in the hole and pump in insecticide powder.

 

I wasn't going to pay £200, so last night I went and had a look to see what I had lying around.  I found a length of 1 1/4" solvent waste pipe, an 1 1/4" solvent straight joiner and a screw on solvent end cap.  I also had some 50mm diameter grey PVC bar, some 6mm brass pipe, a length of 25mm PVC pressure pipe (20mm bore), a very low blow off pressure fuel-type non-return valve and a Schrader valve with a 1/8" BSP thread on it.  All the parts were glued together with ordinary pipe solvent cement, which works just as well on the bits of PVC that I turned up.

 

So, this is roughly what I made up.  First the drawing of the two ends:

 

 

The way this works is that you unscrew the top with the brass pipe, and fill the bit of waste pipe with insecticide powder.  This doesn't need to me marketed as wasp killer (I found it hard to buy wasp killer powder in the local garden centre) it just needs to be a powder containing around 1% or so permethrin.  Ant powder is usually the cheapest way to buy the stuff, and it works very well against any form of insect (including beneficial ones, like bees, so use it with caution).  With the top part full of powder you can screw the lid with the brass tube on, as shown in the photos before (taken after use):

 

 

 

When assembled, the whole thing looks like this:

 

 

It could be made a lot longer, but our house is a bungalow so I cut the 25mm pipe down to make it easier to handle.  The non-return valve in the base of the upper section just stops powder going down the 25mm pipe - not sure whether this was needed, I think I could probably have got away without the bit of 1 1/4" waste pipe, but it is easier to pour powder into the larger opening.

 

Finally this is a close up of the Schrader valve at the lower end:

 

 

To use this I connected a tyre inflater to the Schrader valve, that was connected to my compressor (at around 90 psi).  The brass nozzle was poked into the hole where the wasps were coming in and out and the air trigger quickly pulled to blow almost the entire contents of the powder container neatly into where their next was.  I then beat a hasty retreat, as permethrin tends to get wasps a bit mad for a few minutes, before they snuff it.  I went out half an hour later and there was no sign of wasps at all, other than some dead ones on the ground.  Best of all, there was very little sign of white powder when I'd sprayed the stuff in, as unlike the puffer bottles, this gadget squirts a high velocity narrow stream of dust directly into any hole.

 

The only thing I had to buy was a bottle of ant killer powder for around £2.50, and I only used around half of it.  The rest was made from "may come in handy bits", plus the use of my small bench lathe.  It took me less than an hour to make - the longest bit was waiting a couple of hours to make sure the solvent cement had gone off, before I could have a go at using it.

 

If anyone wants to borrow it they are welcome.  I think it would work every bit as well with something like a bicycle track pump as a compressor, as it doesn't need a lot of air (a 1 second burst was about all it took to empty the container).

 

[ProDave]

Last time I had this problem was in the bay window roof of our 1930's house, a little bit of roof with no access to the void. So wrapped up in motorcycle gear and helmet with all the joints taped up, I took some roof tiles off and emptied a cans of RAID into the roof void.  When the buzzing had died down somewhat, I went up again and poked the nest with a stick to puncture it and retreated.  Again when the buzzing had died down I emptied the second can of RAID into the roof void, and that finished them off.

[joe90]

I had wasps going into a small hole in a wall, presumed a nest was being made in the cavity, I sealed the hole with silicone, stopped them going in or out (plus the ones stuck in the silicone). Seemed to work. I really like Jeremy,s device, I also would rather make something rather than buy it (to my wife’s annoyance sometimes ?).

[Jeremy Harris]

I went up in the loft and couldn't find the nest, so am guessing it was down under the insulation right in the far corner.  I wasn't prepared to lift the insulation to find out, after my last experience, as it would have taken me a fair time to try and escape.  It was also bloody hot up there.

 

This is the hole they were getting in through, with the point where I injected the powder ringed.  The rest of the powder around has blown out of gaps at the edge of the fascia/soffit:

 

[ProDave]

SWMBO noticed we had a wasp nest yesterday, very similar situation on the garage soffit.  I can't think there is much space inside where they were making the nest.

 

I dealt with it with the "squirt and run" technique.  A quick squirt of Raid in the hole then leg it inside.  The first squirt just had the effect of stopping the returning wasps going in, and for a while there were a lot just milling about outside. Each time I noticed there were not many about I went and gave another squirt then retreated.  Something like 6 squirts and a couple of hours later there were none to be seen, so one last good squirt right into the hole just to be sure.

[Bitpipe]

On 11/07/2018 at 09:11, JSHarris said:

...  so last night I went and had a look to see what I had lying around. 

 

Is it just me that goes and makes a cup of tea and settles down to see what Jeremy has now found in his shed / garage?

 

I think there is a TV series here....

[joe90]

10 hours ago, Bitpipe said:

 

Is it just me that goes and makes a cup of tea and settles down to see what Jeremy has now found in his shed / garage?

 

I think there is a TV series here....

 

Well he was on a tv Show, scrapheap challenge. I too love making stuff in my workshop but Jeremy is up there with the gods . Bring it on.

[Ferdinand]

Feeling a bit poorer today, as I have had the roofers in this week for several jobs.

 

Anyhoo, he has found a wasps’ nest. In the most awkward place I can imagine.

 

Here is a pic or two. The entry point is under the flashing right at the back of the rhs small gutter of the dormer, where it meets the hipped roof.

 

The distance from head height standing on the neighbour side of the fence is 5.5m.

 

We have no access from the inside without cutting holes in the bathroom.

 

Suggestions welcome.

 

 

 

 

 

 

 

[Triassic]

Just seal the hole, nature will do the rest!

[Ferdinand]

3 minutes ago, Triassic said:

Just seal the hole, nature will do the rest!

 

What would I seal that with? Low expansion foam?

[Triassic]

If it’s hole, low expansion foam. 

[Jeremy Harris]

I was warned never to ever seal the entrance hole to a nest, last time I paid to get a chap in to deal with a nest that was in the roof space above the corner of our bedroom.  Apparently the trapped wasps have been known to chew an escape hole through a plasterboard ceiling, and fill the room beneath with thousands of angry wasps...

 

Injecting powder in the entrance hole seems to work 100%.  I've now treated four nests this summer, three at our old house and one at the new house.  It seems to be the year for wasp nests in houses, as we've only ever had one before, and that was several years ago (and was when the chap advised me never to seal any entrance hole up).

[Triassic]

56 minutes ago, JSHarris said:

Apparently the trapped wasps have been known to chew an escape hole through a plasterboard ceiling, and fill the room beneath with thousands of angry wasps...

Wow, up here the nests are small, usually golf ball sized at most.

[ProDave]

Ar this time of year I would just leave it, they will be gone soon.

[Jeremy Harris]

26 minutes ago, Triassic said:

Wow, up here the nests are small, usually golf ball sized at most.

 

 

The one in the corner above our bedroom is still there, as wasps never come back to an old nest, apparently.  At a guess I'd say it's close to the size of a football, around 10" to 12" in diameter or so.  The only entrance was through a small gap in the soffit, and they had made a "paper" tunnel to the nest itself, that was built around one of the roof trusses.  The wasp man went up in the loft to look at it and beat a hasty retreat, saying that it we should keep the loft hatch closed for several days and he'd treat the nest from the entrance hole.

 

He used a device that looked very like a modified garden sprayer, one of the pump up things, filled with permethrin powder.  He put on what looked like bee keepers garb and just went up a ladder and puffed the powder into the entrance hole.  He reckoned there would have been several thousand wasps using the nest, and recommended that the best time to treat them was early morning or late evening, when they tend to be less active.

 

The device I made has been used so much that I've improved it, by adding a spring loaded lever air valve at the base, rather than the Schrader valve and fitting a long length of crimped on air line to it, with a quick release connector that fits my compressor.  This makes it a lot easier to use, as I can now control the flow of powder into a narrow nest entrance a lot more easily.

 

 

[Gone West]

14 hours ago, Triassic said:

Wow, up here the nests are small, usually golf ball sized at most.

Yes we found a lot of those in the roof when we were demolishing the bungalow. I don't know what made them but it wasn't the common wasp.