Water Butt Tap

[Goofy]

I have a large plastic tub (for want of a better word) that I want to use as a water butt. How can I make a hole in it to insert a tap, and what fittings do I need?

[bhg481]

Search for "hole saw". Lots about for a fixed hole-size or ones where you can swap blades for a variety of hole sizes. You won't need high quality for plastic but there's such a large range I'm loath to recommend a particular one.

[Atheist]

I think you should be able to buy a water butt tap, and then you would need to drill a hole in the plastic with an appropriate drill bit.
Is the plastic tub strong enough to hold a weight of water (10 lbs a gallon)?
Is the plastic suitable for drilling? i.e. not hard and brittle plastic.
You should try to obtain or make a lid (not air-tight).
Other ABers may give you more detailed advice.

[theshedman]

Yes as bhg says like the ones in the link below. Just buy the tap first so you know the size you want.

https://www.toolstation.com/holesaw-kit/p23014?store=EQ&utm_source=googleshopping&utm_medium=feed&utm_campaign=googleshoppingfeed&gclid=EAIaIQobChMIq-7QyKyA8AIVT-rtCh1qhg0zEAQYBSABEgK5C_D_BwE

[Goofy]

Thanks. Definately strogenoughh to hold water - it's been standing useless for about 10 years filled with rainwater! Whether too brittle to withstand hole being drilled is another matter. Won't matter much if it collapses!
I'll have a look for hole saws - I think I know someone who might have one. Don't want to spend money tho, and find it doesn't work for whatever reason.

[Goofy]

Just seen post with saw kit. thanks

[bhg481]

That's a good coarse cutter from theshedman - you need a coarse cut and SLOW drill speed for plastic or it melts and gets messy. Another tip, if you get one with interchangeable blades, where the blades are split, make a practice hole first in some scrap wood as the blade can splay a little and produce a slightly larger hole than you are expecting.

[bhg481]

Another thing to bear in mind is that you only get ONE chance to get the size right. Once you've cut the hole your pilot has disappeared so you can only enlarge it with a rasp, not with a different size cutter.

[alavahalf]

If it all goes wrong then cut the butt in half and grow carrots in one half and dwarf beans in the other.
Once you have your hole saw ..
One of these would be good .. https://www.screwfix.com/p/pegler-pb50-hose-union-bib-tap-15mm-x/6263v
Along with a 1/2" back nut with a large flange on it, a rubber washer and a slip washer to suit.
You would drill the hole, insert the tap and place the washer on the back of the tap, then the slip washer and then tighten the nut onto the tap, compressing the rubber washer onto the inside of the butt.
You could easily spend more than £20 doing it if you cant borrow the hole saw. Beware.. as already mentioned .. old plastic tends to have perished and often cracks when you try to mess around with it.

[Togo]

Think I would use one of these to cut a hole in a plastic tub. You need to know the size of the tap thread before you can choose the right size.
Make sure that the drill hasn't got the "hammer" option on if it has one and if you can support the inside at the same time all the better.

Amazon.co.uk User Recommendation

[malagabob]

Cutting a hole in a circular butt is least of your problems. It will be achieving a water tight seal. The mating surface of the tap will be square flat. The butt will at the tap fixing point be concave, albeit slight. A metre of water above the tap will exert a few pounds of pressure.. Is the wall thickness of the but thick enough to achieve a thread. I suppose a tap with a non thread spigot is available. Trail and error sealing around the tap will be the order. A hot glue gun maybe.

[malagabob]

As an after thought. A tap with an extra long thread. With back nut inside and outside sealed between these and tightened up as much as possible.

[Hopkirk]

As an aside, I remember a viciously cold winter a few decades ago, and my Dad's two huge plastic water butts froze solid. We thought they would topple, as the bottoms bulged out with the expansion. We also thought they might split as they ballooned out a bit. However they did eventually thaw and survived.

[bhg481]

I fixed a bog-standard bib tap to one of my water butts with no sealing problems. The hole provided by the manufacturer was occupied by a connecting feed from an adjacent butt, so I drilled a hole and fitted the bib tap. I used a bib tap rather than the usual butt tap because I wanted to be able to connect a hosepipe to it and sealed it with PTFE tape and rubber washers.

[satprof]

It might seem obvious, but don't forget to (more-or-less) empty the tub before drilling, unless you want an involuntary shower. If the tub is too heavy to tip over, siphon off the water to at least a short distance below the projected tap.

[Goofy]

Good Grief!
I thought it would be wasy. Might work out cheaper to buy one.
Thanks all

[Goofy]

Thank you for your advice. Now working and just for the price of a tap (well 2 taps as the first one disappeared, I think the hens knocked it off the shelf and into the rubbish!)