Cut a hole in plastic tank.

[ChrisR]

Swarf? use a vacuum cleaner or turn it upside down.

But he's ADDING a hole so you can't do either. There will be a couple of inches of water in the bottom of the tank. Some of the swarf sinks, some floats, it's a pain.

Try a sharp flatbit!

Usually the manufacturers can be trusted, but not always. All too often the guy who writes the blurb is a salesman with attitude, who doesn't know much about what he's selling.

 

[JPC]

As it happens , since you mention it i did a 3 yr course..level 2 and 3,,thx You know what assuming does

I made a light hearted remark. and if you went to college to learn your trade you'd remember them saying to use a holesaw...."don't do what all plumbers do and burn a hole with a hot pipe."

Its a lazy and cowboy like practise to burn a hole. it weakens the integrity of the plastic in the area where you have heated it up, which is also where its strained. certain plastics can only be heated up at moulding time....not repeatedly.

saying that i have done it with hot pipe before

noted the spelling thx

 

[crockett]

Use a frikkin holesaw !!! Melting a hole through a plastic tank is supposed to be good professional advise, is it ? And, if this is a diy-er, then when he sets his loft on fire will that just be tough luck ??

Give the proper advise guys, for feks sake

 

[Whitespirit66]

Swarf? use a vacuum cleaner or turn it upside down.

Thanet

Surely the name of the game when working in a loft is to take as FEW tools up there with you.

If, for example I follow Thanet's advice, not only do I need to go out to the van to find my hole saw set and my battery drill and drag them up into the loft, I now need to wrestle the Hoover up there too. Oh, almost forgot, the Hoover needs power, so I have to drag the extension lead up to the loft too. Phew! Then all back down again after.

The hot pipe method only involves using what you have with you already, ie. a torch and some pipe.

I vote - hot pipe method. Works for me!

 

[crockett]

 

[Softus]

But he's ADDING a hole so you can't do either. There will be a couple of inches of water in the bottom of the tank. Some of the swarf sinks, some floats, it's a pain.

I agree that it's a pain, but if I drain a cistern, for whatever reason, I vaccuum it out so that I know that I've left it in a clean state.

Try a sharp flatbit!

I can see that a flatbit would work.

Usually the manufacturers can be trusted, but not always. All too often the guy who writes the blurb is a salesman with attitude, who doesn't know much about what he's selling.

Fair point, but I haven't come any MIs for any plastic cistern that hasn't specifically prohibited cutting a hole using a hot pipe.

Surely the name of the game when working in a loft is to take as FEW tools up there with you.

I disagree. The name of the game is reliability and longevity, not get-out-of-the-house-as-quickly-as-you-can-and-run-away.

If, for example I follow Thanet's advice, not only do I need to go out to the van to find my hole saw set and my battery drill and drag them up into the loft, I now need to wrestle the Hoover up there too. Oh, almost forgot, the Hoover needs power, so I have to drag the extension lead up to the loft too. Phew! Then all back down again after.

Or you could plan ahead.

When you pick up the tank connector, pick up the hole saw (or flat bit) of the matching size, put it in a bucket along with the cordless drill, and the blowtorch (or whatever other pipe jointing tools you're using), and the pipe clips, and the fittings you're going to use, and carry them all up there together. It isn't rocket science, but it does involve using your brain, which you can still do while your knuckles are scraping along the driveway.

 

[ChrisR]

to burn a hole. it weakens the integrity of the plastic in the area where you have heated it up, which is also where its strained. certain plastics can only be heated up at moulding time....not repeatedly.

You're guessing, aren't you!
How does it "weaken the integrity"?? How do you know? Sounds like Bull!

The "certain plastics" you refer to are "thermosets", but tanks are all made of "thermoplastics", which means that if you heat them up, they melt.

The plastics are such poor conductors that only the part right next to your hole would get above normal working temperatures of the tank (they stand boiling water without doing more than going soft..) All the fittings have quite wide flanges so I really don't see any effect at the very edge mattering . The melted swarf which comes from the hole isn't brittle once it has solidified anyway, it's just like the rest of the tank material.
There is a mechanism by which some poor thermoplastics can become brittle if exposed to UV or held at very high temperatures for extended periods, but if wouldn't apply here. (Washing-up bowls left outside, exhibit it.)

There could be a FIRE risk in using a glowing red pipe, perhaps. Maybe that's why they say what they do.
I'm never keen to use a blowlamp in a loft at all.

I agree that it's a pain, but if I drain a cistern, for whatever reason, I vaccuum it out

If I'm just adding an outlet for a shower, I wouldn't fully drain the cistern

 

[Kes]

I use a hot pipe because of the lovely fumes.............. ahhhhh!

 

[namsag]

RE blow lamps being used in lofts and being a hazard could someone please tell me how you are meant to do JOINTS in a loft without one and please don`t say pushfit or compression or even plastic because that is diy cowboy territorty.
As chris has asked please show us evidence that the quickest easiest method of using a hot pipe would damage a plastic tank.
JPC yes we where taught to hot pipe and not hole saw.

 

[JPC]

chris..i'm no clever dick but check google or or wiki it like i did
http://en.wikipedia.org/wiki/Thermal_degradation_of_polymers

namsag...seems you college did not follow the course , nvq?, just checked my level 2 and the book states

"on no account must the hole in the cistern be made by heating a section of pipe"

so the MI, the tutors, numerous websites, nvq books are all wrong then ?

I cant test this..i'm not a chemist...i can only repeat what i have learnt.

 

[Softus]

could someone please tell me how you are meant to do JOINTS in a loft without one and please don`t say pushfit or compression

Push-fit or compression.

If you're making joints onto a pipe from an open-vented cistern then the maximum pressure is about 0.1 bar - hardly a burden for any fitting to withstand.

As chris has asked please show us evidence that the quickest easiest method of using a hot pipe would damage a plastic tank.

The quickest and easiest method is a cordless drill with a correctly sized hole saw or flat bit.

JPC yes we where taught to hot pipe and not hole saw.

Oh well, if you were taught it then it must be correct for ever more.

 

[Softus]

I cant test this..i'm not a chemist...i can only repeat what i have learnt.

And if you do it with your eyes shut and your fingers in your ears then you can call yourself namsag.

 

[crockett]

After you've used your "hot pipe" method, you could then get some blu tack and pritt stick ( I said PRITT) to fix it all together

Seriously, use a holesaw and cordless drill, do the job properly......

 

[namsag]

Thought you said you had put me on ignore softas after you had sexual fantasies about my teenage boy, but if the tablets are working i guess we can start talking again.

And as for comment on pressure of water is it not mains pressure supplying it?

 

[lagunaglen]

Jesus your like a bunch of girls bitching.
Do what suits you best and what works for you .