Thread cutting 3/4" galvanised tube

[polygonum_on_google]

I am thinking about making some things for my workshop. In among them, I shall need some fairly stiff metal - probably tube.

Trouble is, cost of P&P makes online prices quite high. I can get suitable tube locally at a reasonable price and avoid P&P but, so far, have not found anyone to supply threaded both ends tube.

I've never threaded 3/4" galvanised so have little appreciation of how tough it is. Nor have I found a pair of die and die stock that obviously go together!

Yes, I have seen sets of tools (e.g. 1/2",3/4", 1" and 1 1/4") but they are far more in terms both of bits and cost than I need.

Is it easy or hard?

[Roger Hayter]

No personal experience, but I've seen the council do 2" railings, and it involves a somewhat large and wide tripod and a consideral effort on a

3' lever (metric versions are available), so I don't think it will work very well without hiring dedicated kit.

[nothanks]

Many many many years ago I "helped" my dad instal galvanised pipework, from 3/4 up to about 3". Perfectly do-able but it requires elbow grease, a pipe vice, cutting oil, and (obviously) a threading tool (seem to be available for less than £50). Alternatively, could you use Dexion tubing, with the knock-in joints? As an aside, for cutting I now use a Rage cut-off saw, bought from the manufacturer as re-furb'ed. It's brilliant and far better than an angle grinder or a hacksaw.

[spuorgelgoog]

If 20mm or 25mm steel electrical conduit is stiff enough, Conlock?

Heavier than that is Kee Klamp.

Or find someone who does gas meter fitting and is used to working with gas barrel.

You can also hire electric pipe and conduit threaders

Owain

[polygonum_on_google]

Having seen lots of thread pipe, I didn't expect any difficulty in getting some locally!

I have rather based my ideas on "cheap" steel pipe. And cheap is highly desirable! Also, a lot easier to make a round hole than a square one.

[polygonum_on_google]

I think holding the pipe won't be too bad - I have garage space and a workbench with vices. But turning (and doing the whole thing reasonably accurately) concerned me. Thanks.

[Fredxx]

You would need a die set and a pipe vice. The question is how often you might use them. I bought a set and have only used them a couple of times. For big ODs they are hard work. I think for 3/4" it should be quite doable.

Ebay sellers do offer pipe with both ends threaded. Perhaps for a small consideration you might be able to get them to thread the parts for you.

It is more typical to use box to fabricate anything and weld. How much strength is required?

the idea at least.

Without knowing why you need to make a hole through anything I'm not sure how to help.

[newshound]

Tend to agree. I think you *will* need a pipe vice.

Also plus 1 for the cut-off saw, except that mine is an Evolution with the multi-material blade.

[Alan]

Easy. Electrical conduit is 20 or 25mm, both are easy enough to bend and thread if you use a pipe vice. And, they also come threaded already at one end, so it shouldnt be too difficult threading the other end. Few plumbers will have dies for 3/4" pipe, but quite a lot of electricians will have dies for 25mm pipe, so maybe rethink it and go for

20/25mm pipe?

[Dave Plowman (News)]

I've threaded 1/2" conduit in the past. Quite hard work even with the correct tools. I'd guess 3/4" even harder.

[harry]

The larger dies are adjustable ie the cutting parts move in and out radially

So the cut is done in several "bites". Perfectly easy up to about 4" It also means that one die set covers a range of pipe sizes.

Tool hire shops is your best bet. You will need a pipe vice and thread cutting lubricant as well. You won't hold the pipe in a normal vice.

[polygonum_on_google]

Thanks - that is an expensive hire!

[polygonum_on_google]

I'll keep that for the future - I have got a decent angle grinder for now.

[polygonum_on_google]

I've gone through eBay and no-one was offering both ends threaded at the length I need - at the moment I checked.

Yes to right length. Yes - to threaded both ends. P&P adds an awful lot - hence my intention of buying locally. But I have started to contact some sellers for quotes.

I'd probably only use the die a few times - currently I can see eight ends. If successful, I might well go further but it would only be a handful each time.

[polygonum_on_google]

Not anticipating a problem with buying threaded, I have already acquired some parts. And the stiffness is very desirable.

But I shall consider dropping down to 20 or 25mm. Thanks.

[nightjar]

I ran an air supply through two factories using 2" and 1" galvanised pipe. Very simple using a hired electric die stock. Just make sure you have planned and cut everything you need first. The daily hire rate is not cheap and, if you have a lot to do, you don't want to waste time cutting pieces when you could be threading them.

[Harry Bloomfield, Esq.]

20mm galv conduit and it easy to put a thread on it. Not sure what you intend using it for, so difficult to determine what it should screw into.

[nothanks]

Yes, mine was called an "Evolution RAGE2 355mm Multipurpose Cut off Saw, B Grade" - I have an ancient Rapidor powered hacksaw which hasn't been used since the Rage/Evolution arrived.

[Andrew]

Which unfortunately will knacker the galvanising at the point where the pipe vice grips the pipe. If your workshop is dry just use 3/4 gas pipe instead ?.

[Tricky Dicky]

+1

You have not made it clear what you intend to use the conduit for, but other than electrical fittings it hard to see what you would screw the conduit into. For most electrical work they are screwed into conduit boxes or couplers, there is a very limited number of other fittings a few which could possibly be used for construction purpose such as inspection bends and inspection tees but these are rather expensive.

Richard