Where can I get ?

[DAPPH]

I have a length of 40 mm id x 2.5 mtrs long thin walled stainless steel tube that I want to bend to about 35 % near to one end . I've made a shaped tight fitting 30 mm thickcork block to force down in the tube & have a long batten of wood with a turned up wooden plunger that fits the tube nicely to put in from the longest side to support the cork should it feel like trying to move . it
I have a 12 tonne hydraulic jack type bending press and formers .

Over the last week or so I've done a couple of hundred miles visiting all the builders merchants and roof tilers suppliers in a 15 mile radius to try & get a 10 or 15 kg block of pitch or bitumen to use as a heat up pour in former so I can try and do the bend without rupturing the pipe /tube .
Unfortunately none of these locals have any nor do they know where to get it .


Do any of you guys know of anywhere to obtain some or where I can buy about 4 litres by vloume of it ?

Faiing that ...

Have any of you used anything else as a pour in former on a failry large bore thin walled pipe that can be easily dissolved or melted out. ( I have fire in the form of a large gas fired propane torch , a 2000 PSI power wash and a smallish true steam generator )

I looked at some new lead roll , my scrotum shrank & hid at the £75 plus vat price being displayed for almost the same 4 litre volume
I have plenty of candle wax to try it but feel that he wax will simple part & move outwards inside the tube once it gets a bit of pressure across it .

Any suggestions ?

 

[gaz1]

you mean bitumen block

jewsons sell it

https://www.google.co.uk/search?q=bitumen+block&ie=utf-8&oe=utf-8&gws_rd=cr&ei=qkV7Vv6YEIHyUMiOptAC

just a thought

you could also try the freeze pipe method and there about 7.50 or somewhere around that they form a plug of ice from water

 

[MattH]

I've seen it on the shelf in B&Q but that was a few years back.

 

[Pete.]

Cerrobend is the stuff to use but you wouldn't want to pay for it.

 

[agrimog]

you can do it with filling it with water and freezing it, the trick is add somewashing up liquid to the water, it makes the ice pliable and doesnt shatter when you bend it

 

[Paul G]

Possibly a mix of dry sand and candle wax ?


Never tried it myself as I was once caught stealing the wife's scented candles to mix with soluble oil.
Personally I thought it improved the smell. Apparently not.

Paul G

 

[outofthefire]

Just fill it with kiln dried silver sand, this is three lengths of half inch tube welded at one end filled with sand then twisted up.

 

[Maker]

you can do it with filling it with water and freezing it, the trick is add somewashing up liquid to the water, it makes the ice pliable and doesnt shatter when you bend it

I think I saw that method on how it's made for making brass instruments.

 

[Brad93]

Take it to an exhaust place with a mandrel bender and save yourself a load of time?

 

[I'm getting on a bit]

I think I saw that method on how it's made for making brass instruments.

I saw it too, I think some Harley frames use frozen water process for flaw free Bends as well

 

[DAPPH]

Well , in the early hours of today I did a few searches and found some addresses so at 08.00 this morning I set off , first port of call was 18 miles away .. " Sorry we don't do the 10 , 15 or 20 kg block as the local tilers/roofers won't buy it they only buy 40 Kg blocks price with VAT £ 79 (ish ) ." .................... Eeeek !

Next place some 16 miles further on was a big B&Q .. " Sorry we don't sell it any more , I sold the last block about three weeks ago & it's not going to be re-stocked as it took forever to sell the pallet of it .

Oh well it looks like I've got to try and find an exhause pipe maker or a decent boat yeard etc to get some one else to bend it for me . Not looking foprward to that for last year I asked a company if they would make a stainless steel thing up for me and they wanted £ 75 plus vat for the first half hour , £ 120 plus vat for each hour after that .and that was with me supplying the materials .

As I walked back to the car a guy came up to me fairly fast and said , "I'm glad your on crutches for I'd never have caught up with you if you weren't . I heard the exchange in the store .. I'm the manager of a flat roofing company , we buy the pouring bitumen in 23 kg blocks locally .. Give this card to the lads at this address & you get my discount as I'll phone them to let them know your on the way to pick up a block for me for cash ..... Happy Christmas .!

That brought a bit of a lump to my throat I can tell you .


I went to the place gave the order and the card & ended up paying £21 . The lads there put it in the back of the PHEV for me .

Now the beauty of it all is that once I've done the bending I can reuse the bitumen to fill in some of the slab joints that are in some four year old concrete driveway sections and channel that have had to be cut in two of these sections to to take a 15 amp SWA cable in one & a separate duct/pipe for rain water through it , as the landscapers failed to lay the ducting for it the concrete before they cast the section .. I only discovered that when I returned back form holiday 3 weeks later when the concrete was set solid and nearly cured .

Late this afternoon I slid the block out the car onto our sack barrow wheeled it to the garage door & walloped the block with a 2.5 pound engineers hammer . The top 1/3 shattered into fist sized pieces ...brilliant exactly what I wanted .
I also turned up a bit of 75 x 4 CLS to make a hammer fitting tapered 40 mm plug for the tube.
So unless Santa has other ideas , (For I can't stand the crap on TV that my lass & Munchkin want to put in to their heads ) tomorrow afternoon , after lunch , I just might go fill that tube up with some of the molten bitumen & bend it on Boxing day .

 

[DAPPH]

Just fill it with kiln dried silver sand, this is three lengths of half inch tube welded at one end filled with sand then twisted up.
View attachment 76459

I doubt 40 mm internal dia tube with hard plugged down silver sand in the tube would not collapse or rupture at the welded & polished seam . .( I'll be ensuring that the seam is on the inside or side of the bends where possible
The hard packed dry silver sand in smaller bores , that works up to about an inch quite easily .

Freezing liquids or oils in pipes .. you have to be very careful , lest the liquids expansion ruptures the pipe walls even before you start the bending exercise .

 

[gaz1]

Well , in the early hours of today I did a few searches and found some addresses so at 08.00 this morning I set off , first port of call was 18 miles away .. " Sorry we don't do the 10 , 15 or 20 kg block as the local tilers/roofers won't buy it they only buy 40 Kg blocks price with VAT £ 79 (ish ) ." .................... Eeeek !

Next place some 16 miles further on was a big B&Q .. " Sorry we don't sell it any more , I sold the last block about three weeks ago & it's not going to be re-stocked as it took forever to sell the pallet of it .

As I walked back to the car a guy came up to me fairly fast and said , "I'm glad your on crutches for I'd never have caught up with you if you weren't . I heard the exchange in the store .. I'm the manager of a flat roofing company , we buy the pouring bitumen in 23 kg blocks locally .. Give this card to the lads at this address & you get my discount as I'll phone them to let them know your on the way to pick up a block for me for cash ..... Happy Christmas .!

That brought a bit of a lump to my throat I can tell you .

i would have called you a bloody skinflint if you had of said all that and then said that you hadnt got any all day long and been all over the place

you let lucky damn lucky

as weve always bought the big blocks its how im aware of them

 

[Pete.]

Freezing liquids or oils in pipes .. you have to be very careful , lest the liquids expansion ruptures the pipe walls even before you start the bending exercise .

Not likely with any steel pipe even thin walled. There was a guy who had the idea of taking all the dents out of a vintage outboard motor fuel tank by freezing water inside. He did manage to split the two tanks he had but they were ally and already pretty battered. Got most of the dents out though and once they were split he cut a hole and worked the rest of the dents out before welding it up again.

 

[gaz1]

my advice is dont use it elsewhere unless you got enough of it youve just spent so much time already and you and i both know you will need again somewhere

 

[brokenbiker]

you can do it with filling it with water and freezing it, the trick is add somewashing up liquid to the water, it makes the ice pliable and doesnt shatter when you bend it

This is how brass instruments are bent, saw it being done on trumpets in school

 

[outofthefire]

I doubt 40 mm internal dia tube with hard plugged down silver sand in the tube would not collapse or rupture at the welded & polished seam . .( I'll be ensuring that the seam is on the inside or side of the bends where possible
The hard packed dry silver sand in smaller bores , that works up to about an inch quite easily .

Waste your time on money doing it your way then, the number of times I've been told you can't do something by someone who's never actually tried including twisting tubes together. Once a tube is filled completely it behaves like solid bar.

 

[Chris Stevens]

I doubt 40 mm internal dia tube with hard plugged down silver sand in the tube would not collapse or rupture at the welded & polished seam . .( I'll be ensuring that the seam is on the inside or side of the bends where possible
The hard packed dry silver sand in smaller bores , that works up to about an inch quite easily .

Freezing liquids or oils in pipes .. you have to be very careful , lest the liquids expansion ruptures the pipe walls even before you start the bending exercise .

Bitumen might work, but I would guess whats more likely is this as soon as you try to bend tube: "The top 1/3 shattered into fist sized pieces ...brilliant exactly what I wanted"

I would guess the only way which is sure to work is mandrel bending, which if its for a single bend is going to be a lot less hassle than other methods.

 

[outofthefire]

"I doubt 40 mm"
"Bitumen might work, but I would guess"
"I would guess"

The whole point of coming on a forum is to ask questions to people that know the answer. I gave the answer I've bent steel tube with sand it works those aren't guesses personally I'd bend it hot but I don't have a hydraulic bender like the op has. I did have one but it was more of a pain to use unless you had exactly the correct size of pipe and you were confined to the radius of the die. So I sold it and carried on using sand I've also tried steel shot that works too but it's harder to get hold of than sand. Chris Stevens is right about bitumen though, cold it will crack, folk that use it for reppouse mix other things in with it so it deforms when hit. It also has a natural stickiness which will be a bitch to clean out of the tube.

 

[DAPPH]

Peace on earth and good will to all men stuff guys , don't get in a hissy fit on my account , I asked where I could get the bitumen from .. Iwas given some ideas & 've now got it ...Thanks .

The other tips and advice are gratefully received & may well be used in the future by me or others reading the thread . .

I'll be bending the pipe when it is still full of slightly warm not shatteringly cold bitumen . Once it is how I want it bent I'll melf the bitumen out , I'm not worried if there is a bit of bitumen left coating the pipe wall as it is going to fit on the discharge side of a pond pump that is using a 2,000 psi power washer to drive the suction lift through a venturi. .
I'll bung up some pictures of how it ends up once I've made it and done the road test .

Happy New Year