Bending conduit 20mm crease

[Marvo]

Just saw the later posts, as Pete says sounds like the bend is too tight.

 

[gazdkw82]

think pete has figured it out. It certainly looks the creasing was caused by too tight a bend radius.

However, iv seen tighter bends without creasing. What's the secret to getting a tight 90 degree bend without creasing? heat? bend fast/slow? does it matter? am I too particular? is the prime minister an idiot?

 

[Pete999]

think pete has figured it out. It certainly looks the creasing was caused by too tight a bend radius.

However, iv seen tighter bends without creasing. What's the secret to getting a tight 90 degree bend without creasing? heat? bend fast/slow? does it matter? am I too particular? is the prime minister an idiot?

If I was doing a 90deg bend I wouldn't try and do a tight bend, also I usually take the bend past the 90 and let the tube return on it's only then, would I try and adjust to the correct angle, mind you using cheap tube is a possible cause of crumpling, was the tube 3/4" and the spring 20mm and vice versa?

 

[gazdkw82]

had another look yesterday. Doesn't seem a tight bend. Maybe I just didn't get it warm enough.

 

[Pete999]

had another look yesterday. Doesn't seem a tight bend. Maybe I just didn't get it warm enough.

View attachment 36315

You shouldn't need to warm it that's why it buckled, use a proper bending spring.

 

[gazdkw82]

? I was always taught to create friction/heat with the hand and that helps the tube to bend?

 

[Pete999]

? I was always taught to create friction/heat with the hand and that helps the tube to bend?

Well whoever taught you didn't know diddlysquat about bending plastic conduit.

 

[gazdkw82]

so there is no need to get the conduit warm? that's caused the buckle?

 

[Pete999]

so there is no need to get the conduit warm? that's caused the buckle?

Yep

 

[davesparks]

tge only time I've used heat to bend pvc conduit was to form it round a curved wall.

Normally just put the spring in and bend it round your knee.

 

[Richard Burns]

PVC conduit when cold may shatter, when overheated may well deform as shown in the picture. So long as conduit is at a normal indoor ambient temperature it should be OK to bend with a spring. Though it is possible to get creasing like that with room temperature conduit it would normally be for sharper bends. Some of the videos Pete999 posted with the guy filling them with hot sand certainly looked very over heated as it should not be possible to just wave the conduit around and have it bend if you want a decent curve on it.

 

[Edtwozeronine]

I was also taught to use the friction method and made a fairly nice gradual 90 degree bend as part of my coursework. I technically bent it in 3 places, the middle and about 4" either side of the middle.

I did always wonder if they were extracting the urine with that method though. Anyone got any tartan paint?

 

[Pete999]

I was also taught to use the friction method and made a fairly nice gradual 90 degree bend as part of my coursework. I technically bent it in 3 places, the middle and about 4" either side of the middle.

I did always wonder if they were extracting the urine with that method though. Anyone got any tartan paint?

No but I know where you can get a 3 rung skirting board ladder