Time for another project ... need to put a 90 degree bend in some
1.25" square section tube.
Not bought the section yet but guessing something like 16 gauge
(0.064") or maybe I will need 14 gauge (0.08")
Obviously the bend radius will mean a reasonably gentle bend.

I have 2 questions if anybody has experience of such things.

# What is the minimum bend radius, I'll make sure I keep above this.

# Is this a practical bend to do at home ... or should I go to a
fabricator and buy it 'bent'

If you are interested the project is:
http://www.eharder.com/Nova%20II/Trailer/Guide-on.html

"Osprey" wrote in message
...
Time for another project ... need to put a 90 degree bend in some
1.25" square section tube.
Not bought the section yet but guessing something like 16 gauge
(0.064") or maybe I will need 14 gauge (0.08")
Obviously the bend radius will mean a reasonably gentle bend.

I have 2 questions if anybody has experience of such things.

# What is the minimum bend radius, I'll make sure I keep above this.

# Is this a practical bend to do at home ... or should I go to a
fabricator and buy it 'bent'

If you are interested the project is:
http://www.eharder.com/Nova%20II/Trailer/Guide-on.html


http://tinyurl.com/ph6bre
=
http://www.thefabricator.com/TubePip...icle.cfm?ID=23

http://tinyurl.com/p7h7by
=
http://www.google.co.uk/search?hl=en...ta=&a q=f&oq=

I would Cut and Shut.

Baz

On Wed, 27 May 2009 03:48:31 -0700, Osprey wrote:

Time for another project ... need to put a 90 degree bend in some 1.25"
square section tube.
Not bought the section yet but guessing something like 16 gauge (0.064")
or maybe I will need 14 gauge (0.08") Obviously the bend radius will
mean
a reasonably gentle bend.

I have 2 questions if anybody has experience of such things.

# What is the minimum bend radius, I'll make sure I keep above this.

# Is this a practical bend to do at home ... or should I go to a
fabricator and buy it 'bent'

If you are interested the project is:
http://www.eharder.com/Nova%20II/Trailer/Guide-on.html

=========================================

I don't think you'll be able to do such a bend at home as it requires a
fairly specialised (and expensive) mandrel and a heavy duty bender. If a
curved bend isn't actually necessary it would be far easier to cut the
tube and weld it up. There are different ways to do this but the easiest
method would be to cut out a 90 degree triangle and bend the tube to close
the resulting gap before welding it up. This method would probably be
stronger than the bend shown in your pictures, if that is an issue.

A radiused bend can be achieved by a similar method to that described
above by making several cuts in the tube before bending and welding, but
the result can look a bit clumsy.

Cic.
--
==========================================
Using Ubuntu Linux
Windows shown the door
==========================================

In article
,
Osprey wrote:
Time for another project ... need to put a 90 degree bend in some
1.25" square section tube.
Not bought the section yet but guessing something like 16 gauge
(0.064") or maybe I will need 14 gauge (0.08")
Obviously the bend radius will mean a reasonably gentle bend.

I have 2 questions if anybody has experience of such things.

# What is the minimum bend radius, I'll make sure I keep above this.

# Is this a practical bend to do at home ... or should I go to a
fabricator and buy it 'bent'

Fill it with fine sand and plug the ends - one first, obviously. Heat to
red and bend. In theory. But probably easier to find a place that has a
bender for this.

--
*Pride is what we have. Vanity is what others have.

Dave Plowman London SW
To e-mail, change noise into sound.

Dave Plowman (News) wrote:
In article
,
Osprey wrote:
Time for another project ... need to put a 90 degree bend in some
1.25" square section tube.
Not bought the section yet but guessing something like 16 gauge
(0.064") or maybe I will need 14 gauge (0.08")
Obviously the bend radius will mean a reasonably gentle bend.

I have 2 questions if anybody has experience of such things.

# What is the minimum bend radius, I'll make sure I keep above this.

# Is this a practical bend to do at home ... or should I go to a
fabricator and buy it 'bent'

Fill it with fine sand and plug the ends - one first, obviously. Heat to
red and bend. In theory. But probably easier to find a place that has a
bender for this.

yes..something like that, or bend round a pretty large radius using a
few tons..like run it over with an articulated lorry on a gravel bed to
start it off...:-)

On Wed, 27 May 2009 13:10:47 +0100, The Natural Philosopher wrote:

Dave Plowman (News) wrote:
In article
,
Osprey wrote:
Time for another project ... need to put a 90 degree bend in some 1.25"
square section tube.
Not bought the section yet but guessing something like 16 gauge
(0.064") or maybe I will need 14 gauge (0.08") Obviously the bend
radius will mean a reasonably gentle bend.

I have 2 questions if anybody has experience of such things.

# What is the minimum bend radius, I'll make sure I keep above this.

# Is this a practical bend to do at home ... or should I go to a
fabricator and buy it 'bent'

Fill it with fine sand and plug the ends - one first, obviously. Heat to
red and bend. In theory. But probably easier to find a place that has a
bender for this.

yes..something like that, or bend round a pretty large radius using a few
tons..like run it over with an articulated lorry on a gravel bed to start
it off...:-)

==========================================

These methods might be worth a try but be prepared for failure. A mandrel
for bending square tube has a projecting rib on the face of the curved
mandrel to push the centre of the tube face inwards. This relieves the
squashing effect on the two sides and helps to make a clean bend. You
might be able to replicate this effect with a cold chisel before trying
the 'heat and sandfill' method, but it seems a lot of effort if a radiused
bend isn't essential.

Cic.
--
==========================================
Using Ubuntu Linux
Windows shown the door
==========================================

On 27 May, 11:48, Osprey wrote:
Time for another project ... need to put a 90 degree bend in some
1.25" square section tube.

Not a hope, even if you fill it beforehand. It will crimp (it has to -
can't do it with pure stretch). So either indent it, notch it, or join
it.

Indenting is pretty strong and simple on a production line (look at a
lot of office furniture) but hard to do neatly as a one-off. You
crumple the inner surface deliberately, thus providing somewhere for
the excess steel to fold up fairly neatly. The outer circumference
remains pretty constant, i.e. no stretching required, so you don't
need tooling that has enough grip to exert a longitudinal tension.

Notching (Wikipedia describes) is how I'd generally do it in my
workshop, but then I'd MIG weld it back together afterwards.

Joining it is simple cut & shut, perhaps even with a plastic plug
joiner in there afterwards. Dead simple, only tool is a hacksaw (or
for Doctor Drivel, a pipe cutter) but the result's not so strong.

"Dave Plowman (News)" wrote in message
...


Fill it with fine sand and plug the ends - one first, obviously. Heat to
red and bend. In theory. But probably easier to find a place that has a
bender for this.




I thought of this ... have bent many a copper pipe that way.

It's looking like I need to find a shop that will do it.

"Andy Dingley" wrote in message
news:876d0195-ac79-4356-8653-

Joining it is simple cut & shut, perhaps even with a plastic plug
joiner in there afterwards. Dead simple, only tool is a hacksaw (or
for Doctor Drivel, a pipe cutter) but the result's not so strong.


I would prefer to end up with a proper radiused bend for appearance sake.

Maybe I should start looking for something that already has square section
with a bend in it, and help it to become a scrap item :-)

10 brownie points if anybody can think of something in 1.25" steel square
section that has a 90 degree bend ...

On 27 May, 14:51, "Rick Hughes" wrote:

I would prefer to end up with a proper radiused bend for appearance sake.

Cut, shut, grind a radius onto the outer face, weld a strip over it.

"Osprey" wrote in message
...
Time for another project ... need to put a 90 degree bend in some
1.25" square section tube.
Not bought the section yet but guessing something like 16 gauge
(0.064") or maybe I will need 14 gauge (0.08")
Obviously the bend radius will mean a reasonably gentle bend.

I have 2 questions if anybody has experience of such things.

# What is the minimum bend radius, I'll make sure I keep above this.

# Is this a practical bend to do at home ... or should I go to a
fabricator and buy it 'bent'

If you are interested the project is:
http://www.eharder.com/Nova%20II/Trailer/Guide-on.html



OK ... this looks like i should get someone to do this for me on a proper
ribbed mandrel.

Does anyone know of any 'on line' sources for engineering firms that will do
such small orders ? only need 2 pieces...... or I'll have to trawl around
local companies.

"Rick Hughes" wrote in message
...

"Osprey" wrote in message
...
Time for another project ... need to put a 90 degree bend in some
1.25" square section tube.
Not bought the section yet but guessing something like 16 gauge
(0.064") or maybe I will need 14 gauge (0.08")
Obviously the bend radius will mean a reasonably gentle bend.

I have 2 questions if anybody has experience of such things.

# What is the minimum bend radius, I'll make sure I keep above this.

# Is this a practical bend to do at home ... or should I go to a
fabricator and buy it 'bent'

If you are interested the project is:
http://www.eharder.com/Nova%20II/Trailer/Guide-on.html



OK ... this looks like i should get someone to do this for me on a proper
ribbed mandrel.

Does anyone know of any 'on line' sources for engineering firms that will
do such small orders ? only need 2 pieces...... or I'll have to trawl
around local companies.

Try these. http://www.technicaltubes.com/ I have used them in the past. Baz

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember Osprey
saying something like:

Time for another project ... need to put a 90 degree bend in some
1.25" square section tube.

An utter ******* to do at home - when made, that would have had a jig
and plenty heat.
I would weld a braced joint.