Jon's bent is bent.

Jon Senior said:

Oops. For those that didn't catch it in the other thread
and who are interested in the saga of my recumbent, a new
page has been added at:

www.hoovesofdestiny.co.uk

Enjoy.

Jon

Makes interesting reading - don't get me started with bike
building, I just read Sheldons site about buildng a fixed.
The plans I have for when I get my employment sorted out.

You really ought to paint 'Hooves of Destiny' on the boom
Jon.

On 5/7/04 9:42 pm, in article [email hidden],

Jon Senior' jon_AT_restlesslemon_DOTco_DOT_uk said:

Oops. For those that didn't catch it in the other thread
and who are interested in the saga of my recumbent, a new
page has been added at:

Out of interest, what is the steel you used, and could it be
a heat treatment problem (heat affected zone) from the
welding potentially making the weld material/non HAZ metal
transition vulnerable to tearing.

Would pre/post welding heat treatment help? Any
metallurgists here or should I chat to my Dad (FWeldI,
FIM, FIP FICorr and a few others) before I start to play
with making a similar monster.. (except my welding is
really bad).

..d

David Martin [email hidden] opined the
following...

Quoted message said:

On 5/7/04 9:42 pm, in article
[email hidden], "Jon Senior"

jon_AT_restlesslemon_DOTco_DOT_uk said:

Oops. For those that didn't catch it in the other thread
and who are interested in the saga of my recumbent, a
new page has been added at:

Out of interest, what is the steel you used, and could it
be a heat treatment problem (heat affected zone) from the
welding potentially making the weld material/non HAZ metal
transition vulnerable to tearing.

The steel is standard mild steel. Quite probably. I carried
out no post- weld heat treatment, and do not have the
technology to do so.

Quoted message said:

Would pre/post welding heat treatment help? Any
metallurgists here or should I chat to my Dad (FWeldI,
FIM, FIP FICorr and a few others) before I start to play
with making a similar monster.. (except my welding is
really bad).

I would be very interested to hear any opinions on the
matter. I'm planning a new version of the frame which will
involve a move to a lighter gauge material and would quite
like to be confident in my welding skills first. With regard
to welding skills. I learnt to weld as a part of the project
and my welder is permanently stuck on its highest power
setting. You can't really be starting from a worse point!

Jon

In article <[email hidden]>,
David Martin

Quoted message said:

Would pre/post welding heat treatment help? Any
metallurgists here or should I chat to my Dad (FWeldI,
FIM, FIP FICorr and a few others) before I start to play
with making a similar monster.. (except my welding is
really bad).

I thought that bike frames were brazed? Uses a much lower
temperature than welding.

--
A T (Sandy) Morton on the Bicycle Island In the Global
Village millport.netmillport.netOpen ↗

Sandy Morton [email hidden] opined the following...

Quoted message said:

In article <[email hidden]>,
David Martin

Quoted message said:

Would pre/post welding heat treatment help? Any
metallurgists here or should I chat to my Dad (FWeldI,
FIM, FIP FICorr and a few others) before I start to play
with making a similar monster.. (except my welding is
really bad).

I thought that bike frames were brazed? Uses a much lower
temperature than welding.

Depends. Steel can be (reasonably) easily welded using
standard arc or MIG welding. Brazing gives a greater degree
of control and allows for corrections to be made (The braze
can be melted out and a tube removed or repositioned.
Depending on the alloys of steel however post-braze heat
treatment may still be necessary. I believe that they
principle feature of Reybolds 853 is that heat-treatment is
unnecessary. Brazing also requires close fitting lugs for
optimum performance and certainly a close fitting join is a
minimum requirement.

Aluminium is generally TIG welded for reasons of strength.
It can be stick / MIG welded but these welds tend to be
less reliable and require greater skill. I'm not sure
about brazing.

My frame is made of 2mm mild steel and can be welded quite
happily without too great a fear of problems. This is good
given my obvious lack of skill with a welder!

Jon

On Mon, 05 Jul 2004 23:32:59 +0100, Sandy Morton <[email hidden]>

Quoted message said:

I thought that bike frames were brazed? Uses a much lower
temperature than welding.

Either, but you can only braze a frame if you can get lugs
to suit the joints you want to make, which I imagine to be
less likely with an idiosyncratic recumbent design.

Welded frames go back a fair way - a lot of 1940s/early 50s
framnes were welded because the factories that made the lugs
had converted to munitions production for the duration.

Roger

"Roger Hughes" <[email hidden]> wrote in
message "]news:[email hidden]...

Quoted message said:

Sandy Morton said:

I thought that bike frames were brazed? Uses a much lower
temperature than welding.

Either, but you can only braze a frame if you can get lugs
to suit the joints you want to make, which I imagine to be
less likely with an idiosyncratic recumbent design.

Fillet brazing?

cheers, clive

ps greenspeed certainly used to MIG weld their stuff

Roger Hughes said:

Sandy Morton said:

I thought that bike frames were brazed? Uses a much lower
temperature than welding.

Either, but you can only braze a frame if you can get lugs
to suit the joints you want to make,

Hey hang on...fillet brazing is used extensively and with a
high rate of success by recumbent builders, and particularly
in the high stress areas, like attaching a boom to an
existing headset. What's critical is the 'snugness' of the
butt joint before brazing.

Here are some thoughts by Mark Stonich - a well respected
American homebuilder.

mnhpva.orgbrazing.htmlOpen ↗

and 01120015.JPG shows a simple example from another,
completely unrelated site

snorlax.lampi.orgINDEX.HTMOpen ↗

Garryb [has donor bikes cut, but Mapp gas standing idle...
..for months now :-( ]

Quoted message said:

which I imagine to be less likely with an idiosyncratic
recumbent design.

Welded frames go back a fair way - a lot of 1940s/early 50s
framnes were welded because the factories that made the
lugs had converted to munitions production for the
duration.

Roger

in message <[email hidden]>, Jon Senior

jon_AT_restlesslemon_DOTco_DOT_uk ('') said:

Oops. For those that didn't catch it in the other thread
and who are interested in the saga of my recumbent, a new
page has been added at:

www.hoovesofdestiny.co.uk

I expect part of your problem here is the shape of the
frame. Seriously. The right angles in the fork are points of
high stress. You'd be much stronger if instead of having
parallel fork legs you had them mitred into the main tube
and diverging from it in a very narrow 'Y' shape (I know
this isn't the aesthetic you want, but think about the
stresses). You would also be better off with stock which was
not square in cross section - if it was twice as deep as it
is wide you'd get better strength here. Alternatively you
could weld on a triangular web under the groin of the fork.

Consider that the frame is essentially a beam supported at
the wheel axles and with the load on it mainly on your seat
which is practically over the point of divergence of the
fork. That's where you need maximum strength and it's where
your design has maximum weakness.

--
[email hidden] (Simon Brooke)
jasmine.org.uk~simonOpen ↗

;; For in much wisdom is much grief; and he that
increaseth ;; knowledge increaseth sorrow.." -
Ecclesiastes 1:18

Jon Senior said:

Oops. For those that didn't catch it in the other thread
and who are interested in the saga of my recumbent, a new
page has been added at:

Look on the bright side: all the functionality of a £2,000
"proper" 'bent for a fraction of the price :-)

--
Guy
--
May contain traces of irony. Contents liable to settle after
posting. chapmancentral.co.ukchapmancentral.co.ukOpen ↗

Just zis Guy, you know? [email hidden] opined
the=20 following...

Quoted message said:

Look on the bright side: all the functionality of a
=A32,000 "proper" 'be=

nt

Quoted message said:

for a fraction of the price :-)

I thought about making this comment myself but wasn't sure
if you'd take=20 offense. Obviously not.

Jon

Simon Brooke [email hidden] opined the following...

Quoted message said:

in message <[email hidden]>,

Jon Senior jon_AT_restlesslemon_DOTco_DOT_uk ('') said:

Oops. For those that didn't catch it in the other thread
and who are interested in the saga of my recumbent, a
new page has been added at:

www.hoovesofdestiny.co.uk

I expect part of your problem here is the shape of the
frame. Seriously.

Part? Almost all of!

Quoted message said:

The right angles in the fork are points of high stress.
You'd be much stronger if instead of having parallel fork
legs you had them mitred into the main tube and diverging
from it in a very narrow 'Y' shape (I know this isn't the
aesthetic you want, but think about the stresses).

The square fork was not an aesthetic decision, it was a
practical one. With a reduced time in which to build it
and limited access to any kind of jig it was the simplest
and easiest way to do it. I've started planning version 2
which will not only have a full triangulated rear fork,
but suspension and a larger boom and will thus eliminate
the problem.

Quoted message said:

You would also be better off with stock which was not
square in cross section - if it was twice as deep as it
is wide you'd get better strength here. Alternatively
you could weld on a triangular web under the groin of
the fork.

Consider that the frame is essentially a beam supported at
the wheel axles and with the load on it mainly on your
seat which is practically over the point of divergence of
the fork. That's where you need maximum strength and it's
where your design has maximum weakness.

Agreed. When I built it I was aware that it would be the
weakest point on the bike but the whole frame had been
deliberately over-engineered. What I didn't take into
account was the damage that I could do when trying to tidy /
replace one of my worst welds. The new reinforced joint
should (hopefully) hold until I can get the prices for the
new frame. I've just discovered that an engineering firm
round the corner will weld it for me so they may get some
work to save me making the same mistakes twice.

Jon

Jon Senior <jon_AT_restlesslemon_DOTco_DOT_uk> wrote in
:"]news:[email hidden]:

Quoted message said:

The square fork was not an aesthetic decision, it was a
practical one.

Jon, if you want to go for round tubes you might be
interested in some of the information and software available
from here
<http://www.ihpva.org/people/tstrike/building/tubemit.htm>

The software allows you to print a template for
cutting mitres on tubes of various sizes, thicknesses
and mitre angles.

Graeme

Finally managed to finish rebuilding the bent after work
today. It has survived its first ride home without ominous
creaking noises but has somehow developed an unusual speedo
quirk. It is recording two pulses for each pass of the
magnet (I think) and adjusts my speed accordingly. It is
consistent and claimed a very ego-flattering 25mph for Leith
Walk (Ascent!) despite it being about 5mph more than I
normally manage on the fixer in sprint mode.

Ah well. At least I'm back in the realm of daft equipment
problems not broken frames.

Jon

In article <[email hidden]>, Jon
Senior <jon_AT_restlesslemon_DOTco_DOT_uk> says...

Quoted message said:

Ah well. At least I'm back in the realm of daft equipment
problems not broken frames.

Or daft _user_ problems! The thing about having a computer
with two wheel sizes is remembering to switch between them
when changing bikes!

Jon