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Discussion Starter · #22 ·
Hi Guys

Making slow progress - my certifier has told me to write it up as a story so I will publish a long update sometime

I have just bought the cells - currently stuck in customs at Auckland

I have a "battery box" intended for a mess of TS cells - 580mm x 930mm
There is space for over 300 Headway 16Ah - and I'm fitting 88!

So what i intend is to space them well apart for cooling - I will also be able to fit a fan for extra cooling if I need it

What do you think - sensible idea?
 

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Hi Guys

Making slow progress - my certifier has told me to write it up as a story so I will publish a long update sometime

I have just bought the cells - currently stuck in customs at Auckland

I have a "battery box" intended for a mess of TS cells - 580mm x 930mm
There is space for over 300 Headway 16Ah - and I'm fitting 88!

So what i intend is to space them well apart for cooling - I will also be able to fit a fan for extra cooling if I need it

What do you think - sensible idea?
Maybe you should space them so that later if you decide to double your cell number you can fit them between the others, so for now, a cell every second or third space?
 

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Discussion Starter · #25 ·
I haven't updated for a long time,

I had expected to get to this point before Xmas but the roll cage caused problems,
The motorsport guys were busy updating their specs and I spent ages waiting for them
eventually I got somebody who new what was required and - a roll cage five months later!

Anyway - the rolling chassis is now on a trailer and I will be taking it to Dunedin on Saturday for its sign-off
Then I will take it all to bits to paint it

Not all lost I made a fiberglass front - not sure about the aesthetics - I will just have to build it and see what it looks like
 

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That is looking good. But why did you put the steering wheel on the wrong side? :D

How is the new left turns before right on a two lane road law going down there? I've driven in Australia and New Zealand, and it is amazing I didn't crash. I didn't get any instructions at the rental car place about that.
 

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Discussion Starter · #27 ·
That is looking good. But why did you put the steering wheel on the wrong side? :D

How is the new left turns before right on a two lane road law going down there? I've driven in Australia and New Zealand, and it is amazing I didn't crash. I didn't get any instructions at the rental car place about that.
Hi Caps

The new rule (same as the rest of the world) has gone down well,
haven't heard of any crashes

I see a bit of hesitancy at intersections sometimes - not a bad thing!

The old New Zealand rule was logical but......
 

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Discussion Starter · #28 · (Edited)
Anyway - the rolling chassis is now on a trailer and I will be taking it to Dunedin on Saturday for its sign-off
Then I will take it all to bits to paint it

Back from the big city - largest city in the Southern Hemisphere!
(not a lot of people but you hit the city limit signs 40 minutes before the actual city)

Passed certification - next stage is the final check-up of a fully assembled car!

Now I have got to take it all apart and paint the bits!
 

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Duncan,

Looking good! In your original post you were concerned with component weight. How are you doing on weight management?

Chuck
 

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Discussion Starter · #30 ·
Hi Salty

I am going to weigh all of the bits again when I strip down for painting,

I had decided that I could get down to 500Kg (from weighing the parts)

But I tried to weigh it one corner at a time (with bathroom scales) and I got 540Kg - with 100kg of bits still to fit

I will weigh all of the bits (bathroom scales) and go and use the local weighbridge and see what I get

650kg is half of the weight of the Subaru but 500Kg would be better
 

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Discussion Starter · #31 ·
Hi Guys
I found this wonderful horn for my car

I will strip the paint and paint it another colour

It has adjustments on the contacts - when I got it it was silent, adjusting the contact up a bit produces a horrible noise (good) and a lot of sparking at the contacts

Does anybody know the correct way to adjust it?

I assume it is 12v as it has a resister in it

Any ideas, help?
 

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I want one!
It looks as if it uses a simple electromagnet and points to make and break the circuit that drives the "speaker" coil. I made a similar device when I was at school to drive an induction coil and produce high-voltage sparks. If it's the same design you can change the vibration frequency by adjusting the pressure on the moving arm. It tends to be a bit hit and miss. They do spark a lot. You could try putting a capacitor from a distributor across the points to suppress the arcing – or just send it to me :)
 

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Hi Woody

Just to be pedantic - true brazing involves a close fitting overlapped joint and the metal flows into the joint'
I am using bronze welding
End of pedantry back to calling it brazing

This is stronger that fusion welding as fusion welding always has a weak zone where the melt pool stops - often a small loss in section as well
Just to be clear.... brazing is not welding. Brazing is generally regarded as a higher temperature process than soldering, but not as high as welding as the filler is drawn in by capillary action and does not alloy (melt) with base metal. The term welding requires the melting of base metal. Bronze welding is a misnomer. There are many design and application specifics that can make brazing a good choice for many designs and often is favoured for thin materials. That said, the choice of filler alloy is obviously of prime importance when applying this process. The other very significant issue is joint design. Typically, an overlap of some kind is used to achieve joint strength due to area for bonding. Butt joints and "T" joints can be problematic depending on service requirements.

Don't get me wrong, as I am not saying your method/process won't work. . I just want to make a few points clear for readers. One cannot say that brazing is stronger than welding . . as a basic statement, this is incorrect. Of course there can be flaws/discontinuities in the application of any joining process.
 

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Does anybody know the correct way to adjust it?

I assume it is 12v as it has a resister in it
Sounds similar to the function of a beetle horn. I don't have the manual on me but IIRC there's just an adjustment screw that set's the 'volume' and it should be set to the lowest reasonable value to keep the heat down.
 

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Hi Guys
I found this wonderful horn for my car

I will strip the paint and paint it another colour

It has adjustments on the contacts - when I got it it was silent, adjusting the contact up a bit produces a horrible noise (good) and a lot of sparking at the contacts

Does anybody know the correct way to adjust it?

I assume it is 12v as it has a resister in it

Any ideas, help?
Not exactly the same, but the 'clear hooter' type horns used on Tigers and other Rootes products are adjusted by their current draw. They're of a similar basic electrical design with a resonator, coil, and contact points, although no resistor. On those horns the upper current limit is 5A and IIRC I adjusted mine for 3 or 4A - and that required ear protection.

Description:
http://www.tigersunited.com/resources/wsm/wsmN27.asp
 

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Discussion Starter · #36 ·
Just to be clear.... brazing is not welding. Brazing is generally regarded as a higher temperature process than soldering, but not as high as welding as the filler is drawn in by capillary action and does not alloy (melt) with base metal. The term welding requires the melting of base metal. Bronze welding is a misnomer. There are many design and application specifics that can make brazing a good choice for many designs and often is favoured for thin materials. That said, the choice of filler alloy is obviously of prime importance when applying this process. The other very significant issue is joint design. Typically, an overlap of some kind is used to achieve joint strength due to area for bonding. Butt joints and "T" joints can be problematic depending on service requirements.

Don't get me wrong, as I am not saying your method/process won't work. . I just want to make a few points clear for readers. One cannot say that brazing is stronger than welding . . as a basic statement, this is incorrect. Of course there can be flaws/discontinuities in the application of any joining process.

But I can - and I'll do it again!

brazing (bronze welding) is stronger than welding (fusion welding) !

And I can back it up

(1) For welding mild steel (as I am)
The filler rod is stronger than the mild steel
You do not get a transition zone in the mild steel (at the edge of the melted area)
Therefore the bronze welded joint is stronger than a fusion welded joint if the fillet is the same size as the material

(2) For welding higher strength steels
The filler rod is weaker than the steel so a bigger fillet is required,
the comments about the transition zone are even more important
Again a good bronze welded joint is stronger


If you fail a correctly designed and manufactured fusion weld it will fail at the edge of the melted zone - careful examination will almost always reveal a necking at this position

A bronze welded joint will normally fail at the parent metal - and I used to have a number of front wishbones demonstrating this
My friend went through so many that I made a good strong metal jig to make replacements - but he was a lot faster than me on the track

The reason bronze welding is no longer widely used is its slooooow and bloody expensive
for my next project I will probably get a MIG/TIG - or possibly one of those newfangled plasma torches
Anybody have any experience with these?


Brazing - proper brazing is an entirely different process - look up bronze welding (that is the correct name)

I believe the Americans have taken to calling it "Braze Welding" - but then they even drive on the wrong side of the road
 

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Discussion Starter · #37 ·
I want one!
It looks as if it uses a simple electromagnet and points to make and break the circuit that drives the "speaker" coil. I made a similar device when I was at school to drive an induction coil and produce high-voltage sparks. If it's the same design you can change the vibration frequency by adjusting the pressure on the moving arm. It tends to be a bit hit and miss. They do spark a lot. You could try putting a capacitor from a distributor across the points to suppress the arcing – or just send it to me :)

Hi MalcomB

I will have to search for an old distributor capacitor -

The auto jumble I got this horn at had several similar units - I paid $5(NZ) about two pounds fifty

Do you want me to pick one up for you if I see one? -
 

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Duncan, I feel your pain.

Bronze welding is a fine, lost art, and still the best technique available for building steel tube structures. Nobody wants to believe it anymore, and too many are willing to criticize without any investigation at all.

I was actually drummed off an ATV board by the local young TIG masters who had no idea what the process they call "some kind of brazing" really was or entailed. People just don't know, and are unwilling to learn, how the finest aircraft and racing cars of a certain era (many of which are still in service) were actually made. The only reason bronze welding isn't used today is its bloody tedious, and takes real skills and patience. But you know all that already...

Keep the faith; stick to your guns, and continue to defend the master fabricators and techniques of a nearly forgotten age.
 

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Do you want me to pick one up for you if I see one? -
Thanks for the kind offer! But I'm going to a couple of big auto jumbles myself this month, so I'll be keeping an eye out for something similar locally. I love the weird and wonderful stuff that shows up, especially at the steam rallies.
 

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In conventional welding where you use a like metal for the filler, you can be somewhat sloppy in your fit-up.
It melts parent metal in with the filler to form a homogeneous mixture in the final weld.


In true brazing, your fit-up is critical to ultimate joint strength, they are usually perfect and almost air tight.
It does not melt the parent metal, but forms a molecular-level bond and the filler is 100% added material.

Brass/bronze will fail in a linear manner where as most other weld types fail in a more abrupt manner.
Like a cannon barrel of old. Bronze canons would split then they failed and cast iron cannons would fragment, killing more crews.


Brazing is rapidly becoming a lost art.

It's chief advantage is it's ability to encapsulate the weldment where other types of welding just sticks things together.
(Yes, it is considered welding.)

Most bronze alloys are rated at 40,000-60,000psi, where as ferric fillers are 60,000-110,000 and more PSI tensile strength.



1950-1960's era British racing cars were fond of this method. Their usage was chiefly due to their easy field repair capability with brazing over anything else then available.

(sorry to run on like that, but my degree is in metallurgy and I dont get a chance to expound on it much.)

Miz
 
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