| From : |
Viv Collins |
| Date : |
2003-07-30 06:19:13 |
| Subject : |
Re:Radial webs |
Hi Gary.
The more folds the better mate as it cuts down the size of the dead spaces at the fold boundarys.
Viv
Gary Robinson wrote :
>Most expansion chambers on 2 stroke bikes are pressed half shells with flange. They are simply aligned, clamped and welding is quite easy as Larry said unless you are uncatious enough to blow a hole, but this method reduces that chance a lot.
>I was thinking of adding some ribs along my next 5.25 Bruno. I could build it out of S/S and be done with, but mild is cheap and easy and I want to try a few ideas along the way. So disposable models at a much reduced cost arent such a bad thing.
>Actually, last time I was at the metal shop we spoke of folding a tailpipe in 2 sections (half shell style) with a flange in 0.9 mild steel.
>Quick, easy Yes.
>Stronger? Maybe.
>
>So this poses another question. Would a pipe folded 8 sided (octagon) be any different in performance acoustically & wave wise? Odd and even numbers sometimes mean black or white. Obviously the more folds the better (360;-) as it would make it 'rounder', but sheet metal folders have limits too.
>I wonder...
>
>Viv Collins wrote :
>
>>Larry Cottrill wrote :
>>
>>>Bruno Ogorelec wrote :
>>>
>>>>Nick Ibbitson wrote :
>>>>
>>>>>the type of welding I do is just a result of finding what works for me, an amatuer and i would recommend it to anyone starting out , it is, i understand a recognized type of welding by professionals but perhaps not used so much as it invelves the time used to form the flange edges
>>>>----------
>>>>
>>>>What I like about it is that it gives you radial dimensional stability. The resulting webs will strengthen the engine enormously. Look at the 'real' Lockwoods and the SNECMA Escopette and you will see such reinforcements used by the big boys. I can't forget Gary Robinson's incredible imploding Lockwoods. A web of this kind would surely have prevented his engines going flat.
>>>>
>>>Bruno
>>>----------
>>>This type of 'melted flange' seam was used for many years in pressure tank welding [don't ask me how they created the flanges]. It is not only useful because of the well-distributed stresses, but because it's so easy to get a seam that is void-free -- no pinholes, etc. Once you get your puddle started, you can go all the way round and complete the weld without filler rod [though on stainless, I still think you'd want a bunch of tiny tack welds to start with].
>>>
>>>L Cottrill
>>----------
>>
>>Larry its a tool called a Jenny, two shaped rollers in a heavy cast frame, it can roll the edge to what ever shape you want just by changing the rollers.
>>
>>We have one as part of the workshop kit but I think its to easy for Nick so he does it with his teeth just to make it a bit more interesting:-)
Viv |
|
Re:Radial webs
( 2003-07-30 06:19:13)