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Re: Rear Stand

Bruce
Are BSA frame lugs malleable iron or steel forgings? I think they are malleable iron but can't prove it.

I know for a fact that Triumph used malleable iron lugs. I had a 1958 Triumph with a broken side stand lug and was told by the person who had been the USA warranty manager for BSA/Triumph in the 1960's that it was malleable iron as I wanted to know what the best way to repair it would be. When Triumph introduced the unit construction 350 / 500 twins, the factory literature states the lugs are malleable iron. As BSA owned Triumph, why would they not use the same materials?

AJS / Matchless used malleable iron as many years ago I read an article in the AJSMOC news letter written by someone who worked in their foundry.

Phil Irving stated in one of his books that Vincent's used malleable iron for the frame.

Norton also used malleable iron as a friend of mine was restoring a International that had frame damage. The company making the new lugs stated they were malleable iron, the same as the factory ones.

In the literature for the Sunbeam S7 twin from 1947, it states the frame has malleable iron lugs. Sunbeam at the time was also owned by BSA.

The only literature I have seen from BSA about forged frame lugs is in regards to the Gold Star. Somewhere around 1956 the front motor mounts were changed to forgings.


So everybody else is using malleable iron and only BSA is using forgings? I wish I had a scrap frame I could cut a piece off of to see what it is made out of?
You can tell just by looking at them although a bare metal finish is better
Forging have sharp defined edged, particularly the part number that is often forged / cast into them
Castings will always have a rounder finish and generally a rougher surface texture as iron & steel is always sand cast
IT is sort of like the visual difference between a sand cast crank case & a die cast crank case
orging dies are smooth, they have to be or the forgings will adhere to them
And yes BSA used both forgings & castings , often for the same part .
Forging dies take weeks to months to machine a pattern for a sand casting takes a good pattern maker a couple of hours
So not uncommon even today to have the initial production run as a forging .
You make all you need for the projected production run of that item
Then the dies get retired or even damaged / worn beyond recovery.
Now you just need enough A 10 frame lugs for another six months production because the A 65 production has been held up .
Thus you do a run of 5,000 castings because you will never recoup the cost of making a new set of forging dies .
These sort of situtions happen all the time
Another example is the arrow head mudguard stays used on the Spitfires
Not worth the cost of making another forging drum so cast the ends & braize them onto strait tube .

Things that clamp are best made as a forging, like the early saddle tube clamp
Where as some thing that is always rigid like the rear fork ends can be done either way

NExt problem is how you are going to join them
You can not weld steel tube into a malleable iron lug but you can furnace braize it

Then there is the availability of the machines
If the forging line is fully committed & running 3 shits and suddenly you need 1000 lugs then they can get cast without too much disruption while forgings would have held up production of some thing else .

Unless you have been involved in manufacture it is difficult to understand all of the complexity of making 1600 ( total guess ) parts & assembling them into a motorcycle that needs to be delivered at a specific date

Re: Rear Stand

MARK COOK
I've just had a kind offer of a damaged one to copy, how much of this bike am I going to have to make? Seeing as it will want jigging I'll runs some extras off at the same time. Sorry it will be lighter than original as I mainly carry 4T45 tubing.
The original stands bend reasonably easily especially if you sit on the bike when its on the stand, so a lighter tube wouldn't be a good idea unless its structurally as strong, I admit I don't know what 4T45 tubing is?

Rob

email (option): robmiller11(a)yahoo.co.uk

Re: Rear Stand

OK I looked it up and its an Aircraft Grade seamless tube, I presume a bit like Reynolds tubing?

Rob

email (option): robmiller11(a)yahoo.co.uk

Re: Rear Stand

I've been using it for a long time Rob, and it does replace some of the reynolds grades.
What I like most is that it doesn't require heat treatment after welding as some of the equivalent grades do.
It joins well with Gas, braise, bronze weld, MIG, and TIG. It tends to undercut with stick welding.
These features made it very popular for aircraft manufacture during WW2 in the uk.

For making anything like this someone a bit heavy handed is good for testing. :)

email (option): pes.sales@btconnect.com

Re: Rear Stand

MARK COOK
I've been using it for a long time Rob, and it does replace some of the reynolds grades.
What I like most is that it doesn't require heat treatment after welding as some of the equivalent grades do.
It joins well with Gas, braise, bronze weld, MIG, and TIG. It tends to undercut with stick welding.
These features made it very popular for aircraft manufacture during WW2 in the uk.

For making anything like this someone a bit heavy handed is good for testing. :)
Hi, don't panic. IT is possible tot bend the tubes for a perfect fit. 💪 I AM sorry but can't show a pic. of mine on the forum 😥
John 🐈

email (option): john.kater@chello.nl

Re: Rear Stand

Mark,
I am sure you are familiar with the tight fisted nature of British bike owners.
Double that for the back yarders who "restore" for profit/.
Thus there is no part so badly made or poorly fitting nor unfit for the end use that s BSA owner will not use it provided that it is cheap enough.

Add that to the conspiracy mongers who "Know" there is a massive stash of NOS parts hidden from them so the retailers can make massive profits by keeping the market in short supply.

The exception to this is of course seriously competative race riders when money is less of an object when winning is what is important.

The backbone of BSA's reputation for quality & longevity was the forge and in particular the use of forged lugs on the frames up to & including the stand lugs.
While malleable iron is a suitable material for lugs, it will vary greatly as the chemical composition of the actual melt changes while pouring let alone different melts.

While modern steels are much more uniform and advances in metallurgy means modern castings are much more consistant , none of them will match the strength & durability of a forging, and that makes manufacturing pattern parts a nightmare as forgings are prohibatively expensive and castings need to be dimensionally heavier.
Rivet counters want parts that look identical, this badly welded rubbish , full of filler that are not fit for purpose .

email (option): bsansw1@tpg.com.au

Re: Rear Stand

Thanks Trevor, wise words as usual.

As they have failed or became too hard to find or even expensive I have replaced forgings/stampings with investment castings very successfully. The trick being in the choice or steel and the heat treatment. The hardest part is forming a working relationship with a foundry and getting them to embrace new or unorthodox ideas. I wish I had your experience of metallurgy and the associated science. I admit using trial and error with many of my new ideas.

I really don't want to get into fabricating manufacture, though we have a comprehensive factory. If I could find suitable staff that might change. If I make one of something there are often others made at the same time. They get put up for sale, if they sell I might make more.
I've just finished a Job costing me over £3000.00ukp in labour. The part produced I'm asking £150.00 I could never break even on it. I just needed one to finish another job. There were alternatives but the result would have been substandard.

email (option): pes.sales@btconnect.com

Re: Rear Stand

I bought one of the M20 stands from Josef and can state that the quality and price was excellent! Glenn

email (option): Glenn_mullan@postmaster.co.uk

Re: Rear Stand

The question of forgings or malleable iron castings has been a long running one...A trawl of the internet turns up comments that definitively state that either one or the other was the type used...Well they can't all be right unless changes took place at some time or other...

My question is does anyone have any BSA literature that specifically states the materials used?...I'd like to be certain about this point...Ian

email (option): ian@wright52.plus.com

Re: Rear Stand

Ok brilliant, thank you I’ll try that one also, noted about time to reply, thanks 👍

email (option): markmayo63@yahoo.co.uk

Re: Rear Stand

This one runs and runs...
I'm in agreement with Bruce that malleable iron castings would have been the standard specification in the vast majority of cases for frames and fittings....The evidence outlined by Bruce points clearly to that being the industry standard...Forging and casting costs aren't even close and the cheapest servicable option was the one most manufacturers went for...
The industries attitude to cost is indicated by cylinder and head castings...Aluminium heads and barrels cool better without a doubt as well as having weight benefits but their use was by no means universal.. In the case of barrels the lighter and better cooling material was chosen even less often than for heads....Cast iron ruled in these general applications for years after aluminium casting techniques were perfected and the reason was cost...Iron castings were cheaper as it was the cheapest engineering material...
BSA didn't operate in a vacuum and though they had far more capability than most motorcycle firms when it came to manufacturing methods the bikes had to sell in the same dealership as the others and had to be competetively priced...
These bikes were mass produced by the standards of the day, particularly during the war and to run such a system successfully requires all the parts to be available all the time at the assembly point....To this end production engineering departments exist to ensure a planned and sufficient supply of components is available....The idea Fred went off from assembly to find an alternative mudguard because they'd run out or that cast/forged/machined parts were produced by some haphazard arrangement that didn't result in a smooth supply of finished parts is frankly, comical...Everything had to work for most of the time with minimum deviation from the production and assembly procedures...I've worked in production (including production engineering) and idle production lines and personnel due to shortages were deemed to be virtually a hanging offence!...Ian

email (option): ian@wright52.plus.com

Re: Rear Stand

Well it did not run smoothly
UK dealers probably did not notice it but down here and in the USA it was not uncommon to have bikes arrived fitted with the wrong parts because the right ones were not available
There are dealers notes covering reimbursements for swapping the wrong ones for the right ones
In the UK was not so important because you could just hold back the delivery a week or even a month but you can not do that if you have bought & prepaid space on a ship .
Then you get things like total failure of things like the Dandy, Beagle , Scooter & trike .
Plus you can only try to predict market sales and the market can buy bikes a lot faster than the factory can make them
BSA could not make 20,000 motorcycles and park them on the sports ground waiting for sales.
Export models were made against actual orders and they were an unknown till they arrived .
I have worked on factory floor for years and seen this happening every day of the week.
More than once I can remember remelting extrusion billet because a new priority order came in that needed a different size billet or the projected sales of a particular billet size never eventuated or even remelting finished casting to make ingot because the casting did not reach the projected sales volume.

Even castings have to be carefully planned, you start a new linning with the least alloyed metal and work towards the highly alloyed.
Should you suddenly have to do a high alloy melt that can throw off the entire life span of that linning and force you to do things like a 100% scrap pour in order to dilute the wash in the furnace back to what you need to make or do a pour out ( completely empty the furnace ) which can delay the next pour for a full day.

There is a limit to the number of people that can be employed in production planning and that job becomes massive when you have a lot of models with few common parts which BSA eventually realized by 1930 was eating into massively into profits thus the Page redesign & rationalization .

Now days with critical path charts and computerise production planning we take these things for granted .
a complete Gant chart even for a WM20 would probably be 3 meters long if not longer

You have been around motorcycles for a very long time
How may times can you remember an artical in the weeky motorcycle press announcing that some new seasons models would be "X" weeks late being delivered into showrooms and that only happens because they had run out of a part.

And while there is a price difference there is also a speed difference and strength difference which of course makes a weight difference

And don't forget that BSA was selling forgings to the push bike industry the whole time , even after they sold the push bike division to Raleigh .
And some times you make a more expensive part as a loss reducer because that machine ( or forge ) has no work so you task it to a part that would normally be made elsewhere because that looses less money than having a furnace ( which can't be turned off ) running or a shit sitting on their butts

My last 6 months at Simms was as production planning and all I was making was secondary foundry ingot .
But making sure I had the right scrap in the yard at the right time to make the projected sales was a full time 10 our a day 5 day a week job.
Now days the computer dose it in real time 5 days in advance , becomes aware if there is a supply problem sources alternatives and can even project further forward if needed say for an export order
Do I also need to remind you of BSA selling barrel steel to the Enfiels works because they did not have enough steel to make the rifles needed at the beginning of WW II , production scheduling failures were very common till the advent of computers .

Then material selection is a very complicated process and back in the days of slide rules it was even harder
BSA knew exactly how thick a iron head needed to be and how many bolts you needd to hold the head on at particular compresson ratios & engine speeds , they knew this mostly by trial & error and a lot of real metal testing and this is very expensive .
They knew how thick a barrel flange needed to be on a particular engine which is why you have thin flange A series twins, thick series barrels then the even thicker Daytona barrel flanges .
Now days Mark can run computer models to determine the limits of reliability but back then it was lots of calculations followed by metal samples made by trades men then tested to destruction which is unbelievably expensive .

How many Gold Stars have been through your workshop with a big split up the alloy barrel that needed to be welded , machined then a new linner fitted, not the job you would be wanting to pay a dealer to do under warranty .

On top of that there is the tooling costs to change materials
Remember the story of the A 3.5 , despite it being substantially cheaper to make than the C series that were already obsolete.
Despite having firm orders for them . BSA revived production of the C10, C11 and then C12 because they had not fully amortised the tooling cost from 1934 .
So what were the chances of the board condoning the cost of changind the barrels on the M20, A 10 even C series to aluminium when they had all the tooling needed to make them in grey iron which they knew worked well .

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