Here is a list of all the postings Clive Foster has made in our forums. Click on a thread name to jump to the thread.
|Thread: Triumph motorcycle auction|
Yep. Final stage of offshoring production to Thailand. Main market expansion is expected to be in Asia where UK exports face 30% tarriffs.
Apparently 9,000 sold in Uk, 15,000 in America, 33,000 in Europe and 6,000 in Asia.
Mostly built in Thailand anyway.
Standard bean counter comments about production in low cost countries. Far as I can see they have milked all the value out of appearing to be a British company.
Interesting alternative but I'd stick with 605M36 T from a reputable supplier with a certificate. Inclusion modified for easier machining if I could get it but that would need to be pure luck with an offcut.
Compositions are near as damnit the same but USACUT has a slightly lower maximum permitted sulphur and, generally a touch more manganese and molybdenum. Mostly its going to overlap so you'd probably not notice any difference in practice. Brinell hardness is effectively the same.
What would worry me for spindle use is that USACUT55 elongation in T condition is given as 8% and Izod Impact 34 whilst the figures I have 605M36 T has an elongation of around 11% and Izod impact around 74. Izod tends to be rather variable, ± 5 or so for 605M36 T from the figures I have. The lower Elongation and Izod figures for USACUT55 suggest it may be more brittle and crack prone in T condition. Which would make it easier to machine. Its the tough, ductile, stringy stuff that brings out the curses. Yes Mr Pure Aluminium I'm talking about you.
Whether this actually matters in practice, strong enough is strong enough after all, I don't have the detail engineering knowledge to evaluate. But I have seen a cracked, fortunately not broken, front wheel spindle so its an area where I really am going to listen to a man who is proven expert. I have no knowledge of the history of the cracked spindle in question. Best guess is that it got bent in a crash and some penny pinching oik tried to hammer it (not quite) straight but I don't know if it happened in service. Auto-jumble purchase I was asked about repairing. Er Nope! Think it was £7 odd from the jumble when NOS factory could be found for £15! Some people.
Reliable friend tells me that local bike MOT place refused to let a customer take a Harley engine in Norton featherbed frame special away. Front wheel bearing bores were too large for the spindle so the wheel was jumping around. And the man rode it down there for its first MOT in his hands having paid £ "lots" for it.
USACUT55 is probably a fairly academic choice as it only seems to be available in full bars. 3.5 metres will make a lot of spindles.
Titanium is for the guys who know what they are about. Even harder to machine than stainless if you don't know the tricks, I don't really, and even easier to buy the wrong thing.
|Thread: Using the Maplin (Dremel clone) for cutting tool steel|
The power supply for the Maplin appears to be in the grinder itself, not a separate unit. On the separate supply ones the power unit runs all the time its switched on. The switch on the grinder just handles the low voltage supply to the speed control and motor.
If your power supply is integrated into the main body and arranged the same the power supply will be running all the time the mains supply is turned on so it will get warm even when not using the grinder. Its arguable that such is a good way of doing things but I'm not completely convinced. Suppose it it would make it harder to switch the grinder on at the mains and have it start running immediately.
All these multi-tools are made to take light side loads on the bearings. The operative word being light. Generally the higher end makes will put up with a heavier light than the cheapies. But appropriate care is needed. As I don't need one much I bought cheap (LiDL) and consider it disposable.
Edited By Clive Foster on 07/08/2020 18:54:13
Glad you liked it.
As I said the major issue is that folk like us are supply constrained. Not so much a matter of getting the absolute best material more a case of being sure that we have got a suitable piece of material in the right condition and properly heat treated for a safety critical job.
For something like a spindle I'd never order against an EN number.
Had a couple of 1 foot lengths of EN something a fair few years back from one of our suppliers with well deserved reputation for being both good and reliable that were actually last 14 inches of one bar and first 14 inches of another, or thereabouts. So I got a bit of a bonus. They machined rather differently so obviously not the same. Quick check back with the supplier showed that they were from different stockholders. As it was a very uncritical application, "needs a bit of steel this size" sort of thing, I'd not have bothered except that some parts needed to be welded so I wanted to be sure an error hadn't been made with one length being unsuitable for welding. Apparently I wasn't the first person to notice such variations.
Another time I needed 4 lengths of modern "number-letter-number" designated steel almost immediately. Local guy I liked to use for pick-ups only had one length of what I wanted but as the designation overlapped an EN number he offered to make up with the last 3 bars in the rack of what he was supplying for that EN. On a 4 for 3 pick up this afternoon deal so I bit. All machined differently, all up for the job (could easily have ordered EN but had got into the habit of going all modern with that guy and doing it right) so I worried not except that one end of one bar was harder than a woodpeckers beak. Ripped the tip straight off a tool. Angle grinder took the first 4" off as a sacrifice and the rest machined fine but clearly harder tha the others. I'm darn sure I got something a lot better than I paid for!
Most of the time there are no issues but do you want to risk being Mr Unlucky?
Edited By Clive Foster on 07/08/2020 18:39:50
John Bradleys' 3 books "The Racing Motorcycle, A technical Guide for Constructors." are the bible for advice on this sort of thing. Volume 2 covering chassis materials & construction techniques is superb guide to materials and their appropriate use even if you have no intention of building a bike. Hopefully it will be back in print sometime. He is a professional engineer who has built his own racing bikes from scratch (all bar the engine) in a home workshop and remains a well respected consultant to race teams on suspension and set-up matters.
An all round nice man too.
John says :-
"I really like 605M36 T (EN16T) and use it in the T condition for virtually all spindles that do not involve individual heat treatment. It is widely available in this condition and may also be inclusion modified for easy machining.
This is a manganese-molybdenum steel with excellent toughness and shock resistance at normal temepratures. 605M36 is much less suceptible to temper brittleness than the chromium based alloys. 605M36 can easily reach T condition in our sort of sizes and only much larger sizes (eg 60 mm diameter and above) will be offered in the lower ranges such as R or S. I have used 605M36 T for 35 years and it has alaways been a trouble free option."
"709M40 T (EN19T) is a very popular chrome-moly steel which is again available off the shelf in T condition. It is more highly alloyed than 4130 chome-moly and actually corresponds to SAE 4140.
There have been several variants, each with slightly lower chromium and molybdenum than the original due to the Euro Norms rationalisation. Talk to your supplier.
I use709M40 if 605M36 cannot meet my ruling section requirments. 709M40 can go higher up the tensile range, it also nitrides well."
"817M40 (EN24T) is a long established nickel-chrome-moly steel, extensively used for larger components, or those where high tensile strengths are required.
It can cover tensile ranges W, X and Z up to 29 mm (1 1/4" diameter. It is, in effect, overkill when limited to T range in small sections. Many people use 817M40 on the grounds that is is more expensive.
I don't completely agree ..... Table 2.7 shows the actual mechanical properties of 605M36 T, 709M40 T, and 817M40 samples. You will note there is little to choose except that 817M40 tends to come out towards the top of the range, 709M40 T towards the middle and 605 M36 fractionally lower. Over the years I have talked to many manufacturers and no has been able to give any significant advantages for any one of these three when used in T condition except for 605M36 becomes brittle sooner at very low temperatures (-20°C) than the others.
However one thing is certain 817M40 demands much more careful control of heat treatment than the other two. Faulty heat treatment leads to brittle failure, even in T condition."
For folk like us the big difficulty is getting a foot or so of steel to known composition and heat treatment. 605M36 T with a proper certificate is the only safe choice. Wheel spindles are no place for a steel which may not have the expected impact and shock resistance (709M40 T) or is likely to be vulnerable to brittle failure (817M40 T) if you happen to get the bad bit out of the bar.
Our suppliers aren't equipped to verify properties. They have to take it on trust. I've had some right weird stuff appear that really wasn't what it said on the tin. Generally materials are good but sometimes..... That said the only time I'd make a wheel spindle was if I didn't trust what I could buy. And if it costs silly money for tested material its a darn sight cheaper than my neck.
John MC is quite right in saying that properly selected stainless steel is up to the job but can you actually buy a short length of the right stuff in the right condition.
80M40 (EN8) can only manage tensile range R up to 19 mm (3/4" diameter so not up to it even if you can reliably find it in R condition.
|Thread: Two factor Authentication and Ruralism|
As I understand it all the mobile carrier networks have WiFi calling capability for any mobile phone modern enough to have the "app" embedded in the operating system (all iPhones 5c and later, not sure about Android). There are specific apps for some older ones on some carriers.
Many of the virtual mobile networks piggybacking on the main carrier systems choose not to enable the WiFi calling. I use GiffGaff which doesn't, neither do 1p and a fair few others.
Can't see no WiFi calling being the norm for much longer. Probably only the uber cheap, very basic, providers won't have it.
How about WiFi Calling via your internet connection?
Most reasonably modern phones are up for it but not all cellular networks enable the feature. I imagine two factor ID may push them all into offering it.
Allegedly seamless so you don't know which way the call is going.
|Thread: Painting on old galvanize|
White, silver or other reflective light colour is best. Garage doors get hot in the sunshine and the constant thermal movement shifts most paints in time.
Hammerite tends not to be terribly good as the cover coat is too thick. New fangled worse than old fangled.
There is/was a so called "garage door paint" from, I think, International. Brush on. Not good in my experience.
Were I to do a metal door again I'd be tempted to use many thin coats having had some success with this approach for difficult things in the past.
|Thread: What is this mic used for?|
That style of micrometer head an bock is frequently found on the micrometer adjusted slides / carriers used with optical benches and tables. Usually two counterbored holes to fixt it.
|Thread: What lathe tool for deburring holes?|
I use a flat topped 45° point on a full length 1/2" square HSS toolbit. The bit is sufficiently longer than the Dickson holder to accommodate a point on both ends.
Cutting edges hollow ground using the periphery of an 8" grinding wheel and kept honed really sharp between grinds.
For smaller jobs I use a Shaviv handheld pivoting deburring blade or use a countersink in the tailstock.
If its just a teensy burr I just use the Shaviv, even on bigger jobs.
I've always felt that the fixed blade deburring tools similar to the Shaviv would be dangerous to hand hold in a lathe.
In over 20 years I've only broken one Shaviv blade in the lathe.
|Thread: cutting upholstery foam|
My experience of the reciprocating blade carving knives is that they cut foam well if the blade is longer than what is being cut and you feed at an appropriate rate. Too slow being almost as bad as too fast.
If the cut in the foam is a little less than twice the length of the blade its possible, with some difficulty, to get an adequate cut if some variation around the overlap of the blade is acceptable and the thickness doesn't have to be accurately even.
Cut more than twice the blade length will be uneven in the junction areas. Never found a satisfactory technique for peeling it apart and making a straight cut.
The professional band knife makes the job look trivially easy.
Buy new foam 4" thick.
I, and folk I know, have tried a number of ways to thin down wide, thick, foam. None were objectively successful. All were stressful.
Nearest to success was a large electric carving knife on 18" wide (I think) foam which made it up to a bit below the "Not good but it will ...... have to do" level. Actually the first thing tried but not considered good enough so ....
Hot wire didn't do well at all. Hard to keep good tension and a constant cut speed in wide materials. In retrospect the fumes probably weren't good either.
Other advantage of buying new foam is no regrets when SWMBO says "I wish you hadn't cut the cushions down. They are too hard now."
Edited By Clive Foster on 31/07/2020 14:23:51
|Thread: Inexpensive Induction Heater for Hardening|
Yep. Standard rules apply.
You can do very well for surprisingly little money if you happen to be in the sweet spot.
If you don't know where the sweet spot is or don't manage to hit it the choice is between mega frustration and hello big spender.
Everything is more complicated than it looks at first sight!
|Thread: Higher trolley for surface plate?|
Workshop trolleys rapidly accumulate weight so it shouldn't be too hard to make one like Johns sufficiently bottom heavy to be stable.
I have one that looks to be similar size with four shelves. Bottom three have rectangular washing up bowl size containers stuffed full with, from the bottom, large lathe tools, large lathe tool holders and similar whilst the next to top is not quite full of large chuck keys and similar. Top shelf is full of Dickson T2 holders and some 1/2 " thick indexing notch plates. Maybe pushing 100 lb in the bottom one, seriously over 50 in the next two and probably more on top shelf.
That stays where its put and doesn't wobble. Never dared verify what the official working load of the castors is! Pretty sure its not enough.
|Thread: Inexpensive Induction Heater for Hardening|
Thanks for that Joe
Confirms what I thought that these things are basically a cleaner alternative to propane for heating up smaller components.
I did see a You Tube video of a 1.2 KW one running at 95 KHz which suggested it might be marginally viable with a smaller diameter coil for good coupling efficiency. I agree with that 200 KHz and up is more appropriate for surface hardening.
Still might be worth considering as a heat source for use with case hardening compound though.
The tube I have is copper, not copper plated steel, so if I get one I'll wind something up and give it a try. But if its going to take approaching a minute to get the pin hot water cooling the coil will be essential if the job is to be done quickly.
More to arrange and probably more futzing about than what will turn out to be a break even job is worth. I don't mind spending so much on kitting up that I only break even on a job for another guy if I end up with something I'll use in the future. Which, given the limitations, seems unlikely with this.
Further to my previous query about case hardening steel sources I see that small, naked board, induction heater units can be got very inexpensively. One of those looks to be a lot less mucking about when doing 50 pins than my Sievert gear.
Are they sufficiently repeatable for reliable case hardening and what size would I need to handle the 2" long, 1/4" diameter pins. I'm thinking the nominal 1000 W or thereabouts jobbies would be about right.
Standard coils look to be too fat and short for my job. Presumably I can wind a longer, thinner one from copper tube. I have some copper brake tube in stock (supplied wrongly when I ordered Kunifer so need to use it for something else less critical).
Are they capable of surface hardening a steel such as 708M40 (EN19) if used for an appropriate time before oil quenching? Obviously I'd need to start with annealed material first. Which may be an issue.
|Thread: Wire colours for Brook Gryphon motor|
When doing this sort of thing I use my cheap (LiDL) laminator to make a durable label with the colours and any other useful data on it. The small "business card" film sizes work well for this. Cut the paper to the right size and trim excess laminator film, it stays stuck together just fine.
|Thread: Sources for case hardening or pre-hard steel|
Thanks for the quick response. Looks like 070M20 (EN3) from M-Machine is a good fall back position if I can't find proper case hardening steel.
(Dunno what the last lot of so called EN3 supplied locally actually was but 070M30 it certainly wasn't as only carbide tooling would touch the stuff! 40 ft of grief in 12 mm bar form.)
Given the opportunity I always prefer to have the right thing rather than something which "can" do the job. Most of the time "can" do works just fine but there are always "gotchas" lying in wait for the unwary and inexperienced.
This particular job landed on my doorstep because commercial supplies are what the customer calls "cheap crap" and the good makes don't produce that size and style. Why the commercial supplier produces essentially unhardened crap rather than doing it right is beyond me, hardening isn't exactly expensive in commercial quantities, and the machining is basic.
John, producing a hard case on ANSI 4140 by quenching from below the critical temperature certainly seems to be a known, considered reliable, technique in certain quarters. That sort of below critical temperature quenching will do "something" to the surface hardness of any steel with sufficient carbon to be heat treatable by simple means. Whether the "something" is actually what you expect, or the results even desirable, and whether the results are reliable without doing unpleasant things to the core properties of the material being horses of a completely different colour of course.
Been asked to make 50 simple components that need a hard surface. I'm having problems finding a source of case hardening steel. I'll need about 3 metres of 1/4" or 8 mm round bar.
Either 130M15 (EN21) or 080M15 (EN32C) would be best but I imagine there may be other more readily available steels that take a case without core properties being too badly affected. Only about half the length needs to be hardened and these things need to be quite stiff.
An alternative that might do would be a pre-hard steel equivalent to the American ANSI 4140 pre-hard as RC 35 to 40 ought to be fine for this job.
Worst case fall-back would be linear rail but I'll need to put a thin spiral groove of around 50 tpi, fortunately not critical, along about half of it. Finding a tool up to the job may be a problem. My machines are ex-industry and well up to the task given suitable tooling
Heating and quenching ANSI 4140 at below the critical temperature which is is said to produce a case of around RC 40. As 709M40 (EN19) is essentially the same as ANSI 4140 I guess its possible to do the same. Quenching from 1375° F / 745° C is said to be best. As critical temperature for ANSI 4140 is given as 1575°F / 875°C there seem to be reasonable margin for error but one does wonder if a tempering stage will be needed to ensure that there is no possibility of the core cracking.
Although this would get me to what seems to be an appropriate surface hardness for the job it seems an awful faff unless you are set up for this sort of job. Which I'm not. Case hardening about 3 times a decade is about my speed.
|Thread: Higher trolley for surface plate?|
Further to what Frances said about heavy duty drawer slides I scavenged a few from old filing cabinets for that sort of job but never got round to engineering the sliding bit. Personally I'd want a bit of poistive support at the front for stability even if not explictly necessary to carry the load.
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