Hi GR,

They are a NATA registered Laboritory and Metalurgy is what they do every day for a living. I have had them carry out similar tests with meaningful results, mostly on gearbox parts. All their test methods will form part of the certification. The HRc method of testing is very accurate at the surface upon which is being tested. Any errors or uncertainties will also form part of the documentation. It is extremely transparent. No, I don't know at all what the results will be, if I did, I wouldn't bother with the exersise. It may well be nitrided to 60 thou, but only testing will bring this out.

Having NATA Certification means they have to answer to someone and they are regularly audited. If you have any doubts regarding the accuracy of their testing or the honesty of it, talk to these guys;-

http://www.nata.asn.au/

And this is what their Lab holds NATA Certification on;-

http://www.nata.asn.au/index.php/scopei ... &postcode=

It's OK, have faith.

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Hi graham, it gets me why they always have to keep changing things like the steel codes. Gives some pen pusher something to do.
when I started m/eng in 1968 we had to cover metalurgy in infinate detail as on ships there are 100's of different grades of steel not to mention cast iron, non-ferris and aluminium. So I have had plenty of experience with most metals, and now days the engineering plastics are also included.

I am not too sure when they dropped the Ni from en40b but the early blackstone engines[ late 1940's] had their cranks made from en40b with Ni. the code was stamped onto the crank and the manuals stated that if the crank was re-ground it was to be tuftrited only on the journal area. Some where in my collection of old books there is a picture and discription of the process. They used crushed bone and chared leather packed around the crank journals when it was in the furnace.

From what I have learnt about alumin. included for nitriding it only forms a very thin layer[.002-004] of aluminium nitrate on the surface. It is not a complete layer just mixed into the surface.

4140 is better suited to induction or flame hardening than nitriding. I have used it many times to make high pressure pump shafts and flame hardened it. It does not have a problem with surface cracks done like that.

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Research is the difference between speculation and investment. Anyone who copys some one else will always be second
www.minisprintgt.com

Oh we got bent cranks out of the tank most of the time ,,, that`s why (if anyone cares to re-read some of my crank blurbs from ages ago in other topics) dad would ask that the grinders grind the cranks to .002" over the nominal size that we want to eventually end up at,,, then he`d have the crank balanced (to remove any mad big chunks if need be) , then he`d have them hardened (for the weekend process) & then he`d have them ground true--> straighened

now in this final grind, any bend will be "True-ed" up (straightened),,,

BUT!!! also,,, the slightly oversize journals (left ever-so slightly large on purpose remember) would ground down from their usually even-more "over-grown" size from the hardening process making them grow bigger too,,, & because they would nearly always bend a tad (some more than others) ,, then we could grind them down straightening them with enough meat left to do so,,, & as much hardening crust "Thickness" as we could, , , there was nearly always enough meat to grind them true to the size we want when we did them this way,,, but not always,,, i`ve seen some pretty wild shape cranks come out & oops,,, that one has basically "stress-relieved" itself in a big way

Oh & then of course we`d send them off for their final balance (yes again) & this balance would be barely a little skim/pollish here & there (mostly)

& dad has always been very anal about his rolled-fillet/radius (-es-i ) ? nice, wide, smooth & big diam radius-es-i ,,, Yummy tell your mummy,,, i don`t mind narrowing down some bearings if i have too,,, because if i have to do that then i have big radius-es-i



it is "i" isn`t it??? the plural of radius

It`s not "es" is it???

so is it radii ???

i must have been asleep in that English class lesson

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Matt, PM sent

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I know sod all about hardening cranks (heh.. I might use that term to describe myself these days ) but I do know you're right, it's radii

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Simon

The adventures of an owner builder in the Tallarook Ranges

Matt,

I'm interested to hear how you narrow the bearings down, as I am rebuilding a lump with a billet crank that has big radiuses that has been riding the bearings on the fillets.

fortunatly the crank is fine and it has just taken the bearing back to the copper, I might be able to get around it by off setting the trust bearings, (+10's in the rad end and grind the others to suit), but i leke to keep my optioms open.

Hi GR,

Just wish to let you know that I have placed an Order for the Test to be carried out and they are expecting to take delivery of the sample (again, when you get a chance or if you have it sent by courier).

The company has changed their Trading name since I used them last and Stephen appears to be on leave.

The Company is now called;-

ALS Laboritory Industrial Group (also known as Pearl Street - go figure!)
Same address (6 Nello Place, Wetherill Park)
Ask for Azharul.

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Hi GR,

I have been discussing your concerns with the Tester (re Rockwell Testing), while he says it is appropriate, he has agreed (subject to seeing the sample first hand) to carry out Hardness Testing by the Vickers method as this only uses a 1kg load, however, depending on results, the standard does allow the use of a 10kg load (if it is particularly hard). He will also determine the depth of the treatment (if any) eg Nitriding. I'm just keeping an open mind.

<EDIT> following email from Azharul

Thanks for the photograph of the sample to be tested. If the straight portion of the sample length is too short then we may have to either use a sub-size specimen for tensile test or just get approximate tensile strength conversion from the hardness test. The steel appears to have been marked as EN40, which is considered suitable for nitriding.

I look forward to receiving the sample.

Regards

Azharul

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Hi GT MOWOG
Did not finish on the dyno till late today will take it over tomorrow
Graham Russell

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"It's better to be not informed than ill-informed"

No worries, you did say you were busy.

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Hi GR,

I understand you dropped off the sample for test today. I have received the following from Azharul:-

We have received your Crankshaft sample today through Graham Russell (that is name mentioned on the business card). It does not provide enough straight length for carrying out a tensile test. Therefore, we will have to rely on chemical analysis, core hardness, surface hardness, microscopic examination of the case and determination of the case depth through HV1 hardness measurements.

We will need your confirmation to proceed with the testing.

Regards

Azharul Haq
Senior Materials Consultant

ALS | Industrial Division

Do you object to this in anyway? We need agreement before I can instruct him to proceed.

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HI GTMOWOG
I think the cost of this through them is going to be very high i spoke to Steve Hooker about doing it he has all the equipment to do it he will only charge $150 and you can have all the results sent to you.Whooops sorry no i don't object
Graham Russell

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"It's better to be not informed than ill-informed"

OK, I will ask them to proceed.

On the subject of costs, the offer I made earlier still stand soild. I have a quote which is very reasonable considering what needs to be done.

BTW, is your college Steve Hooker NATA Accredited?

And thanks for taking the time to drop it in.

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I have asked Azharul to proceed with the Tests as previously agreed to and I also asked him to include a diameter measurement of the journals, so as it can be determined if it has previously been re-ground and any factory finish / surface treatment removed.

This was his reply;-

'As discussed, we will measure the required diameters of your crankshaft sample using our calibrated micrometer/vernier caliper and provide a separate non-NATA report, which will also include a couple of photographs of the as-received samples'

Their lab is not NATA Accredited for physical measurement, hence why that will be on a seperate non-NATA report, however, it is an independant measurment. He has also indicated that we should have Test Results in around 14 days. Stay tuned........

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A long time ago, I worked in a heat treatment factory (both as a heat treater, and as their metals tester), case hardening, neutral hardening, tempering, annealing. Everything from screws, to ford transmission parts, but only ever talked about nitriding!
This topic, whatever the outcome is so fascinating!
Even from a bloke who used both a rockwell machine, and a vickers machine, the depths (no pun intended! ) that the information has gone into is astounding!
Thumbs up guys!!

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Chuck Norris is the only person alive who can kick you in the back of the face!!
mooo, I'm a pig!