I would suggest keep going until clean, but make sure you maintain the radius on them. When your done grinding, polish them up with some wet & dry or emery to really clean them up. Then harden (the rockers that is). Dave's technique for hardening sounds good (and I am still talking about the rockers!)

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Hey, thanks for the info, found that photobucket has an app for my Android phone as well!

Now, back to the topic...

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'68 Morris Mini 1310 A+ (Now Sold!)

YES, it was. and it was quicker than all others.

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Thanks everyone. I haven't grabbed the fish oil yet, but I will do on the morrow and finish them off.

The last time I tried quenching cherry red metal in oil resulted in the oil bursting into flame. I wonder if fish oil is flammable?

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

If I can just elaborate on that a little.... clean them with thinners, heat till dull cherry, quench in oil and shake so as not to let any bubbles or air sit on the work piece and then polish... then reheat till they are a browny yellow and quech again... the last part is to temper them.


<edit> can't help you on the fish oil,,, I usually use motor oil.... and welding gloves

If the item that you are quenching gets too close to the surface while still extremely hot, then the heat will cause the escaping smoke to burst into flames.
Very natural for this to happen, and very common. Just do it in a deep container, with lots of oil. Keep agitating the piece continuously without getting too close to the surface.
Having only done it professionally, I couldnt tell you how fish oil goes, but we heated all tool steels in sodium cianide at temperatures between 1100 and 1400 degrees celcius.

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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!

Hi 850man
The miniman is right henrys car was not an 850 the block was with a 998 crank and plus .060 pistons, and when he run against our mini 1000 at winton he was 2 to 2.5 seconds a lap slower, go back and have a look at the records.
Graham Russell

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

only one way to find out, ill bring the fire extinguisher just encase

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"if its got tits or tires it'll cost yah"

Always happy for witnesses. Tupperware may not be a good choice for the oil container..

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SooperDooperMiniCooperExpertEngineering

All garage work involves equal measures of enthusiasm, ingenuity and a fair degree of irresponsibility.

Hi Mick
If you heat the rocker up with the oxy torch to a red heat then put a magnet on it if it sticks to it it's not hot enough give it a little bit more so it just does'nt stick to it and that will be very close to the right heat then quench it in the oil, if it's a good piece of molly steel it should be around the 60 rockwell C mark but it will be brittle, so as phat kak said re heat it till you just see the blue colour start to appear thats just after the straw colour and quench it againand you should be right,thats how i do some of my big camshafts to try and make them last.
Graham Russell

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

I dont want to hijack Micks thread about his rockers so I will keep this brief.
HDs 850 Targa engine was built over 10 years ago by JK in NMPs workshop and I was there helping him, along with building the gearbox, brakes, entire car. It used a 850 block and a new 998A+ crank, rods, std size A+ flat top pistons, along with a number of other modifications. For many years Henry compeated in the Targa Tasmaina and was often the quickest mini of all, often quicker than much larger, more powerfull cars as well. The car was built as a Rally car, not a race car so there is no surprise that a 1000 powered, much lighter race car is quicker. My point was not who has the fastest mini or most HP A series engine, rather that 1.5 Roller rockers can be used with various camshafts, heads, compression ratios etc in a non 1275 A series engine with good results.

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Yeah? You let them temper to a blue do you?

I was a little undesided.

Usually around the brown yellow stage is a good mid way I've found and you don't normally go too far wrong... blue is starting to get on the softer end of the scale, and not knowing for sure what the rockers are made out of (though molly steel alloy would make sense) if it isn't a great steel to start with, tempering it till blue ""could"" leave it a little open to pitting or bruising.... just a thought..


Alex

Mick, I can give you the name & number of a profesional Heat treaters here in melbourne just incase you dont want to wave the oxy around and burn your hose down with a Tsunami of burning oil They do a lot of automotive gear and are very good.

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I'm not sure I will be able to get to the blue stage with my propane torch.

Orange/yellow I will by minimising heat transfer to the jaws of the holding vice, but I fear might end up overheating the rocker shaft bush if I apply the propane over too long a period. As long as it is the tip of the rocker turning orange only, will the bush maintain its integrity?

Ooooooo good question... their a bronze bush are they? See, yellow heat is only 250 odd degrees C.... so I doubt it would hurt the bush... BUT now that you mention it, during the hardening side, that dull cherry is about 750.... I don't play with bronze.... I don't know when it starts moving... thats a question for a Fitter


<EDIT PLEASE READ VERY IMPORTANT JUST TO BE CLEAR> when you'r tempering, your looking for a yellow film,,,, not a glowing yellow from getting the steel nearer molten, that kind of yellow happens around the 1200degree mark