Tempering bolts

I am with Ed and Buerste. But if you are feeling adventurous you might try looking up "Super Quench " on the internet. I have not tried it and do not ever expect to try it. Low alloy steel is just not that much more expensive if you really need hardness or high strength. But it is interesting to read about. Super Quench is a brine solution with detergent and a wetting agent added. And is claimed to be able to somewhat harden 1018 steel.
=20 Dan
Reply to
dcaster
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I'm with you, but when you tell your heat treater to "carburize and heat treat," they first have to soak the part in a carburizing atmosphere at some temperature a little below the Curie point, for a shorter or longer period of time, depending on how thick you want the case to be, to carburize it. Then then heat it above the Curie point and quench. That's the heat-treat part. It doesn't work just by wrapping the part in stainless foil and heating it, and then quenching. You need a source of extra carbon.
That's what we do in a small way with Casenit. Sometimes I've wrapped parts in foil AFTER dipping them in Casenit, to get a thicker case. More often, I just put on a thin case by dipping it per the instructions on the can.
-- Ed Huntress
Reply to
Ed Huntress
Might not be that oddball. I just did a brake line repair and had to find a similar 6mm bubble-flared line with a 12mm fitting. Went to about four auto parts stores, finally located it a brand new (well stocked) store.
Reply to
ATP*
Well, it appears to be pretty peculiar in these parts. Even at a European specialty shop.
The other problem I'm going to run into is: I may be able to obtain lengths of 6mm tubing and flare nuts (I have a flaring tool). But I'm going to have to custom fit (cut to length, bend and flare) the tube to fit the car. Its either that or a junk yard to find parts for a 30 year old car.
Reply to
Paul Hovnanian P.E.
When I replaced the brake line that snakes across the front of my truck I modeled it with wire first, then bent the brake line out in the open to match. IIRC I used several shorter pieces to determine the length between bends. Aluminum TIG wire is particularly nice to hand bend, it's stiff until you start the bend and then the bent spot seems to soften, the opposite of steel that work-hardens at the bend.
jsw
Reply to
Jim Wilkins
Speaking from the right hand side of the pond, every metric brake pipe I've come across on European roadgoing vehicles has used 1/4" (6.35mm) tube.
Kunifer (90Cu-10Ni), that anyone with any sense uses on a vehicle they want to keep long term, isn't even supplied in any metric sizes!
Reply to
Mike
Hmm. Made the tubing nuts. They work great (no hardening needed). I bought a chunk of 1/4" (6.3mm, close enough to 6mm) brake line, pre-flared. The factory flares are what I understand to be 'double flared', with the tubing actually folded back into itself. Unfortunately, I had to cut this down to length and flare the cut end. All I have is a tool for doing single flares, so I went with that.
The factory flare leaked, mine didn't!
This is welded tubing. It appears that the 'folded back' edge cracked slightly when I tightened the nut on it (spark plug tight). I'm guessing that my single flare stretches the metal less, since the maximum (only) bend is the 45 degree corner at the base of the flare.
Reply to
Paul Hovnanian P.E.
Did you check the sealing faces on the fitting cone and on the factory flare? Sometimes you want to buff them up a bit with Scotchbrite to make sure that there aren't any little scratchers that cause leaks.
The whole reason behind insisting on a double flare is that the cut end is not being stretched - when the double flare is done right the stress is in 'virgin' metal and the cut end isn't disturbed much. You are stretching in the middle of the sheet, and it tends to do it without ripping.
On a single flare, the cut end of the tubing is stretched out quite a bit to form the flare cone and is under the most stress. If a crack forms it can easily spread past the fluid seal point. With hydraulic brakes ther is no tolerance for leaks - you have very little reserve fluid, and leaking fluid getting on the linings wrecks the system efficiency even before the fluid runs out.
Go buy the tool that does proper double flares, and redo it the right way. Think of the first attempt as either "Practice" or a "bending pattern" or "Proof Of Concept", whichever one sets your mind at ease for the duplicated effort. Unless you make it a habit to ignore those initials P.E. (that allegedly indicate an Engineering Degree) when it's inconvenient ortoo much trouble or too expensive to do the right thing...
Yeah, I fight dirty. Deal with it. ;-P
You are free to do the repairs on your own car in an unsafe manner if it's only you involved, and only you that gets potentially hurt or killed. Kill yourself because your shortcut bit you in the ass, and it's a shame.
But most cars seat more than one person so you are putting relatives and friends in a dangerous position as a passenger - as well as the drivers of other vehicles on the road you could hit. If someone else gets seriously hurt of killed because you took a shortcut instead of doing the repairs safely, then it becomes a provable crime.
-->--
Reply to
Bruce L. Bergman
I have a double flare tool. Have not used it in at least 40 years. I just go to the auto parts house and buy the correct length of brake line. If can not get the exact length needed, put a loop in the line. I remember Shelby GT350 when it came out had copper brazed brake line. Failed and car crashed bad. Driver is still walking lopsided. Use the correct stuff for safety. I see a jury rig like that on a PE that I hires car. He would have his contract cancelled immediately.
Reply to
Calif Bill
I have made a few good double flares and a few more bad ones. I have had no success with cheap imported flaring tools but I have a Snap-On/Blue-Point one which works much better. I have found that it is very important that the tubing end be cut very clean and straight. A very slight bevel on the outside seems to help but it needs to be uniform. A little lubrication seems to help too. I generally make several practice flares each time I attempt it.
Don Young
Reply to
Don Young
> ... > =A0 Go buy the tool that does proper double flares, and redo it the > right way. =A0Think of the first attempt as either "Practice" or a > "bending pattern" or "Proof Of Concept", whichever one sets your mind > at ease for the duplicated effort. =A0... > =A0 =A0 =A0--
Reply to
Jim Wilkins
Somewhere along the line the fact that this is a clutch line, not a brake line, has been lost. Much lower pressures in the system, and a huge difference in the likely consequences of a failure.
Reply to
Ned Simmons
Yanno.... I don't know. My first thought would be an acid etch, neutralize, dye penetrant, then stick it under a microscope or magnifying glass looking for little fractures waiting to get big.
If you are running a company that mass produces car parts there's probably a solution so you can spot-check the products- but they usually are not cheap, and a non-destructive one is usually REALLY not cheap.
-->--
Reply to
Bruce L. Bergman
Not going to tone it down much... Even if it's "only" the clutch that quits releasing, if you're dealing with traffic and trying to downshift for a curve or an exit ramp, watching for little cars in your blind spot, already busier than a one armed paperhanger - then you throw in a failure like that on top of it...
You can still end up in a crash. Workload overload. Try juggling too many balls at once and inevitably something's gonna get dropped - you are already at your limit and some smartass tosses in two more... -->--
Reply to
Bruce L. Bergman
i had a clutch slave cylinder fail in an underground car park.
Put in reverse, start engine, move back, kill engine. Put in forward, start engine, move forward, kill engine. Repeat, repeat etc.
Bloody women would not give way to allow me to get out. I think they were too intent on getting a parking bay and ignored all other vehicles.
Reply to
Alan

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