Chroming a Lotus just does not seem right to me. But there is an
embrittlement relief procedure that requires you to bake the part. The
table shows ranges from a half hour at 500 degrees to 23 hours at 325
degrees. You can bake the part yourself to relieve embrittlement after it
is chromed, but ask the folks at the plating shop for the proper tables.
It may not be right, but I still like the chrome trim rings around my S2
wheels, so do as I say not as I do.
Fred
65 Elan S2
65 Elan S1
61 Elva Courier
At 12:10 PM 10/10/2001 -0500, Phil Ethier wrote:
>I managed to make out to the last MAC MOWOG-Series autocross of the season
>with "Grace N. Violence", my Lotus Europa. I didn't bother putting the
>headlights back in, as I am still planning on painting the car "real soon
>now".
>
>It is a lot easier to get coolant in now because there is a bleed screw atop
>the new water pump. The car ran a bit rough as I started off for the
>ballpark. I gave it an "Italian tune-up" on a deserted stretch of road and
>it ran fine all day after that.
>
>There was an interesting course laid out on the stadium parking lot. A
>couple of places demanded that you plan ahead or you would find yourself on
>the wrong side of the track. The most noticeable feature was a pin-turn
>with lots of room around it.
>
>MAC split the entrants into four groups. I was in group three, so I worked
>the course as group one took their first set of three runs. It was still
>pretty cold, and the cars were sliding around quite a bit on the asphalt.
>It was clear and dry, so I figured it would warm up to 60F or so and
>traction would improve somewhat.
>
>On my first three runs, I realized that you can't keep 185-60-13 R1s in
>baggies for five years and expect them to stick. ;-) I slewed around
>quite a bit but managed to keep the front wheels in front and the car
>between the cones. I only assassinated pylons on the second run. The timer
>box announced a not-really-embarrassing time at the end of my third run. I
>had hope for the next round.
>
>It was warmer as the afternoon wore on, and times were dropping. I wondered
>if my tires would take advantage of higher surface temperature. If they
>did, I didn't know what to do about it. On my fourth and fifth runs, folks
>told me the car looked great, but my times were a second slower than my
>third run. My sixth run, I made two mistakes, including getting into an
>understeer coming off the pin-turn and wound up even slower. So I had to
>stand on my third run, which was not awful, but others did improve and I was
>not among the fastest cars there.
>
>I took Paul, our local Marcos enthusiast, for a fun run in a car as low as
>his. A bit messy, but autocrossing Grace is always a hoot anyway. Even on
>dodgy tires, the car always feels way faster than it is, and that
>formula-car feel is different from what most folks are used to.
>
>Now we come to our metallurgical lesson for the day. Rex, my Saturn
>compatriot, wanted to see what the course looked like from a viewpoint lower
>than that of his SC2. We strapped in and pulled up to the marshaling line.
>I did my customary launch and BANG. The car didn't move. I switched off
>the engine, turned to Rex and said, "Sorry, Rex. No fun run for you today.
>I just broke the car." I suspected a U-joint. I remembered that Chuck had
>just popped a nearly-new Spicer U-joint in his Datsun Z-car this season and
>wondered if that was the deal. We got out of the car and I lifted the rear
>deck lid. Nope. U-joints are fine. Left halfshaft was shattered. Not
>bent. Not twisted. Shattered. The left-rear tire exhibited serious
>negative camber since the halfshaft normally serves as the upper control
>arm.
>
>We pushed the car aside (lots of fun with the tire rubbing on the inner
>fender panel) and continued fun runs whilst I fished out my motor-club card
>and cellphone. Flatbedded the car back to my place. I was happy to see
>that the truck had large nylon straps which held the car down via the tires.
>Rex came over to help me push Grace back into the shop.
>
>So what's the metallurgical lesson? I took a chance back in 1991 when I
>stared rebuilding this car, and it took this many autocross launches for it
>to catch up to me. One of the previous owners had a chrome fetish.
>Pulleys. Rear cross-member. Valve-cover. Swirl pot. Yes, halfshafts. So
>this winter I am going to do what I ought to have done in 1991: Take out
>the hydrogen-embrittled chrome halfshafts and replace them with
>plain-looking non-hydrogen-embrittled ones. I imagine the usual Lotus
>suppliers will have them. If not, any driveshaft shop can make them up. It
>is hardly rocket science, and the U-joints are not rare types.
>
>For our British friends:
>
>halfshaft = drive shaft
>driveshaft = propeller shaft
>U-joint = Hooke joint
>
>Phil Ethier Saint Paul Minnesota USA
>1970 Lotus Europa, 1992 Saturn SL2, 1986 Suburban, 1962 Triumph TR4 CT2846L
>LOON, MAC pethier@isd.net http://www.mnautox.com/
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