When Did Broach Marks Stop?

[Steven B.]

Re: When Did Broach Marks Stop?

Nice search Harry. Well done.

I almost began to weep at the names of those posters. A large number of my best friends posted there. I tried to count those who are deceased, but couldn't get to all of them. It is a shame the skill and knowledge we have lost.

Right Terry. So many old friends and the knowledge and memories past. So much not documented and answers that wont be available in the future or at least accurately. Some of the memories will live on for a time. Time to ask those questions now. For me time to recall the first time I met the owner of my 57 and our 60 year life long friendship. Ask those questions now and laugh those laughs.

[David H.]

Re: When Did Broach Marks Stop?

... Are the engine and accessory fasteners SAE or Metric? ... If the threaded hole is in the case, cyl head or some other component (intake manifold) that was threaded in the engine plant, it is SAE. ... ...

Dave

Metric threads in cylinder head for spark plugs.

Dave

[Dave P.]

Re: When Did Broach Marks Stop?

Metric threads in cylinder head for spark plugs.

All spark plugs used in Chevrolet engines in the past 60-ish years have been metric. In fact only a 7/8-18 thread with a 7/8, 15/16, or 1" Hex are currently catalogued. Every other thread for any spark plug currently catalogued is Metric. You're technically correct, give yourself a pat on the back for a nothing-burger. You're an ass for calling me out on this. Don't quote me and call me out. Piss-off.

My post was written more as a hint as to which wrench to grab. Spark Plugs used in Legacy Chevrolet engines have a 5/8 or 13/16 hex. My "metric or SAE" holds for plugs as well.

[David H.]

Re: When Did Broach Marks Stop?

All spark plugs used in Chevrolet engines in the past 60-ish years have been metric. In fact only a 7/8-18 thread with a 7/8, 15/16, or 1" Hex are currently catalogued. Every other thread for any spark plug currently catalogued is Metric. You're technically correct, give yourself a pat on the back for a nothing-burger. You're an ass for calling me out on this. Don't quote me and call me out. Piss-off.

My post was written more as a hint as to which wrench to grab. Spark Plugs used in Legacy Chevrolet engines have a 5/8 or 13/16 hex. My "metric or SAE" holds for plugs as well.

Dave

Chevrolet began using metric plugs in early 1930's. So about last 90 years!

Dave

And Seasons Greetings to you too.

[Kenneth B.]

Re: When Did Broach Marks Stop?

Cast iron blocks were NOT painted at the foundry like other smaller parts. They were painted at the engine plant after machining. Paint was only to not see rusty parts on a new car.On the broaching thing aluminum would not broach well. Its gummy & needs cutting fluid while CI is machined dry.

[Mark F.]

Re: When Did Broach Marks Stop?

[Mark F.]

Cast iron blocks were NOT painted at the foundry like other smaller parts. That's what I have seen, too - no block painting in the foundry They were painted at the engine plant after machining. Paint was only to not see rusty parts on a new car. On the broaching thing aluminum would not broach well. Its gummy & needs cutting fluid while CI is machined dry.

My original post #36 apparently got corrupted during the transition...I'll try to recreate as best I can (briefly)...

I don't know how GM broached their blocks (wet ? dry?), but while I did a job at Ford's Dearborn Engine Plant on one of their broach machines '78 to '81 timeframe...broaching and cylinder head bolt hole drill and tap tooling were drenched in water-based cutting fluids as the parts passed thru an enclosure on the conveyor...

The block entered the enclosure; passed under the broaching tools 1st as they contacted the required to-be-machined surfaces with huge quantities of cutting fluids directed at the cutting points thru multiple spray nozzles; then the block moved to the drill and tap tooling at the next position; then exit to the downstream processes afterwards.

IIRC these two machining processes took roughly 30 seconds to complete...
Fascinating to watch 😊

Happy New Year !