Broaching

[Belair62]

Here is a 63 409 engine...untouched...seems they didn't machine or broach them early on like they did later///anyone know when they changed machining ??...this shows it better

http://img.photobucket.com/albums/v140/Belair62/a%2063/tn64home006.jpg

[allcamaro]

So now im really mixed up. http://www.yenko.net/ubbthreads/images/graemlins/cool.gif

[Salvatore]

Is this your motor Bob?

[Zedder]

I know that all Corvette blocks have broach marks even back in the '50's...I'd say that block has been machined at some point.

[Belair62]

Yes Sam and it hasn't ever been machined.

[Charley Lillard]

Looks to me like it has been machined.

[Belair62]

I was the first guy to pull the pan off the thing...standard bore,factory pistons...can't see them machining the deck and missing the numbers...never been re-stamped unless it was done in the 60's http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

[Mr70]

Could it have been done in the 70's?
I didn't think the circular machines were used until then.

[Seattle Sam]

Could it have required additional machining at the factory, before the numbers were ever put on it?

[Belair62]

Did anyone give a crap about an original stamping on a 409 in the 70's ? I doubt it...you could still get crate 409's then too...pan has never been off until last night !! Unless someone took a 6 inch sanding pad and gave it a cleaning. The "high" spots in the stampings are a bit shiny...

[JoeG]

Letters look crip Bob from where I'm sitting and no machine line before the numbers, but I'm a couple of states away----I'd say nay on the machining ---But the cylinders looked bored too hell-- http://www.yenko.net/ubbthreads/images/graemlins/tongue.gif http://www.yenko.net/ubbthreads/images/graemlins/wink.gif

[Belair62]

Nah Joe...this is an 814 block...the 64 needs a 422...this one is still standard...so will the 422 be when I'm done. http://www.yenko.net/ubbthreads/images/graemlins/naughty.gif

[mrrec]

Bob:
I've seen untouched blocks with no apparent machine marks like yours. I've never liked the term "broach" as I don't think it applies to a one dimensional removal of material - keyways or holes are broached. My educated guess is that the "broach" marks everyone talks about are actually the machine marks left by a planer.

Unlike a rotary milling cutter (which were certainly in use prior to the 70's), a planer has a moveable bed which can be quite large (10'x 50' or more) so that a large number of blocks can be planed at once. The cutting tool(s) is fixed and the work piece (block) moves in relation to it. The tool "shaves" the iron in a straight line parallel to the crank. This method was apparently more economical for large production runs than milling using a rotary cutter in years past. Planers were widely used from the 1800's through WWII and are almost non-existant in production in any industry today.

I believe the planer (broach) marks could and did vary considerably depending upon the cut, tool profile, etc.

Dave

[Belair62]

Planing marks are what we all are used to...these are circular patter it seems but hairline...I know it was not restamped or monkeyed with so the only thing I can figure is a light cleanup with something circular...guess it doesn't matter anyway. http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

[Verne_Frantz]

Bob,
I'm very certain those machining marks are original, and so are the stampings. I'll email you another photo of an original you can post for comparison.
(what's the Julian date on the back of that 814 block?)

Verne

[Belair62]

320 Verne....thanks for the help with the 64 too..together we are going to figure this weird old car out !!!

[Mr70]

I would just sell it now & cut your loses while you can.

[Zedder]

Dave, you are absolutely correct, but they never left circular marks like on Bob's block. They are always parallel to the crank and varied in depth (some almost non-existant to the naked eye) depending on how sharp the broaching tool was. Some one (I think John Hinkley) wrote and article on the process for the NCRS driveline I believe.

Maybe it was sanded in some way to leave that pattern, but in NCRS-type judging it would not pass inspection.

[Verne_Frantz]

Mark,
With all due respect, I think you are referring to Flint machining operations (small blocks). These big boys are made at Tonawanda. Different method of deck grinding.

Verne http://www.yenko.net/ubbthreads/images/graemlins/smile.gif

[Zedder]

Verne, I have judged and owned numerous Tonawanda big blocks and they all have "broach" marks. Now I can't comment on blocks earlier than '66, but my guess is they used that process back then also. I'm sure someone will chime in and clear this up for us all. I'll ask Art Armstrong and see if he knows...

[Belair62]

[ QUOTE ]
but they never left circular marks like on Bob's block

[/ QUOTE ]

I have pictures of great planing marks from Tonawanda too...but I will post more pics of other '09's from Verne later..Take the blinders off fellas..maybe that 74 degree deck was cause for a different method.

[Zedder]

Bob, like I said, I don't know anything about pre '66 cars, so I'm just saying that it "appears" to have been machined and that I have never heard of any factory decking process other than broaching. I've posted the question on a private site that I am a member of for John H. or Art A. to respond to and will post their replies. Maybe we'll learn something new http://www.yenko.net/ubbthreads/images/graemlins/beers.gif

[Belair62]

That would be interesting...the pics I have of mine and a couple from Verne show the same method http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif Plus I would never let a Corvette judge look at it...

[kwhizz]

[ QUOTE ]
I would just sell it now & cut your loses while you can.

[/ QUOTE ]

http://www.yenko.net/ubbthreads/images/graemlins/haha.gif http://www.yenko.net/ubbthreads/images/graemlins/haha.gif http://www.yenko.net/ubbthreads/images/graemlins/haha.gif http://www.yenko.net/ubbthreads/images/graemlins/haha.gif http://www.yenko.net/ubbthreads/images/graemlins/haha.gif

Ken http://www.yenko.net/ubbthreads/images/graemlins/flag.gif

[Belair62]

[ QUOTE ]
John H. or Art A. to respond to and will post their replies

[/ QUOTE ] Who are these folks ? Do they know 409 stuff ?

[SamLBInj]

Ill bet it was just sanded and cleaned up a little to change the gasket..to light for machining..looks like the guy was right handed.. http://www.yenko.net/ubbthreads/images/graemlins/scholar.gif

[Leonard1]

Check out this post from JohnZ over at Camaros.net It shows a pic of the broach machine at Tonawanda.
http://www.camaros.net/forums/showthread.php?t=59125&highlight=broach

[Zedder]

[ QUOTE ]
[ QUOTE ]
John H. or Art A. to respond to and will post their replies

[/ QUOTE ] Who are these folks ?

[/ QUOTE ]

Just some GM engineers from the '60's...no one special http://www.yenko.net/ubbthreads/images/graemlins/tongue.gif

No worries about Corvette judges wanting to look at your car... http://www.yenko.net/ubbthreads/images/graemlins/smirk.gif

[Belair62]

Cool...pick their brain on 409's...see if there was a different method ...all the examples I've seen are like the above...keep the Vette guys by your place and entertain them. http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif....BTW very cool pic of the broaching machine on that link...thats a 90 degree deck angle so I am really curious about the 74 degree now unlees that thing was adjustable which I doubt.

[JoeG]

Hey Bob!--I found one the guys working on the assembly line that day-------------- http://www.yenko.net/attachments/166106-cavean.jpg

[Belair62]

http://www.yenko.net/ubbthreads/images/graemlins/haha.gif http://www.yenko.net/ubbthreads/images/graemlins/haha.gif

[Belair62]

Couple more originals....no doubt...top one I had to shrink and you can't really make the circular pattern out

http://img.photobucket.com/albums/v140/Belair62/a%2063/64engine409-QB.jpg
http://img.photobucket.com/albums/v140/Belair62/a%2063/belairpadstamp.jpg

[SamLBInj]

I enhanced them for you..

[SamLBInj]

here is another
http://www.yenko.net/attachments/166283-belairpadstamp2aa.jpg

[SamLBInj]

close up, looks good
http://www.yenko.net/attachments/166284-belairclosup.jpg

[Belair62]

Any word from those experts yet Zedder ???

[Zedder]

Art didn't respond yet, but John did. He had no direct knowledge of the 409 build but mentioned that perhaps they did something different given the different angle. As I think it was Phil that commented the best way to "prove" the block hasn't been messed with is to compare it to other known originals. The pics you posted look pretty good (although the stampings on one are pretty crooked for a factory stamp), so I'd feel better about your block now. I tried to find some other pics on-line for you but they are nowhere to be found.

I'll see if I can get Art to comment.

[Belair62]

I was not at all worried about my block...I know it's untouched..I was pointing out the different style of machining for the 409....another interesting item is last letter of the sufix-- A,B,C are stamped after the Tonawanda number was stamped....they were all "Q" blocks...the A ,B ,C, was stamped after the HP rating was determined by order. Pretty different animal. http://www.yenko.net/ubbthreads/images/graemlins/smile.gif

[Pacecarjeff]

What does the other side look like?
Is the swirl pattern also on that side?

Since the head is off, what about farther down towards the back of the block, is it there too.

I am curious.

[Belair62]

Its the same Jeff...all the 409 pics are the same that I've seen too...different for sure...still no answer as to why ...the second set of pics are from Verne Frantz who has been working with these since him and Moses graduated high school.... http://www.yenko.net/ubbthreads/images/graemlins/haha.gif

[Verne_Frantz]

"who has been working with these since him and Moses graduated high school....
"

Thanks a lot Bob..... http://www.yenko.net/ubbthreads/images/graemlins/blush.gif

I have (lets say more than 2) original blocks which were purchased loooooooooong before 409 cars were being "built" in the hobby. They all have the arched (circular) grinding patterns on the decks, front to back, both banks.

I have had technical discussions with both Art and John, and I respect their knowledge and experience VERY much. They are both gentlemen and I believe very probably among the most valuable great assets for correct historical reference we have within our collective hobbies................however I will say that if you are the bottom line authority on apples, that doesn't make you qualified to document oranges.
I like oranges. http://www.yenko.net/ubbthreads/images/graemlins/flag.gif

Verne http://www.yenko.net/ubbthreads/images/graemlins/smile.gif

[Belair62]

http://www.yenko.net/ubbthreads/images/graemlins/haha.gif http://www.yenko.net/ubbthreads/images/graemlins/biggthumpup.gif I like Apples and Oranges !!

[Steve Shauger]

We all knew you were a fruit Bob. BTW very interesting topic... ya learn something every day.
http://www.yenko.net/ubbthreads/images/graemlins/worship.gif

[Pacecarjeff]

[ QUOTE ]
We all knew you were a fruit Bob. BTW very interesting topic... ya learn something every day.
http://www.yenko.net/ubbthreads/images/graemlins/worship.gif

[/ QUOTE ]

This is very interesting - different technique for sure.
http://www.yenko.net/ubbthreads/images/graemlins/shocked.gif

[JoeG]

[ QUOTE ]
--- Verne Frantz who has been working with these since him and Moses graduated high school.... http://www.yenko.net/ubbthreads/images/graemlins/haha.gif

[/ QUOTE ]
And I always thought Moses and Verne got that white hair from the burning bush http://www.yenko.net/ubbthreads/images/graemlins/hmmm.gif I guess it was from the sparks when God created the first 409 http://www.yenko.net/ubbthreads/images/graemlins/dunno.gif

[Verne_Frantz]

You know Joe,................I could think of something else you could be doing besides spending time on the computer..............the weather is changing fast, you know.

http://www.yenko.net/ubbthreads/images/graemlins/beers.gif

[P.J.]

I am not an expert on locks by any strech of the imagination, however I have spent 30 years or more
Machining all kinds of materials with Planers and milling machine, shapers and surface grinders ect. Bobs explantion in his previous post is right about the Planer. However
this bock has been machined with a carbide fly cutter either by the factory or by someone else.A fly cutter is a
round tool with one or more carbide inserts and can range form 2 inch diameter to 12 inch diameter depending on the area to cut with multiple carbide cutters .There is no doubt about it. It cant be a blanchard grinder because thats what is used to grind your flywheel.If the bock had a blemish after it was planed and before it was stamped then
the factory would put it aside and machine them with a fly cutter later on together with other blemished bocks.
If the block then cleaned up and was within the tolerance
then it would then continued to be assembled and then stamped
hope that helps
suprss70