TECH: 40 Mercury chop,1 man-1 roof-1 week

Preface:
THIS is an on-going chop that I am doing here, in the shop ,so the pics will be posted in succession ,as I complete it.
I have been tinkering with it about two weeks or so -but actually the work involved can REALLY be done in a week by one man.

I should be finished tomorrow afternoon -so the finished pics will be tomorrow evening.
This may be of interest to some here as I have seen many of these being built as customs.
There are many ways to do this top -what I am proposing here is a slightly different approach-one that I most usually have to consider.....

IN EFFECT=If you are like me you have to do what you can accomplish by yourself or with very little help.
Also I ,like others, have very rarely got access to a spare [and rareBTW] 40 MERC donor roof,and even if it is to be from another different car it still is a job and an added expense we rarely have time for!

I apologize--in my infinite wisdom - screwed up right off the start by taking the -BEFORE- pics on a throwaway camera[for owner]...and only have digital pics from the second stage on.....sorry- you will just have to look at your car to see how damned ugly these coupes are UNCHOPPED!!Ha!!
[The 39-40Mercs are actually 5 window coupes -but this will also end up being a hardtop when chopped.]

 

This is a 5" chop at front and a 7" chop at rear..... the A-W/S posts are cut at mid point as one suspects- and then the rear is a horizontal 7" slice -remmoved from the C posts.

the B posts are sawed off at top and bottom and discarded.....

the rear C posts are gonna end up too narrow for the wider base of the body where they used to reside.... so you will beed to make a straight incision about from the rear of roof corner to the door post line[on center of the roofs side"crown".
You'll notice that I RE CUT the upper windshield area and RAISED the top UP 1-1/2".
This is for twofold reasons....One it gets rid of that overchopped pinched lookin windshield and TWO- it allows a little more flexibility in spreading the upper roof to same width as the posts are on body side....

It is really, fairly close for a 5" chop and can be easily spread wit your own strength by tacking one side and pulling the other over to line up! so in effect what we end up with is a 3-1/2" chopped w/s and 5&7" on the side gl***es!
The windshield cut is done like this...
mark the 5" to be cut out of frt posts.
then mark another line at 3-1/2" across the 5"cutout area too...
Then go IN from the w/s opening 1" and mark a VERTICAL line upabout a foot long.
Next measure 2" above the w/s opening and mark a straight line parellel to each half of opening.....this line will meet the vertical line at top of WS post...round the croner like the corner of W/S opening to match....
doing this will leave your weld seam 1/2" above the opening....THIS way no pieces have to be added when raisng the W/S top....

 

Dam I'am going to have to go do the old lady now.You just gave me a woody with that picture

 

Now on to more important stuff.....

WHen the top is cut 7" at rear a whole lot of "not fitting back" is about to rear its ugly head!
like I said before -you will have to make a relief cut about 4 feet long statring above mid roof at door line towards the rear corners....this allows the C posts to be spread wider to re fit to quarters...
Next is the parts where this top chop differs slightly from the average chop.

Most folks-will at this time cut the majority of the "whales ***"- HUMP that 40 Merc's had out and pitch it -in favor of a donor -roofskin/cap of a smoother persuasion.....
this is what I do- you can do whatever ya like....
Iwas given the request from owner to lower the rear gl*** down to where he can see out when backing up.....so,I opted to not chop the rear gl*** at all.
Instead what I did was to mark a line across below the rear gl*** opening about 3/4" below the gasket area-straight across....
Not being able to see the future,suscks -If I had done what I suggest to you it would fit even better!
MARK the straight line wher I said-THEN at the center below center post- drop down 1" and make a mark....then with a straightedge mark from cenmter of that to the ends of the pevious marked line we drew first!
this will result in an arc ending lower in the middle and taapering up towards each end...it will eliminate the need to make filler peices as I DID...
Next you can take a cable pull or "come along"- and hook around the center post of rear gl*** at center...hook to rear bumper or frame in center...
Then set the C posts ON TOP of each side of the qtr panels......
with doors latched and a shim placed in the door lines to maintain the gapsBE SURE THEY FIT.....
tack the C posts to qtrs TEMPORARILY FOR NOW....

 

NOW= a disclaimer- for the all the knowit all-critics.... WHO......

Noticed that,I never braced the body and I never sanded off all the paint and shined the metal for at least a week!
Im a professional-put down your hand -I don't need your input-go set down...... Ha!
The "not bracing the car" deal is only important when you do not have a body on its frame securely or have done floor work....
YES.....car should be on level and checked for fit intermittently.

In effect -if the doors are fitting squarely in their openings and are not hanging out at top or the bottom and all gaps are adequate- ITS RIGHT!

leavin on the paint is just plain smart- how better can you see the contours and the "condition" of your sheet metal rather than in paints reflections!
Plus- you can always grind off the paint before the filler is applied-right??
You can see here how badly the peices sag inwards after cutting...
I cut out the worst of the curved-ill fitting corners of C pillars.......

 

Now we have the C-pillars tacked in and the roof pulled DOWN AND BACK to where we need no donor roof-right?

Next we have to address the large now missing corner panels....

I rolled one out, on the wheeling machine for this place...
If you have none you can make the missing panel froma cardboard template first in flat steel..then if you have a sheet metal break do this.
Ever so slightly tweak the breaks starting with the peice in the break lengthwise every 1/4' barely bending it. move in both directions repeating this.. the turn it 180 degrees and repeat the same subtle bends the second direction....
this will give it some curvature,and you can hammer/dolly out the slight lines the break leaves.....

 

Now- you notice above that the areas that are tacked together at their seams are still low.....

That is where the [TM]-ONE MAN-top chopping- Fixtures are brought into play......

I call these apparatus's= "two by fours" ......cause thats what they most resemble!
COUPLED -With a few select blocks of wood [in the cars floor] and these 4 lengths of wood ,you can easily replace -four of your whining&complaining -beer ****ing friends ,who are never available when you are working.

they, will easily push any part of these seams up into the realm of acceptance,where when finally filled with filler metal and welded -you can hammer and dolly the worked seams flat.

 

Here are a few more pics one of the windshield lift up and one of the rear with Fibergl*** applied to seams.....and a side view.....
This will be a cool custom- it was a down in the frt street rod...
Owner ***ures me it will get serious rear lowering and skirts and BLACK PAINT!!!!!
it is kinda hard to get a perspective on the final-look of a car, when it sets the exact opposite of its "end" result...but that is what keeps us on our toes -right?
This about where I'm at today- so thats it for pics till tomorrow evening....Thanks for lookin!

 

I have more 2x4's than buddy's. Glad to see someone else 'fessing up to a similar situation.

That chop looks great...

 

Awesome post. That's one of the hardest Mercs to chop. Interesting spreading solution, the top slice that runs way up front.

The post came out good, I'm not missing the photos lost.

 

WOW!

I think we may have a weiner!

Awsome car and work, can't wait to see it done! You gonna loose the antenna? It actually doesn't look too bad. I have the same steering wheel in my truck

mazdaslam, you taking notes???

 

Killer!!!

 

Mike- what I mean is I had no BEFORE pics posted....Im a dumb***.
BY THE WAY-I also forgot to say that the strip removed BELOW the rear gl*** was 3" wide at each end and[tapering to 2" in middle]

 

killer...

Danny

 

For a guy who did all that work and still had time to post, your good ,** your real good.

 

HA! like in any type skilled job -this stuff actually takes longer to ****yze and plan than to actually do the work![that is IF you do that sort of planning]

 

Si Si....Taking notes . Nice way to do the windshield.Looks good.

 

Choprods id the f*#kin man!!! Nice work, nice.

 

nice work. thanks for sharing

 

Keep posting you progress you doing a real good job, I wish I have the time and the talent to plan and build a car like that. I can't wait to see her when she is finished. Good luck.

 

Very Well Done , You Do Very Nice Work.

 

Damn, I wish I had dem skillz! If you don't mind me askin', How many chops do you have under your belt? And, what's a chop like that cost? You got the skills to pay the bills my friend. I love threads such as these.

 

Kenny- No doubt amazing work by you once again. You keep out doing yourself time and time again. Just glad to own a Choprods chopped truck myself. You keep appreciating the value!!!!

 

Very nice, Choprods.

 

Very nice!!!!

 

Your chop would make Sam Barris very proud. If I was president I would make it a law that all '39 '40 Mercs have to be chopped. Great job!!!!!!

Happy Trails,

Mick

 

excellent post chopped.The 2x4s was a great idea.mike

 

CHOPRODS I love all of your posts! But this one is killer. I gotta contact you for advice when I chop my '50 suburban.

 

THIS IS GREAT INFO!!!!!!!!!!!!. If you remember or not I posted about two months ago on the one I am chopping and I have run into a road block with the front post. You have just given the hidden answer. I will posting the one I am chopping and I think mine is worse since I have to replace the whole roof skin due to it being rusted out. Please post the finished job. One question for you. Did you weld up the front post first and then bring the rear of the roof down, or did you bring the roof down all at once?