View Full Version : How To Cut And Fit Sheet Metal


05-26-2007, 02:45 AM
Hi Guys

I'm still a newbie with cutting and fitting sheet metal. Haven't try to fit yet.
I'm in the stages of just cutting-out rusty ol' floor pans.

My '66 Mustang Convert. needs lots of love n care.


How do you cut sheet metal so that it fit (butts) up against the original sheet metal that's in good shape in my car :confused:

I don't want to over-lap the sheet metal. I want to butt weld it.

Any and all ideas will be greatly appreciated. :)

Thanks guys

Schooner :cool:

05-26-2007, 08:45 AM
i usually use a piece of thin cardboard(like from a shoe box) to make a template to draw on the sheet metal then cut it down the outside of the line i made and then finesse it with a grinder till it fits just about perfectly.

05-26-2007, 09:59 AM
Hi Dave

Thank you so much for that simple but great advice.
Now why didn't " i " think of that with my rust ol' 66yr. old brain :rolleyes:

Pliable cardboard, gotcha Dave.
This way I can either butt weld or over lap the sheet metal joint.
I'll take me time Tweaking it, nice an easy.

Now on to my hunt for the right kind of cardboard that I can make a template. :)

Regular brown from cardboard boxes is to stiff and will bend in the wrong places. Need something better ~ any ideas my good man.

Thanks Dave

Schooner :cool:

05-26-2007, 10:43 AM
Making templates is a super way to do anything like this.

But if you are going to butt weld, I do it a little different. I use the template to get it real close, maybe within an inch or less. But instead of grinding it to fit (this works as well of course) I clamp the new part in real tight and then scribe a line right on the edge with a nice sharpe scribe to get a super accurate line. Then you can grind or cut right up to the line for a flawless fit.


“Basics of Basics” Templates for accurate cutting and drilling.
By Brian Martin

Making templates is something that a lot of guys have a hard time doing. It is not that it is hard to do, it’s that we hate to “waste” time. Let me tell you right now, making templates SAVES time. You can quickly make them while installing emblems, patch panels, quarters, roofs, floors, and more. Anywhere you would splice, drill holes, or even painting graphics or stripes. With a template you can copy dimensions off the old part, the new part, or even another car you have access to. You can then these to the car you are working on.
The need for a template comes into play when you are working with an odd shaped part in particular. Is easy to mark something like a ½ pipe. You just measure the length with your tape or ruler, mark it and cut it. It is not that easy to measure and mark something like a roof post or fender.
I may have over simplified the process a little in my drawings but it really is this easy.

Now, this is not a “Basics” on quarter panel or roof replacement. You wouldn’t necessarily splice a quarter or roof this way, though you could, this is just not that “Basics”.

Figures A and D are the starting points on cutting off and replacing this roof or for that matter the quarter. You’ll need to find a place to cut it, then transfer this information to the new part. You could of course make the template off the new part and then transfer the information to the your car. By doing this you will cut off the old part and be able to set the new part right up on the car and it should fit perfect or near perfect.

These drawings show two different ways to use and make templates in body repair. There are other says, these are just two and of course this roof post is just one of the many, many places you can use a template.

Figures A, B, and C show using a thin paper template over the pillar. Figures D, E, and F show using a cardboard or poster board to make a template along the edge of the pillar. I use the paper method about 90% of the time. The cardboard or poster board technique is good for things like locating a heavy angular item like a frame cross-member.

I have found that 3M welding shield paper (part number 05916) works well for the templates. It is flexible yet stiff enough. And the best part is it has a mild adhesive on the back to hold the template in place while making it and while transferring the information to the other part. The glue is sort of like a “Sticky note” and the template is easily removed and reapplied without tearing the paper or leaving any glue behind, it really works well.
You want to apply whatever paper you use like a sheet of contact paper. You want it to “hug” the lines on the metal like a sticker would, with out air bubbles even. An air bubble wouldn’t make a bit of difference, but just so you have a good idea of that I mean, it should fit like a tight glove over the part. The closer it is to the actual shape of the part the closer it will be to the OTHER part where you will be putting it to transfer your information.
Now, I know what you are thinking. The paper will change shape as you pull it up off the first part right? Yes it will, but if you have press it down tight and marked it with your “control points” it can easily be removed and reapplied to the other part perfectly straight.
“Control points” (numbers 1 thru 9 in the drawings) are points of reference that can be found in exactly the same place on both the new and old parts. These control points can be mounting holes, sharp folds, sharp edges, some panels even have notches that line up parts for assembly. If you make your template using these control points, then transfer your template using them to the other part, you can be assured it will be perfectly aligned. You now transfer the cut lines, holes or what ever to the other part.
One very important thing about these control points is you have to be sure they are EXACTLY the same from one part to the other. You can do this with a measuring tape and/or another template. As an example look at the B or C drawing. If you were to measure or make a template that included number 4, 8, and 9 then you could go to the other part and ensure they were the same. Now, you could with confidence use the number 4 as I did in the drawing. You need to REALLY be sure they are the same from on part to another because if you use something that is not the same from one to the other, you template will mean nothing. The control points number 1, 2 and three are a little different in that it really doesn’t matter if they are off a little tiny bit from one part to the other because you KNOW they are at least close enough to work, I mean they did, right? You are not always going to use some thing like numbers 1, 2 or 3. In fact, you hardly will. Most control points will be like the others in the drawings.

In the figures E and F you will see that the cardboard or poster board is held behind the panels and then you just run your pen or pencil along the edge to mark it. You can cut the template as I did in the drawing E. Or you could just mark it and then hold the template next to the other part and line up the marks as you made them on the first part. Then you could make a little mark on the part where the cut line will be and then draw a line across the part to meet the other mark.
By the way if you are going to use anything like masking tape to mark for cuts, be sure to mark the side of the tape you will be cutting on with arrows or something. If you think that I have never cut on the wrong side, you would be wrong. I started marking the tape long ago, it doesn’t take me too many times cutting on the wrong side to learn that trick.

Just today I used the A, B, C method. I spliced a new quarter onto a VW Jetta. This template was for the rocker area. The old quarter was very badly damaged right at the front of the wheel well. And the new quarter was cut off right in the middle of the rear door jab in the rocker (on most late model cars the rocker, front hinge pillar, center hinge pillar on a four door, roof rail, and quarter are all on piece). I forgot to make a template before cutting the new quarter off the rest of the part. So now I had the back half of the rocker connected to the “dog leg” on the new quarter. And the same area on the old quarter was destroyed . This left me with a little harder template to make. I found that there as a holes along the bottom of the rocker that were the same on both parts. There was also a little notch on the top of the rocker where the door rubber went on. So that is all I needed. I laid the 3M welding shield paper over the new part so it hung off the end of the front where I had cut it off and it was hanging off the top and the bottom of the rocker right where it spot welds to the inner rocker. As I said, it was pressed down into the body lines TIGHT. I even pressed the paper as it runs down the edge of the metal almost cutting the paper. I pressed it down into the holes on the bottom and into the notches real good. Then I took a razor blade and cut off the excess paper on the top, bottom, and end. The other end of the paper ended right at the dog leg. The length at that point really doesn’t matter, as long as it includes a control point. Like in figure B, the paper above the number 1 control point and below the number 2 control point is doing nothing, so it could be a foot longer or an inch longer it really doesn’t matter. Mine ended right in front of the lower hole in the rocker and upper notch. I then carefully peeled it off the new part and stuck it onto the car lining up those control points. I pressed it down into the body lines just as it was on the new panel. The cut line was marked on the out side of the end of the template where I had cut the excess paper off when it was on the new quarter. This would ensure that the cut would be EXACTLY in the same place as the cut on the new quarter had. I removed the template, cut the rocker on the cut line, drilled out all the remaining spot welds and removed the rocker and quarter. I then trial fit the quarter and rocker and the rocker cut lined up perfect, providing me with a perfect door gap even. It really is that simple! The top of the roof post on this particular car was installed as it was from the factory with only a little splice in the jamb area. For that “template” I actually used a little piece I cut off the old quarter to mark the cut line on the new quarter, worked great.

To be continued on next post. :)

05-26-2007, 10:46 AM
Now the nagging on getting as much education as you can. I used these methods every once and a while. Then after almost 25 years in the business I went to an ICAR class (a nationally known training and testing group for auto body professional) and they drilled templates into us as being the RIGHT way to do it. I went back to work and started using them all the time. They really do save time, it is amazing how much time they save. No cutting and grinding, trial fitting over and over. I also find that template work great for reinstalling glue on emblems and mouldings. Most cars these days have glue on emblems, no holes, just stick them on. So what I do is as I am taking them off, I run a strip of tape under them right along a body line. Then off the edge of the panel (this is usually on the deck lid where you find these glue on emblems) and mark it on the edge and on the tape where the emblem is located away from the edge of the lid with a “Sharpie” pen. I even write the word that is on the emblem and maybe a note if needed about location, left right, that sort of thing. I then peel this tape off the lid and stick it to the inside of the window on that side of the car. When the car is all done painting and back in my stall for re-assembly all I do is peel the tape off the inside of the rear window, stick it on the car where it was before and install the new emblems.

You could use them to record how high the fender sat compared to the rad support. You could record where the bumpers sit in relation to the body, the uses are endless. If you are pulling a car apart for a restoration, you know it will be apart for a LONG time. If you think for one minute that you will remember these little details you’re wrong. Make templates, mark them and store them. You will be very glad you did.


05-26-2007, 11:21 AM
By the way, I wrote this "Basics" a few years ago. And of course I have used the templates on many projects. But one of them lately really shined.

I was installing an SMC ("fiberglass") inner fender on a C6 (2006) Vette. I had never done one, you see they "glue" onto the aluminum frame and firewell and rad support. And this adhesive is very thick. It is up to a quarter inch in places. So this inner fender is sitting on a bunch of "Beds" of adhesive. The inner fender could be slid all over the place, forward or back up or down a quarter inch or more in each direction. The fender bolts right onto this part. So if it were up or down the fender wouldn't fit with the hood or door.

They are put on at the factory with some sort of jig holding them as the adhesive cures.

To replace them in the shop is a whole different story.

Soooooo, I made up a pile of these little templates like in figures E and F in the drawings. I made a quick "map" on where they go and numbered them. I bonded the part on, never even trial fitting the fender on the car. I simply put the inner fender EXACTLY where the original one was.

The fender was painted off the car and I bolted it on for a perfect fit. :) Yes, templates are VERY useful.


05-26-2007, 12:55 PM
This man is a master at his craft, what they call an artist. Suppose it all makes sense though. Instead of cutting and wasting metal hoping and praying to get it right then having to fudge it to get a good fit.

So off to the garage I go to make me some templates for welding this weekend.

Glad I got three days off, looks like I may need it:rolleyes:

05-27-2007, 12:15 AM
Hi Dave

Thank you so much for that simple but great advice.
Now why didn't " i " think of that with my rust ol' 66yr. old brain :rolleyes:

Pliable cardboard, gotcha Dave.
This way I can either butt weld or over lap the sheet metal joint.
I'll take me time Tweaking it, nice an easy.

Now on to my hunt for the right kind of cardboard that I can make a template. :)

Regular brown from cardboard boxes is to stiff and will bend in the wrong places. Need something better ~ any ideas my good man.

Thanks Dave

Schooner :cool:
Just another note about Brian, MARTNSR; if you go to the home page of this site, click on CLASSROOM and look for lots more of his writings along with other people.

ANYWAY, you need to think about supporting the car with pole jacks to keep the car from sagging DEPENDING what and where you start cutting. The floor in that car is an integral part of the unibody structure. I'm not saying you can't cut out a hunk of floor and weld in a new piece without supporting with pole jacks, I'm saying depending where and HOW MUCH you cut; don't get ahead of yourself. Henry

05-27-2007, 02:10 AM
Hi Henry

First of all THANKS for your input.

Henry, I have my level and off my garage floor about 3ft.
I have a 2x2x1/4 sq. tubing under the outer rocker panel with 2 jacks holding it in position.

Before I cut-out any further I''m going to mig weld a 4ft. piece of angle iron on the inside of the door frame on passengers side.

All this Henry my frame won't sag and I'll be unable to close the door properly.
So far I've cut-out the torque box and started on the toe board and front floor pan.

I'm stopping now and I'm going to mig weld that angle iron in position.
Thanks for you concern.

GOD bless

Schooner :cool:

05-28-2007, 05:21 PM
Schooner I am currently working on a 65 mustang convertible. I have finally finished all the sheet metal replacements on the body. I am using a mustang brace that goes accross each door opening and then crosses into and bolts to the transmission hump where the shifter mounts. Pretty slick. I found it online somewhere, not too expensive, but it does keep the body from flexing and twisting. I have it on a home made rotisserie.
What I use for templates is the cereal box card board. Firm enough but still plenty flexible.

05-29-2007, 08:23 AM
I am using a mustang brace that goes accross each door opening and then crosses into and bolts to the transmission hump where the shifter mounts. Pretty slick. I found it online somewhere, not too expensive, but it does keep the body from flexing and twisting.

Could you please post any other info you have on this brace? I did a Google search and didn't find anything, and I haven't heard of this on any of the Mustang forums I frequent.
I am working on a 69 coupe myself. :)


05-29-2007, 05:56 PM
Hi Frm187

Well guy we're not to far off as far as our cars go. You with a '65 and me with a '66.

Let me first say this; I'm new at all this restoration stuff, sheet metal, mig welding. However, I'm no stranger to elec. & Tig welding. Been around welding and steel for some 17yrs.

Funny thing though with all the welding I did do, I never touch MIG.

At the present time here's where I am with my Convert.

I have to replace the following: (one side at a time of course)

Both Torque Boxes
Both Toe Boards
Both Front Fl. Pans
Both Inner Rocker Panels
Both Rear Seat Pan
Both Rear Seat Extension Pan


Right now I've jacked-up my car (passender side )with 2x2x1/4in. sq. tubling .Two jacks are holding up the tubing in place so door won't SAG when I cut-out the inner rocker panel. If the door side sags I won't be albe to close the door properly. (I'd be screwed)

Queston: Have you had to do this with your car? If so I'm open to any suggestions that you might have :confused:

I already cut-out the Torque Box ~ Damn with a job that was. Thank GOD I didn't cut where I wasn't suppose 2 :rolleyes:

I started cuting out the Toe Board and some of the Front Fl. Pan but of these two pieces I only cut out part the way.

I'm gearing up to cut that darn Inner Rocker Panel Out. I'm waiting on a 1/2in.
Spot Weld Remover Bit that's suppose to be coming in the mail.

That's about it my man.
Any and all suggestions to help me see it a better way I will be very greateful.


Schooner :cool:

05-29-2007, 06:18 PM
Could you please post any other info you have on this brace? I did a Google search and didn't find anything, and I haven't heard of this on any of the Mustang forums I frequent.
I am working on a 69 coupe myself. :)


Hey Russ

Maybe you got the wrong guy. I didn't say anything about a brace that I have. As a matter of fact I would love to see the darn thing myself.

At the present time I'm bracing up the bottom of the right side of my door in order to remove the rusty ol' Inner Rocker Panel. I don't want the door to sag.

Take care
Schooner :cool:

05-30-2007, 08:42 AM
Schooner, russ69coupe was replying to fmr187. See who the quote is attributed to?

05-30-2007, 10:28 PM
Here (http://www.accessiblesystems.com/mdb01.php) is a link to a door brace for a '65-66 Mustang convertible. There is no use for such on a coupe, as the roof of the car accomplishes the same thing.

The way I like to fit floorpans on a Mustang is to remove about an inch less of the old pan as you are going to replace. Cut your replacement pan about an inch and a half bigger and lay it in place. Use self-tapping screws to secure the pan in place, including where it meets the frame rails. Using a cutoff wheel or a body saw, begin cutting about a half inch from the cut edge of the replacement pan through both layers of sheetmetal. Cut about a foot and bend the metal to be removed away (cut it off if it's in your way). Using a hammer, tap the replacement pan flush with the original sheetmetal and tack it. Move an inch further and do the same. Repeat this until you get to the end of your cut. Cut another 12 inches and repeat until you get back to where you started. Then go back and fill the gaps between the tacks. Grind your welds from the underside and you'll have an invisible repair.

An easier, albeit more expensive, way to do a Mustang floorpan is to buy one of the new Dynacorn full floorpans. Insist on the Dynacorn part, as the cheaper version is thinner and doesn't fit very good. Any Scott Drake dealer can supply this part (I happen to be one ;)). Here (http://www.scottdrake.net/prod_details.aspx?prod_id=8108&breadcrumb=Sheet+Metal+%26+Body+Parts+%3a%3a+Chass is+%3a%3a+Floor+Pan%2c+Complete) is a link to the SD website that shows the part. It retails for $526.95 and requires truck freight to ship it. It completely replaces the original pan and you spot/plug weld it in place instead of butt welding.

05-31-2007, 09:26 AM
Hi Jmoffett

Great advice on that Brace. I bought it today 5/31

Thanks to you, I figured I might as well do it RIGHT and NOT take the chance that my doors will Sag while I'm chopping away at those Inner Rocker Panels, one at a time. Now I won't have to worry about my door(s) Sagging while I'm cutting away.
What a headach that would turn out to be if I didn't buy that brace.

So I wait for the UPS guy to come by with me brace. ;)

Meahwhile I'll be taking off my doors. I'm going to mark the hinges with a sharpie so that when its time to put 'em back I'll have an exact spot to hook 'em up again. ( unless you have a better I idea on how to do that)

Can't tell you how much you straighten me out on the Door & Body Brace :)

Take care my man

Schooner :cool:

05-31-2007, 11:58 AM
If you mark your hinges with a Sharpie, then paint your jambs with the doors off, you'll lose your marks. I would be inclined to mark it with a carbide-tip metal scribe. This will leave a physical line in the metal that you won't likely see when the hinges are back in place. There will still be some minor adjustments necessary when you put everything back together.

If you want to get the doors EXACTLY where they were, and if the doors are EXACTLY where you want them to be, drill two 1/4" holes through each half of the hinge into the door and the A-pillar. When you get ready to hang your doors, use a couple of 1/4" alignment pins to align the hinges and tap them into the holes before you cinch the bolts down. If your doors have ever been adjusted to account for worn hinge pins, you need to repair those first.

05-31-2007, 01:06 PM
The brace that Jmoffett provided the link to is the brace that I was referring too. You should be pleased with it when it arrives. Dont know if that is the same vendor or not but when mine came it didnt come with bolts to bolt it to the car. But it does the trick of keeping the body from twisting. Good luck with the project. There is a very helpful web site for Mustangs called vintage mustang. (vintagemustang.com). Very helpful.