Blocking car assembled vs. panel by panel

I'm just about to the point where I'll need to start blocking my Mustang. I've got it completely torn down and have all the panels and body in epoxy primer. For this step I did it panel by panel. However, I now have all these panels and not enough room. I will have to do some test fits with new valance panels anyways so I'll have to assemble the car before I tear it down again for edging.

It sure is easier to block everything when I can just lay it out on a stand and work on it, but I almost risk damaging the panels more by constantly having to move them around.

What are the advantages and disadvantages of blocking the car as an entire assembled unit? All seams will be sealed by this point.

Thanks in advance, you guys are always so helpful.


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actually, I think blocking it on the car is easier cause it stays still. you can always put your fenders on with just two bolts and take it off when you need to block the edges, and you can also mess with the height of the fender so your block doesn't touch the door or messes with your sanding stroke. for the edge of the door to quarter you can just open the door, but if you like it on a stand more power to you. Just be mindful of high spots that can be created on the top of your fender from the stand. With that said, I have noticed my work turns out better for the first round of primer when I focus on single panels doing them one at a time, and that's cause it's easier to be more thorough. It's most likely cause when you do filler work on a car you tend to fill a lot of stuff each time you mix and you tend to miss tiny stuff once in a while doing it that way. Just my two cents.

Your two cents is worth ten dollars to me. You brought up some good points I hadn't thought of. You also made me remember how frustrating it is to keep the panels still while sanding them (I had already blocked the fenders last summer)...something I apparently have already forgotten but no doubt would be quickly reminded.

I do enjoy your videos, by the way. They usually get a few laughs from me.

thanks. I think it's crucial to ad humor into it or it won't be too much fun to make and cause I've dealt with a lot of people in this trade that have sticks up their butts.

In my experience you should have the car assembled and all panels adjusted to their final resting place before final sanding. This way all the lines can be sanded from one panel to the other thus giving a cleaner transition from panel to panel. Make sure the door edges and such are good otherwise you'll end up with a thick edge which makes it look like a "bondo bucket".
For most paints I'd recommend stripping the car apart again for painting so you get paint on all back sides and no join lines in the jambs and such.

Great to hear, this is exactly what I was planning on too.

I agree..

HI,while i have the car apart for body work,i sand all the seams,then prime good,sand again,then mask off panel,and paint only the seams ,reassemble the car,final blocking the primer,then shoot the paint.

For me it's apart unless we use pearls or other effects
If it is a 2 tone, tape it assembled and paint it apart