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General Category => Project Builds => Topic started by: brushwolf on 2026-02-10 17:37

Title: 57 Convertible rear bow dimension?
Post by: brushwolf on 2026-02-10 17:37
This was a parts car but I have been working on it intermittently for years. It had only shreds of the original top  left, so I do not have original dimensions for the rear bow. This is critical for correct positioning of the new top from what I understand. So, anyone with a (57 or 58) convertible can give me the measurement from leading edge of panel center to middle of the tacking strip, I would appreciate it. Tired of fruitless searches for info on this and reading about Mazda, Rambler, Mustang and Firebird top installs, that while minimally useful do not have this dimension. Wired up mine and it shows 21" from very edge of panel to center of rear bow tack strip. How does this measurement compare with your convertible. Want to put top pads on before painting commences and all bows need to be correctly positioned for that. Thanks, Mike
Title: Re: 57 Convertible rear bow dimension?
Post by: thomasso on 2026-02-11 11:16
I don't remember exactly and am not at home for a couple more months, but the dimension is in the service manual, I think it was around 21 22 inches.
Title: Re: 57 Convertible rear bow dimension?
Post by: mustang6984 on 2026-02-11 13:39
Quote from: thomasso on 2026-02-11 11:16I don't remember exactly and am not at home for a couple more months, but the dimension is in the service manual, I think it was around 21 22 inches.

I have one in my shop. I'll be down there later today working on my trailer. Let me look for you...see if I can find what Thomasso said.
Title: Re: 57 Convertible rear bow dimension?
Post by: brushwolf on 2026-02-11 16:03
I have the old 57 and 58 shop manuals and a reproduction 1957 Ford body, trim and sealant manual. All 3 have depictions of convertible tops and some even show a designation of that measurement with a number 8 or what looks like a handwritten cursive capital E on the document originally reproduced into a manual, but nowhere is the number "8" in the 58 manual or "E" designated distance defined in the 57 manual.

Granted, I have not studied them cover to cover recently, but they seem more useful for identifying components, fasteners, and for drive train repairs, but are not very specific on measurements of things that were unlikely to be deteriorated or in question when these cars were near new. Lots of more in-depth pages on retractable top mechanism too, but that is not what I am working on right now.

So, figured I will just have to find someone with a 57 or 58 convertible instead of endless internet searches or wasting huge amounts of time paging through old manuals.  Edit: Looks like the "8" in the 57 manual is actually a capital "C" overlaid with a short-footed capital "L" when photographed and blown up and the cursive capital E in the 58 manual is also a capital "C" with a short-footed capital "L" superimposed on it. No idea what that means..
Title: Re: 57 Convertible rear bow dimension?
Post by: brushwolf on 2026-02-11 16:44
The 57 repro body manual clearly shows it as CL also, probably meaning centerline... but no dimensions given...
Title: Re: 57 Convertible rear bow dimension?
Post by: mustang6984 on 2026-02-11 18:10
I have looked in my '57 shop manual (original, not a reproduction) and saw no specific measurements.
Alvin has a convertible in his shop that he built from scratch. I'll send him an e- and see if he has some info.
Later...Hugh

P.S. I sent him an inquiry at 6:15 P.M. CST...he may not see it until morning. But if he has any answers...he'll share.
Title: Re: 57 Convertible rear bow dimension?
Post by: brushwolf on 2026-02-11 18:32
Thank you..
Title: Re: 57 Convertible rear bow dimension?
Post by: mustang6984 on 2026-02-12 09:27
Mike...does this help?
https://www.hydroe.com/products/rear-tack-bow-1957-58-ford-fairlane-sunliner
Title: Re: 57 Convertible rear bow dimension?
Post by: brushwolf on 2026-02-12 09:50
Those are the tacking strips down in the rear of the well area (aka trim sticks), below the back window.
While I find it interesting that several vendors have these trim stick parts, virtually no vendors carry proper dimensions of tacking strip material for the header or the 3 bows that follow it. I am guessing that is cuz the well sticks bring a lot more money. I got the tacking strips for the topside bows from several different suppliers (including DC..). Not one of them fit right cuz material is wrong dimensions in thickness, width, or both. Even looked at supplierd for GM and Mopar. They all sell the same generic crap saying it fits your application, but it does not.
Ended up having to glue and screw multiple layers of material together (and sand the sheen off the semi-hard plastic for each tack strip length on both sides) before gluing them together. Then when you curve them to fit ends of bows the layers want to separate from the curvature, so have to clamp and screw them as well.

But, when you have to make do with wrong or inadequate part and materials, then that's what you do.
Title: Re: 57 Convertible rear bow dimension?
Post by: alvin stadel on 2026-02-12 12:09
I measured mine this morning, and this is what mine is. From the center of the back edge of the well to the center of the tack strip it is 22 in.  My car has been done since 2003 and still works perfectly.  By the way my car left the factory as a 2DHT it had been hit hard on thr right side, I had a rusted out convert with a good frame and top parts, so I mounted the hardtop body on th convert frame, cut both cars apart and built me a rust free convert. It looks like factory. If I live another 79 years, I woild never do that again, Very large learning experinse. Buy one done and have some fun.










factory as a 2DHT
Title: Re: 57 Convertible rear bow dimension?
Post by: brushwolf on 2026-02-12 14:49
Yeah, it is a lot of work but I enjoy it and will work on these old cars till I drop, though I could afford to buy finished one. A lot of my mechanical and practical repair capabilities were honed doing this cuz I could not justify buying a better one. Now I just prefer the challenge of saving the old stuff. Mine has original frame, cowl top, convertible top frame, upper half of both quarters. Everything else is from another car, or is a repro panel. Doors and trunk lid from a car in North Dakota, 4 speed T10 trans from EBay, repro lower quarters, valance below trunk, floor sections, rear axle, springs and front clip off a 57 Ford Sheriff dept. car from CA. I am in my 70's also, but will keep on doing this until my body won't let me. I was diagnosed with MS a year and a half ago, which may have slowed me down some but hopefully will not stop me anytime soon.
Title: Re: 57 Convertible rear bow dimension?
Post by: brushwolf on 2026-02-12 18:09
Alvin, 22" seems to match a top mfctr provided dimension for bow 4 for these cars of 21 1/2". They use outside edge of 4th bow rather than center of tack strip. Adjust for that, same distance..

Could you also take a horizontal measurement at top center between outside edges of bows 3 and 4 from inside the car? And perhaps the distance between bows 2 and 3 as well? As you know, all 3 of those bows pivot on the ends. Bow 3 ends have a metal stop to keep the bow from going back past a certain point. (See attached pics).

I suspect these stops are not supposed to be all the way back like mine are now cuz I am using a wire tied between 3rd and 4th bow to keep the 4th bow in position. So that pulls bow 3 back against those stops and that hard stop could potentially put excessive tension on top material all the way back from bow 3 to the trim sticks/tack strip down below the rear window.

And I suspect that bow 2 is likely to be positioned correctly when it is midway in its rotational range (making the top of the bow near horizontal if a level were placed on top of it.

Thanks, Mike
 
Title: Re: 57 Convertible rear bow dimension?
Post by: brushwolf on 2026-02-12 23:42
Then again, bows 2 and 3 are not attached solidly to the top, they just have the bars on topside of bow that fit inside the sleeves attached to the top, so they will not put any or much tension on top material itself, just the pads on each side..