OK back with a little more info for ya....
"In 1935, Gibson started making another in-house budget brand called Cromwell. Unlike the Kalamazoo brand, Gibson hid the fact that they were “Gibson� made, opting for phrases like “Guitars By Master Craftsmen� . The two largest distributors of the Cromwell line were Continental Music in Chicago, IL and Grossman’s Music in Cleveland, OH. Both were also big Gibson distributors and Gibson wanted to maintain the “Gibson� name as the best brand (and most expensive), while offering the Cromwell line as a separate brand name. Kind of like Michelin making all Sears-brand tires. Cromwell was basically GIBSON'S house brand. The idea was to have a line of guitars that could be sold by jobbers (large musical instrument distributor that carried many brands) to music stores who weren't franchised Gibson dealers and couldn't get Gibsons and Kalamazoos. The majority of Cromwells were sold by Continental Music (owned by C.G. Conn, the band instrument manufacturer), with others such as J.W Jenkins (a large mid-west Gibson dealer in Kansas City), as well as Coast Wholesale, and Gretsch & Brenner (not to be confused with Gretsch Guitars).
The G-2 flat-top is quite rare and few exist making them more valuable. The arch-tops G-4 and G-6 were the most popular, and many examples still exist, and not as valuable. In 1936, the Model G-8 was introduced as the top of the line, but the much higher price hurt sales, and was discontinued soon after., and makes it one of the most valuable and collectable Cromwells. The difference between the models was based on the Model number (low to high). The G-4 was the least expensive; the G-6 had an inlaid logo and fancier black & white checkered purfling (similar to the Kalamazoo KG-32). All had Gibson tailpieces, but usually Grover-made pickguard brackets and the most recognizable feature all the Cromwells, besides the large stenciled logo on the peg head, was a white stripe running down the center of the fingerboard. Most experts agree that Gibson probably made the Cromwell brand starting in early 1935, but stopped sometime in late 1938, or possibly early 1939."
You can find more, including photos, at the website:
http://www.fox-guitars.com/Gibson-Made_Brands.html
The only correction I'd add to the above is about the white stripe running down the fretboard... While it's very common on Cromwell's, it's not on all of them. I've seen several examples with dots and a few with block inlays...
As for value.... It's hard to say cause of condition and not knowing the exact model but I'd "GUESS" 6-7 hundred for the lower end models and more as you move up their line. There's a lower end model on Atlanta's craigs list now for $950...
Now for the repair.... It's hard to say for sure without pics but most splits can be repaired quite easily.. Humidity will often close the crack and glue can be injected and it cleaked from the inside to stabilize it. Being on the back minimizes the harm on resale, as a back crack has almost no detrimental affect on tone....
Funny thing for you to post this... I was just reading up and researching the brand a few weeks ago
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