The Idle Pen - The Andrew Turnbull License Plate Gallery

9-7-2009: Demystifying Wisconsin II: Slots and Grooves

The 1967-86 era of Wisconsin license plates is a veritable goldmine for minor die and stamping variations.

Last time around I focused on the "crude die" variation of the 1973 base, but this is hardly the extent of the varieties that exist. Some of these include slightly-different forms and proportions of the state name, slogan, month abbreviation, and serial character dies; although these tend to be so scattered in distribution that I won't even start worrying about narrowing them down beyond rough approximations. A feature that isn't scattered, however, is the series of "groove and slot" stamping variations toward the end of the 1980 base's run.

Most 1980-base plates (and indeed, the 1973 and 1968 issues as well) have a couple of distinctive elements in their composition: A debossed groove below the slogan that leads to the outside border of the plate, and an elongated keyhole-like slot in the lower right corner. (In case you're wondering, the elongated slot never seemed to be intended for the facilitation of mounting the plate to the vehicle, but was rather a "hanging hole" used when plates were dipped in the midst of production. The extra holes on 1942-52 plates and the vestigial "tab slot" on 1956-82 motorcycle plates served the same purpose.)

In due course, these features disappeared. The lower right "keyhole" slot was first to disappear; replaced by an ordinary bolthole by August 1984. The next change happened in 1985: In preparation for the upcoming graphic base, the debossed border on Wisconsin license plates was replaced by a beveled "step" edge, and the groove below the slogan was removed. This proved to be the last change until the yellow plates were succeeded by the graphic issue in August 1986 (although a few yellow plates were remanufactured as replacements even after that). Natural 1986 and 1987 expirations can appear on both of these late variations.

[Groove and slot] [Groove and no slot] [No groove or slot]

These are the "groove and slot" variation cutoffs for each month series that I've observed so far. As always, I'd be curious if any reader happens to have a plate on hand that might narrow things down even further!

	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Groove and slot	AP 9484	CR 1110	EX 1584	HA 4355	KC 3913	LX 5770	NV 1736	QX 9909	SP 5035	US 2759	WJ 2606	YF 7653
Groove and no slot	AT 2685		FD 8864 FF 6916	HC 8704		MD 3154 ME 3399	PB 6968 PD 3036	RA 1460 RF 2752	SV 7638 SZ 8311		WM 5023 WN 7505	YK 4501 YN 3934
No groove or slot		CZ 4206 CZ 9451		HD 4770 HM 4075	KM 1428 KP 6401	MK 6660 ML 5938	PF 3444 PK 3449		TC 4352 TE 3613	UZ 1609 VB 6684