I don't know about "timber rock jigheads" ... but, I've been using Oldham's Surelock Weedless Crappie jigheads for years, and they've worked fine. They're only shortcoming is when the weedguard gets bent up (it's a thin wire loop). I've also been using P&S Custom Tackle weedless jigheads ... brush style. I've pretty much gone to just using them, and using the Oldham's as "backup stock".
Paul Mullins of P&S Custom Tackle can be reached at: [email protected]
He can custom make weedless jigheads pretty much any way you want them.
Paul is a Crappie.com member, and a great guy to deal with.
Oldham's Surelock's only come in 1/16oz - they have a flattened oval head, and the weedguard is a thin wire loop that comes out of the head and slips under the hook point. They are unpainted, and they retail for around $3.50 for a pk of 8 (or something like that ... I haven't purchased any in a while).
Terry Oldham can be reached at: 1-800-596-2436 (he doesn't have a website, that I know of). If you're looking for a jighead for tubes, grubs, etc. ... and you thread the bodies on the hook - Surelocks are the ones you want (he makes several different types, but only two for Crappie ... Speed Loaders & Surelocks. NOTE: Speedloaders are more of an "insert" style head, and are shaped like the big end of a baseball bat. They come in 1/32 & 1/16oz).
I've used both of these guys products with great success ... I throw them on 4-6lb test mono, and with rods from Microlite to Light action rods. 95% of the time I get a solid hookup, with the hook buried in the roof of the fish's mouth. .
If you decide to contact either or both of these gentlemen, tell'em I sent ya !! ......... luck2ya ........ cp