Green’s Dictionary of Slang

hammer and tack n.

also hammer
[rhy. sl.]

1. (Aus./N.Z.) a sixpence [= zac n.].

[Aus]Argus (Melbourne) 13 June 4s/3: Here we have the ‘John Dillon’, and [...] ‘hammer and tack’ for ‘zac’ (6d.) and ‘Rhodes scholar’ for ‘dollar’ (5/-).
[Aus]Pete’s Aussie Sl. Home Page 🌐 hammer and tack: a zac, sixpence (obs.).

2. (Aus.) a road [= SE track].

[UK]Dodson & Saczek Dict. of Cockney Rhy. Sl.
[UK]Partridge DSUE (8th edn) 524: A track [...] since ca. 1920.

3. (Aus./US, also hammer and rack) the human back.

[US]A.J. Pollock Und. Speaks.
[US]Baker ‘Influence of American Sl. on Australia’ in AS XVIII:4 256: There’s two Jacks on me hammer.
[SA]L.F. Freed Crime in S. Afr. 106: His ‘hammer and rack’ [is] his back.
[Aus] ‘Whisper All Aussie Dict.’ in Kings Cross Whisper (Sydney) xxxv 6/2: hammer and tack: Back.
[Aus]J. McNeill Old Familiar Juice (1973) 75: dadda: (heaving a sigh) Whew! The screw’s right on me hammer.
[Aus]J. Byrell (con. 1959) Up the Cross 10: ‘[He] crept up behind Awful’s hammer and whacked Awful on the gregory’.
[Aus]R. Aven-Bray Ridgey-Didge Oz Jack Lang 31: Hammer and Tack Back.
[Aus]J. Byrell Lairs, Urgers & Coat-Tuggers 161: Gloaming sat right on Beauford’s hammer and bunged on the pressure just before the turn into the straight.
[US]E. Bunker Mr Blue 114: A ‘bottle and stopper on the hammer and tack,’ means there’s a copper on your back.
D. Shaw ‘Dead Beard’ at www.asstr.org 🌐 My strife grins and nods towards Dionne’s hammer and tack, then waves me forward.
[Aus]N. Cummins Adventures of the Honey Badger [ebook] I knew Kurtley Beale was on my hammer.

4. (Aus.) dismissal from a job [= sack n. (2a)].

[Aus]R. Aven-Bray Ridgey-Didge Oz Jack Lang 31: Hammer and Tack [...] sack (fired from the job).

5. (Aus./N.Z.drugs, also hammer and jack, tack) heroin [= smack n.2 (1)].

[NZ]G. Newbold Big Huey 217: Chris [...] was doing eight for importing coke and hammer.
[Aus]Tupper & Wortley Aus. Prison Sl. Gloss. 🌐 Hammer and jack. Heroin. Rhyming slang for ‘smack’. Sometimes just hammer.
[Aus]Smith & Noble Neddy (1998) 264: I evened the score 10 times over in the near future by leaving them out of three rip-offs that I did for more than six million dollars worth of hammer [heroin].
[Aus](con. 1964-65) B. Thorpe Sex and Thugs and Rock ’n’ Roll 328: ‘They was [...] inta the hammer ’n’ tac long before’.
[Aus]L. Davies Candy 4: What I get from hammer is a kind of deep comfort.
[NZ]D. Looser Boobslang [U. Canterbury D.Phil. thesis] 83/2: hammer n. heroin [...] hammer and tack n. heroin (and the outfit that goes with it: hypodermic syringe, etc [...] 184/1: tack n. heroin.
[Aus] D. Whish-Wilson ‘In Savage Freedom’ in Crime Factory: Hard Labour [ebook] ‘You need water?’ ‘I need Hammer.’ ‘None left’.
[US]‘Dutch’ ? (Pronounced Que) [ebook] He and Shameeq took their hammer game to the next level.
[Aus]D. Whish-Wilson I Am Already Dead 240: ‘I put hammer in your arm, take away your pain’.

In derivatives

hammerhead (n.)

(N.Z. drugs/prison) a heroin addict.

[NZ]D. Looser Boobslang [U. Canterbury D.Phil. thesis] 84/1: hammerhead n. 2 an intravenous drug user, esp. one addicted to heroin.

In phrases

on someone’s hammer (and tack) [rhy. sl. = get on someone’s back under back n.1 ] (Aus.)

1. very close behind, usu. of racehorses.

Eve. News (Rockhampton, Qld) 15 Dec. 7/1: [of a horserace] Young Beo was the early leader, but Afterthought was always on his hammer.
[Aus]Sydney Sportsman (Surry Hills, NSW) 21 May 4/2: Colation clapped on the canvas, and sailed along to the front. Silent Rose was on his hammer and tack.
[Aus]Sydney Sportsman (Surry Hills, NSW) 13 May 4/4: [T]he favorite, Comedy Queen, was on his hammer-and-tack.
[Aus]Truth (Brisbane) 8 Nov. 2/1: ‘[I]t would have been fatal to pull him up and then go on with Shakespeare right on my hammer’.
[Aus]L. Glassop We Were the Rats 140: The Jerries might be right on our hammer for all we know.

2. hounding, pestering.

Nambucca and Bellinger News (NSW) 11 Mar. 2/5: He said he thought he knew who did [the robbery], and he said he would be on his ‘hammer’ to get a cut out of it.
Maritime Worker (Melbourne) 25 Nov. 11/2: The black Panther and Phil Veeny, Hunsword and O’Dane. / They all were on my hammer, and a cracker was the pace.
[Aus]D. Niland Shiralee 37: The child was on his hammer from the moment he woke.
[Aus]P. Doyle (con. late 1950s) Amaze Your Friends (2019) 45: Kevin had been working hot [...] and the cops were on Kevin’s hammer.
[Aus]P. Temple Dead Point (2008) [ebook] You think I’m such a dumb cunt I’m dealin while I’ve got the fucken Feds on my fucken hammer?
[Aus]P. Temple Broken Shore (2007) [ebook] The Commissioner’s on my hammer.