I saw one of these at Lowe's the other day and was just wondering what the pointed end is used for. I have seen it called a "construction" wrench and a "spud" wrench.

Construction Wrench

  • It is also known as a podger (podgering) spanner or spike.
    – user42013
    Commented Aug 31, 2015 at 16:57

5 Answers 5


Same thing you use a Marlin Spike for. (Tapered steel rod with a mushroom head on one end to strike with a mallet or dead blow) It's an alignment tool for drilled holes in metal building frames.

During assembly, the bolt holes don't necessarily line up, so you stick the tapered tail through the mating holes in the construction item, lever them around till the adjacent holes line up, slap a bolt through, affix a nut and washer and then use the wrench end to tighten.

Note: Landlubber term is Drift Pin or Bull Pin. Alignment Punch would be the technical name any machinist or mechanic would recognize. When an ocean going tug captain decides that it's more lucrative to run his boat up a slough, pull the engine and use it to power a sawmill operation, he's already been using a tapered steel rod to splice hawser cable. And when he needs to line up pieces of equipment on shore, he repurposes the Marlin Spike for more or less what he's been doing with it all along, using it as a multipurpose prybar, alignment tool and general persuader of anything that isn't quite in the right place. And the name he knew it as followed him into the big mill where he became head millwright.

  • I think you mean Drift pin.
    – Tester101
    Commented Oct 10, 2012 at 11:45
  • 1
    @FiascoLabs - Excellent answer. A tool like this is often most useful when the two parts being aligned have more than one set of holes. The tool aligns from one set of holes whilst the first bolt(s) are are slid into another set of holes.
    – Michael Karas
    Commented Oct 10, 2012 at 11:47
  • 2
    I've only ever heard the term "marlin spike" used in reference to a tool used to splice rope and untie knots. I think the tool that @FiascoLabs refers to is known as a "drift pin", "bull pin" or "alignment punch", which is bascially a spud wrench without the wrench
    – mac
    Commented Oct 10, 2012 at 20:32
  • Don't know whether it's a regional thing or because some of my relatives worked around a marine environment and misappropriated it, but that's what my millwright uncle called them. Drift or bull pin are terms I've heard used as well. Assembling sawmill equipment requires gently easing heavy, somewhat uncooperative things into place so they're a much used tool there. Commented Oct 11, 2012 at 2:12
  • Bull and drift pins are construction tools, for aligning(as everyone stated priorly above). While you can use a marlin spike this way, it's like using a pliers to hammer a nail. Marlin spikes are a wire cable splicing tool. The wooden equivalent is a fid, and is used to splice rope (manilla & hemp etc) as opposed to cable. Commented Sep 6, 2015 at 15:26

I'm an ironworker and we use the "bull pin" to hammer into points and then bolt up, we use a "sleeve bar" or alignment bar to move the point around line up holes and then bolt up usually while still holding the s leever bar, when you use a bull pin you can go hands free because it is wedged into the point. A marlin spike is far to small and fragile to be used for any type of bolt hole alignment, a marlin spike is used for back splicing wire cables to make chokers, and sometimes as a center punch in a pinch. And all of our other tools have the pointed end to help with alignment but also so we can set them somewhere safe when we are working thirty stories in the air, wedged in bolt holes;-)

  • Sleeve bar, brings up another term I've heard to describe extra leverage called is a "Swede Pipe" or "Swede Bar". I see this really big, blonde guy pushing the wrench with his little finger, everyone else needs an extension. Commented Feb 23, 2014 at 2:44

I was the Shipsboatswain (Boson) on the USS Forrestal (CV-59) and I carried one of these Adjustable Marlin Spike wrenches along with my knife and sheath on my side daily. Walking around the decks I was always stopping to tighten something that was loose, whether it was a bolt, nut, or wire rope. It was also my hammer for shackles and sheave pins. It was very handy to hold a piece of flat bar from getting underway etc... I still have mine in my tool chest in the garage. I never thought I would see a Picture of it here. I thought I was the only one with an original idea. I even got to use it on an aircraft, when the airman did not have time to check out the tool from the tool room.


It's a spud wrench. You use it to align holes while connecting steel beams together. Align the holes with your wrench, if necessary using a sleever or connecting bar, stick your spud wrench through the hole. Nothing fits as perfect as it's drawn, so you stick the point in the hole until it's deep enough where you can make a bolt in a different hole. Screw that bolt down, stick another get to the hook and go.


Whatever you might prefer to call this type of wrench, it comes in many sizes due to the almost universal need for a tool to perform its intended purpose.

As the preceding posts point out, the tapered "spike" or "pin" end is very useful for aligning holes to allow the insertion of pins, bolts, rivets, or any thru-hole connector. The spike also allows you to slide a "cheater" pipe over the end of the wrench to provide extra leverage so you can apply more torque at the wrench-end.

I have used these tools to align the mounting holes in many types of equipment, ranging from installing military Surface and Air-search Radar assemblies (Remember, boys...Heads UP, Nuts DOWN!) to aligning the bell-housing of a farm tractor transmission to the engine block, and even when aligning mount holes for rack-mounted electronics.

Assuming you have the proper size of this tool, you can find a use for it while working on almost anything.

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