What wrench for an M20 Bolt?

[Jim Fox]

Need to undo a M20 Bolt and Nut for my Bandsaw Riser.......how in the heck am I going to do that? Do they make a wrench for that? I tried my crescent wrench, but not enough room to turn.

Suggestions?

[Chris Padilla]

http://www.imperialinc.com/pdf/A_CapScrewHeadWrenchSizeChart.pdf

:D 30 mm! Can you get a socket on it?

[Bob Vallaster]

If you don't have the metric set, a 1 3/16" socket-or-wrench will do.

BobV

[Jim Fox]

http://www.imperialinc.com/pdf/A_CapScrewHeadWrenchSizeChart.pdf

:D 30 mm! Can you get a socket on it?
I'll have to get a open ended wrench for the head and a socket for the nut.

[Jason Roehl]

I've been wrenching on my own vehicles for years. I don't know what an M20 bolt is (I suppose I could look it up). But, what I can tell you, is when it comes to bolts and nuts in an automotive situation, it is all about extensions and u-joints. Get the socket on the bolt or nut, then use extensions and universal joints to get out and away from the fastener so you have room to turn the ratchet without busting your knuckles. A lot of times, if you have to hold a nut while turning a bolt (or vice versa), you can wedge a box-end wrench on the nut up against something nearby while you put the socket on the bolt.

Oh, and if you're going to put a socket on it, make sure it is the right size, especially if it is a 12-point socket. 6-point sockets MIGHT let you get away with mixing SAE and metric, but a 12-point will ruin your day. DAMHIKT.

[Howard Acheson]

For all dealing with this thread, "M20" means it's a metric (M=metric) bolt with a 20 mm (millimeter) nominal diameter. In other words, it's a big bolt and will require a metric wrench or socket of appropriate size.

I'm not home now to check it out, but you may have to go to a mechanic and see if you can borrow a wrench of the proper size.

[Rod Sheridan]

The standard wrench size for an M20 bolt would be 30mm, however 32 and 34 are used for M20 Heavy bolts under DIN/ISO standards.

Measure the bolt head, then head off to Sears or anywhere that sells tools and purchase a socket and wrench.

Regards, Rod.