How to Use a Speed Square

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Ask This Old House general contractor Tom Silva demonstrates the amazing versatility of the humble rafter square.

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Shopping List for How to Use a Speed Square:
– PVC baluster, used to make Speed Square holder
– 3/4-inch plywood strip, for reinforcing PVC baluster
– Short screws and belt clip

Tools List for How to Use a Speed Square:
– Speed Square
– Miter saw, to cut PVC baluster
– Table saw or router, for slotting PVC baluster

Steps for How to Use a Speed Square:
1. A Speed Square, also called a rafter square or layout square, has a 90-degree marking edge and a 45-degree marking edge.[BR]
2. The square can be used as a straightedge guide when crosscutting with a circular saw.[BR]
3. A pivot point allows the square to be used as a protractor for marking angled lines.[BR]
4. The square is ideally suited for laying stud locations for walls.[BR]
5. Built into the square are several scribing notches, which provide a fast, easy way to mark layout lines or cutlines onto lumber.[BR]
6. The perfect 90-degree corner of the Speed Square can be used to determine whether two boards form a precise right angle.[BR]
7. To keep the square close at hand, hang it on your tool belt with a hook or get a specially designed Speed Square pouch.[BR]
8. You can also custom-make your own Speed Square holder from a PVC baluster.[BR]
9. Cut the baluster to length on a miter saw, then cut a stopped slot along one side with a table saw or router.[BR]
10. Cut a [FRACTION 34]-inch-thick plywood strip to fit inside the PVC holder, and secure it with short screws.[BR]
11. Attach a metal belt clip to the opposite side of the holder.[BR]
12. Clip the holder onto your tool belt, then slide the Speed Square into the slot.

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Deranged Chicken says:

great info on the rafter square – something you never mentioned – i love using mine for taking a 90 or 45 around a corner – ie side face to top face. you have to blag it with any other square. its a great precise piece of field equipment

Life Is Timeless! says:

Best wood porn I’ve seen to date!

mixwell1983 says:

Tom Silva is a fucking master! My grandpa was a cement mason primarily and general contractor. I wish i was older or my grandpa younger to learn some tricks. The days of “men” are dying out. We need more young people into the trade and off of their fucking phones.

theresa baker says:

I am left handed and petite, what would be a good choice for a circular saw for me?

Jens Oliver Murer says:

One day the world will ask for the best clip on the internet and I‘ll vote for this one.

Ron JL White says:

god i love these guys. Norm is my idol but the entire crew has been useful as well!!!

m13taylor says:

Hey Tom. That’s not what the diamond cut out is for. It’s to mark seat cuts on common rafters. Only on Swanson. So original it’s Trade marked. You probably noticed how the speed square does not lay flat if you try to use it as a 90 degree square for the seat cut, hence the diamond.

Tome4kkkk says:

3:10 Wait, what? A 2×4 is 3.5 inches wide?!

Skyler King says:

From the 2:00 mark to the 2:10 mark, the piece of wood he is demonstrating on changes. Makes me wonder what magnificent blooper we’ve been deprived of…

John Dickerson says:

one of my favorite tools to !

Chelle Weatherspoon says:

Wow! I have one of those and I use it all the time but never knew I could use it this way. This is going to help me tons. Thank you so much for sharing.

gteea says:

I havent carried a mitre saw for months to jobs. Ive used my speed square and saw. I use a clamp to get mitres. Works a treat

Jafar Martin says:

This is a great channel.

Fabuloso says:

Thats fab

Jay Nielsen says:

I went on a tool spending spree a while back. This was one of the tools I grabbed; had no idea of it’s potential.

tim richter says:

he marked his 16 on center layout wrong….

Marticulate says:

Great video. You’re just inching your way to millimetres :)

Steel Here says:

Tom pulled out his speed square as if it was a gun. “A good guy with a speed square.”

Nathan Heeren says:

22 and a half is one quarter of 90.

Poopy Pants diggity says:

Rep the Swanson

Danny Taveras says:

U should consider make your own channel on how to use these tools roger i learned more in 5 sec with u then most an a hr…thank

Dean Raynor says:

They are only good for scraping ice…thats it

John Dickerson says:

I carry it in my back pocket

Ezay Hayhay says:

I don’t need a square but now i want one !

Dicky Ball says:

Good Job, Tom.

snipers dream says:

he didnt mention finding angles, one its main uses. apart from that great vid.

A_Sensible_Young_Man says:

My aunt is secretary of the caravan club.

Jack Reeves says:

Most used tool in my woodturning shop!

Billy Garfield says:

Great idea for a speed sq holder!

Nick Michels says:

They should do a this old house 3D printer segment and make Tommy a set of new speed square holders.

AdrianJayeOnline says:


james nichols says:

demo square cut, cuts crooked. lol

therealknapster says:

3.30 missed out on a game of naughts & crosses 😉 and game on , being one square already in play :)

crb129_ says:

Good stuff

Lazaro Nogueira says:

Tom Silva vs Bob villa drop the mic

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