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$12.99 Each
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Clamp-It® Bar Clamps sold separately
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Rockler Clamp-It® Assembly Square

Align it, clamp it, and fasten it to get perfect 90° angles every time!
Item #
88% of 100
Here's a solution that's so simple, you'll wonder why it took so long to develop! The Clamp-It® replaces custom clamping jigs, acts as a third hand, and eliminates the need for long bulky clamps. Simply put, the Clamp-It® is a square you can clamp. In fact, you can even assemble a cabinet one corner at a time! Works with any joinery technique, from nails to hand cut dovetails.

It's ideal for every stage of construction, from assembling plywood cabinets to face frames and drawers. Clamp-It® is also perfect for framing decks and installing rails and balusters. Attach it to a work surface, and it becomes a right angle fixture for bench assembly. Clamp-It® is computer designed and manufactured from high impact, rigid polycarbonate to ensure strength and accuracy. Size of the Clamp-It® is 8" X 8" X 1 - 1/2".

Great for:

  • Drawer Assembly: Clamp-It® is designed for use on either the inside or outside of a corner, making it ideal for assembling drawers with lipped fronts.
  • Deck Rails: Use Clamp-It® to hold deck balusters at a perfect 90° angle while fastening.
  • Bench Jigs: Clamp-It® can be secured to any work surface to create a simple 90° assembly jig.
(1) Clamp-It® Assembly Square
More Information
Brand Rockler
Weight 0.8000
Length 8"
Style Square
4.4 / 5.0
437 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
90 degree angles
Love these - helps greatly for routine “box” construction
March 20, 2020
1 year ago
Woodworking Experience:
Quality product.Worth the money. I have two and will probably buy another when they are on sale.
March 12, 2020
1 month ago
Rockler Clamp-It® Assembly Square
Used this along with clamp jig to hold shelves to uprights for pantry cabinet. Worked as advertised.
March 4, 2020
1 month ago
Woodworking Experience:
Great for drawers and lots of other applications.
These are very handy. I use them any time I am wanting a quick way to clamp 90 degree corners. They are great for assembling drawers.
February 27, 2020
1 year ago
Woodworking Experience:
90Degree Square
Easy to use
February 22, 2020
1 year ago
Woodworking Experience:
Clamp-it Assembly Square
I bought one a few years back, It works great for squaring up projects during assembly. I bought this one to help larger projects.
February 20, 2020
2 months ago
Works great.
February 8, 2020
2 months ago
Woodworking Experience:
clamp it assembly hinge
I already had two but since they work so well I felt I could use two more.
February 6, 2020
2 months ago
Woodworking Experience:
Terrible boomerang, good square
Cool and useful. Will eventually get more.
Will this stop the emails?
February 2, 2020
3 months ago
Woodworking Experience:
Clamp it assembly square
Bought one a couple years ago with face clamps, then bought a corner clamp it to go with it, then bought 3 more and 3 more corner clamps. All work well and do what they are supposed to. Very pleased
January 19, 2020
3 months ago
Woodworking Experience:
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Browse 6 questions Browse 6 questions and 60 answers
Why did you choose this?
Rockler Store
It got good reviews. Thought I would try it out.
K P on Mar 18, 2020
building tack trunks
kenneth t on Mar 9, 2020
It got good reviews. Thought I would try it out.
K P on Mar 18, 2020
Have 2 and need 2 more - forgot originally there are four corners to a square
Tony V on Mar 16, 2020
building tack trunks
kenneth t on Mar 9, 2020
a good partner for my clamp-it system
michael f on Mar 8, 2020
saw the girl on youtube
Mark on Mar 3, 2020
Makes squaring up cabinets during assembly much easier
Kurt A on Feb 29, 2020
I have one and use it all the time, I like these because of their size, easy to square boxes, drawers, or anything else that is 90 degrees
Charlie C on Feb 27, 2020
John P on Feb 27, 2020
doing a project soon where square corners will need to be precise.
Luke S on Feb 25, 2020
Could not find corner clamp for stock wider than 3 inches.
Tom Ligon I on Feb 24, 2020
clamp, glue and screw drawers
Patrick P on Feb 22, 2020
Extra hands to assure square corners for assembly and glue-up.
Ronald G on Feb 22, 2020
Daniel H on Feb 21, 2020
cost less than woodpecker brand
Chris A on Feb 20, 2020
Building three medium treasure boxes as gifts.
Dana G on Feb 20, 2020
Quality and craftsmanship.
Michael L on Feb 18, 2020
I've used metal right angle rulers to help establish 90 degree angles but the thin ruler makes it more difficult to stay true. The thick depth and affordable price makes this a must see :)
Paul P on Feb 18, 2020
Larry on Feb 18, 2020
future project
Michael H on Feb 18, 2020
Quality of life in the workshop improvements!
Jonathan R on Feb 17, 2020
Needed to accompany the clamp it system
Lillian H on Feb 15, 2020
Don't know if you can use the corner clamps without this?
Angel W on Feb 15, 2020
Interesting idea I want to try.
Kevin B on Feb 15, 2020
building cabinets
Ed K on Feb 14, 2020
Quality assurance during box/crate production.
Jeff H on Feb 11, 2020
Needed for better clamping
Adam R on Feb 10, 2020
using this with my armor fixture table as a square setup fixutre piece
Ken B on Feb 8, 2020
Same as above
Larry on Feb 7, 2020
Work cabinets build
Beau S on Feb 2, 2020
For box building
Gant E on Feb 1, 2020
I thought I ordered this on my last order and you sent me the mini clamp. The phone number 800-376-7856 doesn't work.
Roger R on Jan 31, 2020
To be used with the corner clamping jig
Richard H on Jan 31, 2020
I need them to go with my Clamp-it Corner Clamping Jigs. I missed that note on my first order!
Mike H on Jan 30, 2020
Works in combo with corner clamping jig.
Mark A on Jan 30, 2020
good price
Bruce M on Jan 29, 2020
Build a lot of boxes and cabinets. This looks to simplify.
Allen M on Jan 29, 2020
Already have 2, needed 2 more
Jerry R on Jan 27, 2020
This completes my corner clamping set of 4! Love the corner clamp it system.
Matt W on Jan 27, 2020
Been putting off purchasing this for a year or more. Great videos.
Joseph D on Jan 26, 2020
Have 2, needed 2 more, they work.
Steve R on Jan 26, 2020
I saw a demo of these at a wood working show and thought they would be very useful.
Jeffrey D on Jan 25, 2020
Had two, needed two more, they work so good and easy.
Phillip N on Jan 25, 2020
This completes my set of four.
Jack on Jan 24, 2020
I saw April Wilkerson using this on YouTube looked to be an very helpful product.
Robert L on Jan 23, 2020
because it works with the above.
Al S on Jan 23, 2020
I thought this should have been included with the corner clamp-it jig. It wasn’t so I added to my order
Robert D on Jan 22, 2020
I plan on building a set of upper cabinets for storage in my workshop in the near future.
Jason D on Jan 22, 2020
To pair with my corner clamp.
Mark O on Jan 21, 2020
incase need quick square check
Lee H on Jan 20, 2020
Build a new woodworking shop
Goldawg on Jan 20, 2020
Have 2 and need 2 more - forgot originally there are four corners to a square
Tony V on Mar 16, 2020
a good partner for my clamp-it system
michael f on Mar 8, 2020
When should I use the Clamp-it Corner Clamping Jig vs. the Clamp-it Bar Clamps?
Jerry on Apr 28, 2017
BEST ANSWER: I work for Rockler. When the material is over 2" wide to be clamped, use the bar clamps. I fit is under the clamping jig works very well.
How many are in a package?
A shopper on Jul 29, 2015
BEST ANSWER: Just one. Clamps must be purchased also. Other clamps will work.
What are its complete mesures, 8"x8"x1.5"x?"...?
Carlos Otto C on Jun 21, 2018
What thickness of stock will this accommodate?
Ian L on Apr 14, 2019
BEST ANSWER: You can use this with any thickness of stock as long as you have a clamp that will open wide enough to clamp to it. If you are planning on using it with the fence clamps from Rockler you are limited to about 2 inches of thickness. You can also screw this to the stock which also allows for almost any thickness. It will usually support stock that is of reasonable size. I think I have used these to support 2.x4x3/4 inch plywood panels when making a set of shelves for my shop.
Does the screw holes line up to the holes in the clamp-it corner clamping jig ?
Larry K on Jan 16, 2019
BEST ANSWER: Yes, and the jig comes with the screws you need.
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