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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
456 Reviews
5 Stars
4 Stars
3 Stars
2 Stars
1 Star
Perfect for small tight spaces.
June 29, 2020
1 month ago
Woodworking Experience:
Nice and thick for clamping.
June 29, 2020
1 month ago
Woodworking Experience:
Clamp-It Square
I purchased two of these squares years ago and they got lost in the back of a drawer (along with the clamps). A couple of months ago I needed to use a couple of square and clamp assemblies just like them, found them, and they performed flawlessly. I absolutely love them! I wish I hadn't lost them in a drawer so long ago. I've since ordered 2 more and use them daily.
June 15, 2020
2 months ago
Woodworking Experience:
Rockler squares
Had some older ones but these are replacements worked great for project to hold everything at 90
June 9, 2020
2 months ago
Woodworking Experience:
Product performed as stated
June 7, 2020
2 months ago
Woodworking Experience:
I really should have gotten these years and years ago. Can be used on so many different projects. Sturdy, lightweight, and most importantly MADE IN THE USA!!!!
June 3, 2020
2 months ago
Woodworking Experience:
Excellent product
May 31, 2020
2 months ago
May 19, 2020
8 months ago
Woodworking Experience:
Making square corners
I am making some carts for a few shop related tools I am going to have on the Rockler All-Terrain Mobile Base. I need the corners of the carts to be square. Using the Rockler Clamp-It Corners makes this a simple task to perform.
May 18, 2020
2 months ago
Woodworking Experience:
Keeping project stable
I have found these clamps very useful. I do a lot of wood projects and I have several of these.
May 15, 2020
3 months ago
Woodworking Experience:
Start typing your question and we'll check if it was already asked and answered. Learn More
Browse 8 questions Browse 8 questions and 62 answers
Why did you choose this?
Rockler Store
I am hoping these will help me keep cabinets and drawers square during glue-up. I have had issues with that in the past.
Jerry B on Jul 2, 2020
because you need it for the corner jig
Randy H on Jun 17, 2020
I am hoping these will help me keep cabinets and drawers square during glue-up. I have had issues with that in the past.
Jerry B on Jul 2, 2020
Great Value
DAVID G on Jun 17, 2020
because you need it for the corner jig
Randy H on Jun 17, 2020
make perfect 90 degree joints
ROBERT D. on Jun 17, 2020
Need something square for glue-ups.
Joshua S on Jun 16, 2020
who doesn't need a square?
Robert S on Jun 15, 2020
building cabinets and it pairs with the Corner Clamping Jig
Michael P on Jun 10, 2020
Simple yet handy tool for wood working projects
Jack on Jun 8, 2020
It has the option to attach the fence clamps instead of just regular clamps.
Adam Y on Jun 8, 2020
fathers day
David K on Jun 6, 2020
I need help building boxes that are square
James P on Jun 5, 2020
Ordered the clamps separately and now need the corner square. Was confused by the catalog description and thought I was receiving both.
Eugene B on Jun 5, 2020
Cabinet Project
Curtis M on Jun 4, 2020
Because you mislead me when buying the clamp jig showing these in the order. You are better than that ☹️
David R on Jun 2, 2020
Square drawers
Sean B on May 27, 2020
I need this attachment for the rockler clamp it jig
Brian on May 27, 2020
Perfect for the project I’m working on.
JAMES R on May 25, 2020
have one, need another
Russell G on May 22, 2020
Because they don't come with the Rockler Clamp-it and you need them to make it work! I will not need them if they come with the Clamp-it kit.
Edward A on May 21, 2020
I thought it came with the jig which I just bought
Mike on May 8, 2020
Put draws to toghther and keeping thinks square when putting them toghther
Chip on May 8, 2020
Looks as though it will help free up my hands
Philip A on May 1, 2020
have one set already and found to be very useful and easy to use. great 90degree corners
Ron A on Apr 30, 2020
Have 2 need 4 for making 90 degree corners
Judy A F on Apr 30, 2020
Needed this for my Clamp it corner clamping jigs.
Michael F on Apr 30, 2020
I needed this for many projects
TAW on Apr 30, 2020
To complete my set for a total of 4
William R on Apr 29, 2020
You need this for the corner clamping jig
steven l on Apr 29, 2020
Using to help glue up drawers.
Dave D on Apr 28, 2020
To assist with assembly.
Timothy C on Apr 27, 2020
To ensure that my corners are square while building my workbench.
Jerry A on Apr 26, 2020
Had one found out I need two at least
Richard G on Apr 26, 2020
Already have a couple love the way they work
Ralph I on Apr 25, 2020
Great for assembly
Ron K on Apr 24, 2020
Ease of use
Michael M on Apr 24, 2020
Building a custom bookshelf soon. Your video made it look easy.
Richard C on Apr 24, 2020
Saw something similar on you tube
Alan Andersen L on Apr 22, 2020
I need it
Richard B on Apr 22, 2020
Need it for the Jig.
THOMAS K C on Apr 21, 2020
cabinet making ease
Cory E on Apr 20, 2020
need them for next project (cabinets for the garage)
Thomas E on Apr 19, 2020
I bought these to install onto the corner clamping jig.
R.A. K on Apr 19, 2020
Looks like a perfect fix for framing
STEVE R on Apr 19, 2020
I am building cabinets.
Hannah S on Apr 18, 2020
I need my projects to be square.
Jason P on Apr 17, 2020
Have one, needed two.
Wally G on Apr 16, 2020
This will help with keeping projects square during assembly.
Craig on Apr 16, 2020
because i ordered the mini squares and there too small for the clamps!
James C on Apr 16, 2020
Better quality than the square's I am currently using.
William P on Apr 14, 2020
handy for clamping corners
michael g on Apr 13, 2020
Great Value
DAVID G on Jun 17, 2020
make perfect 90 degree joints
ROBERT D. on Jun 17, 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
How do you hang these on the wall so they don't get knocked off?
BG on Jul 3, 2020
BEST ANSWER: I don't put them on the wall they are in my drawer with my other special clamps.u could put them on the wall Just use your imagination
My assembly squares are a few years old. The screw holes don’t line up with the holes in the corner jig. Is this true or am I just a big noob?
Jac C on Apr 5, 2020
BEST ANSWER: Mine were actually out of square slightly, so I had to square them up with my miter saw. I still have mine but they don't work as well as the Anodized Aluminum ones from Woodpeckers. Now THOSE are perfect. Plastic, nylon, poly, whatever, can all get off kilter. Solid Aluminum bar stock doesn't.
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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