Corner Clamps





Introduction: Corner Clamps

About: For several years with my daughter we have been building interesting appliances in a small garage, you can visit us and build something with us.

The clamps shown above are designed to hold the elements glued at an angle of 90 degrees. We often come to stick together different types of enclosures for our devices. Same carpentry clamps or clamps holding the elements from the outside unfortunately not always enough. We decided to make a set of corner clips that will help keep the corners straight when gluing the side walls of boxes and boxes.

An example of how to use Clams are shown in the second photograph.

Step 1: Designing

We designed our Clamp in Sketchup 2016.

Drawings along with the vector file SVG (for CNC milling machines) can be found in STEP 4. Dimensions of the side walls are 150x150 mm. To prevent gluing of the clamp to the glued elements, we made a corner cut at 45 degrees to create a place for the glue to emerge during clamping.
I mentioned SVG file for CNC milling machine. The file was exported from Sketchup using a plugin named FlightOverIdeas. The plugin allows you to export vector files with marked surfaces, which makes it very easy to work with a CNC milling machine.

Step 2: Preparation of Elements

The components of the kit consisting of four clamps were made on a CNC milling machine. We used plywood thickness 18mm for individual parts. Actually, they were small waste left over after another project, waste that has gained new live.

Nothing prevent you to make the elements manually using typical tools, ie saws and drills. The drawings we mentioned earlier also contain a dimensional drawing. Units are in mm.

Step 3: Finishing

Four Elements were cut. First, you need to roug an element by 120 grit sandpaper. Then finish with graduated paper 180 and 220. We gently roughened all the sharp edges remaining after cutting with a milling machine.

Prepared parts will be cover with dark hard wax oil.

Hard wax oil will be applied with a properly prepared cotton cloth. Actually, it's a simple tampon.
The Tampon is made up of several cosmetic flakes wrapped in cotton (our cotton slice comes from a torn T-shirt)

The flakes are wrapped in cotton and then crimped to form a resilient cushion.

Apply oiled oil evenly along the edge of the clamp.

Step 4: Job Done :)

After applying the first coat, let the clamps dry. Depending on the type of wood you have to apply two or three layers until you are satisfied with the end result.W

NOW - This is that moment when You should CLICK VOTE in the right top corner of your web site.

Little Edit: I add Sketchip file. It has been made in SketchUp 2016 so if you will open it you will need to have v2016 or 2017.



  • Make it Move Contest

    Make it Move Contest
  • Oil Contest

    Oil Contest
  • Casting Contest

    Casting Contest

We have a be nice policy.
Please be positive and constructive.




No problem at all, People should help each other ;) MountainMan. I would suggest deleting your email address from the common view. If you need something else, just write on Priv. I forgot to say plywood for your clamps should have 1/2 inch thiknes. (aprox)

2 replies

How do I get into my replies/postings to either delete them or edit them???

I"m afraid you will need to delete post and write new one in place of this deleted

Много хубава идея.

Ще си ги направя ръчно защото нямам ЦПУ.

Благодаря за чертежите


1 reply

Sorry to say but your download link to the files is not working. Everything I try clicking gives some sort of Google error and I can't read the responses because they are in a language I can't read. Can't you attach them here?

3 replies

Sorry to hear that, but you are right. Thank you very much for info. This has working since day one over google translation system, now is not any more. I made correction. Files are attached at the End of this Instructable. Thank You one more time for information, I would apologize for download problems.

Dear silveravnt on your reqest SKP has been just add by the last step. My SketchUp ver. is 2016 so you need the same or higher to open it.

Thanks, No I mada export to svg Vector file is ready to be open in CAM software for CNC milling.

Nice job! Sort of in the "now why didn't I think of that?!" class.

Some constructive suggestions?

1. Make the hole in the corners square and minimize the radii of the corner fillets. The way you've done it looks very pretty but could limit the size of clamps you're trying to get in there. When clamping up a mitre you want to get the pressure points as close into the corner as you can...

2. I would put a small chamfer on the outside edges. Can't really say why but I have a feeling it would be a good idea... It will look nice?

3. Using plywood is a good idea because it gives strength in both axes and you don't have to worry about grain splitting in tension

4. Getting the outside corners exactly 90° and the edges exactly square to the faces without a CNC could be a challenge. But nothing that a half hour or so armed with a good sharp block plane won't sort out..

5. The Vote button is at the BOTTOM right ??. Almost missed it

1 reply

Thanks, a lot, I will get your suggestions in next set of holders for sure. I made in on CNC becouse they was urgently needed. As you have see on the second photo ( example of usage ) when I use them they wasn't still painted with the wax oil. Getting 90 degrees is possible also if you have table circular saw, I got small Metabo and it will for sure be very helpfull in case of manual holders production. Thanks for you Vote Click ;) yes it's this green in the bottom ;)

So much overkill, but then I guess that is the thing of the times.

Not sure why solid modeling is required here, but CAD is so cheap anymore that why not. Even a drafting board T-square and a few triangles will get the job done

I stick to TommyCAD for my 2D work with an occasional ISO for added "touch". Just a as using a drafting table.

For solid modeling I use TurboCAD, or if I really need to get fancy, I'll utilize SolidWorks. Then I can utilize onboard FEA for stress/deflection analysis

Just an old guy just wondering and rambling on.

Nice though, even with all of the work and expense involved, i.e solid modeling and CNC

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I must say true, I'm total "green" if we talk aboud cad software. Sketchup give me such freelance and from first usage ( I think it was ver 6 ) I'm in love with it. Mostly I make drawings for my 3D prints, so I can say this is my native environment. Making this drawings take me 10 minuts together with export to SVG, really no Overkill at all.

I make frames out of used lumber and have been having a hard time getting a nice joint. The jig I made is used on the outside, but I like this idea bettter. Well done!

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Thank You Very Very Much. Is real nice to read that.

Usage is shown in the second photo: