Assembling MDF at a 45-degree angle

[ricebridge]

Hello! Today's challenge: Two 19mm MDF boards, just over two meters long, need to be fastened together along the long sides at a 45-degree angle, so that they hold well. But how? Ideally, I don't want to rebate/groove any of the long sides. Since they are so long, it becomes difficult to make it even. I've been looking for construction brackets with a 45-degree angle, but they don't seem to exist... Any suggestions? (It's going to be a pantry in a corner of the kitchen.)

 

[slacker]

An average of 22.5 followed by a number of smaller Domino pieces and glue solves the problem brilliantly. A Festool Domino can be rented or perhaps even borrowed if you don't own one yourself. A biscuit joiner/plate joiner could also do the job using the same principle.

Haven't personally tried Meec Lamellfräs from Jula, but in principle, it should be able to be used for this without any issues. It might help to cut a couple of angles from scrap material at 45 degrees and use them as glue support.

 

[ricebridge]

An average of 22.5 followed by a few smaller Domino pieces and glue solves the problem brilliantly. A Festool Domino can be rented or even borrowed if you don't have one yourself. A biscuit joiner/plate joiner could also do the job with the same principle.

Haven't personally tried the Meec Plate Joiner from Jula, but in principle, it should be able to be used for this without any issues. It might help to cut a few angles from scrap material at 45 degrees and use them as glue supports.

Thanks for the response, but now take it easy and remember that I'm an old amateur. Domino pieces? For me, those are the ones you stand upright and then push over. Biscuit joiner, isn't that something you'd find in a bakery?

Please tell me more as I'm not familiar with either...

 

[vanpire]

Slackers solution should work perfectly, but if you don't have a saw for the long cut or a Domino/biscuit joiner, it's difficult.
What should it look like on the inside?
Two battens, one split into a triangle shape (available at the hardware store, I don't know what it's called) and a regular one are glued together at 45 degrees. If you attach it to the inside of the MDF, you're all set.

 

[ricebridge]

- By the way, how silly of me, the joint won't be 45 degrees but 135 degrees. Of course.

 

[camaro1969]

glue and dowel?

 

[ricebridge]

Two battens, one split into a triangular shape (available at the building market, don't know what it's called) and a regular one are glued together at a 45-degree angle. If you attach it to the inside of the MDF, you're all set.

Sure 17! That's exactly how you do it, now I understand what you mean (slow morning...) It should definitely work with something like this:
https://www.byggmax.se/virke/reglar/50x50-trekantsregel-p08191050
Thanks for the tip!

 

[Malinto]

Hi, Ricebridge! We have the exact same problem now when we're going to build our corner pantry out of MDF. How did you solve the problem?

 

[ricebridge]

Hello, Ricebridge! We have exactly the same problem now that we're building our pantry corner of MDF. How did you solve the problem?

Hey there!
Used a triangular brace between vertical 45x45 studs:

(Here is on the inside behind the door, where I haven't bothered to fine-tune. There should have been a strip along the stud on the right but oh well.)
Here maybe it shows a little better:

 

[Malinto]

Thank you, dear, for the help! Now we know.