Glueing MDF box with finger joints

Hi,

I glued a box that has finger joints with wood glue and it unfortunately fell apart.
Any tips or tricks I can use from the community here ?

MDF wood 1/8 inches…

Put thin layer and let dry although it is a pain because I have to apply to each finger individually.
Is there a video or something of the amount of glue that should be used and if anything special has to be done to the wood for the glue to stick (and hold weight in the box)… should it be sanded first?
Thanks

1 Like

Wood glue is stronger than wood but MDF is just sawdust compressed into sheets with its own “glue” holding it together.

You probably need to clean up the joints before applying wood glue. Many people use hand sanitizer gel and a soft brush - like a cheap toothbrush - to remove the burned material.

1 Like

Sanding definitely helps with adhesion, but what works best is clamping it firmly for about 15 minutes or so. If it’s allowed to dry in place, with a little sanding, it will become stronger than the wood.

2 Likes

Thanks for the quick answer, however the parts I am putting glue on are not the sides that I cut right… they are right next to it, should I still clean up because residue might be there on the other side ?

Ok thanks will try both sanding and clamping… just need to go and try to find a 18 inches clamp…

1 Like

There is an alternative to gluing called kerf adjusting. Basically, you just tweak the size of the tabs by a hair so that it becomes a tighter fit. If you want to try that out, it eliminates the need for clamping, but it takes a while to get comfortable with it. Some folks prefer a light sanding to rough up the finish (if there is one) and the glue.

3 Likes

There is always this though it sounds like you might want a car inner tube to cut rubber bands for it.

As for gluing; if you fit the two edges together you have a ziz-zag line that is the cut and that is also all the faces that will be glued to the edges and bend that 30 degrees or so and you expose all those edges as well. A very light bead of glue down the center of that gutter and you have just put the glue on every face to be glued. A bit of light wiggling and it will be on every needed face. I keep a wet cloth and some q-tips to wipe away any extra.

Every time you make a box with fingers, you also make a bit of scrap with fingers that you can glue together to make some angle with fingers and experiment making those first and you can use those to hold the glued corners as well.

5 Likes

This is how I glue finger joints for boxes. I saw it a while ago in a YouTube video and thought it was brilliant!

1 Like

I like piecemeal better, and I’m not sure about 18" clamps but the small finger ones work just fine for me… with a jig of course.

corner%20jig

Yes it looks weird, yes its a work in progress, and most importantly yes it works :stuck_out_tongue_winking_eye:

2 Likes

q.v.,

5 Likes

How do you continue in order to complete a box?

Once two sides are glued to one another 3rd falls right in add glue as I go, clamps if overly large 6" length. With the wood glue I use it doesn’t take very long to set 3 minutes is long enough to add the 3rd. With 3 pieces together little need for clamps beyond that unless there is warpage, and then its the outer jig and lots of rubber bands. I have one I’m putting together tomorrow. I’ll take pics as I go.

The important thing to remember about the jigs is they are only there to hold the piece in place til the glue can take over. An extra hand if you will.

Your’s looks much better than mine… :upside_down_face:
Thank you for the link :grinning:

Wish I could like more than once :upside_down_face:

Mine I designed @ 3am after getting off work after looking and NOT finding (at 3am not surprisingly) a design I could work with.

3 Likes

Thank you for linking to this, it’s perfect for the gluing job I have been procrastinating on…

4 Likes

This topic was automatically closed 32 days after the last reply. New replies are no longer allowed.