I am playing /experimenting with a small mitre box. I ran into two issues and am wondering, if you do mitre folding, how you deal with it.
How do you hold your stock? It seems that the only way to get an accurate depth of cut is by using tape to attach the stock to the spoil board but I am wondering if there is another way.
How do you keep the pieces attached to each other as you get towards the end of the cut? I have tabs around the outside but you can’t have tabs in the v cuts and the ‘hinges’ at the bottom of the v is only 0.3 mm so the material is too thin to hold things stable.
So I guess the individual pieces of the box stay put as everything is glued down.
How much of a hinge do you leave or do you cut all the way through and then re-connect everything with tape?
The reason I was trying to go without gluing things down is because one half of the box is double sided to form the overlap between bottom and top section.
@Jens I’m interested to see some of your results. Curious to see what happens at the hinge when the grain is parallel to it. I’d probably tape the back side of the hinge before bending to give some support to the fibres.
From what I see so far, if the hinge is thin enough, it will just bend. Taping the hinge improves the odds. I am also thinking that maybe a tad of moisture on the hinge might help although I have not tested that theory yet.
The above is for plywood. MDF is of course a different thing altogether and probably needs to be cut straight through.
Yes and yes re the vac table.. I don’t have enough air flow / vacuum for smallish items when using a flow-through (MDF interface between table and work piece). Once I get to more than 2 or 3 sqft of stock, it works. There is a reason why commercial shops spend the money for powerful blowers.
I have not tried the method that uses a rubber seal (aka Airweights). method with a non air-permeable interface layer.
The vac table is removable and sits on top of my regular spoil board when in use but it has been removed for now.
@gwilki, a question just occurred to me …. you have these 5 or 6 pieces of box components connected with maybe 0.2-0.4 mm thin slivers of material. With using the blue tape and CA glue, can you actually remove the project in one piece? Will the pieces stay connected?
I use double sided tape for all my ‘glue down’ projects and I seriously doubt that I can get the box pieces off the spoil board in one piece. The alternative is to realize that the ‘hinge concept’ isn’t practical, remove the individual box pieces one at a time and re-connect them with tape afterwards.
Often, I cut through the material - just. That way I don’t lose much of the grain.
That said, I have done it leaving the pieces attached to each other. I leave the two pieces of blue tape stuck together and carefully remove the project from the spoilboard. The two thicknesses of tape help to support the thin material. Then, I heat the tape with a heat gun and peel both thicknesses off the material. Did I mention patience? This has worked for me as often as not. As you have already mentioned, Jens, this is very species-dependant, but it is possible.
It’s official …. Mitre Folding sucks the big one !!!
I surfaced my spoil board. I placed another spoil board with no dog holes or cut-outs for clamping and surfaced that. I decided to do this particular item as a single sided job (it was supposed to be two sided). There are two tool changes and they were both zeroed with the auto touch probe for accuracy.
There are 5 panels - a bottom and 4 sides. One of the sides separated but the other 3 stayed connected.
I carefully cut off any excess material and placed tape on the back side to hold everything together. I then glued up the joints and carefully folded everything up. Getting the edge joints right was very much like herding cats. I get one corner just right and another corner goes out of alignment. A 3D printed square might come in handy (place it over top on the outside of the box and use clamps to hold the sides to the square).
After the glue is set, I will see what the corners look like but they will require burnishing for sure.
The resulting box is ok for internal use but I would not give it to a stranger. Very disappointing since I had expected perfection with it being CNC cut.
In regard to the second side of the job - that would have formed an overlapping joint between the top and the bottom of the box. I will be cutting that joint on the router table when everything is cured.
Oh, on top of the joint issues, the double sided tape used to hold everything on the spoil board pulled some of the hair thin veneer off the plywood. Not critical but very annoying.
I suspect that a vacuum table would have helped but it still would require perfection in the glue-up to be of show-off quality.
Not recommended unless you are a seasoned wood worker and done it manually before!!!
