J-G
Established Member
Strange how ideas evolve! - For the two boxes I've made recently I used the same Catch (a close up photo is on the early December post) but I had to add a [Pop Up] pin so that when the catch was released the box lid did 'pop up'. Whilst the arrangement works, it occured to me that I could combine the two elements into one and the 'action would be much more efficient. The separate element relied upon a 2mm Ø hole drilled in wood into which a spring & a brass pin were held in by a 4mm Ø Ebony plug CA Glued in.
Today I made a prototype of the combined catch :
It's difficult to appreciate the scale but the main body is 12x12x5mm, the 'Pop-Up' pin is 1.5mm Ø and the spring 3mm Ø.
The images below show the components exploded - I've added a 5p coin to give a better sense of scale but that only appears in the second.
The Pop-up spring is 1.5mm Ø and sits in a 1.6mm Ø hole drilled 2mm into the M3 x 5mm Grub Screw.
I don't yet have a box to make but this will most likely be fitted to the next one I do.
[EDIT]
Overnight I thought on the potential problem that the actuating rod might 'wander' - my normal rod is 1mm Ø and in previous versions of this catch I was able to drill a 1.2mm hole in one side and a 3mm hole in the other for the spring.
With the combined unit I had to drill the 3mm Ø spring dimple from the actuating side, which means that there is a 3mm hole for the 1mm rod to wander about in. You can see it quite easily in the first image.
This morning I machined a 3mmØ x 1.5mm 'plug' with a 1.2mmØ hole which I glued (CA) into the 3mm hole. After 5 minutes I was able to re-machine and re-polish the dovetailed side.
The 'plug' becomes visible purely due to the various stresses incurred.
This time I did remember to add the 5p coin for scale comparison
Today I made a prototype of the combined catch :
It's difficult to appreciate the scale but the main body is 12x12x5mm, the 'Pop-Up' pin is 1.5mm Ø and the spring 3mm Ø.
The images below show the components exploded - I've added a 5p coin to give a better sense of scale but that only appears in the second.
The Pop-up spring is 1.5mm Ø and sits in a 1.6mm Ø hole drilled 2mm into the M3 x 5mm Grub Screw.
I don't yet have a box to make but this will most likely be fitted to the next one I do.
[EDIT]
Overnight I thought on the potential problem that the actuating rod might 'wander' - my normal rod is 1mm Ø and in previous versions of this catch I was able to drill a 1.2mm hole in one side and a 3mm hole in the other for the spring.
With the combined unit I had to drill the 3mm Ø spring dimple from the actuating side, which means that there is a 3mm hole for the 1mm rod to wander about in. You can see it quite easily in the first image.
This morning I machined a 3mmØ x 1.5mm 'plug' with a 1.2mmØ hole which I glued (CA) into the 3mm hole. After 5 minutes I was able to re-machine and re-polish the dovetailed side.
The 'plug' becomes visible purely due to the various stresses incurred.
This time I did remember to add the 5p coin for scale comparison
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