Quickly Adjusting Laser Cut Box Finger Jonits

Could probably be posted under a few categories, but I am trying to do this on Laser cutter so decided to place it here.


I downloaded the flex/living hinge box from Thingiverse that everyone generally seems to start with. The finger joints in the design are specifically for 3mm thick sheet/stock. I have several pieces of leftover whatever of varying thicknesses.

Q: is there an easy why within the design software (AI, Inkscape, RDWorks) to quickly adjust the depth of the finger joints uip or down by 1, 2, 3 mm? As in select line segments of interest and click a tool or button? Or do I have to go dink with each line and adjust individually?

Are you sure you’re not talking about the width of the finger (or box) joints? the object of a finger joint is to cut all the way thru. So if it is the same color (power) as the living hinge which is also cut thru there is nothing to do.
If it is the width for a tight fit, you need to take the width of the beam into account - which for mine is 0.002" on each side of the joint.

Thanks…I will need to keep kerf in mind, in this case for the Thunder.

Mostly what I am asking is if there is a way to easily/quickly adapt a design for a finger joint for stock of one width to work with a stock of different width. It’s the depth of the finger joints that need to be adjusted to fit new width so that they are flush. I just would rather not have to tweak 3 different lengths or placement per ‘finger’ one-by-one if there is an easier way.

I don’t know of one without a fully parametric model. 3mm material is extremely common, however. 3mm/0.125" (both nominal, btw) is a good material for boxes and such. Its what I cut board game inserts out of.

Plugins for InkScape are written in Python.

I have a Tabbed Box Maker plug-in for InkScape in my folder on the Members drive. It is fairly parametric (settings for plywood thickness, number of fingers, layout pref, etc.). Perhaps you could draw some inspiration from that on how to design something similar.

www.Makercse.com does a great job for finger joints. It exports to an Inkscape file, which you can then edit. For example, I add a cut line for the lids.

Makercase let’s you use exact dimensions for material thickness and laser beam width. It might be easier to start with this file, then add a living hinge.

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The Tabbed Box Maker plugin for Inkscape does this from a pull down menu. I modded it to support printing open-topped boxes as well. (Yay for Open Source!)

Unfortunately, with the many PC updates, the plugins are not currently installed (which is a shame) and I don’t have permissions to do so. As a result, I just use it at home or on my laptop and sneakernet the files to the laser.

@HankCowdog
I heard the plugins were out of date, ie, not working well with the newest updates to Inkscape. Is this true? If not, we can request the machines be updated.

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I have an 092 version (? Not a computer).

The earlier version broke with a recent release due to a deprecated routine being dropped.

I fixed it.

Code is one member drive. I’ll be at DMS today if someone wants to work with me on getting installed there or on one’s personal laptop. Let me know.

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Awesome. Thanks @HankCowdog. I’ll be there today, mostly in the interactive room for our Silk Screening event.

Thanks guys. Good links/hints. They won’t quite solve my problem, which is (admittedly) mostly one of both ignorance and laziness. The design I was hoping to work with to expedite the process is pre-existing (i.e. downloaded) and has a live hinge as well as a semi-circular profile along one end/edge.

But at beginning I was hoping to find the general solution to the problem of how to scale an AI (or DFX or whatever) design in a single direction, e.g. as to height only, length only, width only. I fear @MathewBusby is right regarding the lack of parametricoscoptronominess (there, I can use big words, too!) of the file in question, but that may just be because I fear him in general, as he is truly fearsome.

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