OpenMaking.is

We know that for fixing-less, glue-less joints, material thickness is absolutely key to the function of the design. So how do you figure out what material thickness you have and what do you do once you have it.

To measure your material correctly is quite easy, but it needs to be done very carefully. A good quality set of electronic digital calipers are definitely worth investing in. The best way to get a good measurement is along the edge of the x-axis, in three equally spread intervals, around 1m apart, preferably at each end and the middle. Start with the caliper in closed position set to 0.0mm, open them up and lock them as far onto the edge of the sheet as possible, roughly 30mm. Using your thumb on top and index finger underneath, clamp the pincers as tight as they will go, sandwiching them between the edge of the board. To make sure they are locked and accurate, with your other hand, check that there is no wobble or movement ‘play’. Take the reading to the nearest 0.1. Remove the caliper and repeat the process again, always starting with the caliper closed at 0.0.

Once you have three measurements you can work out the average. Generally they should be within a 0.1-0.3 of a millimetre in variation. If there is a larger variation or you are unsure, the general rule is to go for the smallest measurement as the assumption is there will be other areas of the board at this thickness and historically the edge is slightly thicker anyway.

Measuring Tape

You have your material thickness, so now what. Ideally you would adjust your design files to match the exact material thickness you have, this ensures the joints will be as good as possible but is very time consuming and not exactly repeatable. Other times you might be lucky and the design is less reliant on the joint fit and can absorb some thickness variation. Changing the file for thickness is not conducive to repeatable projects, so you need another way. Enter parametric modelling (the automatic adjustment of the parameters of a design based on a variable input), computer programs have been developed allowing the scaling of a design file automatically based on the input of a material thickness.

Opendesk has embraced this form of modelling as a necessity for repeatable, predictable manufacturing of CNC furniture. We can provide you with the right files for your material instantly. This means that the process of making opendesk pieces is hopefully smoother and hassle free. Most products rely on tight fittings in order to keep them together and solid. Provided the initial measurement is correct we know through experience that our furniture will fit snuggly using our parametric files.