Throw away your tape measure!

[Steve Maskery]

Well, maybe not throw it away completely, but certainly use it less!

I'm currently building a wardrobe, three big boxes sitting on a plinth. The carcases are made from oak-flavoured MDF with solid lipping, the base is solid oak. Everything has to fit together, of course. But there are lots of component parts – tops, sides bottoms, doors, long rails, short rails – the list goes on. I can't afford to make mistakes when measuring, and it is all too easy to get 89 and 68 mixed up, or 1010 with 1100, so I don't measure at all. So how do I get everything right?

The answer is to take all the measurements, not off a tape measure, but off a full-sized drawing. Here in the UK we call it a Rod. In the US they call it a Story Stick, but it's the same thing, a length of wood or a board with all the key dimensions marked on it.

This wardrobe is 1.9m wide and 2.1m tall, so I have piece of melamine board 2.4m long and about 250mm wide. All my horizontal dimensions are drawn out on one face. I need my tape measure for that, of course, and a selection of other marking out tools – square, rulers, eraser, pencil gauge, compasses, as well as the original paper drawing,

but when the rod is finished, I won't need to measure anything again.

I mark in my vertical sides, across the width of the board,

then draw in the height (along the board) of the plinth and dividing frame

Then I can draw in the thicknesses of the individual panels and cabinet bottoms, and clean up the extraneous lines.

The result is a full-size drawing of the lower part of the wardrobe assembly. I can see what it's going to look like and I can check that all the measurements are as they should be.

The other side of the melamine has all the vertical dimensions marked on it, from the floor right up to the top. It's useful to mark one end with a Datum mark, like this:

so that I mark from the correct end of the rod. This is particularly important if some of the dimensions are close to the centre - marking off from the wrong end could really spoil my day.

A second board has all the front-to-back dimensions drawn on it.

So once I have these Rods and I have checked that all the dimension are correct, and all the lines are correctly labelled, I can put away my tape measure and ruler. When I need to make a cut, I put the workpiece on top of the rod and mark off directly from the pencil line. It doesn't matter what the dimension is, it is “that much there”. I still have to be careful that I mark from the correct pencil line, of course, and that is particularly important if there are several lines close together, but at least it saves me from mixing up similar numbers, especially if I am using my tape measure upside down.

There are other advantages to using a rod, besides avoiding measuring errors. They can show up potential problems that would never show up on a paper drawing.

For example, when I drew up the smaller rod with the front-to-back dimensions on it, I saw that I had originally drawn up my design with the front of the base plinth flush with the front edges of the carcases. But when I drew in the doors as well, I could see that the front of the plinth was further back than it needed to be. As a wardrobe is relatively shallow, compared with its height, and this is going to be on adjustable feet, I could see full-size where the feet would end up. They are not very far apart and I need as much stability as possible. By bringing the plinth forward to be flush with the doors, rather than the carcases, I could get another 21mm or so of spread. It may not sound much, but every little bit helps and I would never have spotted that if I were working solely from an A4 drawing.

Another advantage is the ability to modify the design as the job progresses, if needs be. For example, when I have made all three cabinets and stand them together, I can check if they really are identical to the rod. If they are, great, but if cumulative cutting tolerances mean that there is a mm or two discrepancy, I can simply modify the rod to reflect reality, before moving on to the next stage.

So why not try making your next project with a rod rather than using your tape measure? You'll soon get the hang of it and it may save you making some very costly mistakes.

 

[doctor Bob]

I like a rod but only for unusual stuff, that would all be done on the panal saw just using the stops. Interesting read though.

 

[transatlantic]

Sounds more awkward to be honest. I'd rather take a tape measure to a board, than a board to a drawing. Although it would certainly make sense for repeat builds.

And visualising is easy with 3d software.

But we all work in different ways!

 

[Adam9453]

Interesting read Steve.
3D design and an automatic cutting list extracted directly from the model, auto updates when you amend the design. Saves a lot of human error, especially when combined with cnc machines but I’m comparing fish with chocolate

 

[Steve Maskery]

Interesting read Steve.
3D design and an automatic cutting list extracted directly from the model, auto updates when you amend the design. Saves a lot of human error, especially when combined with cnc machines but I’m comparing fish with chocolate

LOL!
Yes you are. The question is, Which is Which?

Now then, where did I put my Fanuc?

S

PS I like both fish and chocolate, just not both at the same time...

 

[Chip shop]

While I was taught to use a rod, to be honest, I tend to use CAD for design and build now. DIMS on the drawing of the various components and you're good to go. Cut one component, then 'measure' all similar components off that

I cocked a rod up once and five internal doors basically became firewood. It wasn't a good week, I seem to remember having to eat spaghetti hoops on toast for tea :lol:

 

[Sam R]

Sounds more awkward to be honest. I'd rather take a tape measure to a board, than a board to a drawing. Although it would certainly make sense for repeat builds.

And visualising is easy with 3d software.

But we all work in different ways!

The point is that a tape measure/rule only tells you what the dimension is, not if it is correct. When making, it is simply impractical to keep all the numbers I your head, so you have to keep checking your cut list or perhaps drawing. A rod is a much easier way as it gives a definite reference. Once I've done the rod, the tape sees little action.

As for CAD making visualisation "easy", it's not so simple. Drawings with dims, be it CAD or draftsman drawn may be fine for joiners or simple objects. For furniture where form & proportion - the tricky thing to get right - are critical, it is important to understand that the eye doesn't see an image on a screen or sheet the same as full size 3D object. For any development design I am increasingly convinced of the merits of prototypes that model the dimensions. Car manufacturers went back to clay models in the '90s/'00s for this reason. I also find it quicker to resolve construction details on a full size rod or drawing than tediously modelling in CAD. The caveat for all this is that I'm doing the making in small numbers rather than it being in a mass production setting.

 

[RobinBHM]

Rods are an excellent method to help with setting out.

They also help reduce mistakes due to errors when not marking shoulder lengths -especially important for joinery setout.

Rods are a good aid for for those that struggle to visualise the setting out.

I have a chippie friend that comes into my workshop sometimes to build wardrobes or alcove units.
He always has to build the carcase first because he cant work it out from measurements. He uses a rod.

I slways make the face frame and doors first, but I work everything using calculations.