My first compass was a Staedtler, and I’ll be honest with you, I had no idea what a good drafting compass looked like back then.
I just went to an art shop and bought the first one I saw HA! As long as it had two legs, a steel point and a lead point, it was good for me.
No one ever told me what to look for when buying a compass, which are the various parts that the compass is composed nor which are the materials the compass should be made of.
That was until I had an interesting conversation with Alan Adams, who generously shared his knowledge with me.
Here I am now sharing all these valuable info with you all.
In this blog, I’m talking about the various parts of a typical 6-inch compass, which is the most common one.
1. HEAD JOINT
A head joint is what keeps the legs together. If the head joint is loose, the legs will move thus causing accuracy issues in your drawing. Pay attention to this part and make sure the head joint is tight and firm.
2. THUMB WHEEL
The best compass has a wheel between the legs. That wheel is what makes your compass adjustable but stable. Once you set the compass opening, the legs are not going to move because they are secured with a little tie rod. This kind of compass also has two kind-of buttons on the legs that you can press to open or close the legs instantly without rotating the central wheel
3. FOLDABLE LEGS
Another essential thing to look for is foldable legs. You should always bend the legs of the compass to keep them perpendicular to the paper. Otherwise, the pressure you put on the compass while using it will make the legs open up a little bit more, thus causing accuracy problems.
If you can’t bend the legs of your compass no problem, I got you covered. Search for a compass with an adjustable steel point. Almost every compass has a screw just above the steel point. In most compasses that screw allows you to extend the steel point but in some cases, you can also move the steel point left or right to keep the point vertical to the paper.
4. PEN ADAPTER
A pen adapter for a geometry lover is like Nutella for a food lover. To be able to use your favourite mechanical pencil with your compass instead of the large chunk of lead that comes with it, it’s such a blessing. Try it; you can thank me later.
I know it’s tough to find a compass entirely made of steel because the only manufacturers that still make compasses nowadays (like Staedtler and Ecobra) use plastic but believe me, there is nothing better than a compass made of shiny stainless steel. I’m not saying this just because plastic looks odd but also because, unfortunately, plastic wears out very quickly and that can lead you to inaccuracy.
There are different types of drafting compass and these 5 things may not apply to all of them but you get the point.
If you want to know which compass I use, check my supplies list here
What Makes a Good Drafting Compass?
April 30, 2020
Excuse me if you have mentioned this previously, but all the vintage compasses I see don’t seem to have a pen adapter. Is there a standard size so you can fit a pen adapter to them and can you buy stand alone pen holders?
Hi Vivien. You are right. Some of the vintage compasses (I think Rotring) have the pen adapter incorporated in the compass structure. This means that compass doesn’t have the lead point but it comes with a pen hole. But this is not always the case. In that case buy hard leads for the compass and sharpen them with a lead sharpener.
I am just trying to make sense of what Islamic Geometry and I absolutely like this detailed post on what to look for in a compass; however I would have appreciated if there some pictures to show the part you’re mentioning in each point.