OctoSquare OctoShape?


Here is my mk1 JLF octosquare. I was very happy that from my measurements of the base this fitted tightly on my first attempt. There are some visible manufacturing errors that don’t affect function which I’ve now fixed, I’ll make a prettier one tomorrow.

I would describe the above as C19.5 D20.5 R6.0 (1.05)
= Cardinal 19.5mm, diagonal 20.5mm, fillet radius 6.0mm (ratio D/C)

But now we have to note that if we want a set of numbers that describe the feel of a gate, then we have to take the radius of the follower away from the gate dimensions (a 5mm radius follower in a 5mm corner fillet gives a sharp corner)

And lets talk about throw rather than diameter,

So now I change the above (for my dia 10.6, radius 5.3 follower) to:
C4.45 D4.95 R0.7 (1.11)

Note: the ratio is now realistic, and will range between 1.00 octagon to 1.41 square

Finally we want to translate that from the gate to the handle. And as my gate is 4mm rather than 6mm thick, that will alter things slightly.

I’m going to use the figures: 48mm pivot to ball centre, 26mm pivot to my gate contact.

With a bit of rounding I end up with:

C8.2 D9.1 R1.3 (1.11)

If you keep the ratio at 1.00 and change the radius, then you are moving along a scale from octagon to circle, so maybe octoshape is a more general name to cover all combinations


Oh yes, I think I prefer this shape to the circle for Robotron. I don’t play fighters.


You planning to make these available to the general public?

Maybe you can work out a deal with someone like @armi0024‌ from Paradise Arcade Shop to get these out (and make some money in the process.


This one is slighty squarer. C19.6 D21.2 R6.0 >>> Throw C9.0 D10.6 R0.7 (ratio1.18)

It’s an optical illusion making the cardinal fillet radius look sharper than the diagonal fillet radius, both are 6.0mm.

Yes, I will be setting up an arcade parts shop (catering to Europe mostly). But as these are <5mm thick I could send them worlwide for a few dollars.

I should be able to get them into Armi’s shop (or he’ll make something similar).

These have been made to fit my (nice) jlf clone, I don’t have a real jlf to test the fit on. If a few of you want to test the fit for me, and be the first to test the shapes, I will ship worldwide for $4 shipping (up to 3 restrictors) and $3 each restrictor. If they don’t fit nicely, I will rework the locating holes based on what you tell me and send you replacements.

If no-one takes me up on the offer I’ll buy a JLF and check the fit myself :slight_smile:

Also I need the measurements of the JLF square and octo gates for a baseline. I’ll do some searching. Hopefully my clone restrictors are close copies of the JLf and the sizing is comparable.


My calculated throws were a bit on the low side, due to my estimate of where the pivot is. I thought it was level with the top of the base, but I now think it’s near the top of the pivot piece 2 or 3mm lower (seems sensible, pivot a full hemisphere). Changing my lever arms to 50mm and 24mm I get new throws which are closer to what I can measure.

Also I forgot to magnify the efective corner fillet for proto_02. So these are the corrected theoretical specs

proto_01: C19.5 D20.5 R6.0 >>> Throw C9.3 D10.3 R1.5 (ratio1.11)
proto_02: C19.6 D21.2 R6.0 >>> Throw C9.4 D11.0 R1.5 (ratio1.18)


I came up with a similar design. Haven’t had time to manufacture yet, for a number of reasons.