Experiments in making marudai and tweaking tama

Other Crafts Braiding and Knots
1

That little foam kumihimo disc is nice but it hurts my wrist to use for more than 5 minutes. Proper kumihimo equipment is a little pricey for something I might not wind up using very much. Enter my new 3D printer…

I figured I could put something together myself much more cheaply, and if it worked out I could share the files so anyone else could print the parts too. I’ve designed all of the parts, but have only had time to test the tama. It’s promising so far; 43 cents (USD) of plastic and 19 pennies for weight gives me a 70g tama. It’s a bit hard to see in the picture, but the one on the right is filled with pennies.

My plan is to print the tama, kagami (disc), and base, and buy wooden dowels for the legs. The kagami and base are going to take practically all day to print (each!), so it’ll be a little while before I know for sure that they’ll work. Once done, the tama and kagami are going to need a fair amount of sanding to be smooth enough to not snag the threads, and I’ll have to glue the caps on the tama. So, it’s certainly more work, but it’s fun and much less frustrating than trying to do the woodwork myself!

IMG_20190725_113259_405.jpg

2

@HeatherAthebyne , I am new to kumihimo so don’t know very much, but following your progress on this will be interesting! Thank you for sharing.

3

Hooray! The printed base turned out great. This was my longest print yet (15.5 hours) and I’m pleased that it went well.

I left a little bit too much space for the wooden dowels, so they don’t fit snugly, but that’s easy enough to shim. Dowels can vary so much in diameter, anyway.

Next up will be the kagami, at a more reasonable 8 hours.

IMG_20190727_061649_663.jpg

4

3D printer! I am soooo jealous.

5

It’s so much fun! And so much more tuning and tweaking than I expected going in :slight_smile:

6

Fascinating to watch your progress
what info are your using for the design of the mirror

7

I’m using the diagram from https://amksoc.org/wp-content/uploads/2018/06/Marudai-Measured-Drawing.pdf .

8

I’m only planning fine thread work right now, but knowing myself, I could dive into other things. What did you have in mind?

Oh, I’d also like to thank you for the linked page and blog post. Your blog post was my first introduction to the importance of the well :slight_smile:

9

I am glad to hear you found that article helpful. As you likely know - I have been braiding, “not just Japanese/Kumihimo” for a rather long time -
So long ago in fact, that more than once I accepted various forms so censure for using unusual threads and OMG - EEEK Beads.

With the advent of the disk and those who embraced it for simplest braids, often with beads for jewelry and accessories -

Michael’s measurements work quite well and (forgive the pun) Mirror the traditional style

When you move to novelty threads and beads and other inclusions, a bit of different thinking may be needed.

The first evidence of that is when the BeadSmith changed their Disc design to a 35mm from 25mm. Not quite the 38mm Kagama No Ana (center opening) Michael specifies,

Which leads to a LOT of Rube Goldberg experiements and some of a more refined nature with Tim Hale of http://www.fiberartistsupply.com

As you already know, the purpose of the “dip” is to allow threads to be suspended, thus “evening” tension.
the problem is that many novelty and beaded threads they do not suspend freely with a shallow bowl.

After making Michael (and others) nuts, several agreed that yes, the traditional desire could be modified to give more air, BUT as much as possible the same degree of angle should be maintained.

Some - who did not braid with novelty threads except in their nightmares, suggested more counterweight - and that had been my first idea, but as you know that just elongates the stitches and leads to loose braids - not usually what you want.

my solution was function over form. Instead of a “graceful curve” I asked for a thicker mirror (we ended up with two layers) so that the “drop” was straight sided like a round cake pan

I found that a 1;5 inch drop from out rim to Kagami no ana, worked well me and was reasonably close to the traditional
what I Liked, was a 2 inch drop The deeper drop does not seem to affect the finished braid.

I envy you the 3d printer, it is so much cooler than cheap cake push bans with their center cut out with grommets around the cut and round wooden frames from a craft store for the outer rim.

In keeping with the push pan - you could probably make inserts with various sized kagama no ana to be used for different projects.

Another day maybe we can chat about your tama design choices. I am curious

10

Oh, and I will have to find the article for you - but the total height (top of kagama to floor) is also something you may want to customize to fit you.
but right now I need more coffee to think about something else.

11

Hmm, I should mention that I have to scale down the mirror from Michael’s dimensions to fit on my printer at all, and my current design is only 120mm in diameter. It’s meant as a proof of concept and to minimize the space dedicated to fiber equipment that I may or may not use extensively :wink: I went with a 25mm thick mirror and 25mm kagami no ana, but preserved the other proportions given in Michael’s design – so the well is proportionally as wide and as deep as specified, given the 120mm/25mm dimensions. I do expect to only do fine threads and eight tama on this iteration.

Speaking of tama, I can say that my design criteria were only “close to Tim Hale’s tama, with thick enough walls to accept a load of pennies and not snap in half”. Pennies are my go-to for cheap weights at gram scale. It was a happy accident that I hit 70g on the nose with this design and one fewer penny than the tama has space for…

12

I got the mirror printed today in a nice bronze shade. It’ll be a few days before I can get it all put together; I have to pick up a couple of dowels and wait for the epoxy coating to arrive for the printed parts. I had a notion of sanding the mirror and tama smooth, but the present condition of my shoulder makes that a bad choice. Epoxy will be less time-consuming, anyway, and I still have five tama to print.

IMG_20190729_172334_256.jpg

IMG_20190729_172358_590.jpg

13

I would not worry too much about that - it may mean some braids will be a bit crowded, but you should be able to handle quite a few -

14

3D printing is fun. Really, it is…

I’ve been having some trouble with parts staying adhered to the print bed, so I’m kind of stuck on the last two tama until I can figure it out. I have plenty of remediation options, but I’d rather figure out why it’s started happening all of a sudden. Humidity? Some residue on the bed? Phase of the moon? It can be hard to tell. It’s going to be stormy on and off through Monday, and the printer isn’t on a battery backup, so I’ll probably hold off on further troubleshooting until afterward.

Not that I don’t have plenty of other things to do – I got the dowels, so I can start thinking about height, and I received the smoothing epoxy. If I can wrap up the other things occupying most of the space in the garage/my workshop, I’ll be able to set up a workbench to smooth a few test parts.

IMG_20190731_143813_681.jpg

15

Whew! After cleaning the print bed more thoroughly and adjusting the print settings a little bit more, I have the last two tama and caps printed. Next up is to make a space in the garage to apply the coating; lots of new shelving is all well and good, but putting the piles of stuff on the shelves is also important :wink: