Renewal of special bicycle parts with 3D printing

Mr. Odagaki, who cooperated with this interview, rides a bicycle as a hobby. The proud machine has a special shape that allows you to lean back and row. However, I recently ran into a problem. Due to the special shape of the replacement for the damaged bicycle part, it was no longer available on the market. Even if we asked for an increase in production, we were at a loss because the probability of obtaining the same product was low because small-lot production was not profitable.

3D printing technology is the solution to these problems. As an example of 3D consulting by 3D Printing Corporation, we will introduce the process of Mr. Odagaki's bicycle parts regeneration.

Background of introduction: Searching for substitutes for special parts

‍The damaged part is the protective plate that covers the relay gear of the chain that connects the pedals and the rear wheel. Since the relay gear protrudes a little to the side when viewed from the top, the taut chain constantly rubs against the protective plate, applying force and eventually breaking it. When it became clear that it would be difficult to re-obtain the relevant parts, Mr. Odagaki first tried to repair them on his own. It seems that he used a commercially available adhesive to reattach the parts, but it broke again in about a month or two, probably because the strength had decreased.

Damaged bicycle parts (chain relay parts)

Next, Mr. Odagaki asks his brother, who owns a metal parts processing factory, if it is possible to create the parts in question. The answer is "difficult". In the existing method of making and creating a mold, it is not possible to start manufacturing unless there is an order of at least dozens of pieces, and even so the cost per unit price will be enormous. Mr. Odagaki was the only one who was in trouble without parts this time, so it's very unrealistic.

When he was in a stalemate, he happened to come across an article in which Mr. Koga, the CTO of our company 3D Printing Corporation, was talking about manufacturing bicycles using 3D printing. Mr. Odagaki, who had been acquainted with Koga and the CEO for some time, thought that it might be possible to manufacture parts using 3D printing technology, and contacted us.

Mr. Odagaki and our employees

Operation method and effect: speed of new parts production and level up of new parts

‍After receiving your request, 3D Printing Corporation's 3D printing solution begins. First of all, I sent the dimensions and photos of the relevant parts by e-mail, and based on that, I made a guess and 3D printed the parts. In response to Mr. Odagaki's request, "I want to make a cool design," the design team put their ingenuity into action. From getting the information to completing the 3D data, it took less than an hour. Your skill shines through. The 3D printer will do the modeling later within a day if you leave it alone.

Elaborate design of prototype parts

When I sent the completed prototype parts to Mr. Odagaki for confirmation, it turned out that they did not work well. Due to the lack of prior information, this can't be helped. From here, we go into consulting. What is the function of the part, and what kind of shape can achieve the purpose? With permission, I also disassembled it to understand the existing parts.

As a result, the parts are relay devices for the chain, and instead of being attached as a simple protective plate with the same shape as the initial shape, the designer team thought that by rotating themselves, smooth drive could be expected. I was. Consulting with limited points and designing improvement proposals can be completed in about an hour.

Now, leave the modeling to the 3D printer, and when the output is completed, it will be a trial run on site.

"It works! It's cool. It's how it should be!"

Mr. Odagaki was most delighted when he saw the real thing. Thanks to the ingenuity of the design team, the parts with ball bearings now run much smoother than before. The material is tough and smooth epoxy resin (EPX82). Rubbing on the chain is also greatly reduced, and this time it seems to last longer.

“When I first bought it, the chain rubbed and made a harsh noise.

Parts renewed not only in design but also in terms of function

Yamaji, the DFAM engineer at 3D Printing Corporation who proposed the improvement this time, commented on the devised points while looking a little embarrassed.

“Because the ball bearing is embedded, there will be a part that sticks out so that it does not come off (see the figure below). It must have taken a long time, but with the Carbon 3D printer that I chose this time, I was able to create something like this while floating in the air.The Carbon DLS™ process is like magic.”

Gray part: part that floats in the air during modeling (drawing to be revised)

With 3D printing, it is possible to regenerate and improve parts that have been discontinued, such as this time. What should be noted is that it can be saved as data, so even if this part is damaged, it can be remodeled any number of times. What's more, you can make it with a 3D printer facility at home or in your neighborhood*. This is a part that cannot be imitated with existing injection molding technology that requires lot numbers for manufacturing.

*If you do not use an industrial grade 3D printer, there may be large variations in quality.

Future prospects

After enjoying the bicycle with the renewed parts for a while, we asked Mr. Odagaki for his impressions.

"The ride is different. I'm impressed. My brother's factory also has a 3D printer, but it's not being used in this way. I'm going to stay. I'm going to make something like a pen holder, and that's it."

In response, 3DPC Yamaji nodded.

“By understanding the role and structure of each part, we can come up with better methods. The ball bearings we are developing are a good example of this. With a 3D printer, even complex shapes that were previously difficult to create can be created.” .

"That's exactly the strength of 3D Printing Corporation. They have engineers who are familiar with machine design and design, and they have their own 3D printers, so everything can be covered by one company. Hints from a little consulting. He found the , and accurately molded the better parts."

Back to blog