This weekend I went to a LEGO exhibition with my daughter, and I gained a little nugget of information about how they fuse some of their parts together, which I thought I'd share, in case somebody finds it useful. They use sound waves, more specifically at 20kHz, they didn't mention a specific amplitude, but the machine operators are required to wear hearing protection, so I guess it is pretty high. The board said that at 20kHz the friction between the pieces would be sufficient to cause the blocks to fuse. The specific example was a LEGO window, where they used sound waves to fuse the transparent plastic with the frame. https://reprap.org/forum/read.php?1,36904,36904#msg-36904 Sun, 16 Aug 2026 21:12:24 -0400 Phorum 5.2.23 https://reprap.org/forum/read.php?1,36904,36974#msg-36974 https://reprap.org/forum/read.php?1,36904,36974#msg-36974 johnrpm General Mon, 22 Feb 2010 15:58:25 -0500 https://reprap.org/forum/read.php?1,36904,36935#msg-36935 https://reprap.org/forum/read.php?1,36904,36935#msg-36935
I've been wondering if this can be used as an epoxy for joining the thermal barrier to the extruder block.]]> mccoyn General Mon, 22 Feb 2010 11:23:19 -0500 https://reprap.org/forum/read.php?1,36904,36907#msg-36907 https://reprap.org/forum/read.php?1,36904,36907#msg-36907 -------------------------------------------------------
> This weekend I went to a LEGO exhibition with my
> daughter, and I gained a little nugget of
> information about how they fuse some of their
> parts together, which I thought I'd share, in case
> somebody finds it useful.
>
> They use sound waves, more specifically at 20kHz,
> they didn't mention a specific amplitude, but the
> machine operators are required to wear hearing
> protection, so I guess it is pretty high.
>
> The board said that at 20kHz the friction between
> the pieces would be sufficient to cause the blocks
> to fuse. The specific example was a LEGO window,
> where they used sound waves to fuse the
> transparent plastic with the frame.

Nice! Thank you ;-) -- This is interesting, I am sure we can use this info later.]]> casainho General Mon, 22 Feb 2010 05:53:41 -0500 https://reprap.org/forum/read.php?1,36904,36906#msg-36906 https://reprap.org/forum/read.php?1,36904,36906#msg-36906 VDX General Mon, 22 Feb 2010 05:12:33 -0500 https://reprap.org/forum/read.php?1,36904,36904#msg-36904 https://reprap.org/forum/read.php?1,36904,36904#msg-36904
They use sound waves, more specifically at 20kHz, they didn't mention a specific amplitude, but the machine operators are required to wear hearing protection, so I guess it is pretty high.

The board said that at 20kHz the friction between the pieces would be sufficient to cause the blocks to fuse. The specific example was a LEGO window, where they used sound waves to fuse the transparent plastic with the frame.]]> anton General Mon, 22 Feb 2010 04:58:50 -0500