Cassette Tape Splice Block

A simple splice block based off ¼" tape splicing blocks but for the width of cassette tape. I use it with a thin razor (it actually is the blade from a PTFE tube cutter) but I think an Xacto knife will work as well.

Just like with a ¼" block, you lay down the tape magnetic side down, overlapping each end across the slice point. You need to hold the tape down with something. I recommend a Post-It note as these are just sticky enough to work, but not so much they make it hard to remove.

I usually put a finger on the side with the top overlapping tape and then use the blade through the slice channel right over the tape, initially pressing down with moderate pressure and then pulling it down through the channel. The extra bit from the top tape will come off and can be discarded. Now grab some splice tape (or Scotch tape if you don't have splicing tape), trim it if need be and place it over the splice. The tape will want to curl up so you may need to hold it down and sort of roll the splice tape across.

Remove the tape from the block. You should see the extra bit of tape cut from the bottom splice leftover. If not, make sure it didn't somehow get taped to your splice.

And that should be it!

Notably, cassette tape I find is much harder to work with and this did take some practice. The tape is much thinner and narrower than ¼" tape and it curls upwards when placing record side down. Even so I find it's much MUCH better than trying to splice without a block.

Printing

This is not a complicated part. I print mine with 3 perimeters, 20% gyroid infill but with at least 6 solid layers on top and bottom, since we're pressing down with a sharp blade. The material doesn't matter as much here I don't think. PETG might be a bit nicer to the tape as I find it's more “slippery” but I printed my blocks in just rando PLA I had lying around.