Not having the right tools is such a pain.
The modification I’m planning to do requires cutting 72 round 35mm holes into the white plastic foil that forms the Ikea SAMTID’s “head”. I tried to do that with a scalpel, but failed miserably. Getting holes in there is not a problem, but getting them to be perfectly round and have the right size… No way.
Quite some time ago I ordered an affordable hollow punch set on Amazon. Unfortunately the 35mm tools is not quite as sharp as I expected it to be and the plastic foil is terribly tough. So using just a hammer and the hollow punch doesn’t work at all. You can buy some sort of hollow punches used to cut 35mm holes into kitchen sinks, but these are made for sheet metal and I have my doubts if they work for flexible/elastic plastic.
So I came up with this contraption:
It uses 1x M12 bolt, 2x M12 nuts and 2x suitable brass washers to force the hollow punch into the plastic. The principle is sound, but the wood is too soft, the tool is too dull and the plastic foil is too elastic and too tough. Epic failure :-(
I used my mini mill to cut a 15x15mm hole into the wood. The bit is quite short, so I had to flip the wood over and do a 2nd run from the other side.
I tested every available speed from 5krpm to 20krpm. All speeds worked, but at 20krpm the machine became unbearably noisy, so I just settled for 5krpm and it worked just fine. It’s only wood after all.
Here are the not so optimal results. As you can see the hollow punch didn’t make it through the white plastic foil.
The rough edges are the results of me trying to cut “perfect circles” into this tough plastic by hand. Even using a real surgical scalpel with a fresh blade didn’t help. I need something much much better. Something like a compass with a scalpel blade instead of the pencil tip. Punch it into the foil and just turn and cut. That would be ideal.
Here you can see the wood giving in. It is too soft.
Where do I get an affordable circle cutting compass that can handle this type of plastic foil ?
to be continued…
→ Update 1: 20.08.2009:
I’ve found something:
It doesn’t come cheap (about 70€ including 10 spare unidirectional knives, the cutter alone only comes with 1 bidirectional knife), but I consider this a ‘once in a life time’ purchase. Let’s hope this will cut through the plastic foil like a hot knife through butter. The only problem I have is the holes I’ve already cut by hand as there is no center point to hold the cutter anymore. Maybe I can use the piece of wood I scrounged at the local “OBI” yesterday for that.
This ‘circle cutter’ is made by.
→ Update 2: 04.09.2009: EPIC FAILURE 2.0
The new 70€ circle cutter cuts well, is made of metal, has a variable steel centering pin, but the forces during cutting the plastic foil are so big, that the centering pin itself starts to cut into the plastic. So you end up with perfectly cut ‘wanna be’ circles or egg shaped things ;-(
I had to revert to my hole-punch-bolt contraption to cover up an especially nasty failed cut. Using that to pre-weaken the plastic foil and doing the actual cut with a carpet knife works ok, but takes about 10 minutes per hole and makes my hands hurt. There’s a total of 72 holes to go, so it would take ages and drive me nuts. An old friend suggested I use a big drill press with a 35mm drill, but I still have my doubts it would deliver proper clean edges. The perfect thing would be a mechanical or even better a hydraulic press. Then I could just use the hole punch die and a piece of wood and punch the hell out of that damn plastic foil. A lot faster too. “Punch, lift and slide…” So far I’ve only managed to cut about 9 holes.
This one seems to be sold world wide:
2 scales, one for small and the other one for big circles:
The last hole is a bit off, to cover up the mess caused by the center-pin moving around in the plastic:
This is what it should look like when all is done. The green is fake ;-)
If I keep wasting money on tools like that for any longer, I will run out of cash. Well equipped with tools I can’t use, but still out of cash.
To be continued…