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Hello all,
I forgot to take off the top layer of the melamine where applicable to create the counter sinks. Will this create problems with assembly or functionality or is it just an aesthetic choice? Should I unscrew the screws and create counter sinks? Also, what is the best way to create the counter sink holes (razor blade?)?

The counter sink holes help you level the head of the screw without deforming or potentially deforming the melamine.

In general, you should remove them. In some cases, it won't matter - but you'll find out along the way that you should - so it's best now to take them out.

Hope you aren't too far.

The best way? A countersink bit, of course. I used a cross-hole countersink cutter. See http://en.wikipedia.org/wiki/Countersink for an example.

- dan

you should remove the layer of melamine, else the screws will not countersink correctly.
they can be easily removed by "popping" the melamine disk out with a small flat screw driver or pointed scribe tool. just stick tool in just below melamine surface and pry it up. no need to use a countersink tool, the soft wood core crushes down making its own countersink. I think this actually makes a nicer countersink than a countersink tool. countersink tools usually make a ragged edge hole because the melamine surface is so hard and brittle.
You might even be able to pop the layer out with a exacto knife without tacking screw out completely?

A fluted countersink bit will likely chatter and leave a ragged edge. The cross-hole cutter I used gave me a clean countersink without chipping the melamine, without fail.

- dan

dbarrans wrote:A fluted countersink bit will likely chatter and leave a ragged edge. The cross-hole cutter I used gave me a clean countersink without chipping the melamine, without fail.

- dan

I did not know that, thanks for the tip. I also have that type of countersink bit, I will use it next time instead of the straight fluted one.

The cross-hole countersink is used for aircraft work for just that reason. Because of the geometry of the hole, it actually slices material away as opposed to scraping it like straight flute countersinks do.

You can't beat a good countersink in a drill press - I actually wouldn't recommend using a countersink unless you've got a drill press as you can do some serious damage if you're not very, very good at countersinking with a hand-held drill motor.

g.

I did all the countersinking on my kit with a variable speed cordless drill. Had no difficulties with it.

- dan

That just means that you were very, very good at it.

g.

Does anyone know where the cross-hole countersink cutter can be purchased?

I started out using an Exacto blade and peeling up the layer of melamine as suggested, which was a pain, when more than 3/4's of the way through the build I discovered the absolute EASIEST way to do the "countersinking", and you can do it as you go along with the intended screw in hand!

So you have the flathead screw in your hand that you want to install in a laser etched, countersink marked hole:

--Just take that screw, insert just the tip (yes, I just said that!) into the hole just as deep as you want your countersinking to be
--now, maintaining that depth, you simply tilt the screw so that the tip leverages against the side walls of the hole, and A PERFECT ROUND STACK of melamine will pop CLEANLY out!

Why does this work so well? Underneath the top layer, the internal particle board seems to be a densely packed, layered material itself.

When the laser etched hole is created, the laser apparently cuts past not only the outer plastic layer, but also several layers deep into the underlying material. So what is sitting there isn't just one surface ring, but a stack of them. Prying with the screw in the above fashion simply prys out a stack of them. How much of that stack is up to how deep you put the screw in. Just the tip! LOL

Happy building!

Rob