Lens Mounting and a Holy Bed

My Lightobject 18mm laser head for K40 did not come with a mounting plate.

However it does come with an air assist nozzle.
The K40 laser head parts are as shown below.

Fortunately Bart dimensioned the mounting plate on his drawing for the lens/mirror assembly (b28018).

I drew this out on a piece of paper and then attached it to a suitable piece of aluminium plate.

This piece was actually cut from the chassis of an old piece of video equipment, so effectively free.

I used a hacksaw to cut off the excess and centre punch where the holes should go.

Filed the edges to the lines and drilled out the various holes.

Then used some hand files to open out the slots.

Finally removed the paper template and de-burred the finished piece.

Actually the 10mm hole was not large enough for my laser head, so this needed opening up to about 13mm, which I did with a conical drill.

Here it is with the laser head attached and a mirror installed in the head.

The slots were dimensioned as 5mm wide, however the screws and lock washers are only just wider than this, so I installed some small penny washers to spread the tightening forces.

Here you can see I have also attached the compressed air hose to the air assist nozzle.

As can be seen from the laser head name above, it is intended for an 18mm lens, now the cheapest 18mm lens from Lightobject is $19.00 for a F50.8mm lens, the higher quality ones are $42.00.

I discovered that on Ebay at least 20mm lenses could be purchased for quite a bit less than 18mm ones.

Now the lens holder has a step at the bottom to hold the 18mm lens, however the holder itself has an inner diameter of 20mm, so it was simply a matter of chucking the holder in the lathe and machining the step off to make a 20mm holder.

I purchased two 20mm lenses with free shipping from Ebay for £16.74, back in 2016, we will see how long they last.

Some time back I purchased an egg crate grille for a dropped ceiling light fitting.

I removed the outer frame and cut the grille to size for use in the Z axis.

I also purchased a piece of stainless steel expanded mesh which I also cut to size with some tin snips.

Here is the expanded mesh in place on the Z axis.

Here is the egg crate grille sat on top to the mesh.

I will need to print some additional tabs to hold up the sides and corners of the mesh to stop it sagging.

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