Safety and the Home Lab

Hello All,
Not to sound like a radio talk show caller but: Long time reader, first time member here at LPF. I am finally getting around to setting up my own home lab rather than continuing to use my friends work lab. Here are my questions for the community at large:
I) What do you recommend using for a beam stop? (Is a graphite block with a 'cup' shape in it enough?)
II) How likely is a 1W 445nm blue laser to heat cinder blocks sufficiently to explode? (As they would when exposed to intense heat)
III) Do you think it is worth building an anodized aluminum 'range'-like structure? (Kind of like at a firing range)
IV) Is there a reason why most hobbyist laser 'cutters' are built with the laser firing into the ground? (My experience with CNC type machines would make the opposite easier to construct personally)

Anywho, thanks everybody! Special shout out to Steve (LSRFAQ) whose long standing position on safety helped me start out right year ago!

1. I recommend a good beam dump if you're working with higher powers.
2. Not very.
3. Like an optical table?
4. Probably for ease of loading materials - plus gravity pulls things away from the optics.

-Trevor

to the Forum...

Don't forget to read the Newcomers section... the FAQs...
the Stickies and the Forum Rules...

I) Yes...

II) Not at all... Get yourself a Fireplace liner Brick.. they can handle
large amounts of heat if your worried..

III) No...

IV) It keeps the dust out of the optics and it has a short way to go
before the beam stops.. It is also difficult to place and align parts to
be cut from the bottom up... IMO

Enjoy the Forum...


Jerry

i remeber reading you can make a beam dump with razor blades the box cutter kind and very thin washers spacing them apart.
I dont know where i heard it but i do remember you can make something like that.

twhite828 said:

1. I recommend a good beam dump if you're working with higher powers.
2. Not very.
3. Like an optical table?
4. Probably for ease of loading materials - plus gravity pulls things away from the optics.

-Trevor

Click to expand...

III) Kind of like an optical table, but with more range to it.

lasersbee said:

to the Forum...

Don't forget to read the Newcomers section... the FAQs...
the Stickies and the Forum Rules...

I) Yes...

II) Not at all... Get yourself a Fireplace liner Brick.. they can handle
large amounts of heat if your worried..

III) No...

IV) It keeps the dust out of the optics and it has a short way to go
before the beam stops.. It is also difficult to place and align parts to
be cut from the bottom up... IMO

Enjoy the Forum...


Jerry

Click to expand...

Thanks for the brick tip!

Its a patented technique with the razor blades, you stack them WITHOUT spacers, as close as possible, and then mount it in a box. The knife edges diffract the light and the box contains it. Graphite is suprisingly reflective at 445, but will work just fine at 1 watt. Graphite with flat black krylon on it as a adsorber, works well.

Steve

LSRFAQ said:

Its a patented technique with the razor blades, you stack them WITHOUT spacers, as close as possible, and then mount it in a box. The knife edges diffract the light and the box contains it. Graphite is suprisingly reflective at 445, but will work just fine at 1 watt. Graphite with flat black krylon on it as a adsorber, works well.

Steve

Click to expand...

Thanks! I ordered a graphite block to mill yesterday and will go in search of some flat black krylon. Is it safe to assume you mean the paint?

If i can give you a suggestion, for the beam blocker .....

Regardless what you decide to use, or what paint you place on it, remember that a flat surface is ..... well, flat ..... and can always reflect something undesired around .....

I suggest you to take a block of whatever you want, and make a hole in it ..... a simple 15 or 20 mm diameter hole, deep 40 or 50 mm, with the bottom "V" shaped, as any drill bit left naturally ..... and to shine the beam to block inside it.

So, regardless the material or surface or painting, there's much less possibility that the reflections go around ..... just as example, if you take a piece of refractary brick (the ones used for build fire places), find someone that can drill a hole in it, also irregular, and then paint it, including inside the hole, with high temperature matte black paint, this become a very efficent and cheap beam blocker .....

That was in fact the plan. Thanks though!