Page 1 of 2

Am I the only one nervous about the alignment task?

PostPosted: Fri Aug 24, 2012 2:59 am
by Bitdude
I'm excited about building the laser. But also concerned about the alignment procedures and or mishaps as one of the builders had with his shop printer getting "holded".

Among the thoughts of all the great stuff I can "cut" looms the occasional worry that I will somehow make head line news "Amateur ninny light sabers his own arm off while..."

Bob

Re: Am I the only one nervous about the alignment task?

PostPosted: Fri Aug 24, 2012 3:40 am
by greenvandan
Have you seen this post http://www.buildlog.net/forum/viewtopic.php?f=14&t=147#p530?

There's a lot of good information there, including using a block of wood to check where the laser's hitting (so as to avoid holes in random shop equipment). I haven't gotten to the alignment part yet but I'm not stressed about it, just needs to be approached methodically and carefully.

BTW I'm in MD too, nice to see another 2.X laser close by

Re: Am I the only one nervous about the alignment task?

PostPosted: Fri Aug 24, 2012 12:38 pm
by Bitdude
I did read that one and some others. Active imagination ;-) Especialy after reading the holed printer incident.

BTW I'm in MD too, nice to see another 2.X laser close by


Technically we are close, but I'm at the other end of the state. Allegany County in western MD.

Bob

Re: Am I the only one nervous about the alignment task?

PostPosted: Sat Aug 25, 2012 5:50 am
by awesomenesser
It really isn't a very difficult thing to do. It does take a good amount of time if you want to make it perfect (but that isn't really necessary).

One thing that I did that was a big help was to use dymo printer labels. (They are basically thermal stickers) Set the laser to the lowest you can get it and still make a mark and just stick the labels onto the lens holder frame and tap the fire button to make a black mark.

I thought the hardest part was actually tightening the nuts after I got it all lined up without adjusting the mirrors even further.

Back to the part about not having to make it absolutely perfect. Remember that the lens has a designated focal point. As long as the laser is perpendicular to the lens face then it has to pass through the focal point. (I included a simple over exaggerated drawing)

P1030478.JPG
Some simple physics...


I would still try to get it as close as you can but for example if you are + or - 1mm from dead center with a 50mm focal length lens it will only be around 1 degree off (I would say that your gantry head has a worse tolerance).

Re: Am I the only one nervous about the alignment task?

PostPosted: Sat Aug 25, 2012 10:04 am
by evokanivo
So I'm embarrassed to admit this, but oh well. I literally hit myself in the left hand with the laser while pressing the "test" button with my right. I was in the process of aligning the mirrors. Anyway, it left me with a burn, but no a big deal. I'll leave other *worse* stories for later. So as long as you wear your safety goggles, you can't go THAT wrong.

Re: Am I the only one nervous about the alignment task?

PostPosted: Sat Aug 25, 2012 12:51 pm
by bdring
Nice white board picture.

It shows that an off axis beam still hits the same focal point, but the cuts will be at an angle. If you are cutting anything thick, the edge will not be square.

PS: Love the dymo idea.

Re: Am I the only one nervous about the alignment task?

PostPosted: Sat Aug 25, 2012 1:09 pm
by awesomenesser
evokanivo wrote:So I'm embarrassed to admit this, but oh well. I literally hit myself in the left hand with the laser while pressing the "test" button with my right. I was in the process of aligning the mirrors. Anyway, it left me with a burn, but no a big deal. I'll leave other *worse* stories for later. So as long as you wear your safety goggles, you can't go THAT wrong.


I have done it before with nearly full power while I was trying to square up my gantry head... I still have a slight mark on my hand.

Re: Am I the only one nervous about the alignment task?

PostPosted: Sun Aug 26, 2012 5:48 pm
by Bitdude
Thanks for all the input (stories).

I'm looking to build this over the winter and I'm reading all the material and gathering parts.

I'm sure everyone has seen this one.

Image

Make you wonder about the metal cutting lasers that operate in open air as commented about in another thread.

Bob

Re: Am I the only one nervous about the alignment task?

PostPosted: Sun Aug 26, 2012 11:53 pm
by Bitdude
Thanks for the diagram!!

Bob

Re: Am I the only one nervous about the alignment task?

PostPosted: Mon Aug 27, 2012 3:08 pm
by Chankster
scarylaser.gif