Laser collminator.

[bmitchell82]

Well im not overly sure this has been covered yet in the forums (more than likely). Im a "impoverished" uni student and sometimes i don't quite have the money to do what i need to do. So i have put my handy hands to work!

With all the talk about people buying these little suckers and then having to make them right i said to myself, really all they are using is the bits and pieces and then making them all good by aligning them.

I will post some pictures of what i have done a small bit of trial and error (see butter bolts.! :( ) but the over all gist of it is I have whipped down to bunnings and grabbed a piece of 1.25" x 1.5mm tubing and basically followed the same idea as what i have seen in the models.

Ive also cut out a 45 deg viewing plate with a slot behind it to make a thin panel to allow a more accurate collmination effort by allowing the laser to come back onto itself and a set of 6 alignment screws to hold and make sure the laser is dead eye d1c4. so far the cost for this is

A. Time
B. $9 worth of materials. which included 1 meter of the tubing.
C. a 8 dollar pen style laser pointer >1mW from singapore!

If anybody has anything that i should add to this or ideas/ and or past projects from obsessive tinker'ers like me let me know ! :D please :)

[drmorbius]

Haven't done it myself, but I must admit I was gobsmacked when I opened my collimator to find a discount store laser pen mounted inside :rolleyes:. My first thought was "I could've made one of these myself"... so you're on the right track.

The hard part will be designing a mount that will keep the laser in place, yet allow for adjustment. Whatever you use, you'll want it to be solid so you don't end up having to collimate the collimator between uses. Not that it's hard, just time-consuming.

I'll be very interested to see the end result... keep us posted... and feel free to ask questions. They're a clever lot in these forums. ;)

[bmitchell82]

Well i got the first prototype sorted today whacked it into the old blue as i lovingly call her and guess what my suspect double image is ... you guessed it MIS CULMINATION funny thing that. :)

So how did i do it.!?

as i said before the pipe that i got from bunnings was thankfully right on the money, a slight bit of sanding and it slides in and out of the ep holder snugly!

Using a hack saw and in no delicate matter i whacked out a hole so i could see the laser when it comes back onto itself.

Next using 6 4mm nut and bolt combinations each set at 120 degrees away from each other and 50mm apart from the each 3 set tapped out a thread allowing the bolts to slide on in with your fingers. A seventh finer bolt was installed so that i could screw it in to hold the laser on :) very nifty i thinks!

Then using a V block as discribed by the forums, i used the lecture theater projector screen some 30+ meters away and then slowly adjusted it until the green dot didn't move any more so that for me is in culmination enough.

the thing is tight as and allows for that "laser culmination" that is easy enough to follow.! Backed up by my trusty film canister cheshire :D all a student needs.! Ill report back tonight on the star tests...

remembering that its a DSE special using 4/5ths of the mirror that is only 114mm the best part about it and the most expensive part is the Mead series 5000 ep's (brand new old blue is worth $99.95) I'm pleased when i can see the Jewel box.!

[bmitchell82]

Well there it is fellas! thats the roughy easy as to make and i might submit it to iceman in a word document for all to fiddle with. Open source i says.

Picture 1.
looking down the barrel

Picture 2.
Laser on old blues primary

Picture 3.
reflection of laser onto the front of the laser pointer.! quick easy and done.

Old blues rack and pinion focuser is pretty sloppy, when collminated at about 40-60 degrees elevation the green dot lays directly on center point mark.

So yay for unistudent :D

[drmorbius]

Well done mate :thumbsup:

You should package this info up into a short tutorial and get Mike to post it in the articles section...

[erick]

Nice job, Brendan! :thumbsup: