assembling diode+collimator inside housing

[Maltes]

I have two questions about whats mentioned in the title.
1) How do you determine the collimator sweetspot distance from the diode? What can I use to secure the collimator barell in place after I get the right distance?
2) How to take out or rotate the diode which is already snugly fitinside the housing, without using the pins as handles and breaking them?

[dkumpula]

For most entertainment purposes, you generally want to adjust the colimation lens so that it is the best at a long throw. (There are several exceptions to this rule depending on personal preference/safety issues/fitting beams on galvo mirrors, etc.) As a general rule, you set up a bounce mirror to extend your throw as far as you can and adjust your beam. Note: In many cases you have to take off the thumb ring to sufficiently focus the beam as the thumb ring prevents you from getting the lens close enough to the diode. This varies based on specifics of your diode and the type of colimation lens you are using.

To keep your colimation lens in place, you can use thread lock (the light duty stuff) or plumber's adhesive tape. I use the later, generally wrapping two full turns of a 4mm length around the far end of the lens threads (so it goes in easy at first and then tightens up when you hit the tape). Pro-tip: Wrap the tape counterclockwise when looking at the exit end of the colimation lens. This keeps the tape from bunching up as you screw it in.

Regarding question #2, it depends on how the diode is mounted. If you are using pre-assembled cylindrical mounts that fit in the SK12 rail shaft supports, you simply loosen the bolt and rotate the cylindrical module. If you have the common brass mounts held in place with 4 small screws, you can either loosen the screws and gently rotate the diode. If you have something in there like heat-shrink-tubing that prevents the diode from rotating, you can remove the diode and back plate and manually turn the diode itself or if you simply need to rotate it 90degrees, rotate the back-plate 90 degrees and put it back together.

-David

[Maltes]

For most entertainment purposes, you generally want to adjust the colimation lens so that it is the best at a long throw.

What does best mean here? Smallest profile?

In many cases you have to take off the thumb ring to sufficiently focus the beam as the thumb ring prevents you from getting the lens close enough to the diode.

I have ordered several G2 lens in black barrels and 3 element glass lens in brass colored barrels. I'm not sure which part the thumb ring is

To keep your colimation lens in place, you can use thread lock (the light duty stuff) or plumber's adhesive tape. I use the later, generally wrapping two full turns of a 4mm length around the far end of the lens threads (so it goes in easy at first and then tightens up when you hit the tape). Pro-tip: Wrap the tape counterclockwise when looking at the exit end of the colimation lens. This keeps the tape from bunching up as you screw it in.

Thanks for the advice.

If you have the common brass mounts held in place with 4 small screws, you can either loosen the screws and gently rotate the diode.

Okay, but how? I can use the pins as handles when rotating but they seem fragile.
Specifically I have put a NDB7875 diode in a typical brass block mount and it had some residue on it (probably some heatsink material) which made it a tight fit and a bit hard to take out or rotate.

[Diachi]

I have ordered several G2 lens in black barrels and 3 element glass lens in brass colored barrels. I'm not sure which part the thumb ring is

The silver part on the end of the lens assembly as pictured above would be the thumb ring.

[Maltes]

I see, none came with one

[Maltes]

For most entertainment purposes, you generally want to adjust the colimation lens so that it is the best at a long throw.

I'm still unsure what this means.

[dkumpula]

It means that you want to focus the lens so that the beam looks smallest / focused at as far a distance as you can set up for testing/adjusting.

[kecked]

Turn the lens until the beam is as small as possible on the wall you are projecting it on. If you will be moving the projector around then do as he says above and focus on the farthest distance you can see. The beam closer can be smaller than this far distance focus so that is why I say this.

[Maltes]

I see, thank you. I can use a wall on an abandoned building at about a 1 mile distance and use my telescope while adjusting, that should work.

[catalanjo]

Might be a bit safer to use about 10metres so no one gets in the way, one mile seems like overkill to me !
Cheers