Mitsubishi ML520G71...Red Holy Grail or Flashlight Fail ??

[planters]

I disagree with cdbeam. I think there will be some crosstalk between focus and an X/Y lens adjustment especially when the thread is a little stiff as it is when using tape to eliminate wobble. I am still an advocate for screw type adjustments for centration because as the lens is rotated into focus and periodically adjusted, the centration may have to be tweaked and a "set it and forget it" jig may be cumbersome.

Copper is a bitch to work with. I love aluminum, but it does not thread as well as brass. I don't think thermal mass or thermal transfer is a significant problem for these non-pointer bench style setups.

I do not think there will be any change in PO. I can't think of a mechanism for this unless the fixed mounting was so off that the diode output was being clipped. With 2-3 mm lenses that much misalignment should be causing a lot of beam distortion. But, we'll see.

[bhwollen]

IMHO I think that the lens adjustable mount will be a better alternative because:
A) Looks easier to align
B) Better thermal transfer between diode module and the block of material
C) once you have the diode aligned perfectly horizontal you don't have to touch it again
D) It looks freaking awesome? lol

Either way, no point arguing about this, each one has their advantages and disadvantages. Personal preference

[CDBEAM]

Yikes...." Looks...like I didit again "....another spirited debate on yet another topic..." The lowly LD Mount " !!! I will start a new thread...where we can explore the nuance of design !!! I assume (and hope) LSP,Logsquared,Planters and others will weigh in. ONE thing we can agree on...some type of adjustabillity is desireable with these short fL Collimation lenses !! Stay tuned !! BEAM

Note...One thing I should mention that I have not noted before....with the LDALM design...the Lens position disc was left to rise ever so slightly past the main block front facia. This means...that once you set your X-Y position...you can then apply a final torque to the capture plate bolts...thus locking in the X-Y position. So...when the collimation lens is periodically adjusted...your X-Y is not compromised.

[steve-o]

Just thinking err.. drawing out loud again..



-edit- I suppose I’ll add an explanation if anyone’s interested
The steel Lens plate will have over-size holes drilled for X-Y manual adjustment to center the lens in front of the diode. There will be 4 screws (only 2 showing in cut-away side-view). The Z-axis (focus) adjustment will be accomplished by tightening/ loosening the screws. The thermal barrier (to keep heat away from the lens) will be a thin semi-flexible gasket material (shown in blue) surrounding / sealing the space between the aluminum/ brass diode holder and lens-plate. There will only be a few thousandths of an inch adjustment available, so it’ll have to be pretty close tolerance from the beginning. This is an adjustable lens vs adjustable diode setup because I also think thermal heat transfer from the diode to the base is important. I will be attempting to build a couple of these in my *machine shop* (lol) soon.

[CDBEAM]

Yes...Yes...Working on a similar design....incorporating the pocket aspect from Dave's standard brass mount...with the X-Y positioning/lock down attributes of the LDALM.. See attached drawing LDALM CP V1. This idea was originally suggested by Kiyoukan. I think I may prefer this...as the LD can now be changed out...with no damage to the diode. Pressing in is one thing..removal is another in an Axiz module....where damage could occur to the diode. In this regard...Dave's pocket aspect is perfect...and also allows for rotational adjustment. Now couple that with collimation lens positioning+ lock down...my current favorite. More fun !! BEAM


Note: As a Christian...I thought it appropriate to post a link to the real " Sermon on the Mount ". Take note of the biblical reference to " The mote and the beam " !! ....http://en.wikipedia.org/wiki/Sermon_on_the_Mount...May God bless and keep your eyes safe...BEAM

[steve-o]

In this regard...Dave's pocket aspect is perfect...and also allows for rotational adjustment. Now couple that with collimation lens positioning+ lock down...my current favorite. More fun !! BEAM

Which Dave's LD/ lens mount? This one? (the only one I saw on his website)

Daves LD mounts.jpg

[CDBEAM]

Hey Steve...yes...that is the one I am refering to from LSP. The rectangular plate on the back side captures and locks the LD in position via the four (4) allen bolts. Perfect for the 445 LD. The M9 threads are just right...snug...but not tight. I still like brass...even tho it has slower thermal transfer than Ally !!

I will machine a proto of the LDALM CP V3 sometime this week...from brass !!...would like to go with 100TPI for the X-Y adjustment
bolts !!

BEAM

[steve-o]

100TPI? Wow. That's sum fine tunin' adjustment there .. Awesome

[CDBEAM]

Think I'll go with a M3 fine thread = M3 x .35. To me...this is the right diameter...'bout 1/2 the thickness of the lens disc...and this equates to 72.57 TPI....not as fine as 100 TPI....but...much improved over the 40 TPI of the 4-40. Any real machinist's out there...feel free to comment on this...as I am a "hack" machinist...at best !!

BEAM

[LaNeK779]

i'd like to note that the diode mount listed above works ok for collimators up to around 4mm
dave has another diode holder that allows for diode centering, which many people (and me)have tried with the 2.9 and 2.0mm FL lenses

so, cdbeam, the mount you picture is not up to the task, but there is another dave-mount for this
just imagine that the 5.6mm "nest" that the diode sits in is not in the big chunck of brass, it is in the small retaining plate with the four screws, so the diode can be moved about a bit