I am almost done with my custom design...

I am almost done with my custom Flood-to-throw design, but I need to find out what is permissible in this section of the forums.

I have a machinist that can do work for me, but I don't know if he can thread as well as the experts here. Dies and taps for the 1+ inch diameters are stupidly expensive, and I can't justify them for a one-off flashlight.

So, if I share my design with pictures and what not, can I ask for bidders to help out with the threading portion alone? Or, would this get turned down because they would want to make the entire flashlight?

The reason I ask is that my machinist is local, and virtually family. I really want to be there as he machines so that we can test-fit and tweek slowly, and be creative together. However, I can visualize the nearly-completed flashlight getting ruined once the threading begins.

Some advice would be very helpful.

Some info: The design is in Solidworks, which I use every day. I would be able to supply dimensioned prints with a bill of material to whatever degree is required.

If this thread drums up some interest, I'll throw some screen caps in here. Or... perhaps screen caps need to be first. LOL..... I guess I'll learn.

Thanks!
MG lovecpf

There is no reason why you should not ask if someone here can help you with this - in fact with this thread, that is virtually what you are doing.

What a machinist here might want to charge you would be between you and him. Negotiations about charges should not take place in public in this thread - that would be best dealt with by PM or e-mail.

Ok, thanks, DM51.

So.... post screenies of my design here then?

Pictured below:
Orange battery is this 26650 from batteryspace.
Lens
Retaining ring holding the lens in place is from McMaster, item 92370A185
20mm star board, eventually will of course have an XPG R5.
The star will be fastened to the copper slug, which will allow for adjustement via four 0-80 set screws. This is to bring the LED into perfect focuse when in the focused position.
I haven't worked on the tail design yet, but I'm planning on a nice reverse clicky with rubber boot. Nothing fancy, but I do plan to be able to tail stand for ceiling bounce.

I know there are several things out of position and still need to be refined, but this is the general idea.



Flood position:

Focused position

Excellent drawings - it looks very nice indeed. So the idea is that in the closed (short) position, you have a flood beam, and when you pull out the bezel to the focused position it is a collimated pencil beam? Or have I got that completely wrong?

DM51 said:

Excellent drawings - it looks very nice indeed. So the idea is that in the closed (short) position, you have a flood beam, and when you pull out the bezel to the focused position it is a collimated pencil beam? Or have I got that completely wrong?

Click to expand...

You got it. Classic flood-to-throw concept.

Beautiful drawings! :thumbsup:

Cool!

Nice If you are going to make 1, maybe consider making some more? I know from experience when maching and fabricating stuff by the time you've got 1 done you may as well make several of the same part as it takes much less time. I'm sure material costs won't break the bank, it's the labour and machinery that sets you back. Does you friend work for beer, I know I have done. lol

Then scale it up and drop an SST-90 in there! :thumbsup:

Paul.

Yep and offer them for sale here..

Paul Baldwin said:

Nice If you are going to make 1, maybe consider making some more? I know from experience when maching and fabricating stuff by the time you've got 1 done you may as well make several of the same part as it takes much less time. I'm sure material costs won't break the bank, it's the labour and machinery that sets you back. Does you friend work for beer, I know I have done. lol

Then scale it up and drop an SST-90 in there! :thumbsup:

Paul.

Click to expand...

I'll definitely talk this over with my machinist friend. And, I agree that making more than one makes sense.

thx!

I'm struggling to find optional aspheric lenses. I have room for a larger OD, but I stll need a fairly tight focal length.

Any suggestions?

http://www.edmundoptics.com/onlinecatalog/browse.cfm?categoryid=11#header

About 1/2 way down you will find the aspherics. Prices are kinda steep but Edmund is good for getting low volume stuff. If you need more volume then email me.

BTW Nice design! :thumbsup:

KuKu427 said:

http://www.edmundoptics.com/onlinecatalog/browse.cfm?categoryid=11#header

About 1/2 way down you will find the aspherics. Prices are kinda steep but Edmund is good for getting low volume stuff. If you need more volume then email me.

BTW Nice design! :thumbsup:

Click to expand...

Thanks!

I found some interesting candidates way down near the bottom of the aspherics section.
Aspheric Lens 27mm Diameter x 13mm FL
NT43-987 $33.00

and
Aspheric Lens 35mm Diameter x 26.2mm FL
NT43-988 $40.00

They sure are expensive, but the back focal lengths being as short as they are, these are pretty darn good for a flood-to-throw. Would you agree?

Also interesting:
http://www.thorlabs.com/thorProduct.cfm?partNumber=ACL3026

19.3mm back focus, $20.00.

SCORE!

MoreGooder said:

Thanks!
I found some interesting candidates way down near the bottom of the aspherics section.
Aspheric Lens 27mm Diameter x 13mm FL
NT43-987 $33.00
and
Aspheric Lens 35mm Diameter x 26.2mm FL
NT43-988 $40.00
They sure are expensive, but the back focal lengths being as short as they are, these are pretty darn good for a flood-to-throw. Would you agree?

Click to expand...

Yup, Just a reminder, the shorter the focal length, the less light you lose when you are in the focused position. I remember Edmund had sapphire lenses... can't seem to find them now...:duh2:

I have got to learn how to use AutoCAD one of these days.

If I could make two suggestions:

1. When the light is in "throw" mode, a lot of lumens will be wasted against the side walls of the tube because the focusing lense will be so far away from the emitter. I don't know the math necessary to make this work, but maybe it would be better to have one lense permanently located near the emitter, to pre-focus the beam so it doesn't hit the sides of the tube, and have a second lense at the front of the tube to focus the beam more or spread it out as the focal length changes.

2. Consider triple- or quadruple-threading the head and body, like the way a Mini-Maglite head is threaded, so a single turn of the head will change the beam focus more than it would if the parts were single-threaded. That way users won't have to twist the head over and over and over to change from "flood" mode to "throw" mode.

Looks good man. If you can swing a titanium version, this might be the first non-McGizmo light I'll buy in quite some time. :thumbsup:

fyrstormer said:

I have got to learn how to use AutoCAD one of these days.

If I could make two suggestions:

1. When the light is in "throw" mode, a lot of lumens will be wasted against the side walls of the tube because the focusing lense will be so far away from the emitter. I don't know the math necessary to make this work, but maybe it would be better to have one lense permanently located near the emitter, to pre-focus the beam so it doesn't hit the sides of the tube, and have a second lense at the front of the tube to focus the beam more or spread it out as the focal length changes.

2. Consider triple- or quadruple-threading the head and body, like the way a Mini-Maglite head is threaded, so a single turn of the head will change the beam focus more than it would if the parts were single-threaded. That way users won't have to twist the head over and over and over to change from "flood" mode to "throw" mode.

Looks good man. If you can swing a titanium version, this might be the first non-McGizmo light I'll buy in quite some time. :thumbsup:

Click to expand...

Well, I wouldn't even attempt this in AutoCAD. (I refer to that as ManualCAD). I'm using Solidworks. All of those fancy cutaway views and iso's come free with a simple click of the mouse. Solidworks RULES.

The primary goal of this flashlight is to provide maximum, beautifully homogenious flood, actually. The fact that it will be focusable to throw light will merely be a bonus. I can't imagine why it won't do both really well.

Threading is really something I'm concerned about. That is why this intitial design uses stainless steel retaining rings to hold the lens in position. But, now I'm second guessing this design. I am concerned about how the retaining rings are installed/uninstalled. If it requires a squeeze or twist with a pair of needle nose pliers, you can imagine how scratched up it would get. Threads would definitely be superior. Again, it's all up to my tooling guy's skills and capabilities. Perhaps the retainin ring would be really handy for the lens back-stop since it wouldn't be removed often, if at all.

To me, the primary features that I wanted was maximum run time (thus the 26650 battery), maximum flood (thus the aspherical lens), adequate thermal heatsinking (thus the copper slug) for a 3.5-ish to 4W power consumption emitter. I do have 0-80 set screws in the design to refine the position of the slug in the body to adjust the focus simply because it's possible to do so. This does indeed impact the water resistance of the design.

Oh, and I hate twist focus. Simple push-pull is far easier to implement, easier to tweak the focus, and more intuitive to understand (Now, which way do I twist to focus?). I would argue that if it were'nt for the m*g light, twist focus would be an oddity in flashlight design.

KuKu427 said:

Yup, Just a reminder, the shorter the focal length, the less light you lose when you are in the focused position. I remember Edmund had sapphire lenses... can't seem to find them now...:duh2:

Click to expand...

Yup! +1

The only downside to a very tight focus is that you have to be more precise with the focus position. In other words, if flood-to-throw was only 15mm of travel, you would need maybe +/-0.5mm of precision on focus position before you'd notice that it was out of focus. Conversly, a long focal length means that same +/-0.5mm would be completely adequate. (ok, so my numbers are imaginary, but the concept is what's important).

MoreGooder said:

That is why this intitial design uses stainless steel retaining rings to hold the lens in position. But, now I'm second guessing this design. I am concerned about how the retaining rings are installed/uninstalled. If it requires a squeeze or twist with a pair of needle nose pliers, you can imagine how scratched up it would get. Threads would definitely be superior. Again, it's all up to my tooling guy's skills and capabilities. Perhaps the retainin ring would be really handy for the lens back-stop since it wouldn't be removed often, if at all.

Click to expand...

MoreGooder said:

Yup! +1
The only downside to a very tight focus is that you have to be more precise with the focus position. In other words, if flood-to-throw was only 15mm of travel, you would need maybe +/-0.5mm of precision on focus position before you'd notice that it was out of focus. Conversly, a long focal length means that same +/-0.5mm would be completely adequate. (ok, so my numbers are imaginary, but the concept is what's important).

Click to expand...

How about machining a ledge for the aspheric and an o-ring to sit on and a screw down bezel? You can also up the size on the aspheric if you do that and get more efficiency in throw mode.

Your concept is correct. There shouldn't be any problem with getting the machined parts to the exact length, it's the mounting of the PCB/LED to the pill that can cause minute differences in focal length, and even those are minor. Assuming the aspheric is sitting on an o-ring, these minor inaccuracies in focal length can be compensated for by slightly over/under tightening the bezel which is more accessible than the set screws. Um... set screws? I though it would be best for the PCB to have as much contact with the slug?

IMHO a pre-focusing lense will increase the overall length of the light both in focused and unfocused mode. The loss of light via the pre-focus lens will probably cancel out any gains.