H51/H51w mod: flip-away diffuser

[turboslug]

This is pretty neat. Very ingenuitive! This gives me a great idea for one of my lights. I just might have to steel your idea. I think you should consider developing a prototype for remarketing commercially. I am sure it would sell, I would buy one. Thank you for posting.

 

[gcbryan]

Ted, one more questions...what is that white stuff between the collar and the headlamp head? Is that caulk to fit the collar to the head?

 

[tedh]

gcbryan, one of the advantages to the new Fenix design, with its thinner collar, is you may not need a "gasket" (blue cord in my prototype) like I did. I suspect a the right number of turns of electrical tape around the body of the light will provide an exact fit, so the diffuser lies flat on the bezel. I didn't have any trouble putting the light in the silicone holder, it wasn't an issue at all. The white stuff is 3M Ultra Flex. It's a two part urethane adhesive. You mix it like epoxy, but it dries flexible. It's basically used for what you said, caulk to hold the collar in the right position relative to the head.

Turboslug, go for it! And post a picture of what you did, I'll be curious how your diffuser comes out!

Ted

 

[gcbryan]

I got my H51 today. I haven't had a chance to use it at night yet but I'm pleased so far. It has a hot spot (of course) but isn't harsh looking...good OP reflector I guess.

I rigged up something with the flip diffuser. I am not sure at all that I want to leave it on as everything I did can be undone without messing up the finish on the headlamp. The diffusion effect could be smoother.

I used an o-ring around the body just next to the head as a spacer and then clipped the collar on and held it in place with thin strips of electrical tape. I used plumbers pipe fitting tape on this portion of the body tube as protection and to build it up a bit since there is a ridge there.

I can still slide or position the diffuser to get to the proper spot. It seems the diffuser is slightly too small and I get a bit of light coming out due to size. I also can't get it flat and didn't glue anything on to the diffuser so when wearing it I get glare. Gluing an o-ring onto the diffuser would probably fix the glare issue.

Since I like this beam and don't see needing to use diffusion while hiking the diffuser would only be for later in camp. I have a H51f for that so I may take the diffuser off just to keep things simple.

If this were my only light then I would probably stay with the diffuser. It's a nice idea and a good call on your part. It would have been nice for Zebralight to have designed a sturdy form fitting clip-on diffuser for this model.

Anyway, for anyone who wants to try this diffuser out without going to too much trouble it can be fitted with just tape. Ted, I can also see why you are thinking about drilling some of the diffuser material out and replacing it with something smoother.

 

[johnmeyer]

I purchased the Fenix AD401 diffuser, but found that it has indeed changed from what was described in the OP. I decided that to make it work that I would shim one side of the diffuser's mounting ring. I looked around the house and found some Felt Gard pads that are designed to go on the bottom of furniture legs to keep the furniture from leaving marks on hardwood floors. Here's what it looks like:

I cut a small strip off this material and then used an Exacto knife and also a small set of dykes that I use to cut small electrical wires to make the material conform somewhat to the ridge that goes around the flashlight near the lens. The diffuser collar fit over this very nicely, but still felt like it might slip or move if the flashlight were bumped or handled roughly. Since I am not planning to remove the diffuser, I used a little hot glue to keep the collar from slipping. This is what the result looks like:

This obviously doesn't look too professional, so I wrapped a little electrical tape around everything, and then mounted the flashlight in the headband holder. I might eventually replace the electricians tape with heatshrink tubing. Here's the final result:

 

[gcbryan]

Does the diffuser lay flat against the light and have you tried using it outside yet and is there any glare?

 

[johnmeyer]

Does the diffuser lay flat against the light and have you tried using it outside yet and is there any glare?

No, it does not lay flat against the light's lens, and I don't think that is possible. But, it really doesn't make any difference. I checked before I did the mounting to see what difference in diffusion, intensity, etc. that I got with the diffuser slightly away from the lens, compared to having it flush against the lens. It didn't make any difference. This shows the "fit:"

However, one problem with this diffuser is that the edges of the diffuser itself are made of the same clear material as the diffuser and as a result, this edge gets very bright, and this bright light is directly at the top of my field of vision when I wear the headlamp. Today I plan to take a Sharpie pen and paint the bottom edge of the diffuser black in order to get rid of this problem.

If the light leaking from the gap is still an issue (it is a small fraction of the amount of light conducted to the edge of the lens that I'm going to block by painting with the Sharpie), I'll attach a small rubber washer.

 

[gcbryan]

When I tried something similar I had glare that was bothersome to me when I was outside and it was totally dark. It wasn't so much an issue when using it with some ambient light.

 

[michman]

This is a great mod!