Making a honeycomb flash filter for telescopic sight for less than 6 dollars

Materials
Black plastic cocktail straws
PVC Insulating tape
Sunshade of the telescopic sight (scope) you want to make stealthier
A helping hand
A sharp serrated knife
My box of 400 straws could make at least 15 filters assuming each straw is 3 times longer than the filter depth and a bunch of 80 straws compressed matches the inside diameter of the sunshade you're protecting. Total cost = your time + about 6 dollars for 15!
If you have a choice, I would choose larger diameter straws than smaller, because intuitively this improves the light transmission (there will be less interstitial points with larger straws which should allow a better ratio than smaller straws).
There is another trade off in the length of straws (equates to depth of filter). The longer the straws, the narrower the acceptance angle but perhaps the darker the picture (it's not easy to ensure they are exactly inline or slightly skew. The shorter, the less this matters). I have settled on about 15mm depth which seems to give good results.
Camera Sony HDR PJ260V
I created this video with the KZbin Video Editor ( / editor )

[@RJTINNC]

I have done this project and can give some insight to some questions. You can use very small straws (coffee stir sticks) with no ill effects. Only make the filter about as thick a electrical tape or it will hinder light gathering. I have used this in pitch black other than some street lights and it was crystal clear with no light gathering issues. Also you can adjust the tension of the friction fit by adding more tape. Just make it snug where you have to lightly squeeze it in to fit. Once you have everything complete and adjust for size and such spray some flat black paint over the front and back of the straws. This does few things, it takes any shine away the plastic straws may have, it covers any edge of the tape that may show and it acts like a binder to hold the straws together. Great, cheap, easy project and it works great!!!

[@RobWhittlestone]

GREAT INPUT! And you just proved my worries expressed to +Eric Borders above, wrong. Well done! Cool that you improved on my idea! Best regards, Rob

[@PaulsWackyWorld]

I don't know about you but the recoil of my rifle will eject the straws that are not in contact with the tape.

[@RobWhittlestone]

PaulsWackyWorld I think it depends how much compression you applied to the straws when binding them with the tape. That's why I needed four hands and not just two! To be very straight with you, I haven't actually shot mine yet but will do so soon. What rifle are you using? I could imagine that with a light rifle and a strong cartridge, that could happen more. Try re-binding with more straws added. The ideal is to compress them so they each form a hexagon. Thanks for giving your feedback, Paul! All the best, Rob

[@RobWhittlestone]

PaulsWackyWorld I forgot - Ross McLean (see comments below) glued all the straws together - if all else fails, I'm sure that'll fix it. ATB Rob

[@G_Zero127]

I know this is a 2 year comment but another way to hold the straws from moving with recoil is glue around the sides between 2 sheets of Plexiglas.

[@toddhardin7169]

@@G_Zero127 Depending on the magnification of the scope, one would want to be sure to have any additional optic added, be it glass or Plexi, to be exactly orthogonal to the sight picture in order to prevent refraction that would skew the zero of the scope

[@toddhardin7169]

A low temp bake of the sunshade would also work instead of using glue and prevent a mess, although one would want to start low and increment temp slowly to prevent warping the straws.

[@mk84ldb]

Each time he coughed, I took a shot of Jack Daniel's. Now I go to AA meetings.

[@sparklauerei1]

this is lovely asmr content :D

[@rossmclean8315]

Hi, I have made my own sunshade with the straws method (great idea - thanks!), but as a final touch, glued them all together with modellers plastic glue(comes with a precision applicator)

[@RobWhittlestone]

Great idea, Ross! Thanks for letting us know! All the best, Rob

[@hyperhektor7733]

it looks promising cool but today i tried it out and got disapointed. The issue is the optical resoloution of the scope will be reduced a lot. The cause of this effect is that the black straws have shiny surface inside and will mess with the optics (reduces the contrast extreme). A temporary alternative is to use 6mm (1/4") heatshrink tubing instead of straws since they are less shiny inside. A better alternative would be to use 2 grid plates with round holes 1-2 inch apart in series, that would reduce the shiny glare effect by 99% since the 2 plates are very thin (2x 1/25") compared to the lengh of the straws (2inch lengh in the video?)

[@RobWhittlestone]

That's an interesting suggestion! Can you make a video to show what you mean? I am always happy to learn something! Thanks for viewing and commenting. All the best, Rob

[@hyperhektor7733]

@@RobWhittlestone do you mean the heatshrink idea or the metal mesh/perforated sheeting idea?

[@kctyphoon]

“I think the length is important” That’s what she said ;) Great video.. I’m also curious how it would appear through the scope if you filled the entire length of the sunshade with the straws. The longer the straws, the smaller the degree of angle that would allow for reflection, i would assume. Also - misting the straws with some matte black spray paint or primer might knock the gloss down a bit.

[@biscuit43sea]

Very informative video. Thank you for posting this. Have you noticed any negative effects on the flash filter caused by the rifle recoil? Such as slippage in the straws?

[@RobWhittlestone]

Hi biscuit43sea! Good question! Our public ranges are closed for winter and I haven't been to a private one yet. If I notice anything I'll let you know, but I'm not expecting any - the mass of each straw is extremely small and the compression force they are under comparitively large.

[@gtj2020]

Quite ingenious idea and use of materials... cheers!

[@RobWhittlestone]

Thank you very much! Glad you like it! All the best, Rob

[@lloyddotimas6302]

I regret that I couldn't increment the number of likes any more than one

[@RobWhittlestone]

Hahaha! Very kind! I have an idea - tell all your friends to "like" it too! :-) All the best, Rob

[@lloyddotimas6302]

I'll sure will

[@maureencoss6962]

good video , butt the dude takessssssssss issssss time and speek very very very..... wait for it , slooowwwwwwly......

[@RobWhittlestone]

Yes, you're right Maureen. I have been living in Switzerland for 25 years and speak French, German and Italian as well as my mothertongue, English. I grew up speaking English to non-mothertongue speakers so have learned to speak slowly and clearly. I hope there was no word I spoke you didn't understand, because that is my aim. Another fact is that unfortunately there are not so many people to speak to in my mother-tongue English here in Switzerland, so I find it increasingly difficult to find some words I wouldn't use in family life. I am a also a scientist by training and try to only use the correct word and never ever say anything I don't mean. This has the impact that I always think hard about what I am saying, whichever language I use. If you like, you can use KZbin settings to play the video at twice the speed. Thankfully it doesn't increase the frequency of the voice to mouse or bat-like levels. :-) I'm glad you liked the video despite my slow (but hopefully clear) speech. Best regards, Rob

[@iCanHazTwentyLetters]

Thank you for this nice tutorial. Really helpful. I think doing this with a couple more straws in the tube, it really will become honeycomb. (but really the circle shapes are just as good). Next step is to add glue ;)

[@RobWhittlestone]

Yes indeed! I think the tighter the packing, the closer the straws will be shaped like a hexagon. Ross Mclean (see below) did use glue with a precision applicator. I'm curious how his turned out! Why don't you upload a video from your smartphone as a Video Reply to show us how it succeeded? That would be cool! Good luck and all the best, Rob

[@iCanHazTwentyLetters]

I would also like to see Ross´ version. If I do this it wouldnt be anytime soon though. First gotta figure out the cheek rest and stock.

[@lfcmarkeb7124]

about 15 mins longer than need be lol, but a good work around. quite obvious when you think about it👍👏

[@davetruther31]

What about adding a anti reflective coating to the straws like the ones used on military sniper systems kill flash? Do you notice that the shiny surface of the straws produce a glare when light hits them just right?

[@hp9mm]

wouldn't it be better super gluing the straws, if you shoot a rifle with this on the scope, won't the straws move under the shock of firing?

[@RobWhittlestone]

Yes, supergluing is a good idea. If I made this into a product, I would want it to be robust and as shockproof as possible.

[@emirjonpg]

Hi again Rob. My scope is Hawke Vantage 4-12x40 AO mil dot. Can I make this flash filter for my scope, is not problem for scope with 4-12x zoom? Regards.

[@RobWhittlestone]

No I don't think so. But try it, it costs so little to make. If you don't like it you can always remove it. Thank you for viewing and commenting! All the best, Rob

[@alfonsorodriguez6437]

Clever idea if your scope has a detachable sunshade, if not, it is almost impossible to implement. At least it will save money for those that have or can fashion a sunshade for their rifle telescopic sights. Why didn't I think of this? Maybe because it was so obvious that it needs someone to think out of the "box". It could also be implemented with smaller diameter straws that will increase its efficiency. Again, an elegant and clever solution as a home made ARD.

[@RobWhittlestone]

Yes, you're right Alfonso! Why not implement some tabs at the side, which could serve to remove it from the scope for when you don't need it? All the best, Rob

[@DonaldStarkweather]

that is brilliant. I love seeing videos of people coming up with clever ways to create your own gear.

[@RobWhittlestone]

+Donald Starkweather Thank you, Donald! I enjoyed making it and it seems it filled a need. All the best, Rob

[@DonaldStarkweather]

+RobWhittlestone if you lay out a long strip of black tape, sticky side up, and line the straws up along it you can roll them up and wrap with another strip of tape and trim to fit. this will prevent the straws in the center from escaping during the firing of the rifle and is much faster and easier than gluing them one by one.

[@RobWhittlestone]

+Donald Starkweather That's a great tip, Donald! Many thanks and all the best! Rob

[@GringoBack]

She was like 'the f is Rob doing with these?' :D Nice tutorial, I am going to make my own filter, but I thought of using these plastic 'beads' (not sure if the right word in English) that children use to put on the board to make images (the black ones only ofc), they are stiff and not too long, glued together should make a hard surface, which is what I have to achieve as I am an airsoft player and are more interested in protecting my red dot sights from BBs.

[@RobWhittlestone]

+GringoBack Ah yes, I think I know the ones you mean. That's a good idea. No need to cut them to length, they are already quite short. You wrote your comment around end of 2015 - have you done it now? Have you made a short video to show us? If not, that would be my suggestion! :-) I am curious to know how it worked. If I remember correctly, the little plastic cylinders ('beads' is also a good name) have quite thick walls. Does this not cut down the light too much? Do let me know. Thanks for viewing and commenting! All the best, Rob

[@TheDelahaye]

Fantastic! Been looking for one 50mm wide for my spotting scope and they're quite pricey! This is ideal for an archetypal Scotsman like me :)

[@RobWhittlestone]

Glad to be of service! :-) All the best, Rob

[@salsarivera]

+Rob Whittlestone Thank you so much brother for the idea and HUGE money saver and for taking your time to share your knowledge I will use this idea thanks again

[@RobWhittlestone]

You're very welcome, Jaime! I'm glad you like it! All the best, Rob

[@freedomofabird]

Great vid Rob. I paid 50 dollars for one from the states about 20 years ago!!

[@RobWhittlestone]

Thanks! I thought they just can't cost that much so I decided to make my own! Many thanks for watching and commenting! All the best, Rob

[@Biffo1262]

Yes I'll make one but surely the fact that have a sunshade obviates the need for an anti-flash filter. I shall be attempting to fit mine to scopes for which I cannot get a sunshade.

[@rainmechanic]

Sunshades do not negate the need for a kill flash.. The purpose of a kill-flash is to prevent glint from coming off your objective lens and giving away your position to the enemy.. A sunshade will only prevent glint at extreme angles since their is more surface area for light to enter. A Kill-flash greatly reduces the light gathering capabilities of a scope and need to be taken off in low light situations. They are two very different things.

[@MrHeuvaladao]

Cool!

[@bushmanuk100]

top video was going to buy one for £15 thanks mate simple idea but very effective

[@RobWhittlestone]

I've seen proper ones (eg. Leupold or other top notch brands) go for £50 (CHF 80) and was horrified at the price. I long had the idea but had extreme difficulty finding large diameter black straws. Finally I happened across them by chance in a clearance sale for about £2.50 for 400!

[@Slay_No_More]

How does this work keeping sun out of your scope? I'm tempted to buy one. The sun blinds me when I shoot in the afternoon, it washes out the targets making it hard to see. Would this help?

[@RobWhittlestone]

+Saint Dick I'm pretty sure it would help. Give it a try! All the best, Rob

[@Slay_No_More]

+RobWhittlestone I ended up trying a similar device and it does indeed help a little, especially when the device is on the longer side. I noticed even putting cardboard tubes over the scopes even help.

[@homersimpsonii5455]

Have you tried or thought about trying the small stirrer straws?? Seems like they would create better filtering, but im not sure they wouldn't obstruct the view or hinder light gathering. Thanks in advance, and thank you for showing this, it will save me some cash.

[@RobWhittlestone]

I'm sure they would also be useful. I think that the smaller the straw, the more straws I would need and the more light will be blocked, because each straw has a finite thickness. If they were infinitely thin, I think it wouldn't make any difference. Unfortunately they would become infinitely fragile too! So straws will probably always have a similar thickness which means that the fewer straws, the better the transmission of light. So I chose fatter straws. Fatter straws compress into a honeycomb (hexagonal cross-section of the cells) easier than stiffer but thinner straws. And there is the fact that these are the ONLY ones I could find! :-) Many thanks for your thoughtful input! All the best, Rob

[@RobWhittlestone]

RobWhittlestone It seems that my worries are not founded! Check out +RJTINNC's input below!

[@emirjonpg]

Nice and so easy, thnx for your video. like and subscribed ;)

[@RobWhittlestone]

Thank you Miri! Best regards, Rob

[@msgajhimelret9496]

Very slick... as long as the inside of the straws don't reflect a lot,,,

[@RobWhittlestone]

It works surprisingly well, especially considering the cost.

[@toddhardin7169]

This is brilliant! Thanks for the idea, I'll be doing this on my long range scope!

[@RobWhittlestone]

Yes, great, try it! It's inexpensive, so if you don't like the result, you didn't spend too much money! I didn't like the price of the official killflashes on the market. Best regards, Rob

[@iamjuiceman]

Love the video but has anyone found a source on these elusive straws? Please post a link if you have so I can apply this knowledge.

[@Biffo1262]

Yours Truly Loads on eBay.

[@jazzhandsparten]

Or coffee straws works too

[@Scarekrow24]

Does the cut length of straw affect field of view at all? I am thinking of doing this to a 44mm obj scope.

[@RobWhittlestone]

Hi Kevin - I think theoretically yes (imagine straws 1m long and 3mm in diameter!) but in practice no (since usually the scope is quite selective about field of view itself anyway) and you cut the straws to only be about 25mm long. Of course if you had 5mm diameter straws cut to only 1mm long, the effect would not be noticeable - I think there must be an optimal balance between straw diameter and length. If you look at the commercially produced ones, they look only about 10mm thick and use a grid of about 3mm. I hope this was useful. All the best, Rob

[@Scarekrow24]

RobWhittlestone lol imagine trying to drink a milkshake with those 1m straws! I will try to make a few at various lengths. I will know my limits if vingetting occurs (like when you use too tall a filter on a very wide angle lens)

[@markdittell]

Brilliant!

[@RobWhittlestone]

+Markd Thanks! All the best, Rob

[@hyperhektor7733]

political incorrect lol , people interested in guns usually dont care about "pi" :D

[@drewstrom1]

It's a sun shade why do you need the honeycomb. The only time the sun should reflect light is if your target is silhouetted by the sun and let's face it you wouldn't be able to see your target at that point.

[@drewstrom1]

Otherwise cool idea.

[@RobWhittlestone]

Drew Strom Thanks Drew! Yes, I agree the sunshade will already produce a degree of selectivity for the reflection. It was the only mechanism I had to hand that would guarantee an easily removable honeycomb filter. If I had had a 10mm-20mm ring that could screw onto the scope instead of the sunshade I would have used that instead. Maybe someone else knows where to source such a thing for a 50mm and a 56mm objective scope... All the best, Rob

[@rainmechanic]

The purpose of a kill-flash is to prevent glint from coming off your objective lens and giving away your position to the enemy.. A sunshade will only prevent glint at extreme angles since their is more surface area for light to enter. A Kill-flash greatly reduces the light gathering capabilities of an optic and need to be removed in low light. They are two very different things. Glint off an objective can be seen at up to 45deg from dead on.

[@firemedic7917]

Let's say whomever.

[@fabioguardiola7855]

i have to say i am a very smart guy but you sir have out witted me on this one!

[@RobWhittlestone]

Non è vero, Fabio! Vorrei guardare videos fai da te! Saluti, Rob

[@alecingram4669]

Does the honeycomb filter o rust the vision though the scope?

[@RobWhittlestone]

I think everyone would say yes, it does obstruct a little - it seems to reduce the contrast, from the comments I have read. All the best, Rob

[@xpeterman3423]

hahahaha at 0:37 5:53 and 15:00. But definatly a good idea worth trying. Gets a like from me

[@xpeterman3423]

nevermind my timing is all off by a lot. but 0:37 was funny

[@RobWhittlestone]

Hahaha yes I see what you mean! Thanks for watching! All the best, Rob

[@glmoren]

Clever solution. Congratulations

[@RobWhittlestone]

Thanks! Glad you like it! All the best, Rob

[@royalwulff1]

Great job

[@dartagnanv8der613]

BRAVO!!! Thank you for sharing!

[@RobWhittlestone]

+D'artagnan V8der You're welcome! All the best, Rob

[@calhepburn9738]

What size was the straws ..3 mm ?

[@RobWhittlestone]

Hi Cal - I bought smaller (thinner) and larger (thicker) ones and took the larger ones, because of my reasoning below "I think that the smaller the straw, the more straws I would need and the more light will be blocked, because each straw has a finite thickness." My guess about 5 or 6mm. Between 12:37 and 12:41 I show them in the sunshade. The sunshade is 56mm in diameter - so if you imagine 11 straws perfectly round -across the center then they will be 5mm straws. I hope this helps! Best regards, Rob

[@mossyoak404]

Excellent video sir !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

[@RobWhittlestone]

mossyoak404 Thank you, sir! It's great encouragement to receive comments like yours! All the best, Rob

[@huntingsgr8]

Great video, you deserve far more subscribers.

[@RobWhittlestone]

You are very kind, Sir! All the best, Rob

[@ZethAkadi]

Wow! That was most ingenious!

[@RobWhittlestone]

Zeth Akadi Thanks! All the best, Rob

[@anthonychavez3742]

Thanks for sharing.

[@RobWhittlestone]

And thank you for watching and commenting! All the best, Rob

[@ОлегНечаев-х2р]

Я Русский...Кто сможет объяснить что на видео?Я просто не понимаю :-\

[@RobWhittlestone]

Can anyone help Oner and translate this to Russian?

[@ОлегНечаев-х2р]

RobWhittlestone No((

[@RobWhittlestone]

Олег Нечаев UUups! Oleg - sorry! And translation to Ukrainian.

[@Giove83]

RobWhittlestone what a great idea i take my hat off to you :-) i have a sun shade but id going to give this ago tomorrow for my other two rifles, i also have an mtc taipan with the built in sun shade so would you just reccomend doing it just the same with that scope because the shade doesn't come off. thanks marco

[@RobWhittlestone]

Hi Marco Let me know how you get on: make a little video to show everybody! All the best Rob

[@teampenn2007]

Very smart.

[@RobWhittlestone]

You're very kind sir! A little flattery goes a long way :-)

[@stevenmeans6873]

so how do you put.it on a flash

[@RobWhittlestone]

Hi Steven - it's to suppress reflections (flash) from the glass of the telescopic sight lens which might alert the prey (or enemy). Thanks for viewing and commenting! All the best, Rob

[@stevenmeans6873]

Ok

[@jakubfiala637]

awsome

[@RobWhittlestone]

Thanks, man!

[@calhepburn9738]

Thanks ..thats a great bit of work

[@RobWhittlestone]

Thanks Cal! I had the idea for ages but just couldn't find black straws anywhere. I even considered buying them from bars but they would have charged me ridiculous prices. So I waited and found them (both sizes) in a cut-price store. All the best, Rob

[@calhepburn9738]

I have just tried ebay largest i can find is 4.5 .mm ....cheers

[@whomagoose6897]

Pure creative genius!

[@RobWhittlestone]

Many thanks! I'll add that to my CV! All the best, Rob

[@putuedysaputra2882]

genius!👍 idea

[@RobWhittlestone]

Thank you! All compliments gratefully received! 8-D Best regards, Rob

[@zanco92]

Gynius😀

[@RobWhittlestone]

Thank you! It was on my mind for weeks, I just had to solve it!