Cable-tie sighting device: IMPROVED! COLLAPSABLE! (1 Viewer)

[KorHaan]

Hello everyone,

About three years ago Kimmo Absetz and I presented instructions how to make a simple sighting device for an angled scope, from one simple cable-tie:


http://www.birdforum.net/showthread.php?t=99084


Only recently my fellow countryman Folkert de Boer came up with an improved version, based on the original idea:

A COLLAPSABLE cable-tie sighting device!


http://forum.waarneming.nl/smf/index.php/topic,132667.0.html


I have his kind permission to post his idea on this forum, and though the Dutch text will be lost on most users here, the pictures will amply show the working of this excellent gadget, I'm sure.

The fact that the sighting device is collapsable means, that it can be wrapped around the stay-on case of the scope without compromising the functionality, and it will not shift it's position when the scope is put in a bag or rucksack.

As soon as I learned about Folkerts idea, I made a series of instructional drawings in the same way I did on the original (one cable-tie ) thread, to make it easy for everyone who's interested, to make their own collapsable device.

See the attachments, for step-by-step instructions.


The calibration of the sighting is done in the same way as in the original one-tie drawings, given in the link above.

Have fun trying this!

Best regards,

Ronald Sinoo

 

[Kevin Purcell]

Excellent. Thanks for taking the effort to draw this up.

 

[KorHaan]

The solution Folkert came up with for angled scopes with an off-set eyepiece ( like for instance the Nikon ED 82) is as brilliant as his collapsable device:

http://forum.waarneming.nl/smf/index.php?action=dlattach;topic=132667.0;attach=363234;image

This way the sighting device can be used with an off-set eyepiece and is perfectly vertical.

Best regards,

Ronald

 

[KorHaan]

Thanks Kevin,

My pleasure.

If anyone has questions I'm more than willing to answer them!

Best regards,

Ronald

 

[Kevin Purcell]

Ronald: This goes back to a previous comment on another thread about Brett Richards on the BBC documentary "Twitchers". I recall he used a (silver) Zeiss 85FL scope for seawatching and noticed his "case" was wiretied into place which I thought a little odd. I don't think he was using an aiming device. Perhaps that's a step in the evolution of these pointers?

 

[fkdeboer]

the drawings look terrific, Ronald!
thanks for making them and spreading the word about collapsable Cable-tie sighting devices!

 

[kabsetz]

Thanks Folkert and Ronald!

This looks very clever, and I will try it to see if the accuracy remains as good as with the fixed one. We can hope that it further increases the popularity of this very effective aiming system.

Kimmo

 

[mayoayo]

Honestly,I tried this and couldnt accurately find my target,,couldnt find my target not accurately either...I am a moron,I admit it aforehand..but..I mean,,You need to make coincide two(fixed) points to create a perpendicular aiming trajectory..One is the Tie,what is the other one?..I use a red dot finder,and spots-ON a flying bird in one second ,with my eye already in place to switch from the finder to the eyepiece...I tried the tie ,hoping to get rid of the bulky finder,but couldnt make it work...

 

[John Russell]

Nicely drawn, Ronald, but it all looks a bit Heath Robinson, flimsy and correspondingly inaccurate.

Wouldn't it be better to have a sheet metal ring clamp at the objective end with a swivelling sight? Unfortunately, being a computer dyslexic I can't upload the idea :-(.

Also the solution of putting the sight on the prism housing for offset eyepieces (Nikon, Optolyth) would give a very short sight basis. I see no reason why not to leave the sight at the objective end and simply incline it to be in line with the eyepiece.

John

 

[KorHaan]

Thanks Folkert and Ronald!

This looks very clever, and I will try it to see if the accuracy remains as good as with the fixed one. We can hope that it further increases the popularity of this very effective aiming system.

Kimmo

Hi Kimmo!

Great you chimed in! I look forward to your test results.

B
Best regards,

Ronald

 

[KorHaan]

Honestly,I tried this and couldnt accurately find my target,,couldnt find my target not accurately either...I am a moron,I admit it aforehand..but..I mean,,You need to make coincide two(fixed) points to create a perpendicular aiming trajectory..One is the Tie,what is the other one?..I use a red dot finder,and spots-ON a flying bird in one second ,with my eye already in place to switch from the finder to the eyepiece...I tried the tie ,hoping to get rid of the bulky finder,but couldnt make it work...

The top of the tie is like the bead on a rifle, your eye looks just over the edge of the ocular. That's basically how it works, the "bead"is on the bird, and in the centre of the ocular at the same time.

Best regards,

Ronald

 

[KorHaan]

Nicely drawn, Ronald, but it all looks a bit Heath Robinson, flimsy and correspondingly inaccurate.

Wouldn't it be better to have a sheet metal ring clamp at the objective end with a swivelling sight? Unfortunately, being a computer dyslexic I can't upload the idea :-(.

Also the solution of putting the sight on the prism housing for offset eyepieces (Nikon, Optolyth) would give a very short sight basis. I see no reason why not to leave the sight at the objective end and simply incline it to be in line with the eyepiece.

John

Hi John,

As long as everyone can work out the flimsy drawings, I'm more than happy.
I haven't had complaints yet that the inaccuracy made it impossible to follow the instructions, maybe it's because of the simplicity of the drawings that everyone so far understands the principle.

The sight is always on the objective end of the scope, on a scope with an offset eyepiece also. The schematic that Folkert provided for offset-eyepiece scopes, shows the scope from the objective end, and the "wig" is a wedge that can be placed under the tie on the objective end, to make the sight stand perfectly vertical.
Without a wedge, the sight would be at a slant, but still useable.
The wedge can be foam or rubber, as long as it is solid enough to provide a platform around which the tie can be strapped to the scope. Hence the squarish impression

My bad for not explaining this earlier.

Best regards,

Ronald

 

[Kevin Purcell]

the centre of the ocular at the same time

The top center (the highest point on the ocular). This design only works for angled scopes.

The idea is you just look over the top of the ocular (as you would the back sight of a gun). Just tilt you head up from looking down into the ocular.

Nicely drawn, Ronald, but it all looks a bit Heath Robinson, flimsy and correspondingly inaccurate.

It's easy to recalibrate it in the field with one sighting. The only thing that can change is the rotation of the cable tie.

 

[KorHaan]

I seem to have misunderstood John Russells words, as he was referring to the sighting not the drawings. I'm embarassed, sorry, John!

Kevin,

You're absolutely right! It's not the bead in the centre of the ocular, I meant the bird in the centre of the ocular.

Best regards,

Ronald

BTW, who's Heath Robinson?

 

[Kevin Purcell]

BTW, who's Heath Robinson?

A cartoonist famous for his intricate contraptions.

http://en.wikipedia.org/wiki/W._Heath_Robinson

Similar to Rube Goldberg in the US

http://en.wikipedia.org/wiki/Rube_Goldberg_machine

This last URL has a lot of synonyms for other countries but not Netherlands.

This sight doesn't have enough parts to be really "Heath Robinson" or "Rube Goldberg".

 

[John Russell]

I seem to have misunderstood John Russells words, as he was referring to the sighting not the drawings.

Exactly, Ronald, your drawings are beyond criticism.

John

 

[chris butterworth]

Thanx for the tip. I normally use the " nipple " end of the press-stud that closes the front cover of my stay-on-case as a guide but - after many years - it has finally dropped off. This will make a cracking replacement.

Chris

 

[Jason Bugay Reyes]

Thanks a lot Ronald !

 

[sherlock]

I have had a go at fitting the sight at the eyepiece on my opticron mighty midget.

Although I have been unable so far to get it to fold forward I am really plesed with the results of a quick test through the window. Once set up for a session it sure does make things easier. Its only 12 - 32x magnificstion so keeping the sight at the eyepiece end might well be good enough.

If I think it can be improved I might well try a sight closer to the objective lens.

Then I will have a go with the ED82 and I guess with higher magnification it will need to be more accurate. :t:

Many thanks for the idea!

 

[Mike Penfold]

On a rainy late afternoon, it seemed a good time to figure out the scope sight on our angled Zeiss 65.

It took a couple of times to see that cable A can't be tightly closed as the diagram suggests, as it forms an elliptical shape which locks it on to cable B, preventing A from being rotated to a viewing position (at least with the cable ties I'm using).

It's difficult to get the stub of cable B into a completely horizontal position, causing cable A (when raised to its vertical position) to be slightly offset to the left. Doesn't seem to make much of a difference in actual use.

With eyeglasses, it's impossible to just move your eyes when alternating between the eyepiece and sight. With a dominant left eye, if I put the tip of my nose at 3:00 o'clock on the eyecup, sighting over the tip of the sight, and then rotate my head down and forward, it works.

Thanks.

Mike Penfold