Filling eyepiece undercuts for Hyperion and Tak prism combo

[jadcx]

Hello

I was wondering of anyone has any neat and tidy ides for filling eyepiece undercuts?  Specifically, I have some Baaden Hyperions which are nice and all, but a little annoying in my Tak prism as the undercut means that the collar on the prism doesn't quite tighten.  And yes, I'm very happy with the Tak prism otherwise, so lets not do the whole Baader Zeiss/T2 prism discussion here  

One possibility is to slightly shorten the collar in the Tak but I'd rather not if there is a tidy way to 'fill in' the undercut section.

J

[John]

I've seen a sort of metal adhesive tape used for this purpose. This sort of thing:

https://www.ebay.co.uk/itm/Silver-Mirror-Tape-Self-Adhesive-Hoop-Tape-Lures-20mm-wide-x-10m-long/292264417158?hash=item440c511786:g:798AAOSw~ZBZw7au

[jadcx]

1 hour ago, John said:

I've seen a sort of metal adhesive tape used for this purpose. This sort of thing:

https://www.ebay.co.uk/itm/Silver-Mirror-Tape-Self-Adhesive-Hoop-Tape-Lures-20mm-wide-x-10m-long/292264417158?hash=item440c511786:g:798AAOSw~ZBZw7au

Thanks - I can that that could work. I had wondered about using PTFE tape but I think that would quickly get messy.

[Louis D]

Check out this CN'ers solution.  You'll want 1/4" or 6mm wide pinstripe tape.

[jadcx]

39 minutes ago, Louis D said:

Check out this CN'ers solution.  You'll want 1/4" or 6mm wide pinstripe tape.

Thanks - have you tried this or are your googling skills just better than mine?  😊

[Stu]

I just cut a piece of insulating tape to the right width and wrapped it into the undercut on my 24mm Panoptic. It took a small amount of experimenting with how many turns to use, but the Tak prism compressed it firmly into place and it now does not catch at all. It's been there for a year or two with no signs of budging so it seems a good cheap solution.

[Louis D]

49 minutes ago, jadcx said:

Thanks - have you tried this or are your googling skills just better than mine?  😊

I just remembered reading that thread and looked it up for your sake (along with a UK source).  While undercuts annoy me, I have yet to reach the point of feeling the necessity to fill them it.  I can only remember once when a focuser's brass compression band came out of its track and got wedged against the eyepiece as I lifted it out.  I was cussing pretty hard trying to get it to release.  I'd be most likely to fill them in on my binoviewer pairs where the undercuts lead to eyepiece tipping in the collets which causes insurmountable misalignment.

[jadcx]

Thanks guys - I think I’ll try the insulation tape first as I already have some

[Merlin66]

Yeah, those "safety" undercuts are the Devil's work!!!

I don't think the user - you and me - were ever consulted before the manufactures decided in our behalf that "all new product" would have them.

Give me the smooth sided versions anytime.

 

[Davey-T]

I have a roll of self adhesive PTFE tape I use to fill the annoying things.

Dave