Author Topic: Replacing undercut chrome barrels  (Read 28 times)

James Holt

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Re: Replacing undercut chrome barrels
« Reply #15 on: January 23, 2018, 02:30:08 AM »
Ok, it's nice to rant and rave about those lousy, stinking, horrible, annoying, lower-than-a-snake's-belly, irritating, useless, worthless and STOOOPID undercuts but I want solutions.

I do like the idea of making replacements where possible. Maybe like someone who already does tweaky stuff like Precise Parts and Scope Stuff. But that will take time and, importantly, the willingness to do.  I also like the idea of just saying to OEMs somehow in a loud, collective and effective voice to stop it or offer smoothie versions too.  But, again, that takes time and does not address the problem, and it IS a PROBLEM for already fielded hardware.

It seems for non or minimally tapered undercuts with a decent flat in the under cut, pin striping is a very attractive, easy and reversible solution.

The thorny one to me are those horrible tapered undercuts. They are complete trash and have completely eliminated the possibility of using some extremely desirable, so called high end eyepiece in my bino viewers. Has anyone an effective solution for those?

Jeff

Levi Cruse

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Re: Replacing undercut chrome barrels
« Reply #16 on: January 23, 2018, 12:19:24 PM »
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Has anyone an effective solution for those?

A lathe at home capable of metric threading, some tooling, and fresh stock is all it takes.

Derek Vail

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Re: Replacing undercut chrome barrels
« Reply #17 on: January 31, 2018, 05:00:46 AM »
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Has anyone an effective solution for those?

A lathe at home capable of metric threading, some tooling, and fresh stock is all it takes.
Sure! But I was thinking more of something that could be added to the current tapered eyepiece barrels.

Charles Marin

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Re: Replacing undercut chrome barrels
« Reply #18 on: January 31, 2018, 05:15:25 AM »
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I really like my Orion Expanse 15mm, but I HATE the undercut on the barrel. I run a Dob so my focuser is never pointed below horizontal and I like to keep the thumb screws just slightly loose so I can gently slip different eyepieces in and out; the undercut is nothing but a nuisance as it hangs on the screw every time and I have to stop and futz with the screw to get the EP out and put the next one in, etc. I tried swapping out the barrel with one of the smooth ones from a Plossl I have but the barrel threads on the Orion eyepiece seem really coarse and don't match the standard threading on my Plossls. Is there somewhere I can get replacement barrels for the Expanse that don't have the undercut?  I know some people just use tape or other materials to fill the undercut but I'm looking for a more robust solution...
Just remember if you use the 9mm and 6mm Expanse that you have barlowed lenses that are part of the undercut barrels.When i really get sick of screwing and unscrewing that d*** screw two or three pain in the neck turns each time I change to a different eyepiece because of the screwball idea of undercuts that someone dreamed up for people with GEM's and just ignored the rest of us with Dob's and other type scopes where the eyepiece can't possibly fall out, what I do is just leave the focuser screw loose. Since I am a deep sky observer I can't really tell the difference in what I see.Another pain in the neck is the screw to "secure" an eyepiece in a Barlow. I will just take this screw out, but I will secure the focuser screw holding the Barlow.Again, since almost all my observing is galaxies and other dso's, I honestly can't see any difference in image quality with focuser screws snug or loose.Jim, trying to replace them with smooth barrels sounds tricky. You might in the future look for older quality, smooth barrel eyepieces in the used market.Thanks a lot China!

raposttavers

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Re: Replacing undercut chrome barrels
« Reply #19 on: January 31, 2018, 11:37:41 AM »
Jim, is my suggestion in post 2 of this thread a reasonable solution for your particular setup?
A lower set screw wouldn't catch on your undercuts and you could still gently snug your eyepieces within the tube. You'd sacrifice the use of a compression ring, but so what? You could use nylon for your set screw if marring is a concern.

Stanley Elliott

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Re: Replacing undercut chrome barrels
« Reply #20 on: February 09, 2018, 11:04:17 AM »
My solution is to use Baader ClickLocks for all visual backs and eyepiece adapters and TV Binovues for two-eyed viewing.
The only time I now have the issue is with the N31T5 in the FTF 2015BRC-LW on my dob....