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Source for 1.5mm thumb set screws?

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#1 Ricky

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Posted 05 February 2013 - 03:27 PM

Hi All,
Im looking to replace the set screws that allow one to adjust the polar alignment reticule on the Sirius Heq5 mount with equivalent thumb screws instead. Ive found out that the screws are 1.5mm...is that pitch? Im a newbie on screw specs. Does someone have info. on this and/or know where to find such replacement screws? :bow:

#2 don clement

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Posted 05 February 2013 - 03:38 PM

This should help. http://www.wisc-onli...802/mlt5802.htm

Don Clement

#3 Pinbout

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Posted 05 February 2013 - 03:56 PM

I used socket head allen caps screws from Home Depot, the head is big enough to grab with my fingers so I didn't press fit a knob on it.

#4 Ricky

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Posted 05 February 2013 - 04:06 PM

@Don...thanks for the link!

@Danny...did u do this replacement on your Sirius mount? If so, could you link the specific item at depot? Thanks much!

#5 Pinbout

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Posted 05 February 2013 - 04:20 PM

a cg5, it had a standar metric thread just took the set screw in and matched the thread and body dia.

scopestuff sell replacements for $16

#6 Ricky

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Posted 05 February 2013 - 04:23 PM

Thanks Danny! Ill check depot out.

#7 Geo.

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Posted 06 February 2013 - 09:55 AM

Doubt they're 1.5mm. Possibly 1.6, but I'd think 2.5 or 3 are more likely. At these sizes there are no thread pitch options. Find someone with a tap set to get a sure match. A good Ace will have a selection of metric fastners. I go to Richard Russo's hometown for the best selection in my area. Look for an ACE in an industrial area.

#8 Gordon Rayner

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Posted 06 February 2013 - 07:25 PM

Shear-Loc have press-on heads for some metric size socket capscrews . www.shear-loc.com 1-800-775-5668

They have a competitor in Flippin, Arkansas

www.microplastics.com

You could drill and tap some Delrin, nylon, PVC, aluminum, acrylic, Lexan, square pieces, and then lock with a nut, if necessary.

For thumbnuts, I have pressed square Delrin onto steel nuts. Drill the hole ( shallow, not a through-hole) of a size which just clears the sides of a hex nut. The hex corners cut into the Delrin, to lock the nut. Chamfering the edge of the hole makes entry smoother.

A thru hole to clear the screw body can be made before or after the nut is installed. If desired, make that hole the tap size, and start the tap in the threads of the installed nut. A tightly fitted nut will not usually tend to be pushed out during the beginning of tapping of the plastic . Or, clamp the nut with a plate or wood block with hole, to keep the nut from being screwed upward out of its hole during the start of tapping.

#9 Ricky

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Posted 06 February 2013 - 07:35 PM

Thanks for all of the suggestions!

#10 don clement

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Posted 06 February 2013 - 09:03 PM

Shear-Loc have press-on heads for some metric size socket capscrews . www.shear-loc.com 1-800-775-5668


Plus 1 on Shear-Loc press-on thumbscrews. I have had a Shear-Loc press-on assortment set (size #4 to 5/16) for over 30 years and has passed the test of time. The nice thing is that Shear-Loc works on all types of SCHCs including nylon SHCSs that work as a non-marring set screw. Also if the metric size is close in diameter and pitch they may be interchangeable. For example an inch size screw UNF 10-32 fits a threaded metric M5-0.8 screw hole pretty well since the OD of the #10 screw is 0.190" and the OD of an M5 screw is 0.197" also the 0.8mm pitch is very close to 32 threads per inch. A quick pass with a 10-32 tap will fix any discontinuity.

Don Clement

#11 Gordon Rayner

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Posted 06 February 2013 - 09:23 PM

I used 10-32 in the several M5-0.8 holes for bearing attachment on the Fuji 25 x 150 binocular body , first model (with trunnions), to install a a headrest support plate over the bearing flanges. There was never any problem, on many specimens, some of which are still in service.

This was because stainless socket cap screws M5-0.8 , of the required length, were not available ,or special order import $$$.

Such a substitution would not be appropriate for highly stressed automotive or aircraft application.

#12 don clement

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Posted 06 February 2013 - 09:29 PM

Such a substitution would not be appropriate for highly stressed automotive or aircraft application.


Yep. Don't intend to drive or fly an import telescope mount. ;-)

Don


“A song of great social and poetical import."
http://www.youtube.c...h?v=i-4AheUl6ls

Although in the original ATM book series there is mention of a TN that was killed when his under built mount collapsed on him.



#13 Pinbout

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Posted 07 February 2013 - 12:23 AM

“A song of great social and poetical import."
http://www.youtube.c...h?v=i-4AheUl6ls



I'd rather reference Husker Du - Wheels

[didn't link the youtube because of content.]






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