Model Engine Maker
Supporting => Engine Ancillaries => Topic started by: vcutajar on March 10, 2018, 05:25:37 PM
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As the topic subject implies, I need to find 2.5 x 30mm bolts. They must be hex head. I have spent the day searching for them but just can't find them. Ideally stainless steel but any other material will be good. As a last resort I may even consider near equivalent in imperial.
Help please.
Vince
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Hi Vince
7 BA is a very close size.
Reeves stock them
http://www.ajreeves.com/hexagon-head-boltsscrews.html
Cheers
Rich
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I think you will have a job finding much over 20mm long and they would be fully threaded hex head screws not bolts.
How many do you need? Sometimes for long bolts I thread the end of a rod and silver solder on a nut that way you can make bolts to whatever length you need without having to turn long slender shanks. Or can you use studs and nuts?
J
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Rich, I checked those 7BA bolts but they are not long enough.
Jason, I can work with fully threaded hex head screws as long as it is 2.5mm thread.
Can anybody tell me what's the closest equivalent in UNF or UNC?
Vince
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Hi Vince, as Jason mentioned, over 20 mm will be difficult.
https://www.screwsandmore.de/de/sortiment/schrauben-und-bolzen/innensechskant-schrauben/zylinderkopf-din-912/din-912-edelstahl-a4/din-912-a4-m2-5/din-912-a4-m2-5x30/1600/25-stueck-din-912-a4-m2-5x30
They have more in 2,5x30 but no hex head.
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3-48 UNC would be the closest at 2.51mm but #3 is not a preferred size so choice will be limited. Next down is 2-56UNC at 2.18mm.
EKP do 7BA at 1" long which is a bit better than Reeves but still leaves you short.
Longest M2.5 I have are 20mm from GHW.
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7BA x 30 and they are bolts
http://www.ba-bolts.co.uk/smallhex.html
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Those 7BA x 30 look ideal. Unfortunately they are one size smaller head and I need a regular size head. Looks like I have to make them myself.
Vince
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You could do worse than JasonBs' idea but loctite the nut on with a retaining grade of Loctite, this can be made to look like the head of a bolt, or with a thread showing through, a stud.
Ian S C
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I find that if a skim cut is taken after soldering the threaded nut on that the joint shows up far less than if you use loctite.
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I find it very enjoyable making my own fasteners :) They come in every size you need with the correct head size, chamfered if desired and thread free length :ThumbsUp: And they don't go rusty sitting in the drawer for a couple of decades waiting to be used ::).
Jo
(Cap head screws are another matter :-\ )
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Something tells me that I will not be enjoying making 120 of them.
Vince
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Something tells me that I will not be enjoying making 120 of them.
I know the feeling ::) having to make large batches was why I used to use engineering stud and nut humour to break up the monotony before a bunch of old prudes complained about it :disappointed:
Jo
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You must be nuts to think that, Jo. Everyone around here knows that your passion for well-formed studs is nothing more than an innocent admiration of skillfully used tools in the pursuit of the perfectly executed screw.
AS
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:lolb: