It is currently Sun Feb 28, 2021 12:28 pm

Click the link below to visit the site sponsor

The Ham Radio Shop




Post new topic Reply to topic  [ 12 posts ] 
 Jaybeam Yagi refit 
Contributor 2020

Joined: Thu Nov 27, 2008 10:47 pm
Posts: 645
Location: IO82ji Radnor
Feedback: 26 (100%)
Reply with quote
Post Jaybeam Yagi refit
I'm refitting, cleaning and replacing nuts bolts etc, a Jaybeam 2 metre yagi..
I've replaced all of the nuts and bolts holding elements etc with stainless.
Now I'm on the feedpoint, the original Jaybeam balun is in good condition but the aluminium machine screws holding it all together have twisted off..
Should I look for aluminium screws or would it be okay to use stainless.. ??

Evan


Sat Feb 01, 2014 9:21 am
Profile Send private message

 Jaybeam Yagi refit 
Advanced Member
User avatar

Joined: Sun Jul 22, 2007 8:58 pm
Posts: 401
Location: tamworth staffordshire
Feedback: 12 (100%)
Reply with quote
Post Re: Jaybeam Yagi refit
GW7UNV wrote:
I'm refitting, cleaning and replacing nuts bolts etc, a Jaybeam 2 metre yagi..
I've replaced all of the nuts and bolts holding elements etc with stainless.
Now I'm on the feedpoint, the original Jaybeam balun is in good condition but the aluminium machine screws holding it all together have twisted off..
Should I look for aluminium screws or would it be okay to use stainless.. ??

Evan



Hi I don`t think it will matter that much you should be able to use any screws to replace them just try it and see your see its will be ok


Sun Feb 02, 2014 9:25 am
Profile Send private message

 Jaybeam Yagi refit 
Contributor 2020

Joined: Thu Nov 27, 2008 10:47 pm
Posts: 645
Location: IO82ji Radnor
Feedback: 26 (100%)
Reply with quote
Post Re: Jaybeam Yagi refit
Thanks Phil..
I'll give it a go, I thought there was an electrical reason for the machine screws being aluminium rather than saving 2 grams of weight..
If it isn't tuned on 144.300 I'll source some aluminium ones..

Evan


Sun Feb 02, 2014 9:56 am
Profile Send private message

 Jaybeam Yagi refit 
Contributor 2020

Joined: Sun Aug 12, 2012 3:16 pm
Posts: 1303
Location: Dunfermline, IO86ib
Feedback: 14 (100%)
Reply with quote
Post Re: Jaybeam Yagi refit
Nice table here showing what metals you can mix and match to avoid corrosion

http://www.roymech.co.uk/Useful_Tables/ ... i_met.html


Sun Feb 02, 2014 10:37 am
Profile Send private message

 Jaybeam Yagi refit 
Online
Contributor 2020
User avatar

Joined: Sat May 23, 2009 1:46 pm
Posts: 22314
Location: Shropshire UK IO82TN
Feedback: 6 (100%)
Reply with quote
Post Re: Jaybeam Yagi refit
Thats a damn useful table! :good:

_________________
Dave G0BHD.
Been there and got the T shirt, sadly like the T shirt the memory of it has long since faded, gone rather tatty, and finally been consigned to the bin!


Sun Feb 02, 2014 10:50 am
Profile Send private message

 Jaybeam Yagi refit 
Contributor 2020

Joined: Sun Aug 12, 2012 3:16 pm
Posts: 1303
Location: Dunfermline, IO86ib
Feedback: 14 (100%)
Reply with quote
Post Re: Jaybeam Yagi refit
No problem Dave, I remembered seeing the idea mentioned on some kids science program about things rusting and corroding and thought I need to find out more, so there you go.


Sun Feb 02, 2014 10:58 am
Profile Send private message

 Jaybeam Yagi refit 
Online
Contributor 2020
User avatar

Joined: Sat May 23, 2009 1:46 pm
Posts: 22314
Location: Shropshire UK IO82TN
Feedback: 6 (100%)
Reply with quote
Post Re: Jaybeam Yagi refit
Of course it helps dispel the myth, some hold, that banging a stainless steel pin/bolt through any connection, minimises the risk of corrosion!
It only does in certain circumstances!
Fortunately for the OP, stainless steel and Aluminium, is one of the good combinations! :good:

_________________
Dave G0BHD.
Been there and got the T shirt, sadly like the T shirt the memory of it has long since faded, gone rather tatty, and finally been consigned to the bin!


Sun Feb 02, 2014 11:02 am
Profile Send private message

 Jaybeam Yagi refit 
Contributor 2020

Joined: Sun Aug 12, 2012 3:16 pm
Posts: 1303
Location: Dunfermline, IO86ib
Feedback: 14 (100%)
Reply with quote
Post Re: Jaybeam Yagi refit
And disspells the myth that science is a useful subject to study....


Sun Feb 02, 2014 11:04 am
Profile Send private message

 Jaybeam Yagi refit 
Contributor 2020

Joined: Thu Nov 27, 2008 10:47 pm
Posts: 645
Location: IO82ji Radnor
Feedback: 26 (100%)
Reply with quote
Post Re: Jaybeam Yagi refit
All of the other screws, holding the elements, were stainless with diecast zinc alloy wing nuts. All of these nuts failed to undo.
Seems a bit odd to put stainless screws throughout the rest of the antenna..

Evan


Sun Feb 02, 2014 11:17 am
Profile Send private message

 Jaybeam Yagi refit 
Advanced Member

Joined: Thu Jan 05, 2012 9:38 am
Posts: 2058
Location: Southwest Angus IO86LL
Feedback: 7 (100%)
Reply with quote
Post Re: Jaybeam Yagi refit
The diecast wing nuts were always a bad Idea you were lucky for them to last more than a couple of years it must have been a cost cutting idea that had them fitted even plated steel would have lasted longer

But not all stainless steel are good/bad it is the quality that matters try leaving a piece of stainless steel in water for a few days, if its poor quality the surface will start to discolour if poor quality.

_________________
Peter GM1CMF


Sun Feb 02, 2014 11:21 am
Profile Send private message WWW

 Jaybeam Yagi refit 
Contributor 2020

Joined: Thu Nov 27, 2008 10:47 pm
Posts: 645
Location: IO82ji Radnor
Feedback: 26 (100%)
Reply with quote
Post Re: Jaybeam Yagi refit
Thanks chaps for the replies..

I've ordered some aluminium alloy bolts for the job and going to use stainless flange nuts to make the feedpoint.. The old ones were rusty mild steel.

Thanks for the mix & match chart, I've just saved that.. :)

Evan


Mon Feb 03, 2014 9:49 am
Profile Send private message

 Jaybeam Yagi refit 
Intermediate Member

Joined: Mon Jan 07, 2013 9:58 pm
Posts: 59
Location: Lytham St Annes IO83LS
Feedback: 6 (100%)
Reply with quote
Post Re: Jaybeam Yagi refit
So, from the table, Cad plated steel screws are a good choice (except aluminium) for use with an aluminium antenna structure, or may be Bright Zinc Plate (BZP) steel screws as they are closer to copper or tin (solder tags) for making off to the feeder?

_________________
Steve
G0AIN

That looks interesting - I shall poke it with a stick...


Sun Feb 09, 2014 10:01 am
Profile Send private message
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 12 posts ] 


Who is online

Users browsing this forum: No registered users and 0 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Jump to:  
Powered by phpBB © phpBB Group.
Designed by Vjacheslav Trushkin for Free Forums/DivisionCore.