Robert wrote:
> With the potential problems with galling with stainless u-bolts why not use
> galvanized? Just curious!
>
ROHN did. Of course even though they have to tell people repeatedly not
to drill out the bolt holes to get the bolts to fit and not to screw the
bolts into the holes using the threads to open them up. You still see
people, not just hams, drilling out those bolt holes when they are
supposed to use a taper pin punch to open out the hole so the bolt just
fits. Then they wonder why they find rust.
The different bolt materials like most every thing else are a group of
compromises. SS stands up well and comes in a wide variety of alloys.
There are hard, soft, and tough versions as well as magnetic and non
magnetic. It just doesn't get along well with it self unless properly
treated. I think you will find Galvanized does not come in grades due
to the heating of the galvanizing process. (I'm a bit hazy on this so
any one is welcome to chime in). The Galvanizing is a sacrificial metal
and works very well. The strongest and hardest bolts are the ones that
corrode/rust the easiest and require external coating (paint) that
weathers well.
It's kinda the case of "You pays you money and takes your choice".
73
Roger (K8RI)
> Bob W7KD
>
>
> ----- Original Message -----
> From: "Lyle Hornbaker" <lyle.hornbaker@verizon.net>
> To: "Tower and HF antenna construction topics." <towertalk@contesting.com>
> Sent: Tuesday, April 13, 2010 6:01 AM
> Subject: Re: [TowerTalk] dxengineering U-bolts froze??
>
>
>
>> Yep. Galling is the term for what you saw. It is most likely to happen in
>> stainless steel and really is a function of the material but there are
>> ways you can reduce the likelihood of galling. I actually haven't seen it
>> in fasteners but I was in the submarine service in the Navy and we had
>> stainless steel valves with caps that were prone to galling.
>>
>> The key is to make sure that you are careful during installation as you
>> usually start galling on the installation and only make it worse during
>> removal. Don't over torque. Use slower speeds (no high speed impact
>> wrenches!). ALWAYS use an anti-seize lubricant. If you continue to have
>> problems, choosing fasteners where the bolts and nuts are made of
>> different alloys can help. Here is a quick internet site that explains a
>> bit more. http://www.estainlesssteel.com/gallingofstainless.html
>>
>> 73
>> Lyle - KI4WKT
>>
>> From Lat 36.98135 N
>> Long -76.63769 W
>>
>>
>>
>>
>> ________________________________
>> From: "Dubovsky, George" <George.Dubovsky@andrew.com>
>> To: Tower and HF antenna construction topics. <towertalk@contesting.com>
>> Sent: Tue, April 13, 2010 8:45:56 AM
>> Subject: Re: [TowerTalk] dxengineering U-bolts froze??
>>
>> Bob,
>>
>> It's called "galling" and most stainless alloys are prone to it. It's just
>> like the parts weld together. The cure is to always lubricate stainless
>> fasteners during assembly. I carry a brush-top can of Never-Seez whenever
>> I'm doing tower work, but any light grease will work just fine.
>>
>> 73,
>>
>> geo - n4ua
>>
>> -----Original Message-----
>> From: towertalk-bounces@contesting.com
>> [mailto:towertalk-bounces@contesting.com] On Behalf Of Bob AD5VJ
>> Sent: Tuesday, April 13, 2010 8:38 AM
>> To: towertalk@contesting.com
>> Subject: [TowerTalk] dxengineering U-bolts froze??
>>
>> I like dxengineering parts; however, I installed my new th6dx this last
>> weekend with the help of the Azle Ham Club here locally. After taking down
>> my Hornet Tribander I was disassembling the Hornet from the mounting plate
>> that I bought from dxengineering.
>>
>> I bought it with the recommended stainless steel U-bolt clamps they sell
>> when I put the Hornet up. It was up less than a year on the tower. While I
>> was loosening a couple of the U-bolt from the mast, the nut holding a
>> couple
>> of the U-bolts became very hard to take off until I had to place the
>> assembly in a vice to get enough torque on my wrench to finally get the
>> nut
>> off along with using a spray lubricant.
>>
>> The threads are ruined on the nut and the U-bolt since it seemed to cross
>> thread as it came loose for no apparent reason.
>>
>> I would have hated to have been trying this on top of the tower hanging
>> from
>> a strap trying to get it apart.
>>
>> Has anyone else had a problem like this, I remember it wasn't hard to
>> tighten when I assembled it as it went on very easily, just taking it off
>> was very difficult.
>>
>> 73,
>> Bob AD5VJ
>>
>>
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk@contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk@contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>> _______________________________________________
>>
>>
>>
>> _______________________________________________
>> TowerTalk mailing list
>> TowerTalk@contesting.com
>> http://lists.contesting.com/mailman/listinfo/towertalk
>>
>
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
>
_______________________________________________
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
|