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[K3} Help, hex key for split knob

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ab2tc

[K3} Help, hex key for split knob

Hi all,

My RF gain knob finally did the inevitable, it split and fell off. I had seen the crack and expected this so I have a full set of concentric knobs on hand supplied free by Elecraft. But they did not supply a hex key and I don't have one that is small enough! My smallest metric one is 1.5mm and is too big. My smallest inch one is 5/64" which is close to 2mm and of course way too big. What is the size required and how do I go about acquiring it?

AB2TC - Knut

John_N1JM

Re: [K3} Help, hex key for split knob

If yours was a kit, you should of got one with it. However, I suspect you could get one from Elecraft. The small knobs use a .050" and the large knobs take 5/64" allen wrench.

ab2tc

Re: [K3} Help, hex key for split knob

Hi all,

I guess I"ll be heading out to the hardware store for a 0.050" or 1.27mm allen wrench tomorrow. My radio was a kit originally, but I bought it 2nd hand from the builder and may not have recieved the allen key.

AB2TC - Knut

N1JM wrote

If yours was a kit, you should of got one with it. However, I suspect you could get one from Elecraft. The small knobs use a .050" and the large knobs take 5/64" allen wrench.

Mike Reublin

Re: [K3} Help, hex key for split knob

If you can't find it at the hardware boutique, if there's a hobby shop
close, try that. I'd take the knob with me.

73,
Mike NF4L
ab2tc wrote:

> Hi all,
>
> I guess I"ll be heading out to the hardware store for a 0.050" or 1.27mm
> allen wrench tomorrow. My radio was a kit originally, but I bought it 2nd
> hand from the builder and may not have recieved the allen key.
>
> AB2TC - Knut
>
>
> N1JM wrote:
>
>> If yours was a kit, you should of got one with it. However, I suspect you
>> could get one from Elecraft. The small knobs use a .050" and the large
>> knobs take 5/64" allen wrench.
>>
>>
>
>

vk3dbd

Re: [K3} Help, hex key for split knob

I cannot imagine it would be hard to buy imperial measure Allen keys in USA
!
Even in VK land where "standards" of measure are very dubious. (officially
all metric) Our signposts in Kilometres, goods sold by the Kilogram,
Timber by the metre, - but they still talk about 4 x 2's and 6 x 8 ft
sheets of chipboard.....
Now, go in the ironmongers for nuts and bolts and the odds are you will find
them with BSW threads, a size now very difficult to get in England where
they originated!
I wonder why Elecraft used "inch" measure Allen screws?? when all the
other threads in the K3 are metric.- Perhaps they had similar problems!

73 to all from David VK3DBD

On Sat, May 8, 2010 at 10:35 PM, Mike <[hidden email]> wrote:

> If you can't find it at the hardware boutique, if there's a hobby shop
> close, try that. I'd take the knob with me.
>
> 73,
> Mike NF4L
> ab2tc wrote:
> > Hi all,
> >
> > I guess I"ll be heading out to the hardware store for a 0.050" or 1.27mm
> > allen wrench tomorrow. My radio was a kit originally, but I bought it 2nd
> > hand from the builder and may not have recieved the allen key.
> >
> > AB2TC - Knut
> >
> >
> > N1JM wrote:
> >
> >> If yours was a kit, you should of got one with it. However, I suspect
> you
> >> could get one from Elecraft. The small knobs use a .050" and the large
> >> knobs take 5/64" allen wrench.
> >>
> >>
> >
> >
>
>
> ______________________________________________________________
> Elecraft mailing list
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N3XX

Re: [K3} Help, hex key for split knob

Hi to all,

I just completed assembly of K3 #4175 a couple of weeks ago. When
installing the knobs I had a problem with both sizes of allen wrench
provided in the kit. For both size knobs, they would slip inside of the
allen screw as it started to get tight. I don't know what the actual size
should be, but ended up going into the box of allen wrenches I have saved
over the years and using sizes that fit better, allowing me to tighten the
screws. Sorry, I don't have the actual sizes needed, since I just found
what fit better and put them back into the box after I was finished. I
don't think there was actually any marking I could see anyway.

73,
Tim - N3XX

----- Original Message -----
From: "David Dunn" <[hidden email]>
To: "[hidden email]" <[hidden email]>
Sent: Sunday, May 09, 2010 4:47 AM
Subject: Re: [Elecraft] [K3} Help, hex key for split knob

>I cannot imagine it would be hard to buy imperial measure Allen keys in USA
> !
> Even in VK land where "standards" of measure are very dubious. (officially
> all metric) Our signposts in Kilometres, goods sold by the Kilogram,
> Timber by the metre, - but they still talk about 4 x 2's and 6 x 8 ft
> sheets of chipboard.....
> Now, go in the ironmongers for nuts and bolts and the odds are you will
> find
> them with BSW threads, a size now very difficult to get in England
> where
> they originated!
> I wonder why Elecraft used "inch" measure Allen screws?? when all the
> other threads in the K3 are metric.- Perhaps they had similar problems!
>
> 73 to all from David VK3DBD
>
> On Sat, May 8, 2010 at 10:35 PM, Mike <[hidden email]> wrote:
>
>> If you can't find it at the hardware boutique, if there's a hobby shop
>> close, try that. I'd take the knob with me.
>>
>> 73,
>> Mike NF4L
>> ab2tc wrote:
>> > Hi all,
>> >
>> > I guess I"ll be heading out to the hardware store for a 0.050" or
>> > 1.27mm
>> > allen wrench tomorrow. My radio was a kit originally, but I bought it
>> > 2nd
>> > hand from the builder and may not have recieved the allen key.
>> >
>> > AB2TC - Knut
>> >
>> >
>> > N1JM wrote:
>> >
>> >> If yours was a kit, you should of got one with it. However, I suspect
>> you
>> >> could get one from Elecraft. The small knobs use a .050" and the large
>> >> knobs take 5/64" allen wrench.
>> >>
>> >>
>> >
>> >
>>
>>
>> ______________________________________________________________
>> Elecraft mailing list
>> Home: http://mailman.qth.net/mailman/listinfo/elecraft
>> Help: http://mailman.qth.net/mmfaq.htm
>> Post: mailto:[hidden email]
>>
>> This list hosted by: http://www.qsl.net
>> Please help support this email list: http://www.qsl.net/donate.html
>>
> ______________________________________________________________
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Don Wilhelm-4

Re: [K3} Help, hex key for split knob

In reply to this post by vk3dbd

David Dunn wrote:
> I wonder why Elecraft used "inch" measure Allen screws?? when all the
> other threads in the K3 are metric.- Perhaps they had similar problems!
>
>
I am not certain why you think the other threads are metric in the K3 -
most of the screws are 4-40 which are not a metric size.
The K3 threads are "All American" :-) as far as I know.

Son W3FPR

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Ken Kopp-3

Split knob question

In reply to this post by ab2tc

If someone has a split knob in hand, please look
closely at the tapped hole. Since there seem to
be so many knobs splitting, I'm wondering if the
manufacturer has inadvertently tapped the screw
holes with a taper tap and not with a bottom tap,
as should be the case.

There are three degrees of tap taper in common use.
The bottom tap is straight and obviously produces
straight threads, but it's not as easy to start straight.

A set screw screwed into a hole threaded with a taper
tap would force the knob apart and might be the cause
of the splitting.

73! Ken Kopp - K0PP
[hidden email]

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Re: Split knob question

I have had numerous knobs split. None of them split while I was moving the set screw or even shortly thereafter. Most split after months of use and with no specific event happening other than moving the gain setting. The last set of knobs received about 5 or 6 months ago and supposedly with a new formula for the plastic are still hanging in there but I am still keeping the old knob from a defunct CB talkie so I at least have an audio gain. I am convinced that the problem is/was in the plastic mix and that Elecraft has done what is in their power short of buying a more expensive aluminum knob set.
Willis 'Cookie' Cooke
K5EWJ

________________________________
From: Ken Kopp <[hidden email]>
To: [hidden email]
Sent: Sun, May 9, 2010 1:18:46 PM
Subject: [Elecraft] Split knob question

If someone has a split knob in hand, please look
closely at the tapped hole. Since there seem to
be so many knobs splitting, I'm wondering if the
manufacturer has inadvertently tapped the screw
holes with a taper tap and not with a bottom tap,
as should be the case.

There are three degrees of tap taper in common use.
The bottom tap is straight and obviously produces
straight threads, but it's not as easy to start straight.

A set screw screwed into a hole threaded with a taper
tap would force the knob apart and might be the cause
of the splitting.

73! Ken Kopp - K0PP
[hidden email]

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Ken Kopp-3

Re: Split knob question

Hi Cookie, others

Apparently the matter of the splitting knobs has been dealt
with by some reformulation of the plastic "mix". Time will
tell if the "new" version of the knobs prove satisfactory.

73! Ken Kopp - K0PP
[hidden email]

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John Harper AE5X

Re: Split knob question

In reply to this post by Ken Kopp-3

No, it isn't.

My recent K3 (#4xxx) had two knobs (AF/RF gain) split as described - after
normal use some time after installation. This was in April. An email to
Elecraft produced two new knobs, one of which has since cracked despite my
extremely careful and gentle installation of them.

John Harper AE5X

>Hi Cookie, others
>
>Time will
>tell if the "new" version of the knobs prove satisfactory.
>
>73! Ken Kopp - K0PP

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Mike Reublin

Re: Split knob question

I like the taper tapped threads theory. It would be a nice experiment
for someone with a set of taps to check a knob. I wonder if one of the
split ones could be super-glued together to check.
Who's got the tools?

73, Mike NF4L

John Harper wrote:

> No, it isn't.
>
> My recent K3 (#4xxx) had two knobs (AF/RF gain) split as described - after
> normal use some time after installation. This was in April. An email to
> Elecraft produced two new knobs, one of which has since cracked despite my
> extremely careful and gentle installation of them.
>
> John Harper AE5X
>
>
>
>
>> Hi Cookie, others
>>
>> Time will
>> tell if the "new" version of the knobs prove satisfactory.
>>
>> 73! Ken Kopp - K0PP
>>
>
>
>
>
>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
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>
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>
>

Jens Petersen-2

Re: Split knob question

In reply to this post by Ken Kopp-3

On Sun, 9 May 2010 18:18:46 -0000, you wrote:

>A set screw screwed into a hole threaded with a taper
>tap would force the knob apart and might be the cause
>of the splitting.

Thread looks fine here (#3238)
--
OV1A Jens

Drive the way you wish your children would.
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Re: Split knob question

In reply to this post by Mike Reublin

I have the tools and I have checked. The threads are not the problem. I have epoxied knobs back together and they work fine, but glueing them together for the check will tell you nothing because they always break at the tapped hole. I am hopeful that the new knobs have cured the problem, but it will take a year or more to tell. The way to check a new knob is to run the screw in and out in the hole. Run it in until it is visible in the hole, but not so far as to hit the opposite side. If you run into significant resistance without the screw protruding into the hole you may have a problem. I did not when I made the test, but I have lost three sets of knobs due to breakage.
Willis 'Cookie' Cooke
K5EWJ

________________________________
From: Mike <[hidden email]>
To: [hidden email]
Cc: [hidden email]
Sent: Sun, May 9, 2010 3:47:02 PM
Subject: Re: [Elecraft] Split knob question

I like the taper tapped threads theory. It would be a nice experiment
for someone with a set of taps to check a knob. I wonder if one of the
split ones could be super-glued together to check.
Who's got the tools?

73, Mike NF4L

John Harper wrote:

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Grant Youngman

Re: Split knob question

I don't understand. I know there was a problem, but 3 sets? That's a lot of cracked knobs. I'm still on my ORIGINAL set (from serial 2091), and have a set of the "new material" knobs just in case, but still haven't had anything crack.

Does make one wonder if it's bad luck, or a different definition of "how much torque is enough torque". Or karma :-)

Grant/NQ5T

On May 9, 2010, at 5:34 PM, WILLIS COOKE wrote:

> I did not when I made the test, but I have lost three sets of knobs due to breakage.
>
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Re: Split knob question

In reply to this post by Ken Kopp-3

Gary, you saw something that I did not see. Whatever the defect in the knob Elecraft will promptly send you a new knob or any other part that may be defective. Certainly, no one should try to use a knob that takes appreciable force to tighten the set screw enough to see it in the hole. Just don't screw it in so far that it hits the other side and then apply force. That will break it for sure.

I have probably had as many broken knobs as anyone. I have never been disappointed in Elecraft's response when I asked for help!
Willis 'Cookie' Cooke
K5EWJ

________________________________
From: Gary Hvizdak <[hidden email]>
To: [hidden email]
Sent: Sun, May 9, 2010 8:11:43 PM
Subject: RE: [Elecraft] Split knob question

Hi Willis,

When #2724 arrived a year ago one of the set screws in one of the smaller knobs was so tight that it would only turn a small fraction of a turn when applying all of the force I could muster. I spent about 15 minutes running the set screw in and out with the hope of improving the threads. However, the knob still fractured probably because I had no way of knowing when the set screw was tight.

73,
Gary KI4GGX

________________________________

WILLIS COOKE wrcooke at yahoo.com
Sun May 9 18:34:41 EDT 2010

I have the tools and I have checked. The threads are not the problem. I have epoxied knobs back together and they work fine, but glueing them together for the check will tell you nothing because they always break at the tapped hole. I am hopeful that the new knobs have cured the problem, but it will take a year or more to tell. The way to check a new knob is to run the screw in and out in the hole. Run it in until it is visible in the hole, but not so far as to hit the opposite side. If you run into significant resistance without the screw protruding into the hole you may have a problem. I did not when I made the test, but I have lost three sets of knobs due to breakage.
Willis 'Cookie' Cooke
K5EWJ

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Jack Brabham KZ5A

Re: [K3} Help, hex key for split knob

In reply to this post by N3XX

Tim,

I had a similar experience assembling #4169 a few weeks ago. Unfortunately
my stack of assorted allen wrenches didn't include any that small.

My work around was to grind off the "stripped" portion of the cheesy allen
wrench each time it stripped.

It only took about two hours and several wrench grindings to mount the two
split knobs, which was really the only PITA encountered during the assembly.
The allen wrench was much smaller when I finished.

I suspect that a plain old slotted head screw would be more practical in
this application due to being able to apply torque over the screw's full
diameter.

73 Jack KZ5A

-----Original Message-----
From: [hidden email]
[mailto:[hidden email]] On Behalf Of N3XX
Sent: Sunday, May 09, 2010 8:45 AM
To: [hidden email]
Subject: Re: [Elecraft] [K3} Help, hex key for split knob

Hi to all,

I just completed assembly of K3 #4175 a couple of weeks ago. When
installing the knobs I had a problem with both sizes of allen wrench
provided in the kit. For both size knobs, they would slip inside of the
allen screw as it started to get tight. I don't know what the actual size
should be, but ended up going into the box of allen wrenches I have saved
over the years and using sizes that fit better, allowing me to tighten the
screws. Sorry, I don't have the actual sizes needed, since I just found
what fit better and put them back into the box after I was finished. I
don't think there was actually any marking I could see anyway.

73,
Tim - N3XX

----- Original Message -----
From: "David Dunn" <[hidden email]>
To: "[hidden email]" <[hidden email]>
Sent: Sunday, May 09, 2010 4:47 AM
Subject: Re: [Elecraft] [K3} Help, hex key for split knob

David Christ

Re: [K3} Help, hex key for split knob

My experiences are different. For small knobs you need to use high
quality wrenches. Those .050 do work if you have a good one. It's
amazing how much twist you can put in a high quality Allen wrench
while trying to deal with a stubborn screw. The next thing is to
make sure that you have them inserted all the way into the set screw.
That sometimes takes a bit of wiggling and pushing. Unfortunately,
there is the possibility of a damaged screw if it wasn't done right
before.

As an old-timer I dealt with many a slotted set screw. Nothing but
headaches. Good small bladed screwdrivers are much harder to find
than good small Allen wrenches. My favorite is the Bristol (splined)
design. http://www.bristolwrench.com/ Collins used them a lot.
Every now and then I think about replacing all my radio setscrews
with Bristol style but have not yet found a reasonable source for
them.

David K0LUM

At 1:25 PM -0500 5/11/10, Jack Brabham wrote:

>Tim,
>
>I had a similar experience assembling #4169 a few weeks ago. Unfortunately
>my stack of assorted allen wrenches didn't include any that small.
>
>My work around was to grind off the "stripped" portion of the cheesy allen
>wrench each time it stripped.
>
>It only took about two hours and several wrench grindings to mount the two
>split knobs, which was really the only PITA encountered during the assembly.
>The allen wrench was much smaller when I finished.
>
>I suspect that a plain old slotted head screw would be more practical in
>this application due to being able to apply torque over the screw's full
>diameter.
>
>73 Jack KZ5A

--
Education should be an accumulation of understanding, not just an
accumulation of facts.
Dr. David M. Pozar
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Don Wilhelm-4

Re: [K3} Help, hex key for split knob

In reply to this post by Jack Brabham KZ5A

Jack,

If you stripped out the allen wrench, you were applying more force than
is necessary, and excessive force may be the reason some of the newer
knobs are cracking (that is just a guess).

73,
Don W3FPR

Jack Brabham wrote:
> Tim,
>
> I had a similar experience assembling #4169 a few weeks ago. Unfortunately
> my stack of assorted allen wrenches didn't include any that small.
>
> My work around was to grind off the "stripped" portion of the cheesy allen
> wrench each time it stripped.
>
>
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W8JI

Re: [K3} Help, hex key for split knob

Knowing the problem we had on assembly lines with small
screws........... :-)

73 Tom
----- Original Message -----
From: "Don Wilhelm" <[hidden email]>
To: "Jack Brabham" <[hidden email]>
Cc: "'[hidden email]'" <[hidden email]>
Sent: Tuesday, May 11, 2010 6:38 PM
Subject: Re: [Elecraft] [K3} Help, hex key for split knob

> Jack,
>
> If you stripped out the allen wrench, you were applying
> more force than
> is necessary, and excessive force may be the reason some
> of the newer
> knobs are cracking (that is just a guess).
>
> 73,
> Don W3FPR
>
> Jack Brabham wrote:
>> Tim,
>>
>> I had a similar experience assembling #4169 a few weeks
>> ago. Unfortunately
>> my stack of assorted allen wrenches didn't include any
>> that small.
>>
>> My work around was to grind off the "stripped" portion of
>> the cheesy allen
>> wrench each time it stripped.
>>
>>
> ______________________________________________________________
> Elecraft mailing list
> Home: http://mailman.qth.net/mailman/listinfo/elecraft
> Help: http://mailman.qth.net/mmfaq.htm
> Post: mailto:[hidden email]
>
> This list hosted by: http://www.qsl.net
> Please help support this email list:
> http://www.qsl.net/donate.html