[Milsurplus] [ARC5] Penetrating oil test - Youtube

[Michael Hanz]

I completely agree, Mike.  My only hesitancy with the method, which I 
have used as well, is that the thermal mass of the tiny screwdriver 
blade, or Allen or Bristow wrench, cools _very_ quickly and requires 
multiple heat application in some cases. It has worked for me quite a 
few times, too, but not always.  Getting the hot tool into the small 
hole in the plastic knob with pliers isn't always as easy as it appears 
in theory.  A few of my knobs have some interesting melted divots where 
I missed in my haste to plug it in...😁
- Mike

On 4/24/2023 9:53 AM, Mike Feher wrote:
>
> Hi Mike & Group –
>
> I bought one of those, but never assembled it. Regardless, and maybe 
> someone has already mentioned it, is that on tough set-screws, usually 
> with Loctite or equivalent, I also found heat works best. I heat up 
> the tool that matched the screw, like Allen or whatever, and then use 
> the hot tool to instantly remove the screw. Has not failed me yet. 
> This way there is no heat applied anywhere else but the screw. The 
> tool has to be pretty hot, but not red, HI. Insert quickly and remove 
> offending screw. I also use a pair of applicable pliers to hold the 
> tool as it is too hot to hold by hand. 73 – Mike
>
> Mike B. Feher, N4FS
>
> 89 Arnold Blvd.
>
> Howell NJ 07731
>
> 848-245-9115
>
> *From:* arc5-bounces at mailman.qth.net <arc5-bounces at mailman.qth.net> 
> *On Behalf Of *Michael Hanz
> *Sent:* Monday, April 24, 2023 9:30 AM
> *To:* milsurplus at mailman.qth.net; ARC-5 List <Arc5 at mailman.qth.net>
> *Subject:* Re: [ARC5] [Milsurplus] Penetrating oil test - Youtube
>
> That's an excellent question, Wayne.  For years, I've followed these 
> kinds of tests closely for obvious reasons, and a lot of them are 
> subjective, with little in the way of scientifically designed boundary 
> conditions.  I have them back to over ten years ago, and probably 
> further, mostly in the vehicle maintenance and home shop machining 
> communities for obvious reasons.  Everyone swears by this solution or 
> that, but the sample set that any one of us radio guys personally has 
> is painfully low - how many of us do it on a regular basis with dozens 
> of samples?  And the real problem is that the size of the test threads 
> in these tests is almost always significantly larger than the 
> relatively small screws (like knob setscrews) that we have to address 
> most frequently.  Life ain't always linear.
>
> There is a later method that I've found useful, but it too involves 
> some limitations based on surrounding knobs/handles/etc., and that's 
> an induction heater.  The most difficult setscrews I have ever 
> encountered are on the glued-in screws in BC-191/375 transmitter 
> dials, and 10-15 seconds of heating works wonders without harming the 
> black bakelite knobs or paint at all.  If you can fit the coil around 
> the knob, it has always provided the cure - at least for me.  This has 
> been verified by the home shop machinist and vehicle communities as 
> well, but the difficulty is always the geometry of the frozen 
> screw/bolt with respect to surrounding structures.  The professional 
> models are a bit pricey and require a bevy of different coil shapes 
> and sizes in an attempt to cover the most situations.  I picked up one 
> for a few bucks on Amazon (search "low voltage induction heaters", if 
> interested)  but the quality of these Chinese products runs all over 
> the place, and you do need to wind more than one coil set for 
> different size radio knobs.  The good news is that these cheap drivers 
> generally work on 12-14vdc or 24-28vdc, voltages which may sound 
> familiar to most of you.
>
>
> As a result of its limitations, I would never call this solution the 
> answer to the "Ultimate Question of Life, the Universe, and 
> Everything".  That allegedly remains "42" according to _The 
> Hitchhikers Guide to the Galaxy_. YMMV. 😁
>
> Just another data point for consideration...as if we needed more.
>
>      73,
>  - Mike  KC4TOS
>
> On 4/24/2023 12:26 AM, hwhall at compuserve.com wrote:
>
>     What should we make of a chart that shows some products sometimes
>     make the required torque higher than if we used nothing at all??
>
>     Wayne
>
>     WB4OGM
>
>     -----Original Message-----
>     From: Hubert Miller <Kargo_cult at msn.com> <mailto:Kargo_cult at msn.com>
>     To: milsurplus at mailman.qth.net <milsurplus at mailman.qth.net>
>     <mailto:milsurplus at mailman.qth.net>; nwvrs at googlegroups. com
>     <nwvrs at googlegroups.com> <mailto:nwvrs at googlegroups.com>
>     Sent: Sun, Apr 23, 2023 9:19 pm
>
>     I have been puzzling, and kind of dreading, how best to approach
>     frozen setscrews in an old
>
>     radio. As if that isn't enough of a challenge, the frozen
>     setscrews ( grub screws ) are in positions
>
>     difficult to reach with any tool. What fun that will be. So this
>     little video was of some interest.
>
>     -Hue Miller
>