Loose chassis nut (hank bush) fix

[Dr.HI-TONE]

If you see a lot of Hylights or just get unlucky with your first, you may come across one with a loose chassis (hank bush) nut.

I just got one that was completely pulled out of the chassis!

Here is one way to fix it.



Use a hardened piece of steel and two small C clamps to support the loose hank bush.




Using a ball pien hammer, gently work the edges of the hank bush into the surrounding steel of the chassis.




once finished the hank bush should be firmly secured.

Good Luck and Happy HIWATTing!

[OldSchoolDave]

Cool info!

I learned two things today:

1) What a "hank bush" is

-and-

2) Dr.Hiwatt uses Tool Shop tools (a new endorsement deal? )

Dave

[Dr.HI-TONE]

I came home from work on a mission.
I had already finished fixing it, when I realized that I should have taken pics in case it might help others.
Darcy made fun of the tool shop tags too!

[marwatt]

where to buy those nuts??

[mhuss]

In the U.S. they are called press-fit nuts or sometimes PEM nuts (after the original mfr.) Any place that sells lots of machine-screw type hardware should have them (e.g., McMaster-Carr)

--mark

[Dr.HI-TONE]

I think the only tricky thing would be finding them in the #2 Imperial British thread to match the others. ????

I haven't looked for them.........

[buster]

Hi.
Here's a company selling 2BA hank bush's in the U.K.

http://www.rivetwise.co.uk/productrange/hankbushhex.htm

OR

http://www.rivetwise.co.uk/productrange ... hround.htm

[Dr.HI-TONE]

Thanks Buster!

[mhuss]

Hmm, that page only lists Metric sizes, but does mention BA in the 'thread forms' box.

Dr., isn't the US 8-32 thread very close in size to 2BA?

Anyone, is there an equivalent M# thread that is very close?

---mark

[Dr.HI-TONE]

10-32 is the closest.
I don't know about the metric threads????

[xsubs]

The metric size closest is M5 x .08, but that's not a perfect fit either. Neither that nor the 10-32 bolt would thread all the way in on my chassis. They'd go in a few turns, then jam.
One of my older 103's was missing two original bolts, so I tapped all four out to 10-32. The tap barely touched the threads at all, and went through easily. It's that close, but there is a difference. I couldn't find the British thread bolts anywhere here on the East Coast of the US. I'm sure I could have in Ireland (I'm there often), but didn't have the patience! I'm not worried about "collector value" as my Hiwatts will be buried with me!

[buster]

The metric size closest is M5 x .08, but that's not a perfect fit either. Neither that nor the 10-32 bolt would thread all the way in on my chassis. They'd go in a few turns, then jam.
One of my older 103's was missing two original bolts, so I tapped all four out to 10-32. The tap barely touched the threads at all, and went through easily. It's that close, but there is a difference. I couldn't find the British thread bolts anywhere here on the East Coast of the US. I'm sure I could have in Ireland (I'm there often), but didn't have the patience! I'm not worried about "collector value" as my Hiwatts will be buried with me!

Hi.
In order,smallest first. 2BA Threads per inch = 31.25 Tapping drill size is 4MM or 0.1575"
Then comes 10/32 TPI = 32 tapping drill size is #21 or 0.1590"
Then it's M5 tapping drill size is 4.20MM or 0.1654".

The reason the screw jammed was the slightly different TPI.
So indeed,not a lot in it.