Tutorial: Recessing toroid bold head without expensive tools

[riggler]

I was home sick with pneumonia today, and was working on my SB4000. I came up with this idea for recessing the toroidal transformer mounting bolt. I hate having things sticking out of the case like that.

You'll need:

7/8" or 1" Socket.
7/16" Wrench.
7/16" Ratchet and Socket.

One 1/4-20 nylon bolt and washer. (Mount the transformer with these. My bolt was 2" long and I Dremeled off the extra when done.)

One 1/4-20 steel bolt, 2.5" long.***
One 1/4-20 steel nut.***
Three 2" diameter 1/4" fender washers.***
Three 9/16" diameter 1/4" washers.***

***These are all standard hardware-store sizes and should be easy to get.

Step 1:
Here are the parts you need.

Step 2:
OIL the tip of the bit and drill your center hole.

Step 3:
Place the three small washers on the long steel bolt like this. Oil the face of the washer that will be against the bolt head!

Step 4:
Pass the bolt through the hole. Make sure the hole is de-burred. That top washer needs to be flush with the bottom of the panel!

Step 5:
Thread on the nylon 1/4-20 nut to a position that will be about halfway into your socket when your large socket is placed over it. Trust me. If you don't have a big socket, you could use a piece of 1" pipe cut to about 2" long.

Step 6:
Showing the vertical position of the nylon nut in the socket, about halfway in.

Step 7:
Remove the socket, and wrap the nylon nut with tape (keeping the TOP flush) until the socket *just* slides over the tape. This will keep things centered for you.

Step 8:
Check the fit.

Step 9:
Put the socket back on. Now oil the top of the bolt thread and the steel nut. Place the big three fender washers on top of the socket, and hand tighten the nut.

Step 10:
It should look like this. Check to make sure you have a decent center alignment.

Step 11:
One hand holds the wrench, other hand turns the ratchet! Get the idea?

Step 12:
Go slow. Because you oiled everything, it should go nicely. This picture is after about three full revolutions if I recall.

Step 13:
STOP turning when you can't see the second small washer anymore! Okay, well maybe one little turn just to be safe ha ha...

The result:

Another angle:

 

[andrew_k]

Too cool  8)
Thanks for sharing!

 

[Ethan]

That's awesome Riggler!

The thought just occurred to me that the forum is filled with little tutorial gems like this.  We should really start organizing and categorizing this a la "instructable" style!
So many things to do, so little time...

 

[riggler]

I am going to be 110% honest and say that I love the Metas. I am still waiting for CJ to finish the AC theory beginners guide ;-)!! I think you are right, in that we lose a lot of information deep in threads. Sometimes the search works well, sometimes it's impossible. But I think we're still in very good shape. And things like the schematics database, now THAT is rad!

It takes so much time and effort to keep the organization clean. Props to the moderators!!

 

[riggler]

Another tip:

If you need nice stranded power cable for wiring up your project internals, cut the ends off and strip the jacket off of a standard PC IEC power cable. They can be had for free if you look! Most of the ones I have used have green, black, and white internal lead jacket covers.

 

[abechap024]

Dude!
Mad props. Thanks for sharing!

 

[rob_gould]

That's absolutely fantastic - I'll definitely be trying this on my next build.

I was actually asking about this on a different thread the other day, so great timing

Thank you.

 

[sahib]

Another tip:

If you need nice stranded power cable for wiring up your project internals, cut the ends off and strip the jacket off of a standard PC IEC power cable. They can be had for free if you look! Most of the ones I have used have green, black, and white internal lead jacket covers.

Let me add to this.

I often visit our local civic amenity centre, otherwise known as the dump, and regularly pick-up  audio equipment which is a source of all sorts of  hardware as well as the signal and power wires. My best finds included dj mixers in superb condition which gave me tons of jack connectors etc. and a Tascam 234 multitrack cassette deck.

 

[gemini86]

We have a recycling yard here that usually has a lot of commercial type electronics,  and sometimes really old tube radios. I once picked up a ROULAND (note spelling) PA mix/intercom amp, ca. 1970 with a mic preamp, some aux inputs and a main output (I'm guessing would go to a separate power amp) Had a bunch of these really cool mechanical blinking eye type push button switch caps, I'll be using them for my frugal DOA melchoir build.

 

[gyraf]

Sadly, after implementing the EU weee-directive, it's no longer possible to pick up scrap electronics here in Denmark  Everything MUST be grinded to pieces and metal-recycled by certified companies.

My best dumpster-find was probably a TC2290 delay (working prototype) or a batch of seven small rosewood boxes containing a variety of Bruel&Kjaer capsules. Oh, and a stack of Bruel&Kjaer calibration equipment like pistonphones, barometers and sound level meters, most of which was used to kick mr. Campbell in the right direction in the beginning of his capsule business..

Well - back to this thread: VERY good idea for recessing power-trafo bolt!!

Jakob E.

 

[dissonantstring]

thanks riggler for this little tutorial.  great idea.  the thing that concerns me is...

I was home sick with pneumonia today, and was working on my SB4000. I came up with this idea for recessing the toroidal transformer mounting bolt. I hate having things sticking out of the case like that.

you should get rest while trying to nurse your illness, not DIY!    
but, i guess that's another illness we all deal with on this forum. ;D

 

[riggler]

Heh, DIY is the best therapy!

 

[kepeb]

that looks pro.
I did my last couple how Axel suggested back when,
http://www.groupdiy.com/index.php?topic=43313.msg539501#msg539501
who'd ave thought.

I also bought a cheap hand drill so I could fit stand-offs after bedtime. lower rpm doesn't make such a racket