Circular Indent For Power Transformer Bolt

[funkymonksf]

Hello,

First off, I may not be using the correct terminology, so my apologies in advance.

I’m building a 2 channel tube pre in a console shaped enclosure. For the toroidal power transformer’s bolt I’d like to make it somewhat flush on the exterior as the bolt head is 3/8” tall and stands out.

Is there a way to shape an indent or bowl shape centered around the drill hole to make it more flush? The large washer is shaped like this.

I’ll try to get some pictures but my google searches are not bearing much fruit,

Thanks!

 

[Bo Deadly]

What you describe is called a "dimple die". Although the shaft of a typical dimple die is probably too big for a relatively small bolt. Instead, you could use a flathead screw as both a dimple die and bolt for the transformer.

More specifically, get two sets of a flathead screw, nut and fender washer that is ideal for mounting your transformer. Using the second set to make the dimple is recommended because it will likely be damaged and discarded afterward. Drill a clearance hole and large countersink in a soft piece of wood to use as the die.

 

[funkymonksf]

Thanks!

 

[13engrsapper]

Carriage bolt and a hammer or hydraulic press. It will not be flush, but it will be "flusher."

If you have a CNC you could make a custom dimple die for a hydraulic press - or Hammer I guess. I am assuming most guys with a CNC laying around also have a small hydraulic press.

 

[Tubetec]

A Clinch nut might work as a transformer mount ,

 

[mkiijam]

https://www.cleavelandtool.com/collections/all/dimple-dies
These are made for a hand powered tool, but you can stick them in anything and squueze away.

 

[KIDVOX]

A Clinch nut might work as a transformer mount ,
View attachment 104486

i use for many things. cheap adeffective

 

[KIDVOX]

often called nutserts or riv nuts

 

[swpaskett]

You might try a cup washer: McMaster-Carr
Or this: McMaster-Carr

 

[abbey road d enfer]

Most often, toroidal xfmrs include one or two cup washers, a screw and one or two nuts.
Mount the screw with a serrated washer and nut, then glue the cup washer to the panel using epoxy glue.
No need for specific tools.