Fender eyelet board sizing info

[EL34]

Here is how my Fender eyelet board lengths are determined

Modern resistors are shorter than vintage resistors
They are not able to span the wider gaps that vintage boards had
2 inches is about the max distance modern resistors can span
That's with a short bend at end end so you can drop the leads down into the eyelets
This is why the top eyelet row and bottom eyelet row are 2 inches apart on my Fender boards

Here is how the board size is calculated:
You take the Fender layout diagram image and scale it down so that the two eyelet rows are 2 inches apart and you end up with the length
The board length is a product of the scaling down of the Fender layout diagram image

Below is an image of a Pro 6G5A layout diagram
The two eyelet rows are 2 inches apart
The final board length ends up being 12.5 inches long once you scale the layout diagram image down so that the two eyelet rows are two inches apart.

All my board material is 3.125 inches tall
The layout is then centered in the middle of that 3.125 inches
You have some blank board along the top and bottom edges of the board.

My boards are not the same size as original fender boards
The sizes are all noted on the eyelet board page here.
https://hoffmanamps.com/MyStore/catalog/EyeletBoard.htm


If you want to modify any of the Fender eyelet boards, go to the DIYLC board and read up on how to do that
You can then have a custom board made
Here's the DIYLC board link
https://el34world.com/Forum/index.php?board=26.0

[sluckey]

Really helpful info. It might be useful to mention on the eyelet board order page that these Fender eyelet boards are not the same length as the original Fender boards.

[EL34]

I added a link to the Fender eyelet board page pointing to this board
https://hoffmanamps.com/MyStore/catalog/EyeletBoard.htm

[EL34]

Modern carbon comp and metal film both have shorter leads than older resistors


My image shows both of those types of resistors
Once you bend a short 90 degree bend at each end, 2 inches center to center is a good gap for eyelets.
If you wanted to use one of the modern resistors on a board with a gap wider than about 2 inches, you would have to add on lead lengths
That is really ugly and sort of a hack, but not much you can do about it.


So, modern boards should all be designed to accommodate the components that people will be using.
I knew this 25 years ago and that's when many of the older Hoffman boards were designed