Snap in caps in eyelet boards?
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- dragonbat13
- Posts: 410
- Joined: Tue Feb 27, 2007 1:38 am
- Location: Southwest Louisiana
Snap in caps in eyelet boards?
Is there a specific size eyelet to allow modern caps to be used on an eyelet board?
Mark Clay
Amature/Hobbyist/Electronics Hoarder
Amature/Hobbyist/Electronics Hoarder
- martin manning
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Re: Snap in caps in eyelet boards?
Ditch the eyelets and drill holes for the terminals per the data sheet dimensions. Then just solder leads to the cap terminals under the board.
- dragonbat13
- Posts: 410
- Joined: Tue Feb 27, 2007 1:38 am
- Location: Southwest Louisiana
Re: Snap in caps in eyelet boards?
I guess that is the best route.
I'm trying to hunt down a PCB Gerber file for an ODS that I know is on here.
I'm trying to hunt down a PCB Gerber file for an ODS that I know is on here.
Mark Clay
Amature/Hobbyist/Electronics Hoarder
Amature/Hobbyist/Electronics Hoarder
Re: Snap in caps in eyelet boards?
I use radials with leads for nearly everything, mounting them on their side, usually with turrets, but eyelets would work as well.
They take up a bit more room than if they stood on end, but all the soldering is top-side of the board & they are easily serviced. A little goop on the bottom keeps them nice & snug.
They take up a bit more room than if they stood on end, but all the soldering is top-side of the board & they are easily serviced. A little goop on the bottom keeps them nice & snug.
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SoulFetish
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Re: Snap in caps in eyelet boards?
you can get eyelets is many different diameters and lengths. The cap datasheets will give you the dimensions you need for mounting the caps (lead dia. and pitch - which is the length between the leads). Just make sure to specify enough diameter for the eyelets to fit whatever leads you think you'll be soldering, and enough length so that they will properly swage out on the surface of the board.
I used eyelets when I mounted box style radial film caps on a build. It is functionally fine and aesthetically beautiful, but do yourself a favor and build in service access to get to those if you need to. One thing I will never do again is under-the-board wiring unless there is an access panel on the chassis (ei. Ampeg V4s, etc.), or the board is easily lifted for service. Back then, I made the decision to build it that way based purely on vanity and hubris, thinking "with meticulous planning, I wont need to get under there again". But only after I built it, did I realize my plan sucked. This is the one I’m talking about here, where I was so close to throwing out my back window, and dancing around it while lighting it on fire: Anyways, finding creative ways to integrate modern radial components in handwired projects is worthwhile because of the quality, availability, size, and cost of modern components. I like the horizontal mounting by lonote. Looks great, and is built for easy servicing. What I did in my latest build was use mount the caps top down on the chassis, with the leads inserted straight up through terminal strips I bought from CEdist.
https://www.cedist.com/products/turret- ... ow-u-style
Used standoffs around the same length as the caps, and it works great. If I needed a little clearance I used washers, but it was all stuff I had around the shop. Two things I like about this approach is that it secures the caps from vibrations and shock, which goes a long way in preventing broken leads and solder joints. It also provides plenty of room to solder leads directly to the caps, you can implement good grounding schemes in a practical way.

I used eyelets when I mounted box style radial film caps on a build. It is functionally fine and aesthetically beautiful, but do yourself a favor and build in service access to get to those if you need to. One thing I will never do again is under-the-board wiring unless there is an access panel on the chassis (ei. Ampeg V4s, etc.), or the board is easily lifted for service. Back then, I made the decision to build it that way based purely on vanity and hubris, thinking "with meticulous planning, I wont need to get under there again". But only after I built it, did I realize my plan sucked. This is the one I’m talking about here, where I was so close to throwing out my back window, and dancing around it while lighting it on fire: Anyways, finding creative ways to integrate modern radial components in handwired projects is worthwhile because of the quality, availability, size, and cost of modern components. I like the horizontal mounting by lonote. Looks great, and is built for easy servicing. What I did in my latest build was use mount the caps top down on the chassis, with the leads inserted straight up through terminal strips I bought from CEdist.
https://www.cedist.com/products/turret- ... ow-u-style
Used standoffs around the same length as the caps, and it works great. If I needed a little clearance I used washers, but it was all stuff I had around the shop. Two things I like about this approach is that it secures the caps from vibrations and shock, which goes a long way in preventing broken leads and solder joints. It also provides plenty of room to solder leads directly to the caps, you can implement good grounding schemes in a practical way.

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- solderhead
- Posts: 160
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Re: Snap in caps in eyelet boards?
Once upon a time I tried spacing eyelets at the right distance to allow a snap-in cap to snap-in, being held by the edges of the eyelets. I quickly gave up on that idea and then decided I was better off just drilling holes at 10mm spacing and then snapping the caps into the board, and soldering to the caps' leads as you mentioned.martin manning wrote: ↑Sat Jul 26, 2025 4:20 pm Ditch the eyelets and drill holes for the terminals per the data sheet dimensions. Then just solder leads to the cap terminals under the board.
The problem comes with boards that are too thick. When I used boards that were too thick I found that the snap-in action wasn't very strong, and there wasn't much terminal sticking out beyond the board to solder to. This was much less of a problem with the thinner boards, which worked a lot better.
My problem was that I had a deep supply of thick boards, as I like thicker boards for their stiffness. to use snap-in caps with them I ended up counterboring a recess for the caps to sit in. I took out half of the board's thickness, and the snap-in functionality worked a lot better.
Sadly, I'm not doing this any more because the industry has moved away from high voltage snap-in caps in favor of low voltage devices. CDE has discontinued most of their high voltage snap-ins and replacements are getting harder and harder to find. I've spent so much time unsuccessfully trying to source high-voltage snap-in caps for amps that I'm resolved to give up on them -- the future seems to be in radial caps, as others have noted.
Better tone through mathematics.
Re: Snap in caps in eyelet boards?
One thing I will never do again is under-the-board wiring unless there is an access panel on the chassis (ei. Ampeg V4s, etc.), or the board is easily lifted for service. Back then, I made the decision to build it that way based purely on vanity and hubris, thinking "with meticulous planning, I wont need to get under there again". But only after I built it, did I realize my plan sucked. This is the one I’m talking about here, where I was so close to throwing out my back window, and dancing around it while lighting it on fire:
[/quote]
That's too bad, the layout is beautiful.
[/quote]
That's too bad, the layout is beautiful.
Tube junkie that aspires to become a tri-state bidirectional buss driver.
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SoulFetish
- Posts: 211
- Joined: Wed Apr 03, 2013 1:50 pm
- Location: Norwood, MA
Re: Snap in caps in eyelet boards?
That's too bad, the layout is beautiful.TUBEDUDE wrote: ↑Thu Aug 07, 2025 10:21 am One thing I will never do again is under-the-board wiring unless there is an access panel on the chassis (ei. Ampeg V4s, etc.), or the board is easily lifted for service. Back then, I made the decision to build it that way based purely on vanity and hubris, thinking "with meticulous planning, I wont need to get under there again". But only after I built it, did I realize my plan sucked. This is the one I’m talking about here, where I was so close to throwing out my back window, and dancing around it while lighting it on fire:
[/quote]
That's kind of you to say, I appreciate it.
It would have been great if it was as quiet, stable, and sounded as good as it does today. Clean work is still important to me, but it looks nothing like that. It was an important and freeing lesson for me to learn.
Re: Snap in caps in eyelet boards?
The sound is the crucial attribute. My ptp builds are fugly. Toneful and quiet though.
Tube junkie that aspires to become a tri-state bidirectional buss driver.
Re: Snap in caps in eyelet boards?
I've been using Snap-in caps in eyelet boards for years. I don't rely on the snap-in feature to hold the caps to the board. I just use the Keystone 40 series 1/8th inch hole eyelets. You can fit four or five #20 or #22 USWG bare wires in the eyelet to make a nice tight star ground on the negative terminal. I usually straighten the little bend in the cap's terminals and solder them in like you would any component. I usually mount the snap-ins on a separate board so it's not such a big job when you have to pull the board to replace the caps.