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I built a 10 inch mini rack from aluminium extrusions

louwrentius.com

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Re: I built a 10 inch mini rack from aluminium extrusions

#21

Post by inickt »

addaon wrote: post #6

Why use the original power bricks, with the space claim and awful routing, instead of just going to a single dc/dc... either directly if no individual power control is needed, or to a relay block or switch block if automated / manual individual control is needed?

I remember seeing this great video where they built their own power supply for their mini rack. Quite a project but ended up being a pretty cool solution to the problem.

https://youtube.com/watch?v=8tTG0TBM7ts

https://www.reddit.com/r/homelab/comments/1qh13nu/i_made_a_p...

Re: I built a 10 inch mini rack from aluminium extrusions

#22

Post by doubled112 »

hydrogen7800 wrote: post #14
louwrentius wrote: post #7

Earlier quoted context omitted.

I haven’t found a solution for a single DC power supply I can connect to the systems. Maybe I have to solder something together myself.

Man, I spent a lot of time looking for something like this when i bought my NAS and got annoyed with all the power bricks. Guitar players use them[0] to power their several guitar pedals, but the polarity, voltage and plug form factors are all the same, as far as I know. The various devices i have use slightly different plugs, polarities and i think not all are 12VDC. I'm very surprised that nothing like this exists…

Most guitar pedals are 9V DC but not all.

Some are 12v. Some will take 18v. I have an oddball that takes 9V AC. Some are 9V DC but flip the positive and negative. It can be a mess too.

The product you link to has outlets for 9V, 12V and 18V.

If you stuck to one PC manufacturer, I’d imagine you could have your wish. Dell laptops were the same 19V and same DC pin for years and years.

I thought USB-C PD would save us but it has a few pitfalls, apparently.

Re: I built a 10 inch mini rack from aluminium extrusions

#23

Post by js2 »

addaon wrote: post #9
louwrentius wrote: post #7

Earlier quoted context omitted.

I haven’t found a solution for a single DC power supply I can connect to the systems. Maybe I have to solder something together myself.

Meanwell is the standard answer for this sort of thing; something in the SD-500 family or sized/optioned as you need. You'll have to do the connectors yourself; you may be able to find junction-post-to-barrel-plug leads of the right size and length off the shelf, but I'd be surprised, and soldering them would take less time than shopping for them.

The HP's power-supply is 19.5V:

https://www.ebay.com/itm/235241551377

The SD-500 is available in 12V, 24V, and 48V, none of which adjust to that range:

https://www.meanwell.com/Upload/PDF/SD-500/SD-500-SPEC.PDF

Also, not sure why you're suggesting a DC-DC supply here? His input is AC.

Re: I built a 10 inch mini rack from aluminium extrusions

#24

Post by jmarcher »

msisk6 wrote: post #15

These aluminum extrusions are called T-Slot, or as McMaster-Carr calls it, "T-Slotted Framing". Very common in industry; we have it everywhere on the Boeing factory floors. Not cheap, but very durable and reusable. Highly recommended. Check it out starting on page 2240 of your McMaster-Carr 132 catalog. They have all kinds of things you can mount up like monitor arms. It's an erector set toy for engineers. ;)

https://www.mcmaster.com/products/t-slot-framing-components/...

Re: I built a 10 inch mini rack from aluminium extrusions

#25

Post by ghostly_s »

jm4rch wrote: post #2

I didn't originate this idea, but if you're curious about other options... I found success using an IKEA Helmer for my home lab. https://www.ikea.com/us/en/p/helmer-drawer-unit-on-casters-b...

I have a couple of these, they are made of a light gauge sheet metal; the inner dimension is ~9.75", wider than the 10" standard hole spacing; and I don't think they would be very structurally sound if you were to remove the back panel. Doesn't seem very well suited to me.

Re: I built a 10 inch mini rack from aluminium extrusions

#27

Post by throwaway219450 »

bartvk wrote: post #8

It would be cool to design custom aluminum brackets for the fans. However I found that although ordering 3D prints is very cheap, using (for example) PCBWay for CNCing something out of aluminum is very expensive.

Try to avoid milling unless you absolutely need it. Better to go 2D with some tolerance and print small adapters, or use standard T-slot hardware, to connect it. It's often educational to browser McMaster just to get a feel for what standard parts even exist.

For a bracket I would look at a laser or waterjet service. Sendcutsend is one of the more well known web shops and the pricing is OK for the convenience. Also look out for local places that are linked to education. Some libraries even have laser cutters. One shop near us will do simple jobs for machine time + material cost, like you give them a DXF and they'll cut acrylic for a good price. Other option for metalwork is to join a makerspace. The dues are often very reasonable vs trying to get a lathe into your house.

Re: I built a 10 inch mini rack from aluminium extrusions

#28

Post by neilv »

jm4rch wrote: post #2

I didn't originate this idea, but if you're curious about other options... I found success using an IKEA Helmer for my home lab. https://www.ikea.com/us/en/p/helmer-drawer-unit-on-casters-b...

IKEA CORRAS FTW. https://www.neilvandyke.org/machine-learning/super-in-ikea-c...

Re: I built a 10 inch mini rack from aluminium extrusions

#29

Post by zeckalpha »

doubled112 wrote: post #22
hydrogen7800 wrote: post #14

Earlier quoted context omitted.

Man, I spent a lot of time looking for something like this when i bought my NAS and got annoyed with all the power bricks. Guitar players use them[0] to power their several guitar pedals, but the polarity, voltage and plug form factors are all the same, as far as I know. The various devices i have use slightly different plugs, polarities and i think not all are 12VDC. I'm very surprised that nothing like this exists…

Most guitar pedals are 9V DC but not all. Some are 12v. Some will take 18v. I have an oddball that takes 9V AC . Some are 9V DC but flip the positive and negative. It can be a mess too. The product you link to has outlets for 9V, 12V and 18V. If you stuck to one PC manufacturer, I’d imagine you could have your wish. Dell laptops were the same 19V and same DC pin for years and years. I thought USB-C PD would save us b…

Pedal polarity is inverse of typical barrel plug polarity though.

Re: I built a 10 inch mini rack from aluminium extrusions

#30

Post by zeckalpha »

ssl-3 wrote: post #26
someonebaggy wrote: post #19

Earlier quoted context omitted.

the whole thing?

Which part do I mount one of these 10" rack-mount switches[1] to? [1]: https://mini-rack.jeffgeerling.com/#network-gear

Any of it. TFA references https://loganmarchione.com/2025/09/homelab-10-mini-rack-v2/ which uses standard 10" shelves.
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