i'm on a roll... the kgsshv

[charlo89]

Only terrorists and pedophiles put the volume knob on the left.

CT = Center-tap.

I am not a pedophile because I'm 16, so it means I'm a terrorist

Cool front panel design, reminds me of the Pass Labs stuff.

Kevin Gilmore told me the same thing when I sent him the plans long ago (almost a year) I had problems with my Senn HE60 and I had abandoned the project, but today is finished and my stax 007mkII asking me for a good amp.

center tap is optional.

and i have an even newer and slightly simpler high voltage supply coming soon.

less parts, and the battery thing flipped upside down, and reference is now lt1021-10

because in fact it outperforms the lm4040-10 by a major amount.

Long story on the lm4040 part...

I await it eagerly, I would like to know if there was an update of the BOM since the first version.

[Lil Knight]

I am not a pedophile because I'm 16, so it means I'm a terrorist

16 years-old with HE60 and O2? Man, kids these days...

[justin]

Only terrorists and pedophiles put the volume knob on the left.

CT = Center-tap.

i agree but i feel the same way about input selectors

he can't win!!

[Bidoux]

I'm in favor of the left volume control for left-handed people.

[Spychedelic Whale]

The last version is final right, if so is there going to be a group buy any time soon ? my O2 are starting to feel lonely

Edited May 6, 2011 by Spychedelic Whale

[ujamerstand]

Let's wait till Dr Gilmore is happy with the PSU.

[manaox2]

Let's wait till Dr Gilmore is happy with the PSU.

Definitely. And the digital attenuators to be paid in my case.

[El_Doug]

fyi, the hifi2000 case doesnt mesh with justin's heatsinks. unless a ton of people want to (1) machine the cases themselves, or (2) want to buy a complete set of custom panels + hardware from fpe (very expensive), I say we forget them

[kevin gilmore]

the hifi2000 case is instead of justin's heatsinks, not in addition.

The 3U case should be big enough for one amplifier mounted to the side

of each heatsink and the power supply board on the bottom. Two smaller

power transformers or one bigger one. I'll be ordering one of these

chassis soon. From birgirs dimensions, everything should just fit.

But just barely.

Justin's heatsinks would be used for a completely custom case, and

this is a whole bunch of work i don't want to get involved in at the moment.

[El_Doug]

I realize that the hifi2000 option is distinct from a custom option - however I was hoping against hope that Justin's heatsinks could fit into the hifi2000 case, thus giving us the best of both worlds. I have the measurements for the heatsinks, and bought one of the hifi2000 3U cases (their dxf files are a joke), and the amount of work to get them together is just insane. I was secretly hoping this would be an option for us to use his heatsinks without anyone needed to do custom machining. I was just letting everyone know that it would not be so simple, and that the universe did not grant us sufficient luck in this case.

the hifi2000 case is instead of justin's heatsinks, not in addition.

The 3U case should be big enough for one amplifier mounted to the side

of each heatsink and the power supply board on the bottom. Two smaller

power transformers or one bigger one. I'll be ordering one of these

chassis soon. From birgirs dimensions, everything should just fit.

But just barely.

Justin's heatsinks would be used for a completely custom case, and

this is a whole bunch of work i don't want to get involved in at the moment.

[charlo89]

I already ordered a hifi2000 case with external heatsink, but it was an horror, impossible to drill it. In addition, if you want to attach a component, you must completely cross (if you succeed) the heatsink and put a nut on the outside.

I finally fixed anything, but they are beautiful :mrgreen: , and I think taking them just for aesthetics and by not setting anything on it unless you bring me the solution

[kevin gilmore]

Those heatsinks absolutely do have to be NC drilled and NC threaded.

At a minimum a desktop manual mill preferably with digital readout.

No way to use a hand drill.

Its unlikely that the .5 inch spacing is going to line up with the

fins, so no way to put nuts on the other side.

[El_Doug]

so in other words, if we don't want to pay a fortune, and aren't super-chummy with Kerry, we should really consider the on-board heatsink version?

[ujamerstand]

I wonder if modushop could do work on the heatsinks. I see plenty of people on diya do this by themselves, how do they do it?

[digger945]

how do they do it?

I don't know how "they" do it, but I tried, and succeeded drilling and tapping my Conrad heatsinks by hand. It took me about 40 hours to learn how to remove broken drill bits and broken taps. After fouling up several holes, I was then left with having to make every hole the next size larger. Some heatsinks can be stubborn to work on by hand.

My advise would be to let someone else do the heatsink machining work for you. At the end of the day, I myself would be time and money ahead to just lay it out in FPE and let them do the work on the chassis as well. Otherwise use the onboard heatsinks, or get creative with something like the Aavid clip max system, etc.

[ujamerstand]

University's MIE lab it is, I guess.

[Horio]

My advise would be to let someone else do the heatsink machining work for you. At the end of the day, I myself would be time and money ahead to just lay it out in FPE and let them do the work on the chassis as well. Otherwise use the onboard heatsinks, or get creative with something like the Aavid clip max system, etc.

Can FPE drill/tap heatsinks? Man this would be handy if they did. I just assumed there would be issues with clamping the heatsinks into their machines.

After doing some minor drilling & tapping on some heatsinks for one of my other builds, I definitely agree that it is worth it to have someone with the right equipment do it.

[DouglasQuaid]

I assume it's still perfectly capable of mounting to an angle bracket for those of us without industrial grade mills.

[nattonrice]

If you have a drill press (with a depth stop) then you can cheap out like I do and just get a local machine shop to "spot" the sinks from your cad file.

They use a small pointed bit to put a "spot" / dot at the center of each of the holes to be drilled to which you can use a standard 3mm center punch to make the dots physical marks so that when you drill the holes the bit won't wander. You can follow up with tapping by hand.

If you are worried about tapping off angle then grab a piece of 19mm (3/4") mdf and put the exact same hole in it: dadaa tapping jig.

As long as you drill the correct sized clearance hole in you sink and use a drop of machine oil you'll never snap a bit.

Anyway it takes a machinist about 5min per sink (or less) and ends up costing $10 to get done instead of what ever ludicrous price they charge to drill and tap.

Edited May 7, 2011 by nattonrice

[kevin gilmore]

kerry's thing cannot do the kind of drilling and tapping necessary.

On the other hand, nate has a desktop with DRO. Perfect for

using a center drill on all the holes (required) and then drilling

the holes.

Tapping by hand is absolutely no problem as long as you have a chunk

of metal at least 1 inch thick already drilled with the exact body

size of the tap. Only way to keep the tap straight. And if you keep

the tap straight, you won't snap it.

I have a mill at home without a DRO, so i do it the old fashioned way

and pay attention to the knobs.

The NC machines just make it easy and fast.

[Pars]

I drilled and tapped my Pessante heatsinks with just a drill press and hand taps. Blind bores, used a bottom tap. Not perfectly straight (didn't use the 1" block of metal suggested by Kevin above... good tip). Didn't break any taps on 3 mounting holes (for the angle brackets) per sink. Would probably want a better method for more holes such as what I guess you are talking about, but if you take your time and work carefully, it could probably be done.

Edited May 7, 2011 by Pars

[Kerry]

I've done the heat sinks by hand and with my mill. Both are not easy.

By hand is actually a lot faster for me, but less accurate. Even if I have highly aligned center taps for each hole, the drill bits still wander a bit. I find it easier if you drill the part you will mount first (side rails, heat sink mounting rail) and then secure them to the heat sink and drill on the drill press to start the holes (about 1/8" deep). A lot of what I do is by feel and I've had a lot of experience (first with woodworking and now with aluminum) so I'm able to get away with this.

The mill on the other hand perfectly places the holes, but I've never been able to perfectly align the heat sinks in the fixture (even with 45 minutes of prep time). I need to rethink the fixture I use for a heat sink. The time here is in preparing the CAD and then testing on the mill. Alignment takes real time too for me and my mill is pretty slow. Using a CNC mill takes lots of experience and I've got a lot of learning still.

I think I will mill a template out of 3/16" aluminum plate next time and secure that to each heat sink (something FPE could do for you). Secure it to the heat sink and use a drill press. This will be much more accurate for me and in the end faster.

Tapping holes by hand is as much artistry as it is technique. First time was a disaster, but I'm pretty good with it now. I don't really enjoy it since it is very time consuming.

I have a real respect for the CNC milling work Kevin did on the T2 chassis.

Edited May 7, 2011 by Kerry

[spritzer]

I agree with Kerry that tapping is very much an art, one you "get it" then it is pretty easy to do but it is still very time consuming. The dissipante boxes aren't that hard to work on, I use 4mm screws to secure the angle brackets and glue to secure the screws in place.

[kevin gilmore]

This is why GOD invented centering drills.

Even with my NC machines good for .0005 inch positioning,

without using the centering drills first, the wander is horrible

even when clamped to within about .5 inch of the end of the drill bit.

The problem with manual methods is first you have to use the

centering drill on all the holes, then go back and actually drill them.

Without a DRO, this takes a lot more time because you have to change

the centering drill and the real drill bit for every hole unless you

are confident enough in your positioning.

[charlo89]

are there a BOM for the last Kgsshv boards ?