slipperyflax
Well-known member
I did notice the same thing, metalwork from Kevin.
Reddish 500 EQ
- Thread starter JMan
- Start date
Help Support GroupDIY Audio Forum:
Now that we are discussing it, I am remembering that Frank suggested that those holes be drilled for M3.5 instead -- the reasoning, ironically, was related exactly what you guys are encountering (I didn't fully grasp the explanation, but since he does this professionally, I decided to just trust his expertise). I must have passed that same info on to Kevin as well. FWIW, I completely forgot about it, used M3 bolts on the units I built, and had no problems whatsoever, but it's good to know that a simple washer can address any issues that might arise.
That fixes one issue, but also creates another by pushing the PCB over another .9-ish mm. If those are 5mm long standoffs, I’d consider trying to source 4mm long to compensate if it’s tough to seat the module in the edge connector and still have the faceplate square with the rack. If the standoffs are aluminum you could also put a countersink bit in a drill press and take a little out of one end for the screw to recess in it, but that’s a pain. It may be fine how it is though.
Figuring out the metalwork is probably one of the most underrated aspects of our DIY journeys. I came across this same issue while designing the L-bracket for mine, when I realized that the head height of a standard M3 flat head is about 1.7mm. Even with a perfectly matched countersink on a 1mm plate you’re still left with .7mm sticking out. I remembered from putting together my CAPI kits that they use undercut flat head screws, so I’ve designed mine for 4-40 undercut screws that have a head height of about 1.01mm, because they were easier to source than M3 undercuts.
@thelivingroom I think this could actually be the solution to your Grayhill spacing comment. The additional washer under a 5mm standoff would provide that tiny bit of extra height to get them perfectly centered. Now, of course, that pushes the F2UEE switches out of place by a little, but a hacky-but-effective solution for this is to just assemble everything before soldering them, then use a finger to push them into alignment with the front panel (with caps on) while soldering the first pin or two. That technically means they'd probably be angled very slightly, but it will be so marginal as to be unnoticeable in practice. There is an inherent compromise between some of the mechanical aspects here, but I've been able to complete multiple units with very satisfactory results.
I thought about that too, and yeah, as you said one can just fudge a little here and there. I may be a bit too OCD; it’s the draftsman in me haha.
I totally get it! And I am always very impressed with your work.
janczmok
Well-known member
Thanks for the M4 Info... Another thing:
Some of you might have received the UTM3524 already. This brings me to the question of wiring:
CMOB-3S diagram states Brn-Red Primary, Orange Yellow Secondary.
UTM 3524: Pri: Red-Blk, Sec: Yel-Org
So i assume its on the PCB:
Yellow - Yellow
Red - Red
Orange - ORange
Brown - Black
Correct ?
Some of you might have received the UTM3524 already. This brings me to the question of wiring:
CMOB-3S diagram states Brn-Red Primary, Orange Yellow Secondary.
UTM 3524: Pri: Red-Blk, Sec: Yel-Org
So i assume its on the PCB:
Yellow - Yellow
Red - Red
Orange - ORange
Brown - Black
Correct ?
Oh, it sounds like the 3524 has different lead colors than the custom-wound 3523LP that was being ordered previously. That is good to know, I'll need to update the build docs with that info. Do you happen to have a data sheet? When I was writing the build guide, they hadn't published anything for the 3524 yet.
It sounds, from what you wrote, that it should be as follows, but if we can drum up a data sheet it would be good to confirm.
PCB: Yellow Red Orange Brown
3524: orange black yellow red
janczmok
Well-known member
Hopefully that means Red-Blk = Hi-Lo (and same for Yel-Org). As long as that's the case, what I wrote above should be correct.
janczmok
Well-known member
As we are waiting for the answer from UTM, i have received the grayhills from the other groupbuy here. I remember there was something to be modified. Can somebody provide info or links for the changes ?
I included a link to that thread in the build guide on the page about putting the Grayhills together. I don't have the link off the top of my head, but if you download the build guide you'll find it.
And yes, as janczmok mentioned, we are waiting for confirmation of the lead colors from UTM. For the moment, the build guide has a translation for the custom-wound UTM3523LP, but the 3524 has different lead colors, so we've reached out to them to get official confirmation of what was discussed in the posts just above this. Once we have that, I'll update the build guide.
And yes, as janczmok mentioned, we are waiting for confirmation of the lead colors from UTM. For the moment, the build guide has a translation for the custom-wound UTM3523LP, but the 3524 has different lead colors, so we've reached out to them to get official confirmation of what was discussed in the posts just above this. Once we have that, I'll update the build guide.
janczmok
Well-known member
very detailed info, thanks! Those are the grayhills from the groupbuy ( https://groupdiy.com/threads/group-buy-for-grayhill-71-series-3-deck-1-pole-switches.87293 ) so i am likely need to do this method -> https://groupdiy.com/threads/adjusting-the-non-adjustable-grayhill-switches.70952/
I wonder if the pin positions are the same for that method... Help appreciated as i am surely not the only one with those switches for the 500 reddish
I wonder if the pin positions are the same for that method... Help appreciated as i am surely not the only one with those switches for the 500 reddish
Last edited:
Yes, that is the correct method for the non-adjustable switches.
Once you remove the cover on the 12 position non-adjustable version (using the method outlined in Potato Cakes' thread), you'll find a single stop pin inserted at 12 o'clock. You'll simply need to add a second pin at 11 o'clock for the gain switches. While a sturdy clipped component lead can be used for this, you can also buy the actual pins from most major retailers. Here's a link if you're interested in that.
Once you remove the cover on the 12 position non-adjustable version (using the method outlined in Potato Cakes' thread), you'll find a single stop pin inserted at 12 o'clock. You'll simply need to add a second pin at 11 o'clock for the gain switches. While a sturdy clipped component lead can be used for this, you can also buy the actual pins from most major retailers. Here's a link if you're interested in that.
janczmok
Well-known member
I am having fun adjusting the Grayhills, but slowly i am getting used to it.
Soldering the 3524s now
Soldering the 3524s now
Forcemusicgroup
Well-known member
- Joined
- Sep 12, 2019
- Messages
- 94
Possible to get horizontal faceplates??
With the fpd file, you can open ithe file in the free Front Panel Designer software, change the orientation and anything else (add your name), save it and send it to Frank at front panels.de
https://www.frontpanelexpress.com/f...QIur0CwTvj2PhvJ1vF1d4dBD_R7UST9hoC-HwQAvD_BwE
https://www.frontpanelexpress.com/f...QIur0CwTvj2PhvJ1vF1d4dBD_R7UST9hoC-HwQAvD_BwE
Forcemusicgroup
Well-known member
- Joined
- Sep 12, 2019
- Messages
- 94
Appreciate that.
