MOTM

The way I personally approached this tolerance issue is this. I designed
and built the cabinet, making sure to leave a "little extra" play around
all four sides of the front panels. Not quite an eighth of an inch on
each side I think. You don't want to cut that too close.

With the flat rails and a bunch of unfinished 2u panel blanks, plus
whatever panels I had from modules I haven't started building yet
(there's always a backlog in my studio, Stooge panels for modules I
haven't converted yet, etc.) ... I screwed in a panel crossing over the
seam between each flat rail. So I ended up with a weird Erector-set
contraption with all of my flat rails exactly where they needed to be in
relation to each other, but with plenty of gaps between panels so that I
could get in there and fasten the rails to the wood.

I just tipped the cabinet onto its back, laid the rail/panel contraption
on top of it, and screwed it all down. When I removed the phony panels
and replaced them with real modules, everything fit perfectly, and I did
very little actual measuring. The eight-inch gap that I left seemed to
be right-on -- it's loose enough that the nodules do not scrape the wood
lip, but you do not really notice any gap either.

When you're putting the modules in for the first time, it goes a lot
easier to do it with the cabinet on its back. You can drop each one in,
move the arrangement around; wiggle them into place, etc., until it's
just right. Then go along and screw them all in.

When you go to tip the cabinet upright, it's amazing how much it now
weighs...!


-----Original Message-----
From: tontaub [mailto:egroups@...]
Sent: Monday, February 07, 2005 7:11 AM
To: motm@yahoogroups.com
Subject: [motm] Gap between Flat Rails?



Hi All,

I'm (finally!) just about to mount my first flat rails.

Since the mounting wholes on the front panels are bigger than the
screw's diameter there's some play when mouting.

When mounting several flat rails in a row, what's the nominal gap
between the rails?

And is the upper/lower edge of the rails flush with the top/bottom
edge of the panels?

My intention is to use one 2U and two 1U panels as templates, ie.
assembling panels and rails before mounting the rails.

Thanks a lot, :-) Michael.

Hi Ken,

> I just tipped the cabinet onto its back, laid the rail/panel
> contraption on top of it, and screwed it all down. When I removed
> the phony panels and replaced them with real modules, everything
> fit perfectly, and I did very little actual measuring.

don't laugh at me, but this is a very useful hint! ;-)
I just didn't think of it since my "prototype frame/box" simply
doesn't lay flat when tipping on it's back.
But finding a good support was easier than messing around whith the
contraption in a vertical position.

> When you're putting the modules in for the first time, it goes a lot
> easier to do it with the cabinet on its back.

Indeed! ;-)

> When you go to tip the cabinet upright, it's amazing how much it now
> weighs...!

Yeah - I'm just about to scrap my cabinet ideas and rethink
everything. I need it really portable and 3x12U per cabinet get's too
heavy.

Thanks, Michael.

Quoting "Tkacs, Ken" <Ken.Tkacs@...>:

> Yeah, I made my cabinet out of oak; it holds two rows of 30u, and I
> need help lifting it. It's AMAZINGLY heavy!

60U in one cabinet? That's huge! I thought Larry's 2row slant cabinet
is big.
You got pics of it?

> My originally design was for smaller
> cabinets along the lines of the Moog IIIP system and I rejected
> those because I figured it was too much wood (and woodwork) but
> now I'm wishing I hadn't tried to stuff so much into one box.

hehe - I can see that. That's my thought. My original design is 3x12U
with Larry's Magic Bus incorporated. But I'm afraid that's going to be
too heavy.

> Of course, the fewer boxes you have, the fewer power supply hassels.

Yup, 1PSU per 36U is ok, but smaller units have some cabling overhead
and may cause headaches. I'll gotta think of it.

:-) Michael.

Quoting "Tkacs, Ken" <Ken.Tkacs@...>:

> I need to takes some. It's actually the first of three planned
> cabinets (I can't believe it myself but IU have enough modules &
> kits already to almost fill the second). And I've designed some
> "Mission-style" end pieces to suspend the three. Although now I
> question whether anything short of steel
> will be strong enough to hold three of these monsters!

Last August I met Alan McKerchar on the SDIY Meeting in Cambridge.
He brought his system which is 20U wide in 4 separate boxes.
Of course that's not as big as your synth but he had some laser cut
stands made of 4mm steel.
The stand itself was quite heavy but I have no doubt that it would be
able to support much more weight.

See here for some shots:
http://tinyurl.com/6r8qa

> I bought a couple of extra Power One supplies from Marlin P. Jones
> (overstock electronics outlet) at a good price, but frankly, the
> things are a mystery to me. I'm terrified of smoking something or
> starting a fire! I really need to
> figure them out, though, because I'm quickly running out of power.

what's the mystery? What PSUs you got?

> I've been building electronic kits since my PAIA days in the
> mid-70's, but I'm no engineer. The woodworking was more my style.

> The lighting in my studio stinks, but I'll see if I can drag it into
> the living room and take a few shots. Honestly, I cannot lift the
> thing. The way I move it by myself is to stand it on-end on top of
> one of my feet and walk it like that a foot at a time. I should drop
> it on a bathroom scale and see what it weighs just for laughs.

hehe, normally you would step on the scale with the object you want to
weigh in your hands (otherwise the result could be erroneous) and
subtract your body weight.
But honestly, when I read your lines, I can't picture that ... :-)

Maybe this is a good time to plug my form factor design page!

http://www.hotrodmotm.com/cab.htm

Moe

> hehe - I can see that. That's my thought. My original design is 3x12U
> with Larry's Magic Bus incorporated. But I'm afraid that's going to be
> too heavy.
>
> > Of course, the fewer boxes you have, the fewer power supply hassels.
>
> Yup, 1PSU per 36U is ok, but smaller units have some cabling overhead
> and may cause headaches. I'll gotta think of it.
>
> :-) Michael.

Hi Moe,

thanks for this reminder ;-)
Don't forget your PSU page. http://www.hotrodmotm.com/ps.htm

:-) Michael.

--- In motm@yahoogroups.com, "mate_stubb" <mate_stubb@y...> wrote:
>
> Maybe this is a good time to plug my form factor design page!
>
> http://www.hotrodmotm.com/cab.htm
>
> Moe