Mellotronists

Hello - I'm now preparing to install some mounting brackets that I've 
made for the bottom of the spill box on 1407 and it's going to 
necessitate drilling through the bottom of the spillbox to attach the 
brackets.  I'm using some #10 machine screws, and I'm wondering if the 
head of the screw can/will cause any magnetizing problems inside of the 
spill box when tape is running through there.  I've noticed that the 
side mounting bolts were recessed with a forstner bit so they actually 
sit below the surface of the wood.  If the bolt head will cause 
problems, would it be okay to simply line the bottom of the box with 
felt or some other material?  It doesn't look like the bottom of the box 
is all that thick, so I'm a bit hesitant to attempt to make recesses for 
the bolts.

thanks,
john

--- In Mellotronists@yahoogroups.com, john barrick <astroboy@...> 
wrote:
>
> Hello - I'm now preparing to install some mounting brackets that 
I've 
> made for the bottom of the spill box on 1407 and it's going to 
> necessitate drilling through the bottom of the spillbox to attach 
the 
> brackets.  I'm using some #10 machine screws, and I'm wondering if 
the 
> head of the screw can/will cause any magnetizing problems inside 
of the 
> spill box when tape is running through there.  I've noticed that 
the 
> side mounting bolts were recessed with a forstner bit so they 
actually 
> sit below the surface of the wood.  If the bolt head will cause 
> problems, would it be okay to simply line the bottom of the box 
with 
> felt or some other material?  It doesn't look like the bottom of 
the box 
> is all that thick, so I'm a bit hesitant to attempt to make 
recesses for 
> the bolts.
> 
> thanks,
> john
>
  RE:  Hello again John:  Before we start, were there original 
brackets between spillbox and side panels? If so, why can't they be 
re-used?  
As far as mounting new screws on bottom of box, be caeful not to 
obstruct the divider plates as you will have clearance problems with 
spill box cover, you do have one I hope.  As long as you are not 
using a magnetized screwdriver there is not even a remote chance of 
any tape degaussing there. Just make sure the holes in brackets are 
sized to  allow for some adjustment.   Doug

Doug Berg wrote:

>
>   RE:  Hello again John:  Before we start, were there original
> brackets between spillbox and side panels? If so, why can't they be
> re-used?
> As far as mounting new screws on bottom of box, be caeful not to
> obstruct the divider plates as you will have clearance problems with
> spill box cover, you do have one I hope.  As long as you are not
> using a magnetized screwdriver there is not even a remote chance of
> any tape degaussing there. Just make sure the holes in brackets are
> sized to  allow for some adjustment.   Doug

  --------------------------------------------------------------------------------



Hello Again Y'all,

I've seen many M400's arrive here missing lower spill-box brackets.
They just happened to be "upgraded" by (un)Sound Sales long ago.

The earlier M400 series (approx. before S/N # 1234) with longer/thinner gauge
alum "L" channel metal suffered the most when spill box brackets were
removed. The entire structural integrity was compromised. This caused
frame sag on flywheel side, loose/crooked motor assy, wobbly wooden
end boards, misaligned spill-box,misaligned tape-path ,etc.

Orig. hdwe. to secure brackets to bottom of box were "carriage" type
bolts (no slotted heads to snag tapes).  As Doug mentioned, those bolts
are  recessed  to mitigate interference issues with spill box cover.

 Good Luck !   -- Jerry Korb   at the M-Ranch

Thanks Jerry and Doug.  The first Tron I looked at, 1210 (or whatever 
the one Bruce Daily now owns is) had the original mounting configuration 
of brackets at bottom and wood shims on the sides of the spill box.  
1407 has no evidence of the box ever having had bottom mounting brackets 
- there are no holes (or interior recesses) for either bolts or screws 
anywhere on the bottom or lower portions of the sides - it appears this 
box has always been mounted at the top - in fact, the holes that the 
bracket bolts screw into on the top of the frame are threaded, which 
makes the mounting scheme seem a bit more planned and less of a retrofit 
in New Jersey. 

If this is the case, is there any point to adding bottom mounting 
brackets (I've already cut and drilled them and was looking forward to 
putting them on)?  I can see that it could help add extra stability to 
the frame, but it doesn't appear to have been suffering any of the 
problems Jerry describes, except for the sagging motor which was 
remedied by tightening up the motor mount bolts.  The L channel aluminum 
I bought is about three times as thick as the original brackets, so it 
certainly wouldn't allow for much movement once installed.  The only 
reason that I used machine screws was because Home Despot didn't have 
small enough diameter carriage bolts to match what was already being 
used to mount the upper brackets.
best,
el johnno


Jerry Korb wrote:

>  
> ------------------------------------------------------------------------
>
>  
>
> *Hello Again Y'all,*
>
> *I've seen many M400's arrive here missing lower spill-box brackets.*
> *They just happened to be "upgraded" by (un)Sound Sales long ago.*
>
> *The earlier M400 series (approx. before S/N # 1234) with 
> longer/thinner gauge*
> *alum "L" channel metal suffered the most when spill box brackets were*
> *removed. The entire structural integrity was compromised. This caused*
> *frame sag on flywheel side, loose/crooked motor assy, wobbly wooden*
> *end boards, misaligned spill-box,misaligned tape-path ,etc.*
>
> *Orig. hdwe. to secure brackets to bottom of box were "carriage" type*
> *bolts (no slotted heads to snag tapes).  As Doug mentioned, those bolts*
> *are  recessed  to mitigate interference issues with spill box cover.*
>
> * Good Luck !   -- Jerry Korb   at the M-Ranch*
>  
>  
>   
>

john barrick wrote:

> Thanks Jerry and Doug.  The first Tron I looked at, 1210 (or whatever
> the one Bruce Daily now owns is) had the original mounting configuration
> of brackets at bottom and wood shims on the sides of the spill box.
> 1407 has no evidence of the box ever having had bottom mounting brackets
> - there are no holes (or interior recesses) for either bolts or screws
> anywhere on the bottom or lower portions of the sides - it appears this
> box has always been mounted at the top - in fact, the holes that the
> bracket bolts screw into on the top of the frame are threaded, which
> makes the mounting scheme seem a bit more planned and less of a retrofit
> in New Jersey.

  --------------------------------------------------------------------------------

Hi Guys,  Yep, engineering/design changes to M400 internals
occured around #1234. That's why  #1210 was orig.and #1407 was
new config.

That said, spill box cover on 1407 was designed for top mounting
only. Wooden side boards on 1407 are also thicker and more rigid.

The sad thing is that Sound Sales/Dallas attempted to incorporate
later M400 assembly into older units. Hence, the missing brackets,
wobbly board/motors, sagging frames, etc.  Calling it "upgrade" ,
it was reverse-engeering of the worst possible kind.

  --------------------------------------------------------------------------------

>
>
> If this is the case, is there any point to adding bottom mounting
> brackets (I've already cut and drilled them and was looking forward to
> putting them on)?  I can see that it could help add extra stability to
> the frame, but it doesn't appear to have been suffering any of the
> problems Jerry describes, except for the sagging motor which was
> remedied by tightening up the motor mount bolts.  The L channel aluminum
> I bought is about three times as thick as the original brackets, so it
> certainly wouldn't allow for much movement once installed.  The only
> reason that I used machine screws was because Home Despot didn't have
> small enough diameter carriage bolts to match what was already being
> used to mount the upper brackets.    best,  - el johnno

  --------------------------------------------------------------------------------

Definitely at your discretion, John.  1407 will only benefit from
further strengthing.  Make certain the wooden board that supports
the motor is rock-solid. I usually remove the 4 wood screws and
thru bolt the wooden board to alum "L" channel frame.

Attach some pix for us to see, John.  Will prob. be identical to #1332
which I refurbed here at the M-Ranch spring-2006.

Cheers, -- Jerry Korb (enjoyed some  yummy   Fowler's Mill pancakes)

Hi John:
Guess we established yours had no lower mounts.  703 had them and 
guess because of that aluminum channel of frame on capstan side showed 
no sign of stress or sagging as others suffered. With that said and 
seeing evidence of results without brackets, it would be a good idea 
to mount them and take extra support they provide. Also would be a 
good idea to drill holes in center of spillbox slots so you won't be 
interfering with dividers. If you like I can send pictures of 703's 
brackets, just let me know.  Take care, Doug