Advice on internal Datacentre 1MHz bus cable installation?

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VectorEyes
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Advice on internal Datacentre 1MHz bus cable installation?

Post by VectorEyes » Mon May 21, 2018 1:08 pm

Hi all,

I bought a DataCentre a few weeks ago. I've finally arranged to get my Master 128 PSU recapped, so I thought it was high time I knuckled down and actually got it installed.

Maybe it's a completely stupid question, but I've hit something I'm not clear about. I'd like to mount the 1MHz cable internally, but the connector is on the outside of the case, for obvious reasons. As I understand it, this means I have to cut a hole in the case so I can plug the 1MHz cable into its socket, then have it immediately enter the case again, go under the motherboard and then round and up to the Datacentre board.

Are there any instructions, visual guides etc. that show exactly how to do this? There are plenty of images and videos of installed Datacentres online, but I have (so far) not found any images that show exactly how to cut the hole. Or have I totally understood the installations instructions?

I thought I'd ask here before bothering Mark from Retroclinic directly, on the basis that presumably plenty of people on here have done exactly this installation in the past!

(And many apologies if this is an embarassingly stupid question!)

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Lardo Boffin
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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by Lardo Boffin » Mon May 21, 2018 1:41 pm

I just had my Master refurbed by Mark and got him to fit it while he had it (and a Pi co proc and switchable os etc.) and here is how mine looks underneath. Note it is still in the antistatic bag - it literally just arrived!
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47A50E21-0B34-4998-8CE8-4044E2874421.jpeg
2E2C328F-2F24-40F9-9F59-917AA1462691.jpeg
BBC model B 32k issue 4, 16k sideways RAM, Watford 12 ROM board, Viglen twin 40/80 5.25" discs, Acorn 6502 coproc
BBC model B 32k issue 7, turboMMC, Opus Challenger 3 512k, Pi 3 coproc
BBC Master, Datacentre + HDD, pi co-proc

RobC
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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by RobC » Mon May 21, 2018 2:01 pm

I think Mark usually puts some card between the cable and the underside of the PCB and sticks the cable to the outside of the card using a glue gun (or similar). This prevents any of the legs/sharp bits of the the PCB from damaging the cable.

I copied this when mounting my Pi co-pro inside my model B.

VectorEyes
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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by VectorEyes » Mon May 21, 2018 2:12 pm

RobC wrote:I think Mark usually puts some card between the cable and the underside of the PCB and sticks the cable to the outside of the card using a glue gun (or similar). This prevents any of the legs/sharp bits of the the PCB from damaging the cable.

I copied this when mounting my Pi co-pro inside my model B.
Ahah, thanks, and thanks Lardo Boffin for the pictures.

The printed instructions do explicitly mention that there's a piece of the case (internally) that you need to cut out to avoid the PCB pins being pressed down into the cable, and now that I've seen pictures I understand that it really is just a case of carving out an appropriately sized slot just about the interface connector.

Could anyone who's done this before tell me what tools they used? Are there recommended tools for carefully hacking sections out of old plastic computer cases? :)

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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by RobC » Mon May 21, 2018 2:56 pm

VectorEyes wrote:Are there recommended tools for carefully hacking sections out of old plastic computer cases?
I used a dremel type tool (actually a Proxxon) when I modded my A4 case. It's good for removing large amounts of plastic quickly and then you can tidy the edges up with a file.

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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by VincentVega » Mon May 21, 2018 6:03 pm

VectorEyes wrote: Could anyone who's done this before tell me what tools they used?
I used a normal Stanley knife. It's rather a crude tool for such a job, but it was good enough. I cut vertically first at either end of the connector. with the bottom of the case in its normal position. Then I went horizontally between the two vertical cuts - I had to go over and over until I finally broke through the plastic. It's massively thick, but my knife isn't the greatest so it took far longer than it should have. I finished off with a file to try and tidy up a bit. I didn't bother with any card, though having read the posts previous to this one, perhaps I should add some.

A Dremel would definitely be easier and neater, but the Stanley knife was all I had to hand.

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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by rharper » Sat May 26, 2018 3:45 pm

VectorEyes wrote: Could anyone who's done this before tell me what tools they used?
I used a Stanley knife and a chisel to do the same job.
Ray
Edit: I did this on the case without the motherboard.
Last edited by rharper on Sat May 26, 2018 5:49 pm, edited 1 time in total.
Raycomp


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1024MAK
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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by 1024MAK » Sat May 26, 2018 5:41 pm

I used a jack hammer and a nail file :mrgreen:

Joking aside, when cutting ABS cases, depending on the size of the hole, I use the following tools:
  • Junior hacksaw,
  • Metal file (I have a selection from normal size metal files to small 'craft' types and needle files),
  • Small flat bladed pliers,
  • Jigsaw with a clean cut wood blade,
  • Mini 12V drill (designed for drilling PCB holes) fitted with a cutting disc (but this is hard to use without accidentally damaging the other parts of the case),
  • Electric battery drill, or the mini 12V drill, with suitable drill bits (useful for drilling a series of holes, which you then can cut through with a hacksaw blade, or just snap off),
  • Sometimes a Stanley knife (but not recommended, as it's easy to slip and damage something else).
The easiest is to use a knife to score the case where you want the final cutout to be. Then use a junior hacksaw to cut a series of slots about 3 to 4mm apart at 90o to the slot, but don't go all the way to where you want the final cut. Then use the pliers to rock each bit of the cut case backwards and forwards until it breaks off. Then when all these bits are gone, use suitable files to finish the cutout until square and smooth.

Mark
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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by shakesc » Tue Jun 05, 2018 6:04 pm

Hello
I have Master with a PiCopro and a datacentre
I haven't mounted the datacentre yet just but wondered if anyone had mounted it so it fixed to the mainboard and not the lid

Looking at fitting an SD adapter to it and Econet at some stage just to fill up the case :)

Pics would be great :)

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Elminster
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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by Elminster » Tue Jun 05, 2018 7:02 pm

Didn’t Simon Inns (simoni) do that. I am sure I remember him saying he did.

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Elminster
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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by Elminster » Mon Jul 16, 2018 9:56 am

Would a dremel be good for this? I dont actually own a dremel but people seem to love them. (I do have the profession Borsh equiv bu I think a 4 inch cutting blade might be a little big!)

I am looking at doing this myself now, although for BeebSID rather than DC.

I assume people are bringing the flat cable up between the back of the motherboard and the plastic sheet with all the port names on it (cant think what you would call this). Looks a very tight fit but cant see anywhere else to bring the cable up.

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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by KarateEd » Tue Jul 17, 2018 11:49 am

If you look at various installations on eBay that Mark sells, you'll see how he does the cabling as he puts quite a bit of detail in his sales.

It will become quite clear how to do it for the cable. You don't need to cut any holes to make this work. For the USB port, yes, on a Master, some small cutting. That should be visible also on some of Mark's pictures.

Ed...... :-)
Last edited by KarateEd on Tue Jul 17, 2018 3:47 pm, edited 3 times in total.

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Elminster
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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by Elminster » Tue Jul 17, 2018 12:11 pm

KarateEd wrote:
Tue Jul 17, 2018 11:49 am
It will become quite clear how to do it for the cable. You don't need to cut any holes to make this work. For the USB port, yes, pm a Master, some small cutting. That should be visible also on some of Mark's pictures.
If you scroll up a bit you can see a picture of the DC connected to a master by Mark and he has definitely cut the case for the cable to fit.

Edit: Also remind me now, I remember seeing DC came up on the right hand side, but as I want to swing the case backwards, not sideways. And I was the Beebsid more on the left to reduce cable. Hmmm. The problem on the other side is I plan to fit internal beebscsi, so not sure where I can route the cable there.

Edit2: this is due to location of desk, the case can only really open backwards. Unless every time I want to open it I remove all the cable and move it elsewhere. All a bit pain.
Last edited by Elminster on Tue Jul 17, 2018 12:20 pm, edited 2 times in total.

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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by KarateEd » Tue Jul 17, 2018 3:50 pm

Ah, so he has. Funny, you don't have to do that on a Beeb. Are they that much different in the tolerances?

Ed...... :-)

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Elminster
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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by Elminster » Tue Jul 17, 2018 3:55 pm

KarateEd wrote:
Tue Jul 17, 2018 3:50 pm
Ah, so he has. Funny, you don't have to do that on a Beeb. Are they that much different in the tolerances?

Ed...... :-)
Not sure. Need to get a Beeb out of storage to fit a 177x disk kit i bought about 4 years ago at somepoint this week. Will have a look. But there is no gap on master, not on mine anyway.

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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by VectorEyes » Tue Jul 17, 2018 4:14 pm

Funny that this thread has come back to life today. I literally just borrowed a Proxxon cutting tool to make the necessary cuts in my Master's case.

The Datacentre installation documentation says that you only need to cut the slice out of the case if you're routing the cable underneath the motherboard in a Master. Apparently if you have a Beeb, or you're routing the cable above the motherboard in a Master, you don't need to cut anything. That being said, when I was looking at it last night I couldn't see much space to fit the cable if I wanted to route it above OR below. Either some Masters have more tolerance than others, or you really can fit the cable between the case and the motherboard but it's not ovious until you try it.

As an aside... can anyone tell me whether it's possible to detach the motherboard from the case fully without desoldering the composite connector?

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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by danielj » Tue Jul 17, 2018 4:17 pm

The backplate of the master's motherboard is attached to the motherboard so you don't need to desolder anything. You either have to unscrew it or desolder it on a beeb though.

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Elminster
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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by Elminster » Tue Jul 17, 2018 4:37 pm

I am sure people were routing cables internal on Beeb in ye olde days, so not sure why when Acorn followed with master they made it harder. Maybe because with all the extra internal expansion and cart slots on master they thought people wouldn’t do it any more.

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Elminster
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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by Elminster » Tue Jul 17, 2018 8:54 pm

Elminster wrote:
Tue Jul 17, 2018 3:55 pm
KarateEd wrote:
Tue Jul 17, 2018 3:50 pm
Ah, so he has. Funny, you don't have to do that on a Beeb. Are they that much different in the tolerances?

Ed...... :-)
Not sure. Need to get a Beeb out of storage to fit a 177x disk kit i bought about 4 years ago at somepoint this week. Will have a look. But there is no gap on master, not on mine anyway.
I can confirm. You could drive a bus through on the Beeb, but the master is almost no gap.

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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by VectorEyes » Tue Jul 17, 2018 9:14 pm

Elminster wrote:
Tue Jul 17, 2018 8:54 pm
I can confirm. You could drive a bus through on the Beeb, but the master is almost no gap.
I see what you did there!

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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by KarateEd » Wed Jul 18, 2018 4:55 pm

VectorEyes wrote:
Tue Jul 17, 2018 9:14 pm
Elminster wrote:
Tue Jul 17, 2018 8:54 pm
I can confirm. You could drive a bus through on the Beeb, but the master is almost no gap.
I see what you did there!
That's funny. I had to get a good night's sleep to get it.....

Ed...... :-)

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Elminster
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Re: Advice on internal Datacentre 1MHz bus cable installation?

Post by Elminster » Wed Jul 18, 2018 4:57 pm

Perhaps I should have also said ‘there is not a bit of space between connector on master unless you take a bite out of it’ :D
Last edited by Elminster on Wed Jul 18, 2018 4:58 pm, edited 1 time in total.

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