Cutting hole in base of CD player

[bi-amp2]

I have done some serious mods to my Marantz CD63SE KIS. Reddish75, a member on the wam, has been of tremendous help to me. It is now a pain to take apart/remove all the new stuff to get at the pcb, which I need to take out in order to fault-find or solder anything new on the underside of the pcb.

I would like to cut a section out from the copper chassis just underneath the pcb. The player has an additional steel plate screwed below the copper chassis. I intend leaving the steel plate intact, which means that when I remove it, the cut-out section of copper would come out with it.

I don't know how to do it myself. I live near Warrington. Any ideas where I could get this done, or how I could do it myself? I would like a neat job, since so far everything has been done v correctly and following the Reddish book of best electrical engineering practice.

Thanks in anticipation...

 

[speedysteve]

How big a hole are we talking?

You can get hole cutters of say 70mm diameter for about £12-15. You will need an arbor for another ~£10.

Ideally you need a Pillar drill to it well. A cheap Draper type will do on a low gear / chuck speed.

You could then cut one or two or more holes (I assume you will remove everything from the chassis).

there are bigger - over 100mm but it is asking a lot of the drill esp if it into steel.

Alternatively you could get a punch nibbler. A lot work on compressed air but I have a drill one that works fine. I also have an air one which is lighter and a bit easier to use. You need a decent compressor to power them though.

You can cut any shape hole you like and it cuts cleanly. Start with a 10mm drill hole and off you go. Cost about £35. really needs a mains powered drill to work on steel.

e.g. http://www.ebay.co.uk/itm/DOUBLE-HEADED-SHEET-METAL-NIBBLER-FOR-DRILL-/300742118713?pt=UK_Hand_Tools_Equipment&hash=item4605a08d39

I'm too far away to help but any self respecting DIY'er should have these sorts of tools

 

[bi-amp2]

How big a hole are we talking?You can get hole cutters of say 70mm diameter for about £12-15. You will need an arbor for another ~£10.

Ideally you need a Pillar drill to it well. A cheap Draper type will do on a low gear / chuck speed.

You could then cut one or two or more holes (I assume you will remove everything from the chassis).

there are bigger - over 100mm but it is asking a lot of the drill esp if it into steel.

Alternatively you could get a punch nibbler. A lot work on compressed air but I have a drill one that works fine. I also have an air one which is lighter and a bit easier to use. You need a decent compressor to power them though.

You can cut any shape hole you like and it cuts cleanly. Start with a 10mm drill hole and off you go. Cost about £35. really needs a mains powered drill to work on steel.

e.g. http://www.ebay.co.uk/itm/DOUBLE-HEADED-SHEET-METAL-NIBBLER-FOR-DRILL-/300742118713?pt=UK_Hand_Tools_Equipment&hash=item4605a08d39

I'm too far away to help but any self respecting DIY'er should have these sorts of tools

Thanks, Speedy. The copper section I want to cut out would be approx 8 inches square with rounded corners. This in effect would be an inspection plate – I would remove it in order to fault-find and do further mods (so I don't have to remove the pcb) and then be able to put it back. This 'removable' section is not perfectly flat as it has indentations for feet, etc. so it might be 'tricky' to cut. I have a Black and Decker 'mains' drill, but I do not have a pillar drill.

The 'nibbler' as per your eBay link: does this fit universally onto any drill, and would this do the job? I envisage turning the player upside-down (firstly having removed all the innards and the bottom flat steel plate), securing the player somehow to my workbench, and then cutting it freehand with the nibbler attached to my drill. Is this the way to go?

 

[Cable Monkey]

The copper sub chassis has a purpose. I would be looking at a way of getting to the parts you need to without altering the structure of the player.

 

[bi-amp2]

The copper sub chassis has a purpose. I would be looking at a way of getting to the parts you need to without altering the structure of the player.

Thanks CM. Ideally, you are right – it would be preferable not to alter the chassis; but I have added many more components above the pcb (and bolted to the sides) that to remove the pcb is now a real time-consuming pain. I do not do this lightly. In any case, the section I wish to remove will be cut out, then screwed to the base steel plate which runs underneath it and then replaced in its original position. This will make it so much easier and quicker to get at the underside of the pcb.

 

[reddish75]

Find an engineer, get him to cut he shape out with he correct tools, then get the copper shield 'plate' welded to the bottom plate as discussed, neat and straight to the point, DO NOT try and cut this out yourself it could all end in tears.

 

[speedysteve]

Re the nibbler. Yes, any drill will do. You should practise first on a test piece of steel or if it is copper sheeting to be cut then ideally copper.

Practise following a line and smooth curve corner cutting. When you are a whiz at it then the real thing...

it depends on the indentations a to how the nibbler will follow. Hard to say but a 90deg step will be difficult. You could always use a jig saw on those sections.

There are probably some nibbler demo vids on youtube.

Also bear in mind that any saw or nibbler removes material. The nibbler removes a track about 2.5mm wide, punched out in small metal pieces. So the plate you have left will have the start hole and the track wide as a gap. This may not be ideal to use as a fit back in place panel...

 

[listenup]

Are you sure its a copper chassis?

From memory, the KI sig had a steel chassis plated with copper.

In other words, any chafe or filings or bits that fly around when cutting, will stick to anything magnetic.

Best done with the case empty methinks.

 

[Injector]

Seems like a mod too far...

 

[hearingisbelieving]

Are you sure its a copper chassis?From memory, the KI sig had a steel chassis plated with copper.

In other words, any chafe or filings or bits that fly around when cutting, will stick to anything magnetic.

Best done with the case empty methinks.

methinks the OP has already mentioned that he will empty the case before doing this.

Seems like a lot of work to go through but i know how difficult yet vital that access can be after extensive mods

 

[Who Cares?]

OP, any chance of some photos to show what you want to do and to clarify the copper stuff, does the copper need continuity such that having a cutout section would mean some straps for continuity.?

Me, I'd be tempted to strip it out and cut out most of the base leaving about a 20-25mm return flange and then get a piece of say 5mm steel, replicate any cooling slots, holes for fixing feet, have it painted to match the casing and fix that using 4mm nutserts in the flange, you could bond some copper plate to the steel plate. 5mm steel plate will give you a bit of extra mass which might be beneficial.

Any decent metalworking place will be able to do this stuff.

 

[bi-amp2]

Are you sure its a copper chassis?From memory, the KI sig had a steel chassis plated with copper.

In other words, any chafe or filings or bits that fly around when cutting, will stick to anything magnetic.

Best done with the case empty methinks.

I believe you are correct – copper plating only. Yes, I plan to empty the case completely before doing this.

 

[bi-amp2]

OP, any chance of some photos to show what you want to do and to clarify the copper stuff, does the copper need continuity such that having a cutout section would mean some straps for continuity.?Me, I'd be tempted to strip it out and cut out most of the base leaving about a 20-25mm return flange and then get a piece of say 5mm steel, replicate any cooling slots, holes for fixing feet, have it painted to match the casing and fix that using 4mm nutserts in the flange, you could bond some copper plate to the steel plate. 5mm steel plate will give you a bit of extra mass which might be beneficial.

Any decent metalworking place will be able to do this stuff.

I may be able to post pics later on – to do this I will need to remove everything from the player! The case comprises a removable top, a removable back, both of which I will not be altering, and front, base, and sides as 1 unit. As mentioned, I wish to remove a square from the base (directly under the pcb) of about 8 inches. Additionally, there is a steel plate, positioned under the base, that covers almost the whole of the bottom of the unit, which gives the player further rigidity. This plate is screwed to the base at its 4 corners and in the centre – luckily where the square cut-out section is located. So, when the square is removed, it can be screwed back onto the steel plate (and/or spot welded to the plate), and the steel plate screwed back in position. So, to access the underside of the pcb, all I need do is unscrew the bottom steel plate – 4 screws. And presto! The steel plate will come away along with the square that has been cut out.

Today I phoned a crash repair shop, and the guy seemed fairly confident he could do it. I have agreed to take it in for him to have a look at; but I will have to remove everything first!

Thanks for your postings/suggestions.

 

[Who Cares?]

I may be able to post pics later on – to do this I will need to remove everything from the player! The case comprises a removable top, a removable back, both of which I will not be altering, and front, base, and sides as 1 unit. As mentioned, I wish to remove a square from the base (directly under the pcb) of about 8 inches. Additionally, there is a steel plate, positioned under the base, that covers almost the whole of the bottom of the unit, which gives the player further rigidity. This plate is screwed to the base at its 4 corners and in the centre – luckily where the square cut-out section is located. So, when the square is removed, it can be screwed back onto the steel plate (and/or spot welded to the plate), and the steel plate screwed back in position. So, to access the underside of the pcb, all I need do is unscrew the bottom steel plate – 4 screws. And presto! The steel plate will come away along with the square that has been cut out.Today I phoned a crash repair shop, and the guy seemed fairly confident he could do it. I have agreed to take it in for him to have a look at; but I will have to remove everything first!

Thanks for your postings/suggestions.

Aah, getting clearer, a double base as standard if I understand correctly. If so, I'd just take a jigsaw with a fine steel cutting blade to the "interior" base. Mark well, drill at each corner to provide a radius and entry point for the blade, then go slowly. Needle file to clean all edges and remove any cutting marks, car touchup paint on the cut edges and that's it done.

To refix the cutout section to the exterior baseplate, yes you could have it spotwelded, be wary of distortiion though or just use epoxy adhesive.

 

[bi-amp2]

Aah, getting clearer, a double base as standard if I understand correctly. If so, I'd just take a jigsaw with a fine steel cutting blade to the "interior" base. Mark well, drill at each corner to provide a radius and entry point for the blade, then go slowly. Needle file to clean all edges and remove any cutting marks, car touchup paint on the cut edges and that's it done. To refix the cutout section to the exterior baseplate, yes you could have it spotwelded, be wary of distortiion though or just use epoxy adhesive.

Good suggestions. Thanks, WC. :^

 

[listenup]

How about fitting an iec inlet while its apart, as the standard cable is a bit puny?

 

[bi-amp2]

How about fitting an iec inlet while its apart, as the standard cable is a bit puny?

Good suggestion, and under consideration.

I have set up separate toroidals and power supplies in a separate case (with its own screened iec inlet) feeding different parts of the main player's circuit via cables with XLRs. I plan eventually to move all the AC into this sep case.

 

[stewartwen]

Maybe you should post some pix of the fine job you have done so far, and some pix of the bottom of the case you intend to cut.

S

 

[bi-amp2]

Maybe you should post some pix of the fine job you have done so far, and some pix of the bottom of the case you intend to cut.S

I will post some pics of the job so far when I have finished my next mod. Also, I will post pics of the bottom of the case when I next remove the circuit board... not an easy job!