Coolant Proof Machine Light

[awemawson]

  I'm supposed to be on 'light duties' so I thought that this was an entirely appropriate activity 

I decided that the internal lighting in the machining cabinet of my Traub CNC lathe was pretty dismal and needed improving. The original is a folded fluorescent tube, housed in a thick walled glass tube of about 2.5" diameter, with rubber bungs at both ends with the starter in the asembly but the choke mounted remotely.
 
Simples: buy another identical one and mount it at the other end of the machine cabinet. Well perhaps not as although available they are over £400 each 

So a home brewed design is called for. Impressed with the 'under cupboard' LED lights we've had installed in our newly built kitchen I thought that I'd investigate whats available.

Needs to be water and coolant proof, not deteriorate with oil, and stand the impact of swarf flying everywhere. So I thought that a polycarbonate tube with LEDs in side should fit the bill, but what LEDs ?

A bit of research seemed to imply that the best 'bang for your buck' comes from rolls of 'SMD' LEDs that come on a roll of 300 complete with a self adhesive backing.

Quick test showed that they were certainly pretty bright:

[awemawson]

Initially my thoughts were to make a short stumpy one like the original, but then I realised that with the long coil I could make one the entire length of the enclosure from headstock to tailstock. A quick calculation revealed I could do this length three times with the coil, but how to mount them?

I hit on the idea of a central 'core' of plastic rod, with the threes strips glued on at 120 degree intervals then slid inside a suitably sized outer sheath of polycarbonate. Turns out 6mm core nicely takes the three strips round it's periphery and will slide inside a 16mm bore sheath. Handy as 16mm bore can be obtained in 20mm outer diameter which will allow standard conduit fittings to be used for mounting.

A quick 'bench test mock up was done:

[awemawson]

OK that's working well. I decided to leave it on to see if it ran cold, warm, or too hot!

Well the answer is slightly warm but not hot so that's ok.

Er - actually no, it's not ok - now that the glue has slightly warmed up some has got onto the outer sheath and I cannot withdraw the assembly to trim lengths and fit end caps 

No big issue as the LEDs are quite cheap - so I bullied it out, breaking the LED strips as I did it and ordered some more.

While they were on the way I made up some suitable coolant proof end caps. The 'non wire' end is just a plain black Nylon 66 plug turned to 16mm with a single 'o ring' groove. The cable end was similar, but I decided to use two 'o rings' for greater pull out resistance, and incorporate a small  IP66 cable gland.

[awemawson]

So when the new roll of SMD LEDs arrived, first I re-terminated it with suitable two core cable with a heavy oil resistant outer. This is not armoured, which ideally it should be, but I reasoned that as I am bringing the cabling out at the tailstock end, there will not be too much swarf flying around, and in the worst case scenario of cable puncture and shorting, it's only 12v DC, fed from a fused and short circuit proof power supply.

[awemawson]

It just so happened that there were some suitable 6mm  tapped holes in the 'roof' of the enclosure to support the assembly at the centre and tailstock end, but nothing at the headstock end.

Easiest way forward was to fix a 20 x 25 mm aluminium alloy bar to the inside roof using the existing holes, and use that to locate a third hole at the headstock end - height was about 35mm different, so a 25mm diameter spacer tapped 6 mm both ends was bolted to the inner roof and used to take the front of the bar.

This has allowed me to fix standard 'conduit clips' every 300 mm to the bar to take the light assembly which I think will give adequate support.

[awemawson]

Yet to fix it on as currently I'm banned from the workshop  by her in doors 

Actually I'm still waiting for a couple of 'din rail mounting clips' to fix the power supply to one of the existing din rails in the control cabinet.

The power supply is an approximately 1.25" x 4" x 6" 'brick'  Chinese made 12v 5 amp switch mode one sold widely but I got mine on ebay for less than £10 including postage - actually seems quite well made but they haven't given mounting much thought in the design as the only available tapped holes are down the 1.25" side, but I'm sure I'll overcome that 

[Pete.]

Pretty damn cool. I have a roll of those LED's, mine has a remote control and can output any number of different colours including disco flashing etc, and a brightness control too. Are yours the same Andrew or are they a fixed colour and brightness? I'd like to get a basic white set for a similar task.

[awemawson]

No I went for the brightest, which are mono coloured 'daylight'.

Also they are in groups of three across the 12v DC each with an smd resistor, so a single failure will only stop that group of three rather than the entire chain.

I have some LED "bayonet replacement" light bulbs that I installed in our letting holiday cottages, as guests will insist on leaving lights on when they go out for the day. They are a chain in series across bridge rectified mains, so a single led failure extinguishes the lot! So far I've had 10% failures over less than 6 months, but have devised a repair method. The cover pops off exposing a circular board packed with leds. When only one has failed I put a blob of solder across it to restore the rest. When I get to multiple fails, I'll keep one as a donor and nick it's leds. These are expensive bulbs at about £4 each so yes I'm a cheapskate but it's worth it!

[chipenter]

Last Thursday Lidl had led lights on special 240 and 12 volt , fitted up two over the lathe really bright and only 3 watts , led are getting brighter and cheaper got them all over the workshop .

[tom osselton]

Yet to fix it on as currently I'm banned from the workshop  by her in doors 

Actually I'm still waiting for a couple of 'din rail mounting clips' to fix the power supply to one of the existing din rails in the control cabinet.

The power supply is an approximately 1.25" x 4" x 6" 'brick'  Chinese made 12v 5 amp switch mode one sold widely but I got mine on ebay for less than £10 including postage - actually seems quite well made but they haven't given mounting much thought in the design as the only available tapped holes are down the 1.25" side, but I'm sure I'll overcome that 

Just show her how much you want to get in the shop just go upstairs and hang a sheet out the window! 

[awemawson]

Just show her how much you want to get in the shop just go upstairs and hang a sheet out the window! 

She's got my best interests in mind in this case Tom 

[Pete.]

Cheers, I will look around for some bright white ones. Don't know ho wI missed the Lidl offer

[AussieJimG]

This looks like a great idea

Jim

[John Stevenson]

Just sent off for 50 metres, can't have Mawson outshining me.   

[awemawson]

So I crept out to the workshop and finished this one off at last. Mounted the PSU on DIN rail clips, pulled the cables through and fixed up the light tube.

A very great improvement in illumination.

Only thing I'd do differently were I to repeat the exercise would be to spirally wrap the self adhesive SMD led strips round the 6mm core like a Barbers Pole rather than have them in supposedly straight lines, as in fact they wandered all over the place and look wonky. Spiral wrapping would still fit inside the 16mm bore 20mm o/d polycarbonate tubing, and the lighting would be the same. Just slightly better aesthetically.


 

[daz]

Don't know where you guys got your LEDs from, but I got mine at http://www.jmgoods.co.uk/acatalog/index.html
Seemed a decent price to me and the delivery was pretty quick, also pretty good at giving advice etc and I spoke to him on the phone for around 20 mins to make sure I was getting the right thing for my application.

[vtsteam]

Andrew, drilling and tapping holes in the ceiling of an enclosure is good test exercise for incisions and the superglue they use these days instead of stitches.  If you feel something pop you can just use Loctite Blue and carry on.  It's in all the medical literature. 

How did you get a hernia in the first place? Uh don't answer that.....

[awemawson]

All holes were pre-existing in the enclosure Steve - I just adapted what was there. Anyway I'd already mounted the beam before surgery!

For what its worth my Doctor tells me hernias of this type (inguinal) are a manufacturing / design defect !

[vtsteam]

Well, that's better. I mean about the light fixturing! Take it easy, Andrew, we want you healed up and taking on unbelievably complex machine projects in short order. 

[awemawson]

Thanks Steve for the thoughts - yes I'm with you on that one, the sooner 'normal service' can be resumed the better, inactivity doesn't suit my psyche.

[Gadabout]

Well they did say "light" duties so you took that literally and made a new light for the Traub! Love the thread by the way on the Traub!

Mark

[awemawson]

It 'ain't finished yet chum - load more to bore you with! I'm still plotting and scheming 

Welcome to the forum by the way

[Gadabout]

Andrew, Thanks , I have been on the forum for a long time as a major lurker!, nothing unfortunately to contribute as I am in awe of everyone here and totally out of place skill wise, but i do love reading of others projects!

Mark

[BenH]

I really like this, sounds perfect to go in my toolbox.

[tom osselton]

Put a strip under the workbench so you can find the bit's we always drop!