Apollo Construction Diary

[fredlock]

Originally Posted by ShinOBIWAN

Those baffle cut outs were done by 5 axis cnc because they're corian but with wood you could easily do the same thing with a mitre saw or a regular hand saw and some guides to run the blade up against. This is how I've done it in the past and it worked well.

Hi Shin,

Thanks for your reply. I'm just impress of how you build your speaker baffle. It looks so nice! The cnc that you put up together made it easier and quicker cutting the pieces compared to miter saw. I already build my cnc but haven't tested yet. It's smaller compared to yours, but I'm planning to use it on cutting aluminum for front/back panels of amps and drilling holes. If you don't mind asking you, how much did you spent building your cnc?

[ShinOBIWAN]

Originally Posted by fredlock

Hi Shin,

Thanks for your reply. I'm just impress of how you build your speaker baffle. It looks so nice! The cnc that you put up together made it easier and quicker cutting the pieces compared to miter saw. I already build my cnc but haven't tested yet. It's smaller compared to yours, but I'm planning to use it on cutting aluminum for front/back panels of amps and drilling holes. If you don't mind asking you, how much did you spent building your cnc?

Its complicated as there's been so many up's, downs and false starts with the cnc. Initially it was £4500 for the original but this was inadequate for my needs. Virtually all the important bits got replaced or upgraded. Quickly going through rough figures I estimate around £8500 give or take £500. Not what I'd budgeted for at all when I started out and that's mostly why its taken so long to get working.

[ShinOBIWAN]

Tweeter parts cut today. They're all assembled and glued but clamped and drying at the moment so I'll get a shot of those completed tomorrow.

Been playing with the CNC feedrates and depth of cut now I'm feeling a little braver. Trying to find the limit then from there I can back off for some safety margin. Currently upto 6.5m with 9mm depth of cut and it handles this no problem. Little worried about snapping the smaller 6mm cutters with much more than this though. Still haven't figured out how to do ramping in the CAM software yet though. Its there but I've only took a quick glance at the settings so far. Will invest more time in it at some point because although its only MDF at the moment if I'm doing a straight plunge into stuff like Alu then its gonna knock the hell out of the machine.

Apollo Tweeter Enclosure Cuts - YouTube

[c12mech]

This is looking really good now. The bracing reminds me of the Magico stuff except in MDF. I'm looking forward to seeing the finished product now. Can I inquire as to what it would cost or a set of these boxes? Not including drivers and crossovers. I'm curious since my wife actually likes the look of these speakers. And that is a BIG plus for me.

[ShinOBIWAN]

Its been an eventful day.

Broke my first bit through going too fast too deep. Its a bad idea to try 7m/min at 12mm depth with a 6mm bit. Bit stupid of me really since I've been told stick to around the diameter of the cutter as a safe area. Before the cutter broke I also noticed the quality of the finish starts to suffer when you go too far, sure the machine might move the cutter through the material no problem but its not rigid enough to handle those forces and that translates to the cutter and the work piece.

After the self inflicted drama the rest went smoothly.

They're starting to take shape now. This is one big speaker. Its testament to the fit of the bracing and rebates that none of this is glued or fastened in any way yet it still stands under its own weight. Pretty cool.

[Mark_A_W]

Fark I just made a mess

[sploo]

Originally Posted by ShinOBIWAN

Its complicated as there's been so many up's, downs and false starts with the cnc. Initially it was £4500 for the original but this was inadequate for my needs. Virtually all the important bits got replaced or upgraded. Quickly going through rough figures I estimate around £8500 give or take £500. Not what I'd budgeted for at all when I started out and that's mostly why its taken so long to get working.

Ant - really great to see you've got this up and running to your satisfaction (and it's well deserved for the work you've put into it). To make you feel a bit better: my machine, that's less than half the cutting bed size, and doesn't have a spindle (just a router) cost around the £4.5k mark in total. So you've arguably got at least twice the machine for around twice the cost.

How is that spindle holding up BTW?

Oh - your ducting is a little small for the static pressure loses over the lengths you have (you'd need a serious extractor to capture fine dust). However, the fact you've got the machine in an enclosure (which I presume is essentially sealed - albeit with an inlet valve - when you're cutting) is arguably better than any level of extraction, so I wouldn't worry.

I would however strongly recommend one of these http://www.trend-uk.com/en/UK/produc..._230v_uk_.html for the period when you're getting bits out of the machine and cleaning it out. It's made a huge difference to my cutting (well, lungs and eyes) and I wish I'd bought one years ago.

Originally Posted by ShinOBIWAN

Good idea. If anyone in the UK wants a small sample of Valchromat I have plenty of off cuts.

I'd be quite interested to try some - not that I'm getting much time to cut stuff these days .

Perhaps I could PayPal you some cash for postage + beer and you could chuck some in a box?

Originally Posted by ShinOBIWAN

Broke my first bit through going too fast too deep. Its a bad idea to try 7m/min at 12mm depth with a 6mm bit. Bit stupid of me really since I've been told stick to around the diameter of the cutter as a safe area...

They're starting to take shape now. This is one big speaker. Its testament to the fit of the bracing and rebates that none of this is glued or fastened in any way yet it still stands under its own weight. Pretty cool.

Yea, cut depth no deeper than the diameter is a good rule of thumb. I have seen guys using 1/2" chip-breaker bits at 3/4" DOC, but they're specialist things (and with hugely powerful spindles). General advice seems to be fastest linear speed possible (for reduced heat build up), rather than max DOC.

Also, deep DOC obviously gives more bit deflection (OK, fast linear does too), but for cuts that'll be visible you'd want a full depth finishing pass anyway.

Speaker looking absolutely superb, and yea - CNC is great for putting a box together to test with no glue. Got to say, what impresses me about your work is that the reality usually ends up looking like the render! My design process is usually back-of-fag-packet -> 2D drawing -> gcode -> MDF -> glue it -> run out of time to paint/veneer -> box sits in the livingroom under a table .

Oh - what's the tool changer system you've got? It's something that I've never set up, and has always limited me when it comes to doing designs. It's such a faff to change a bit half way through a job that I usually compromise by trying to cut with only one.

[c12mech]

HOLY CRAP!!! That thing is huge. I could tell from the render that it was big, but seeing it together in a room brings a better sense of the size. Patiently waiting for it to be finished and hear your listening impressions.

[ShinOBIWAN]

More cutting today. All the panels for the cabinet parts are now done. I'm moving on to the grills now and last off will be the base plinths and feet.

Last of the cabinet parts complete:


Grill frames for the 10" subs (the holes in the back will house neo magnets to secure the grill)

[ShinOBIWAN]

Originally Posted by sploo

How is that spindle holding up BTW?

Hey Gordon,

The spindle is great. Brilliant even. Never struggles and I've done silly things like rapid at 10m/min with a 12mm diameter cutter at about 15mm DOC and with the spindle running 11000rpm lol That was pretty scary and I hit the estop sharpish but even then it had carved about a foots worth of destruction. Its amazing how quickly things start to go wrong. I think even if you had the estop button between your buttocks you'd still not react quick enough

As far as the reliability goes you'll have to come back and ask in years time. I've heard the spindles are robust in the long term but the VFD is pot luck and can be problematic. Mine is holding up ok with the couple of weeks its been working. Early days yet though.

Oh - your ducting is a little small for the static pressure loses over the lengths you have (you'd need a serious extractor to capture fine dust). However, the fact you've got the machine in an enclosure (which I presume is essentially sealed - albeit with an inlet valve - when you're cutting) is arguably better than any level of extraction, so I wouldn't worry.

Its not pulling the dust as well as I'd like but I realised this when installing it. I did have a more grand extraction system planned but as the cnc started to show more and more problems my dust extraction budget disappeared! So this was put together on a shoe string. I did opt for a vacuum extractor with triple filtration since these filter down to 0.5micron at virtually 100% efficiency so none of the fine stuff is coming back out in to the workshop. Despite its lack of power for the CNC it has a couple of saving graces, one its extremely quiet and two it works very well for power tools.

And yes the enclosure is sealed where possible. I took all the lexan panels out and lined the edges with closed cell foam to help with that. Even without a dust shoe virtually nothing escapes when cutting and the are doors closed.

I would however strongly recommend one of these http://www.trend-uk.com/en/UK/produc..._230v_uk_.html for the period when you're getting bits out of the machine and cleaning it out. It's made a huge difference to my cutting (well, lungs and eyes) and I wish I'd bought one years ago.

I've looked at that before but to be honest I use these:

SprayDirect.co.uk | 3M Disposable Mask

The old man gets them from work for nothing so I've use 'em for a few weeks then throw away.

I'd be quite interested to try some - not that I'm getting much time to cut stuff these days .

Perhaps I could PayPal you some cash for postage + beer and you could chuck some in a box?

Sure, email me and we can sort the rest out.

Oh - what's the tool changer system you've got? It's something that I've never set up, and has always limited me when it comes to doing designs. It's such a faff to change a bit half way through a job that I usually compromise by trying to cut with only one.

Its a bunch of clever macro's and a matching screenset for Mach3 and two touch probes - one mobile for setting the initial work piece zero and a fixed plate for measuring tool length between changes. Dead easy to use and I have no issues with changing up to 7 bits in one job. The only inconvenience is have to change your bit but unless you get a megabucks auto changer and mega-mega bucks ATC spindle then this is as good as gets.

Link to the screenset:

The CNC Woodworker - Mach3 2010

Its about £13 but the best money I've spent on the CNC by far.

Here's a nice video that shows how it all works:

Mach3 2010 Screenset Tool Change - YouTube