Laser tool setter for The Shiz!

Wow, lasers in da shop?

For a few years now, I've been using a Renishaw TS27R tool setter for touching off tools in The Shiz. 

This is a massive timesaver and allows pretty accurate tool length measurement, which is rather important if you want to be able to change tools in the middle of a job without incurring errors due to a change in tool length - touching off against a fag paper or an accurate gauge (eg a 10mm broken end mill) is OK but takes a bit more messing about.

In Centroid CNC12, there's a pretty nifty extension called CHIPS that was developed by "Swissi" (Roland Kunz) that automates the process of measuring tool offsets and saving them to the tool library. In conjunction with a tool setting probe such as the TS27R, the process is wonderfully simple and quick.

One drawback of CHIPS to date has been that it only measured tool length offsets, not tool radius offsets (due to wear, tolerance and runout). However, a recent update has extended the CHIPS capability to include automatic tool radius offset measurement. This is generally done with a rotating tool, as many (most) tools have multiple flutes or inserts. Although the TS27R is intended to be capable of this kind of operation, it requires the CNC controller to have that functionality. Now it seems we have that available in the latest version of CHIPS when combined with the massive update of CNC12 to version 5.4.

Enough. Show me the lasers.

Rather than require an exotic (= expensive) toolsetter such as the TS27R, the recommended solution developed by Uwe (another CNC12 user / developer) is a "laser fork" sensor. This uses a laser beam to detect the tool, rather than contact with a setter. 

I have to say, approaching the TS27R with a spinning face mill would be a bit of an act of faith. Spinning it within a reasonably large (80mm) gap feels a little less of a buttck clencher, so there may be a lot to be said for this approach.

Uwe's solution was one of these Wenglor "laser fork" sensors.

It's pretty straightforward - once the beam is interrupted, the output goes high. The power supply voltage is 10 - 30V, ie compatible with the 24V used by Acorn's inputs. There is a slight compatibility issue, namely that the Acorn expects a tool setter to be normally low (normally closed to ground), going open circuit (pulled high by Acorn's input) when an interruption is seen.

Got a couple of these from German ebay, with 30mm and 80mm widths.

My machine is already set up for the TS27R and I'm loath to change the setup radically at this stage. I'd like the additional radius offset measurement features of the new CHIPS release, so perhaps I can configure the fork to work in the same way, so that I can simply swap them over as required.

Uwe's solution is to fit a standalone Chinesium "PNP to NPN converter". This is an opto isolator with a normally closed / low output that goes open circuit when presented with a high signal at its input. That's a bit of a PITA, so perhaps I can do something different and possibly even better.

NP to NPN converter:

What's needed is a normally on NPN transistor that is turned off when the laser fork output goes high. That requires 2 switches that could be either NPN or N channel. I have a bag of ZTX451 transistors that should do the trick. These are from Diodes Inc, which used to be Zetex (and before that, Ferranti), with a 60V rating and a decent current gain.

I'm going to make a "rat's nest" assembly, rather than fuck about with strip boards or even PCBs. Here's the guts of it:

This will sit inside the control cabinet at the end of a shielded flex cable.

At the other end, I've grafted a Chinesium connector that mates with the laser fork. This seems to be a common connector that I've not encountered before, called an "M8" connector, due to having an M8 x 1mm thread. This one's a 3 way version. Of course, the colours are all to cock. I figured out that the ground connection is yellow, the +10-30V is red and the output is black. I will correct that by the time the wiring emerges in the control cabinet.

With some heatshrink to protect each wire and a piece of adhesive lined heatshrink over the whole thing, it should hopefully be fluid proof like the IP67 sensor itself.

As the rat's nest isn't going to be very robust against shorting itself out internally, some rapid setting epoxy adhesive should do the trick. Obvs I tested that it worked before slathering this stuff on, as it's a one time event. If it doesn't work under the epoxy, I will have to start all over again:

And here it is finally, with the smaller (30mm) fork for testing. The final installation will use the 80mm fork.

Does it work, Fatty?

Yes it does - TFFT. Next steps will be to configure the tool setting function in CHIPs. I've got CNC12 5.4 working after the big update but CHIPS wanted a configuration setup focused on its own features, which I chose to leave until later.

First, I'll check that the TS27R works as expected, then fit an additional cable gland on the control cabinet for the laser fork. That will be the next workshop session...

Brown stuff finished - with costs

Phew. 

Got the rest of the wood. What have I let myself in for?

Felt as if it took half an hour to mark up all the bundles ready for cutting into 3. Then the best part of an hour to do the actual chopping.

Obvs the pillars are all at different positions, so the fence sections are of different widths. In order to get the 150mm (aka 6") slats evenly spaced with roughly 75mm (aka 3") gaps, clearly the only answer was to create a spreadsheet.

Knowing that each slat is 150mm and the target gap is around 75mm, I calculated the number of slat/gap pairs would fit in the space available, then rounded off the resulting number to the nearest integer number. Then I calculated the gap that would result from that number of 150mm slats evenly spaced, then finally the distance of the edge of each slat from the starting position.

I then measured the widths of each of the 8 sections, dialed it into the spreadsheet and printed out the table of coordinates. Then it another apparent half hour to mark out the positions of the slats on masking tape stuck on the horizontals. 

With 2 decking screws per slat, I calculated that I'd need 256 screws. The box of Spax stainless steel decking screws contained a nominal 250 screws. I guessed they would need to guarantee at least 250 would be shipped - but how many extras would they give me? Answer - 5, so I only needed to find a single extra screw to finish the job. The screw gods smiled on me.

Job done. Yes, I had a few left over. The Stupid Fat Bloke had a rush of blood at the timber merchant and brought home too many. And natch I didn't count them up before chopping them up, so I can't take the extras back. Ho hum.

And the cost, overlooking my free labour and not including the surplus planks:

So my estimate of £500 looks eerily on the money.

Job done.

More brown stuff

There's a reason I've not been in the workshop doing proper workshop things of late - and that's due to the backlog of jobs I need to attend to around the house finally. The bad news is that much of it involves The Brown Stuff, rather than metal. Can't be helped I'm afraid.

Here's the latest self-imposed task. Rotten fence beside the driveway. So rotten that it was falling apart and threatening the cars. Off it comes...

Down to Wickes for some treated 3"x2" for the horizontals and some treated rough sawn 6"x1" planks for the vertical slats.

Each 2.4m length of plank cut down into 80cm long slats, then the ends treated.

Horizontals fitted into the pillars.

And mortared up with red mortar.

Next weekend (today), over to Wickes for more timber. The Money Pit can at least lug some timber, allowing me to select the pieces I want rather than play the lottery by ordering it for home delivery. These are 2.4m long.

What have I let myself in for? And this lot on top of the previous trial run will only take me to about 60% complete. Oof.

And..... on with the first set of slats, fitted both sides (staggered) to give some privacy but also allow the wind to blow through.

This buddleia magiced itself up out of thin air a few years ago (perhaps 5?) and has had a good life but it's time to go before it topples the adjacent pillar over.

There. Gone. And the holes for the horizontals are cleared out, ready for their replacements. I'm bracing myself for another session tomorrow, cutting them to size and mortaring them in position, then cutting the slats and treating the ends prior to fitting.

And yes, the gates need to be wire brushed, primed and painted. We have a load of the blue paint that was used on the new front door, so the colours should match.

Oh yes, plenty more work to be done.....

Wifi booster?

What?

I've been suffering from weak wifi coverage in the workshop from the outset. The problem is that when we designed this whole extension to the house, it made sense to have it built so that it met all the building regs ("code" in the US and Canada), so that it might be worth more than it cost to build. 

I did most of the "second fix" myself, namely the wiring, plumbing, heating, painting, lighting etc, so saved a fair bit of the cost. Including the kitchen / dining room extension (aka "sun lounge"), utility room and toilet, it cost something like £50-60k plus several years of my life. Obvs I got the electrical installation tested and certified by a qualified electrician and the building work was inspected and signed off by the local building control office.

The upshot is that the walls between the workshop and the existing house are cavity wall construction (ie 2 walls, separated by a cavity filled with insulation). While this is great for noise and thermal insulation, it's also wonderfully effective at blocking wifi. Even the roller door is aluminium. I've got a "TP-Link Deco M9 Plus"mesh router system running the whole house but naturally it barely makes it through here. 

I suspect the bottom line is that most of these routers are designed for the US market where most houses are constructed mainly from wood ie relatively permeable to wifi signals.

I even tried a Powerline extender at one point but it barely worked. I think I can blame the wiring for that, as I have an armoured steel cable feeding a dedicated consumer unit in the workshop. This makes the route between the main router and the workshop sockets rather tortuous / torturous (take your pick).

What to do? In a last gasp attempt at using technology, I bought one of these supeydupey Wifi 6 range extender things.

Did that help? Did it shite. The problem remains the same ie maintaining contact with the mothership in the house.

Plan B, then:

I've considered this before but never quite got round to it - fit an external aerial / antenna outside the workshop where it can be pretty much guaranteed line of sight to the main Deco router.

To my limited recollection, these wifi routers typically have an array of 2 or more aerials that connect to the main PCBA by means of small "UFL" (UHF) connectors. If I can unplug one of those and replace it with a length of coax leading to an external, wall mounted twig, surely this should do the business.

Found a handy teardown report on these Deco M9 Plus things and it showed how to open them up. Sure enough, there are 6 such PCB aerials distributed around the circumference of the PCBA. So let's get an aerial and see if it works....

Bought one of these Chinesium twigs:

Managed to thread the coax cable through the roller door frame:

The Deco unit is disembowelled while I test it out. 

Works nicely, so let's tidy it up by mounting the SMA plug on the top cover. 

This holder thingy keeps the wiring tidy and provides a means of mounting the Deco using the mains plug and PSU.

A suitably positioned hole allows the SMA socket to be mounted on the cover.

Here it is in its final embodiment.

And showing a reasonable connection back to the main Deco in the house.

The connection to the Nucbox in the workshop isn't bad now.

We'll call that done. Hopefully my Samsung work laptop will also work - it's the most profoundly deaf of the various wifi devices there.

Stained glass window soldering

Here's our inner front door. It's probably one of the few original doors in the house and has an original stained glass panel. Not surprisingly, the lead joints have fatigued after 93 years of the door being slammed several times a day. The middle of the panel flaps a good half inch when you waggle the door open and shut.

I couldn't stop The Stupid Fat Bloke from removing it and starting to remove the panel. He'd whipped the door off and made a start before I knew what he was up to. Oh well...

Got the panel out without it completely disintegrating:

I previously bought a fine Chinesium soldering iron for the purpose of resoldering the damaged joint. It has a massive boss end tip and is rated at a Chinese 200W. I have to say it didn't fuck about but after 10 mins or so, the temp had risen way above the recommended setting of ~350-380C, so that the lead melted almost instantly and left a gaping hole. Not ideal.

So, out with the Pace iron. It's only rated at 80W but has thermostatic control.

Some of the joints were royally buggered.

There was even one that the original craftsman had missed:

If you look closely you can see the 2 fractures in this joint:

There. Both sides fully resoldered and ready to go back in when the door has been stripped and refinished using Osmo Polyx Tint 3072.

Job done.