Sunday, March 3, 2013

A shop is started

As expected the week was a shambles modelling wise. However Saturday rocked up and it was wet. So I went rummaging around the kits drawer and dug out a Dapol General Store kit and started cleaning the flash off it and started some painting on the sprue as it would be easier to do it on the sprue rather than when installed. These were left over night to dry. These will be the project for this week if I get time.

No Pi work unfortunately.

And on a personal note, my Dad passed away unexpectedly during Saturday night, he will be missed by all who knew him. I already am;-(

Sunday, February 24, 2013

Note to Self - Remember the resistor!

In between other duties I managed to put together the circuit described in the MERG journal but it didn't quite work correctly. As I did it on a breadboard instead of the stripboard as I wanted a temporary setup, possibly there was an incorrect wiring. Any way while I was mucking around with this I thought about checking the semaphore lamp after I had painted it black (as per quite a few prototype photos I found on the Net) to reduce the 'through plastic' brightness. I quickly wired up the 9V battery and the lamp glowed pretty brightly. A bit TOO brightly before dimming rapidly. What just happened I thought? Then it dawned on me, the RESISTOR! I forgot the resistor hence the extreme lighting. Damn! However it didn't completely stuff up the LED and there was a dim glow once I put a low resistor (68ohms) on the +ve wire. Not to worry as this was the experimental kit. I can always position the semaphore so that the lamp isn't seen.

Today I decided to connect the servo up to the MERG CBUS servo controller to see if it would work. Yep it did. With a bit of fine tuning with the help of the control software I think it works very well. I also connected up the lamp (with a resistor this time!) to video the movement with illumination. Below is the video.

This week not sure what I will do. Maybe get back to the Raspberry Pi as it has been nearly 3 months since I last mucked around with it (just before Christmas last year in fact!)

Sunday, February 17, 2013

Semaphore done..Now to automate

This week I was only able to finalise the semaphore. This entailed mostly painting in the wires. Today I bodgied up a jig from some ply offcuts for putting the semaphore in as well as holding the servo to automate the arm.

Below are the photos promised in the last post as well as what has been done this week.

This week I will probably only be doing the automation. Instead of the MERG module to automate, I might bung up on the breadboard a servo controller articulated in the latest MERG newsletter to see how it goes. If it doesn't the MERG module will be Plan B!


LED wires superglued along the post



Wires leaving the post and into the base hole


View of the wires in the base hole.
I could have used a smaller diameter drill in hindsight.


Close up view of the 'orange' LED from the front


View from the front. Note the red ball at top


View from the rear, wires just visible



View from read side.
Sorry the original is portrait but no idea why this
isn't!

 

Semaphore in temporary jig

Straight on view of servo in jig

Elevated view of servo in jig


 

 
 
 

 

 

 

Sunday, February 10, 2013

Semaphore kitbashing begun

This week in between other commitments I made a start on adding a working lamp to the Ratio semaphore. In hindsight and on future conversions I will do the following actions BEFORE assembling it! Retrofitting is a tad problematic.

I started by drilling out the lamp 'lens' straight through to the back end. Then taking the knife I started opening up the round drill hole into a rectangle to accept the SMD LED I had purchased from LedBaron. I was working with the magnifying glasses headband but after a while of being EXTREMELY careful with the razor sharp knife I was getting crosseyed trying to see what I was doing. There had to be another way? The next day I thought of using a rotary burr in my rotary tool. That night I checked what I had but the smallest burr I had was too big. I needed something 1mm or smaller in diameter to fit into the drilled out hole with sufficient room to carve out more material. The following day a bit of research on the Dremel page (my rotary tool isn't a Dremel but I was hoping for maybe a 'standard' amongst these tools?) and I found too bits that fitted the bill. Both were 0.8mm in diameter. One was a round burr and the other a straight sided cutter. The latter one was sounding really promising. I picked these up from Bunnings that night after one of my commitments. By the time I got home it was too late to do any modelling. The following night I was going to give it a whirl. When I got to it and went to insert the straight sided bit into the collet, the shaft was smaller than what the collet would accept. I rummaged amongst the bits tray but nothing smaller. I needed a 3/32" collet. Back to the Dremel site and they had such a beasty. I was able to pick up said collet from a hardware in the city on Friday. A quick check Friday night and the collet fitted the shaft and the bit went in perfectly. I'd had a few reds Friday evening so wasn't going to tempt fate on something so small, so I would have to wait until Saturday night. 

Saturday night came and so did a reasonably sober Greg ;-) With magnifying headband on, and the tool spinning away like a mad thing, it was time to make a start. Ever so carefully I sliced away plastic a fraction at a time and tried the LED fit bit by bit. I finally got to a point where the LED fitted into the space. A dabs of superglue and the LED was installed. I forgot to mention that earlier in the week I had applied some Tamiya Clear Orange onto the LED lens to imitate a incandescent lamp.

Tonight I temporarily wired up a 9V battery and resistor to the lamp and it worked. A bit too bright in my opinion so will need to tinker around with the resistor to really crank the brightness down to something more prototypical. I'm pretty sure that semaphore lamps were fairly dull in brightness rather than spotlight bright!

I had taken some photos to put up but just found that they were out of focus ever so slightly. I will retake this with another camera through the week and upload. Maybe I will complete the kitbash by gluing down the wires along the post, paint white and black where required, and glue the other fixtures (ladder, hoop, etc) to the post. Then it should be ready to connect to a servo and test this feature.

So that might be what the upcoming week will be about. Still no progress with the Pi and JMRI. Having too much fun with the modelling at the moment, which is the purpose of the hobby is it not?

Sunday, February 3, 2013

Not much this week

This week has been busy getting over the events of last weekend, otherwise known as The Big Blow ;-)

I did purchase some tins of Humbrol paint, epoxy filler (just in case of poor fitting), and some paint brushes ready for when I glue up the Dapol kits purchased awhile back.

I posted an earlier update to my written articles page, and that was about it.

Hopefully a better week this week re modelling or getting back to the Pi.

Friday, February 1, 2013

'Articles that I have written' page updated

I have been a bit tardy re this page and only just realised that I hadn't updated with respect to the article I wrote for Continental Modeller back in 2011 on installing a Loksound Select into a Trainorama NSWGR 44 Class!

I have updated it with a copy of the article, which looks so much better than my submitted notes to the magazine!

Sunday, January 27, 2013

Servo module works!

Not much this week. I was able to solder up the MERG CANACC8 module and do the necessary conversions to make it a CANSERVO8 server driver. After confirmation of a suspicion I had by a fellow MERG member here in Brisbane I had to make up the servo plug board from a piece of veroboard / stripboard. I did this today. I then connected it up to my experimental CBUS network and reprogrammed the PIC with a new driver file for the first time. I connected up a servo to the plugboard and was able to set the servo travel points. Yes I did every thing correctly and it works!

The other thing I did was raise a problem within the MERG Forum about the ability to broadcast the DCC stopping/braking bit in order to protect points/turnouts, similar to the commercial products available from www.dccbitswitch.com. It was a discussion point a number of years ago but didn't really get resolved with any standalone circuits at the time, however I have stirred up the hornets' nest! Lets see where this goes. The other option is to use JMRI to do the approriate monitoring of sensors and issue the relevant commands. Further research into this.

While I am typing this blog we here in the south east of Queensland are experiencing cyclonic winds and driving rain from ex Cyclone Oswald. Apparently going to get much worse tonight. I've spent the afternoon clearing yard drains and watching one of my trees slowly split down the middle of its trunk and have a very large branch perched precariously over my little garden shed. Hopefully it gradually gets closer to the ground and may just need a little encouragement to go the rest of the way.

STOP PRESS
As I was compiling the above blog late this afternoon (around 5:30pm) there was an ungodly crack from the back yard. I thought there goes the rest of the split trunk, but upon saying that to the missus she looked out the kitchen window and said "The whole tree has come down and hit the garden shed!" Out I went to survey the damage. What an impressive sight! Basically the centre of the tree trunk has exploded. Fortunately it fell into our yard and not into one of the neighbours' and caused damage. Unfortunately the 3x3m garden shed which I put up in 2011 will need to be replaced. Fortunately though it looks like the big shed survived without damage. Tomorrow will tell when I get out there with the bow saw and make start on the branch reduction in order to get to the door of the garden shed so as to clean it out! Hopefully the winds will have died down during the night and I can get on with it.

Earlier in the afternoon Lachlan and I put polytarps over our layouts in the big shed just in case the rain got up under the eaves.

So this week Lord knows now! Maybe I'll put together the servo mounting bracket and investigate further JMRI (semi) automation. Also the Raspberry Pi beckons but I am pretty sure I won't have time this week.