Latest progress on the Gooster - Page 14

GreatOldOne · #**261** 11th February 2010, 22:24

Well, I'd like to report success, but can't. Bah.

I've checked and triple checked everything on the board, but it only seems as if the first stage of the circuit is working (the first comparator). At and above the set threshold, I get a solid 9v on pin 1. On the second stage I get 8ish volts on pin 6 and milivolts on pin 5, resulting on nothing on pin 7. Nothing on 7 means no transistor switching the light on...

Can someone do a sanity check on this for me? Rob's off on holiday in austria now, so he's more interested in skiing than debugging a circuit via SMS.

Finalised circuit, which I know works from the prototype:

http://www.greatoldone.co.uk/Sportst...arningR1.4.bmp

Veroboard layout:

http://www.greatoldone.co.uk/Sportst...fuellayout.gif

Track brakes are denoted by the red squares. Ignore the markings on the transistor in the board layout - i've labeled the pins the wrong way round, but they are correct on the real thing.

Thanks,

Jason

Chris Cussen · #**262** 12th February 2010, 08:04

Jason, spent a few minutes looking at the laysout and can't see anything wrong.

Whats the voltages between R7 and D3, also D3 and R9 in both 'on' and 'off' states?

Just a thought have you put D3 in the right way round?

GreatOldOne · #**263** 12th February 2010, 08:19

I believe I have - but I'm begining to wonder if it's duff.

I'll have to measure the voltages again this afternoon.

MartinClan · #**264** 12th February 2010, 08:28

First thing to check on an PCB when it doesn't work are:

1. Dry joints? (How's your soldering Jason ;-) )
2. That the tracks are actually broken where they are supposed to be. If you just used a hobby knife it's easy to leave a small piece of copper in place.
3. Any accidental solder bridges

Robin

GreatOldOne · #**265** 12th February 2010, 08:42

My soldering is OK thank you. Much better now I have an iron that actually works.

http://www.maplin.co.uk/Module.aspx?ModuleNo=219133

All breaks have been done with a track cutter, and they look clean under a magnifying glass.

Solder bridges - it looks clean.... I did run a soldering 'pick' down the gaps between tracks and didn't meet anything but I'll double check.

MartinClan · #**266** 12th February 2010, 11:18

Quote:

Originally Posted by GreatOldOne

My soldering is OK thank you. Much better now I have an iron that actually works.

http://www.maplin.co.uk/Module.aspx?ModuleNo=219133

All breaks have been done with a track cutter, and they look clean under a magnifying glass.

Solder bridges - it looks clean.... I did run a soldering 'pick' down the gaps between tracks and didn't meet anything but I'll double check.

Ok - that's the obvious out of the way. It can now only be either a layout error or component failure. Components are pretty robust nowadays so I would double check the layout first.

Robin

GreatOldOne · #**267** 12th February 2010, 15:03

Quote:

Originally Posted by Chris Cussen

Jason, spent a few minutes looking at the laysout and can't see anything wrong.

Whats the voltages between R7 and D3, also D3 and R9 in both 'on' and 'off' states?

Just a thought have you put D3 in the right way round?

I have replaced D3, no change. Have changed orientation (from R7 to cathode to R7 to anode) no change... so put it back again

D3 -> R9 8.8V 'on', millivolts off

R7 -> D3 8.8v on, millivolts off

GreatOldOne · #**268** 12th February 2010, 15:42

Never mind, got it working now - when we did the vero-layout we missed a track break. I just discovered that there should be one row D, column 23. D3 was connected to R13 and the base of the transistor, which wasn't right at all!

Broke the track there, and lo and behold it all works. Yay!

Now to revise the diagram...

GreatOldOne · #**269** 12th February 2010, 19:17

Here's the circuit:

And here's it is in action

http://www.youtube.com/watch?v=oMLAEyGEKO8

Revised vero layout:

http://www.greatoldone.co.uk/Sportst...uellayout2.gif

GreatOldOne · #**270** 16th February 2010, 22:13

A busy evening!

All those pesky, sharp bolts covered up at the front:

Low fuel light mounted and wired in:

Momo hub trial fit:

Robin may have his bling steering wheel, but I have bling pedals:

MartinClan · #**271** 17th February 2010, 07:42

Jason

You will probably/possibly need to cover the lower spring plates. Mine failed on this. I used a universal U/J boot cut down. Also be carefull with the large lock nuts on the upper suspension arm. Mine failed even though they were covered. In the end I had to knock off the corners with a file before covering them with shrink. Spanner still fits!

Robin

GreatOldOne · #**272** 17th February 2010, 07:51

Thanks for the tips - I'll see if I can pick up some UJ boots. Any particular size?

MartinClan · #**273** 17th February 2010, 09:34

Quote:

Originally Posted by GreatOldOne

Thanks for the tips - I'll see if I can pick up some UJ boots. Any particular size?

I got mine from the local motor factor. They were only about a fiver as I remember (far cheaper than a re-test) It seemed to be one size fits all. They are made of some very strange rubber with elastic properties so you can stretch them to fit any UJ (Or Marlin spring).

You need to cover the sharp edge of the spring plate that faces down which is just about contactable by the test sphere if you have a zealous tester....

Robin

GreatOldOne · #**274** 17th February 2010, 12:24

Just called my local motor factor - he has some in, so I'll be picking a pair up on the way home from work.

Chris Cussen · #**275** 17th February 2010, 13:10

When fitting the flexible UJ boots (not that you are, but I used them to replace the boots on the driveshafts of the Cabrio) you turn them inside out and slide them over a very large greased cone.

It makes your eyes water just to think about it.

GreatOldOne · #**276** 21st February 2010, 20:46

Not one, Not two but three updates to my build website!

http://www.greatoldone.co.uk/Gooster...%26_Belts.html
http://www.greatoldone.co.uk/Gooster...Gas_Light.html
http://www.greatoldone.co.uk/Gooster...uel_Light.html

The two blog entries have nothing I haven't posted here already, but I have added a new page devoted to the low fuel light circuitry, with all of Rob's calculations and high res copies of the circuit and the veroboard layout if you want them.

The other thing is I've re-enabled commenting on the site - I couldn't get it working on previous version of iWeb so i used a third party ad on that wasn't that great (and has now given up the ghost altogether) - but I have got the in-built commenting system on iWeb 09 working now. So you can leave me rude messages on my site as well as here!

GreatOldOne · #**277** 13th April 2010, 07:34

I fitted the windscreen yesterday. What a pain in the arse that was!

I follwed the instructions to the letter. Measured three times before cutting the slots. Got them cut out, had a cup of tea and then it dawned on me.

I'M SUPPOSED TO BLOODY MEASURE FROM THE BACK OF THE SCUTTLE, NOT THE FRONT!!!

So I have some filling to do now that I have the screen in the right place. I really am a dullard at times

GreatOldOne · #**278** 13th April 2010, 11:57

Apart from the extra ventilation, another thing is bugging me. I have the screen centered, square and level, and the fit of the pedestal / ali filler piece with the rubber is spot on

However, it looks like one side is further over than the other, as one wing mirror is closer to the screen pillar than the other. Measuring to check that both mirrors are in the same place shows that they are - so what gives?

It fits the body work perfectly, and looks central. I have had to pack the legs with washers as per the instructions, and I just assumed that this was due to the 'handbuilt nature' of the scuttle...

I'll post some pics tonight to show you what I mean.

MartinClan · #**279** 13th April 2010, 19:37

Quote:

Originally Posted by GreatOldOne

Apart from the extra ventilation, another thing is bugging me. I have the screen centered, square and level, and the fit of the pedestal / ali filler piece with the rubber is spot on

However, it looks like one side is further over than the other, as one wing mirror is closer to the screen pillar than the other. Measuring to check that both mirrors are in the same place shows that they are - so what gives?

It fits the body work perfectly, and looks central. I have had to pack the legs with washers as per the instructions, and I just assumed that this was due to the 'handbuilt nature' of the scuttle...

I'll post some pics tonight to show you what I mean.

Use the Upol filler that contains fiberglass strands. It is far stronger than straight filler.

Use the Marlin measurements with some discretion. Due to the 'handbuilt nature' they are only a first estimate.

I didn't ever check if mine was central but id you have the same number of packing washers each side it should be about right When I stripped my car to have the panels painted howeve I noticed that the supports for the scuttle bend easily.....

I had to trim the aly filler panel considerably to make it fit. It looked like a 5 year old had cut it out!

Just keep at it and remember to measure lots of times before you v
cut. You will get there in the end.

Robin

MartinClan · #**280** 13th April 2010, 20:39

Quote:

Originally Posted by GreatOldOne

However, it looks like one side is further over than the other, as one wing mirror is closer to the screen pillar than the other. Measuring to check that both mirrors are in the same place shows that they are - so what gives?

How much are we talking about? I just checked mine and it is OK side to side but about 3mm out front to back. It dosent show...

Robin