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Re: Brimsdown-The last grand project.

Posted: Wed Sep 23, 2020 5:47 pm
by trustytrev
Is it possible to get a diamond cutting disk for longer life with these machines?
trustytrev. :)

Re: Brimsdown-The last grand project.

Posted: Wed Sep 23, 2020 9:43 pm
by Philip Hall
A diamond disc is available and I have one to try one day. I was recommended to try this ‘special steel‘ blade by the supplier and it has been pretty good. It may be that the diamond disc gives a slightly cleaner cut but as this works well still I’m not going to make a change until the blade is completely worn out. It’s easy to change but a bit of a fiddle in a small space.

I don’t know whether a diamond blade will last longer (yet!) If it’s of interest I can photograph the two blades.


Re: Brimsdown-The last grand project.

Posted: Thu Sep 24, 2020 8:08 am
by Terry Bendall
Philip Hall wrote:The only problem is that it doesn’t go all the way to the table bed when cutting such a thin strip,

That is probably the best that can be done Philip and as long as the teeth are covered that should be sufficient protection. The normal practice with larger saws is that the guard, known as the crown guard, is "as close as is practicable" to the top surface of the material being cut. In practice about 10mm or a a bit less on the basis that your fingers are thicker than 10mm.

Philip Hall wrote:I use thick coffee stirrers to push the PCB though and against the fence as well as to hold down it down as the bits get smaller.

An ideal solution and correct practice.

Terry Bendall

Re: Brimsdown-The last grand project.

Posted: Tue Sep 29, 2020 3:21 pm
by Tony Wilkins
After concentrating on getting the relay cards done, because they were simpler, (relatively speaking) I have now gone back to the display cards, however what should have been relatively straight forward, has turned into something of a saga. One of the last pictures I posted was this one.

The strip-board on the right was the last one I then had (since used) so ordered some more. When the order arrived, including other components I had ordered, the strip-boards turned out to be the wrong size, only half as long (like those in the middle) and of little use to me. After checking I discovered that the the wrong item had been put to stock by the supplier so needed to be returned for a refund. This presented a conundrum. If I reordered, there was a good chance of a repeat performance, or did I wait and hope they would sort their stock out first? The problem was that I had reached a stage where I couldn't make further progress without more strip-board.
I decided to try an alternate supplier I sometimes use and found a suitable, but longer, alternative. These were ordered and duly arrived the next day.
I was therefore able to make the next display card.

There are a lot more components on this one that the first one shown above.
There are other differences. The top PCB has the display modules as part of the build (for testing purposes, it will need to be separated later anyway) whereas for the latter ones I made them separately, this is where the last piece of strip-board went.
Despite doing this, the resulting PCB is still longer than the one above after shortening it, meaning that I would not have been able to fit everything needed onto the PCBs I originally ordered, so it is perhaps serendipitous that I ended up with the longer ones. I only hope none of the other two display cards are any longer as I have reached the maximum length I can sensibly fit across the width of the control panel.

At the top is a full length piece of strip-board. At this length it is a bit unwieldy for wiring, but not knowing the required length, I left as is until I had finalised the component layout.
The new card at the bottom has its display PCB to the right.
The plan is to link them with some pieces of flat flexi cable that I have on order, the problem here is they are currently out of stock and not due in till mid November. Until then I cannot link the two together and test them out. I am loath to do so temporarily as strip-board does not take kindly to repeated soldering and unsoldering of components, so I will just have to bide my time. It aint as though there aren't other things to get on with in the meantime.

Re: Brimsdown-The last grand project.

Posted: Tue Oct 13, 2020 11:51 am
by Tony Wilkins
Well all the PCBs are now done and here is the full set (minus display boards) laid out in the base of the control panel.
This may not be the final arrangement as fixings for the front panel have yet to be finalised.

Some weeks back I ordered the Aluminium sheet I would need for the front panels. I finally got round to opening the package yesterday. The supplier specified their cutting tolerances as +2 -0mm, so I reduced my specified width of the side pieces by 1mm just in case. The sheets are all cut to -0mm so I have two small gaps to live with now. Perhaps I should have just gone for the sizes I wanted in the first place, but I didn't want to be faced with lots of filing in order to get things to fit. There is going to be enough of that to do anyway with the display cutouts etc.


Re: Brimsdown-The last grand project.

Posted: Thu Oct 15, 2020 12:03 pm
by Tony Wilkins
So here is the first fit of the main aluminium front plates (ignoring the trial fit which showed some minor adjustments were required).
The rather attractive blue colour is the protective plastic film as supplied.

After some debate I decided to hinge the front plate for access. This in itself created some issues with fitting and alignment.
It has meant repositioning some of the circuit boards. The wooden blocks will give additional support for the panel when down.

The paper printout gives a good impression of the intended appearance of this part of the control panel.

The angled panel at the back will house the numerical LED displays for the roads selected. The next job will be to cut the holes to mount these as they need to line up accurately with the display driver PCBs to be mounted on the base. The back plate will have to be removed for this.


Re: Brimsdown-The last grand project.

Posted: Sat Oct 17, 2020 4:55 pm
by Tony Wilkins
Well here is the back plate with the holes cut and three of the numerical LED modules fitted. The forth one is still attached to the rest of the display driver board and I am a bit loath to detach it at the moment as the connecting cables I have on order are currently unavailable for another month or so.

Re: Brimsdown-The last grand project.

Posted: Wed Oct 28, 2020 11:11 pm
by Tony Wilkins
Well I finally took the plunge and printed the panel on my Vinyl sheets with mixed success. It was every bit as trying as I thought it might be. Due to the extra thickness over paper, it has a tendency to jam in the mechanism. This was the second attempt. This is actually two sheets of A3 joined together on the backing paper with sellotape.

I used this to position and mark the placement of all the required holes in the front panel. To prevent it moving during the process, I used two strips of masking tape at either end to hold it in place. This did not turn out to be one of my better ideas as when I later attempted to remove the masking tape from the film it left sticky residues behind, which rather negated the reason for using masking tape in the first place. Attempts to remove this with various solvents failed but did succeed in smearing some of the printed ink thus ruining the vinyl printout. Attempts to print off another were of varying quality, but I eventually managed to produce two halves that were, I hoped, usable.
However, I pressed on and drilled all the holes that I had by now marked with a center punch.
I thought I had taken a picture of the plate with all the holes drilled, but it was not in the camera.
Choosing the best two vinyl sheets I then attempted to stick these onto the surface of the front panel correctly aligned. I don't know what the best technique for using large self adhesive vinyl sheets is, but I clearly didn't have it. The result isn't what I would have hoped for but I decided to live with it, at least for the moment. When I had the Aluminium sheets cut, I ordered two of everything just in case, so I do have a second front plate spare.
I then spent a happy evening fitting all the switches and this is the result.
It's beginning to come together and is going to be quite impressive. At least, I think so.

The underside looks like so.

There is going to be a lot of wiring required. One thing I made sure of was that all the push button switches were the same way round as this means the same tags are wired up on each switch, so this only has to be tested once with a meter.

Meanwhile, when assembling the storage yard baseboards post wiring, I discovered that some of the baseboard joints needed attention and one in particular was a real doorstep. I separated the baseboards to investigate and this is what I discovered.

The bottom of the Sundeala board had de-laminated and is not the first time this has happened during this construction. Sundeala ain't what it used to be and I have had second thoughts about making that choice in the light of experience, however, there is no going back now. After cleaning out the split with a thin saw blade, as much wood glue as possible was inserted with the aid of a spatula. the area was then firmly clamped and left to set overnight.

The result?
The rail direction of the step was less but reversed. This was dealt with by raising the rail ends on extra solder.

Re: Brimsdown-The last grand project.

Posted: Mon Nov 02, 2020 1:48 pm
by triumph3
Having visited Tony ( socially distanced) on Friday I was very impressed with the scale of the layout that he is building. It’s one thing to see a track plan, but to see it in the flesh makes you realise how big it is. The layout is larger than most clubs or groups would attempt to build, so Tony deserves huge credit for the progress to date.


Re: Brimsdown-The last grand project.

Posted: Thu Nov 26, 2020 11:02 pm
by Tony Wilkins
Whilst waiting for the flexi cables to arrive, I had intended to get on with some other jobs pending. Things didn't quite work out that way, but I made good use of the time in other ways. My main computer has been acting up for a while now and has recently taken to crashing randomly. Investigation pointed to a faulty memory module and a replacement was sought. Due to the age of the machine new parts weren't an option, but an online search proved fruitful and one was ordered and when installed I am glad to say cured the problem. Until this was done, I was loath to alter files and save them in case they became corrupted, or worse.

The cables finally turned up a few days earlier than predicted, so after finishing the current job, I was able to get back to some wiring.
The flexi cables were soldered to the LED module PCBs and in turn connected to their driver board via header socket strip for testing.


All four LED modules could then be installed in the rear panel and the jumper cables can be seen hanging down below the panel.
The wired connector was the temporary lash up to test the first display board. This will have to be disconnected and done properly.

The next job was to wire the connectors for the driver boards ready for installation. Here is the first one to be done.
The three single colour wires Grey, Black and White are power rails and the multi colour wires are matched to those on their respective tags, at least in theory.

Re: Brimsdown-The last grand project.

Posted: Fri Nov 27, 2020 1:13 pm
by Tony Wilkins
I say in theory because the probability of errors always exists.

I cut 8 pieces of strip board for the edge connectors, but owing to two of the display cards being longer than expected, I was forced to mount these edge connectors vertical instead of horizontal as intended and some angle mounting brackets were fabricated. The height then becomes an issue as there are switches mounted on the front panel above and I had to reduce the height by two rows of holes. However I did not discover this until after I had wired the first edge connector. So off came the wires and out came the saw. Then it had to be rewired. It was not until I wired this in that I discovered I had used a White / Orange wire instead of an Orange /White wire as can be seen on Tag 52. Annoying, but I will live with it.
The other Display card edge connectors were wired up in turn. The central extra tag strip is for power supply distribution.


Next come the Relay cards.

Unlike the display cards that only have inputs, the Relay cards have both inputs and outputs.
The outputs go to the Tag strips, but the inputs go to the control panel, which since I wanted the ability to work on as a separate item, means further connectors. My options are limited, but a solution has been devised and parts ordered.

Re: Brimsdown-The last grand project.

Posted: Sun Nov 29, 2020 1:06 pm
by Tony Wilkins
My connectors arrived later that afternoon and were soon soldered into place.

Saturday was spent wiring the relay card connectors to the tag strips.
Here is the first one done.

By 11pm all were in place.

This just leaves the front panel to wire and fit, then a thorough testing session will commence to find the faults.

Re: Brimsdown-The last grand project.

Posted: Sun Nov 29, 2020 10:48 pm
by Dave Holt
It all looks quite mind boggling to me.
Hope it all works with not too many faults to resolve.

Re: Brimsdown-The last grand project.

Posted: Mon Nov 30, 2020 1:37 am
by DougN
Seriously impressed Tony. My next layout i want to be as tidy as your control board above! Avoiding all the flying leads and so on. Your tag strip across the bottom is an idea that I had through about and I think I will adopt! :thumb

Re: Brimsdown-The last grand project.

Posted: Mon Nov 30, 2020 12:51 pm
by Tony Wilkins
Dave Holt wrote:Tony,
It all looks quite mind boggling to me.
Hope it all works with not too many faults to resolve.

Hi Dave.
I will be pleasantly suprised if there are no errors in something this complex, especially as I have not been able to fully test some of the sub modules before final assembly.
I have been following your Royal Scot thread where it is my turn to have my mind boggled! Your attention to detail is something else and you have my greatest respect.

Re: Brimsdown-The last grand project.

Posted: Mon Nov 30, 2020 1:03 pm
by Tony Wilkins
DougN wrote:Seriously impressed Tony. My next layout i want to be as tidy as your control board above! Avoiding all the flying leads and so on. Your tag strip across the bottom is an idea that I had through about and I think I will adopt! :thumb

Hi Doug.
Using tag strips is a good discipline I think. They encourage documentation of the connections, a typical example attached
Yard Up 1.DOC
(16 KiB) Downloaded 33 times

and they can be a great aid when fault finding as there is something to hook the meter onto.
Most of the layouts I have been involved with were done this way. Yes, it is more work, but I think it more than worthwhile.