Another Method for making a ‘Chuff Cam’

Sometime ago I did a post on how I make ‘chuff cams’ for model steam locomotives using Super Glue (ACC).

Erik Bennett sent me an email recently with his method so I asked him if he minded if I posted on the blog. As a result with Erik’s agreement here is his method for setting up a ‘chuff cam’ on a model steam locomotive.

Hi Ray,

I’ve put chuff cams in a number of locos, previously using a piece of 35mm film negative, cut to shape and superglued to the back of the wheel.

I saw your blog a few months ago where you described the technique of painting superglue on the back of the wheel.

Knowing how hard superglue is when it sets, I thought it a great technique and decided to try it on my next loco.

Well, I just finished a loco and it works great.

So, thank you for posting your superglue technique.

For info, I modified your method slightly and offer it here as an additional method:

I found it a bit tricky to get a clean edge when free-painting using the pencil mark method.

So I cleaned the superglue off my early attempts and cut 4 identical strips of adhesive tape.

The strips were about 3/4 the radius of the wheel in length and wide enough so that four strips gave four equal make & break sequences.

I actually used Tamiya painting tape and put 4 bits on top of each other on a pane of glass, then did my cuts.

Bearing in mind that the chuff sound is made on the break (not the make), I marked on the wheel where the break should be in relation to the pickup contact when the rods are TDC (Top Dead Centre - RP) as the wheel rotates forward.

I positioned the first strip radially outwards so its trailing edge was aligned with this mark. The longish length of tape makes it easy to align radially.

I then positioned the other three equidistant around the wheel.

Then I painted superglue as evenly as I could in the bare spaces between the strips.

I let it dry for a day, removed the tape and gently smoothed any raised edge where the superglue had interfaced with the tape.

I ended up with 4 nice tough break surfaces!  And nice chuff sounds when the engine runs, synchronised with the rods.

So thanks once again; your method is much easier than the 35mm film.

 

Best regards,

Erik

Thank you Erik it is nice to get feedback about the blog and I am glad it got you thinking to come up with this more sophisticated version of the ‘chuff cam’.

7mm Scale Clearance Posts with Lamps

New Addition to the 7mm Scale Range

7mm Scale Clearance Posts with Lamps have been added to my Signals Branch Shapeways Shop since my last post, these are printed in Frosted Ultra Detail material and have been designed so that a 3mm LED can be inserted into the bottom of the baseboard mounting to have them lit.



View from below

3D drawing

Shapeways Frosted Ultra Detail Render

Of course these clearance posts with lamps are also available in HO on my Signals Branch Shapeways Shop.

Sorry for these types of posts, the 3D designing and printing has kept me sane over the last 12 months.

I will get back to the usual type of posts soon.

Back again after my longest break in posts

I felt I had to take a break from posting on the blog so please accept my apologies. At home here we are coming up to 12 months since we lost our lovely daughter Kirsty and the last few months have been difficult for Chris, Bonnie, her boys and myself.

I have tried to keep my interest in the hobby going more as a distraction than anything else, the layout has had nothing done to it since March last year, but it will return to the blog.

So inevitably I have been working on some 3D printing stuff as the mental exercise works well.

As mentioned in previous posts I was working on several projects that have now been made available on my Signals Branch Shapeways Shop.

With apologies for the repeated photos, these items are:

• NSWGR A Frames in HO and 7mm Scales (point rodding supports from lever frames).

7mm Scale A Frames (HO track behind)



HO A Frames - Still to be glued in place

• A range of Fine Detail HO signals in Frosted Ultra Detail (FUD) and so far I have single arm 16ft - 30 inch arm, 18ft - 30 inch arm, 23ft - 36 inch arm and 27ft - 39 inch arm signals, more signals and arm types will follow as I find the time to draw them up.

HO A Frames and high resolution FUD signal

• NSWGR 1924 Derail in HO, a track arrangement at the end of a siding where it meets a main line to prevent wagons from fouling the main line. The plan below is also available on my Signals Branch Blog in the Links section.

• NSWGR 1936 Catch Point in HO, a more complicated version of the Derail with a moveable rail and a catch point indicator (a ground signal). The plan below is also available on my Signals Branch Blog in the Links section.

• NSWGR Catch Point Indicator in HO and 7mm Scale that can be made to work from a rod to the moving catch point blade.

7mm Scale Pilot Model Test Print

• A range of 7mm Scale signals in White Strong and Flexible (WSF) and so far I have single arm 16ft - 30 inch arm, 18ft - 30 inch arm, 23ft - 36 inch arm and 27ft - 39 inch arm signals, more signals and arm types will follow as I find the time to draw them up.

'Proof of Concept' trial 7mm Scale 23ft signal

The above 7mm Scale signal  doesn't represent what is available as more detail has been added along with a couple of minor corrections.


More information and instructions for the above items can be found at my Signals Branch Blog.


Now a Possible Challenge for the N Scale Modellers

I have recently received a 3D print of a NSWGR 23ft signal as a 'Proof of Concept' trial.

The signal would be a challenge to assemble as it requires drilling some holes with a 0.3mm drill bit (smallest drill bit I know of) and using 0.008" (0.2mm) phosphor bronze wire from Tichy Train Group (Part #1100 - 10 lengths) as the operating wire. The modeller will have to have a steady hand and good eye sight.

One thing became obvious and that is that the counter weight lever on the post is probably going to have to be static with the operating wire coming up from the mechanism below to the arm. The reason for this is that holes to be drilled in the lever for the pivot and operating wires would mean that the lever would have be thickened too much and would look very wrong. The amount of movement it would go through would be quite small and also the holes being 0.3mm and the operating wire being 0.2mm the slop could cause operating difficulties. I am not sure how this can be got around for bracket signals, I will have to think about that.

The trial signal arm is pivoting on a brass pin and the usual method of printing the pivot shaft with the signal was not good as the shaft broke easily, more to think about.

Of course the signal could be made non-working.

Anyway at the moment the possibility of adding N Scale signals to my Signals Branch Shop at Shapeways is a reasonable bet unless I run into some problem I can't solve.

Now just to show that it can be made to work here is a video:

I hope that this post has been of some interest.

Merry Christmas and a Catch Up

Chris and I would like to wish you all a Merry Christmas and hope you have an enjoyable time with your loved ones.

Catch Up

As you will have noticed I have been tardy with my blog posts recently. I have been a bit disinterested in the layout due to the approach of Christmas, remembering back to the good times last year before 2015. I am still trying to keep myself distracted with new projects and have been finding it difficult to continue working on projects in hand. This includes the Werris Creek station building, the subject of my last post, nothing has happened.

Chris and I went to the Branchline Modellers Forum in Coffs Harbour and thoroughly enjoyed ourselves but of course it was an escape from reality, anyway enough of that.

I have been working on several 3D projects including the catch points and indicators; I have stalled here while I work out how to increase the throw from about 75 degrees to 90 degrees to spin the square indicator fully. I have had pilot versions printed in both HO and 7mm Scale (very nice in 7mm, very small in HO).

NSWGR A Frames

I have drawn up and had printed some NSWGR A Frames; now these are the stands that support and guide the point rodding from a lever frame to one or more points.

I have taken the usual couple of photos but as the prints are in the translucent Frosted Ultra Detail material from Shapeways they are difficult to get a clear image of the surface detail. Here are photos of a double A Frame in HO and a single A Frame in 7mm scale. The A Frames are still on the sprue and the point rodding is 0.5mm X 0.5mm Evergreen shaped strip for HO and a 1mm X 1mm Evergreen shaped strip for 7mm Scale.

I have also included a render from the computer so that the detail can be more readily seen. Once the frames are painted the detail will be more visible (done now - see below).

HO Scale A Frames

7mm Scale A Frames

Computer Render of banks of four A Frames

I am quite happy with these and have put the HO and 7mm Scale versions on my Shapeways shop.

See my previous blog post for details of some Shapeways money saving offers over the next week.

The 1mm strip fits nicely through the 7mm Scale A Frame but the 0.5mm strip is a neat fit.

It is best to 'dry' fit the rods while the A Frames are on the sprue, then cut the A Frames away, space the A Frames on the rod(s), glue then spray paint the whole structure. Also It would be best to only make up lengths as long as the Evergreen strip, any longer and they become unwieldy when spray painting and handling them. Of course the lengths can be joined/glued together on the layout.

 

I have drawn up A Frames in 1, 2, 3, 4, 5, 6, 7 and 8 wide and they are available as a sprue of 20.

Next, I have to start drawing up the bell cranks, compensating cranks and other bits that operate the points. I have some photos and basic dimensions so only have to find the time which might not be until after Christmas.

 

While at the Branchline Forum we went to Dorrigo on the Sunday and I managed to measure the spacing of the A Frames from a lever frame to the first point near the Dorrigo Home Signal. The spacing was unusual being 7 feet give or take a few inches. The point rods were bolted together and the joints were spaced between the A frames, the rods being 14 feet long. Now these seem to be odd dimensions and all I could think of was that the rods would be carried in an S truck with the space beyond their ends in the S truck being taken up with the A Frames themselves. Who knows?

 

Here are photos of the HO and 7mm Scale A Frames. Note that the 7mm ones are just sitting next to some HO track on my layout.
 

Painted HO double A Frames with rods (not glued in place yet)

Painted 7mm Scale single A Frames with rods - Note: HO track behind

In the HO photo the observant may have noticed the wheel fitting on the bottom of the signal post, here is a photo of the A Frames and the signal.

HO A Frames and high resolution FUD signal

High Resolution 3D Printed Signal

The signal in the diorama photo is a pilot model 3D printed in the Frosted Ultra Detail (FUD) material from Shapeways. I did this to see if I could come up with a higher quality signal but also to try to keep the price as low as possible. I achieved this by producing the signal in FUD and the mechanism in White Strong and Flexible (WSF) like the signals available from my Shapeways shop. I made a shorter mechanism to use less material and a smaller machine space as Shapeways uses both of these parameters when calculating the print cost. I think that I can make a signal available for about AU$12 - AU$15 more than the WSF signals.

The signal is amazingly strong but it could break if given a quite hard knock. It is very difficult to break a piece of 2mm square FUD sprue with the fingers, well I can't actually.

The ladder and handrails are not printed and will need to be supplied by the purchaser. Handrails can be made from brass wire and I am developing a handrail bending jig for bracket signals. This jig can be used to make wire handrails to replace the printed WSF original ones, similarly an etched brass ladder can be used to replaced the WSF printed ladder on the original signals.

The signal in the photo above has an etched brass ladder from Peter Boorman's Workshop but other ladders can be used including Kerroby and Keiran Ryan's etched ones. I am going to add the cast iron ladder support structure at the base of the prototype ladder to the drawing.

Signal Ladder Base Support Casting

Here are some computer renders showing the signal and detail (some details are so small on the print that you almost need a magnifying glass). The detail parts have been added to the signal to eliminate the Shapeways US$5 handling charge per item to assist in lowering the final price. The structure above the detail parts sprue box is there to stop warping of the signal post during post-printing clean up. The FUD prints are heated to remove a wax used to support overhangs in the model. Of course this adds to the cost. I could remove this structure and the modeller could use hot water to straighten the post but I think that is asking for issues. Prints could be cheaper without the protective 'boxes' and structural elements but the result wouldn't be good. If a part breaks off the print is failed and too many failures and Shapeways withdraws the item from the shop.

Note the improved detail, various bolts and the cast on finial

39 inch Signal Arm with added detail

Signal Wire Pulley - At base of post.

My question though is: "Is it worth redrawing the other 19 signals in my WSF range so that the signals can be available in both WSF and FUD?"

Some feedback would be useful.

A Bit More Architecture - Werris Creek Station Building Again

A while ago I tried to restart construction of the Werris Creek station building for Ron Cunningham's Werris Creek layout and realised that I hadn't etched enough awning post cast iron support brackets Also, given that I had etched them at home the consistency of the etches wasn't that good.

I sat down at the computer, fired up Sketchup and spent several hours drawing up the bracket. The following photo of the brackets and a screen grab show the result. The brackets now had some thickness and edge flanges around the fancy bits, much better. Due to wall thickness design minimums for the Frosted Ultra Detail material I had to do some creative drawing to get more of an impression in places by impressing some detail rather than cutting through. Over all, although it isn't as fine or airy I was very happy with the resulting 3D model. The GNR didn't come out and this was probably because the height of the letters wasn't enough and the height is restricted as there is a ratio of height to width where the letters would become a wall and they would fail the minimum wall thickness test.

Rear of the brackets showing some fine lines caused by the support material used in the printing process

Other side of brackets, nice and smooth

I had originally etched the cast iron detail in the end of the awning as well so I decided to give it a go as well and this one I am very pleased with as being larger the wall thickness design minimum wasn't a real issue.

 

 

The lower awning end is for the awning on the other platform

3D printed Frosted Ultra Detail awning end

As can be seen, by using 3D printing I was able to also make the whole awning end rather than having to construct it from Evergreen polystyrene strips and shapes.

I am now at the stage with the build where I can offer the awning up to the building although I still have to add the smaller downpipes and scuppers that I had to rescale before I can fix the awning permanently.

I haven't quite finished the awning itself as I still have to fit the corrugated iron and there are 4 foot (1200mm) single fluorescent lights on the awning rafters between each post as shown in this photo.

So here we have some HO single tube fluorescents that will take a 603 Cool White SMD LED (with leads). The LED fits into a hole in the middle of the base and the wires exit the end closest to the wall to be connected to a resistor and power inside the building. The light base will be painted black and then white to try to restrict the LED light to just the tube but I am sure that it will mainly be in the centre of the tube. I am not sure how else it could be done given the restriction of the size of the base and the minimum wall design thickness.

Top

Base showing LED location and wire slot

But, there is more.

Mounted on the building as well as scattered around the platform on posts are some hooded double fluorescent lights so I have done these as well.

Here are screen grabs of the top and the bottom of the lights. The double fluorescents go inside the hood with the 603 SMD Cool White LED placed inside and the wires threaded through the hole in the end of the hood. The hole in the end of the hood and the wire slot are large enough to have a piece of 1mm plastic rod or 0.035" phosphor bronze wire (be careful here don't damage the LED wires) inserted to be used as the tubular mounting shown in the above photos.

Top

Base

Here is a photo of the 3D print, as the Frosted Ultra Detail (FUD) is translucent prints are very hard to photograph.

Well, the above have been some of the distractions I have been involved with trying to overcome the loss of our beautiful daughter earlier this year. The problem I have is completing things but I am sure that it will all come together.

On another architectural note, a comment was posted on my recent architectural post asking about cast iron lace work and panels for terrace buildings, pubs, etc. I have had these on my list for a while and do have some photos/artwork that I can work with. The problem is that a lot of the lace work is very fine and the minimum wall thickness issue will raise its head. So only certain designs will probably work. These will take some time as the conversion/tracing of the lace work and the adjustment for wall thickness is quite involved, there is also the question of how long a length of lace work panels, etc. should be designed.

A Little Bit of Architecture

OK, not architecture in terms of whole buildings but a few bits I have been working on.

A while back I was in need of distraction to keep my mind from other things and I find that the problem solving that is required for drawing up 3D items is just the thing to keep the mind occupied.

I decided that I would have a go at drawing up some corrugated iron, firstly to see if it could be done effectively and also out of interest to see how much it might cost to have printed.

I managed to track down some cross-section drawings of  'standard' corrugated iron and using this as a starting point I imported the line drawing into Sketchup as a JPG image. I then traced the cross-section and proceeded to turn it into a 3D representation within the limits of Shapeways Frosted Ultra Detail material. I had decided that the White Strong and Flexible material wouldn't give a nice smooth surface and anyway the wall thickness design minimum precluded it from the project.

Here is a picture of a print that I have had done. I had this printed to see what it looked like and to get an idea of the price, unfortunately nice as it is the price is expensive compared to available HO corrugated iron. The sheets are 10 feet long and 22 1/2 inches wide which is the visible size of a sheet of iron that has a one and a half corrugation overlap. The idea is that each sheet will but against the next on a suitable modelled timber framework or sheet of plastic and the edges of the sheets will be seen as the joint between sheets. The printed sheets are only 0.42mm thick.
 

I have since added more supporting sprue instead of the single sprue down the centre. This is to ensure that nothing will be broken off in the cleaning process after printing. The problem is that Shapeways staff don't know what a particular print is so if something breaks off, the print is rejected even if it doesn't matter to the modeller. Of course some printed bits left loose after the cleaning can't readily be identified with a particular print order.

Since the print was acceptable I then moved onto something that I had been thinking about for years, bull nose corrugated iron. Bull nose is a challenge due to the difficulty of rolling the curve to the right radius and to do so without putting a kink in the corrugations. It was also a challenge to draw, here is the result.

Now, where to from here? I was telling a friend about what I had been up to when he asked, "What about decent guttering?" I promised that I would give it a go and send him some, so this was next. Back to find a  suitable gutter cross-section from years ago (1930's, 40's, 50's, 60's, 70's, etc.). I knew that wall studs and roof rafters were spaced at 18 inches (450mm) in older houses and that gutter support brackets were usually placed on every second rafter end so this is what I drew up.

 



 And I then added sprues to give 4 x 30 foot lengths for printing.

Here is a photo of the printed gutter which I have darkened in an attempt to make the support bracket detail, etc. show better. The guttering print price looks good.

I am currently waiting on a print of a corrugated water tank which price wise at least is viable, here is a computer render of the tank and it has the correct corrugation cross-section.

Well, that is about where I am at with these items and I have decided that I will put them all on my Shapeways Signals Branch shop, someone might be rich enough to want to use the corrugated iron sheets, who knows. I am also making them available with the long term hope that the cost of printing will come down so that I can reduce the price.

Now I just have to find a nice building to make so that I can use these bits.

A Few Photos from the AMRA Liverpool Exhibition

Here are some photos I took last weekend. They do not represent every layout or my interpretation of the best layout(s). They were taken just because a particular scene caught my eye.

Please note that the photos are not up to my usual standard as I used a small pocket size camera as dragging a tripod around to take good photos is just impossible at the exhibition.

I hope that you see something to enjoy.

BINALONG

MUNGO SCOTT

ILLABO

YENDYS

PENROSE GORGE - WOLGAN VALLEY

A small amount of photo shopping was done to extend backscenes upwards and eliminate backscene joins and marks, etc.

Of course I would probably have taken more but I had too good a time catching up with many modellers. If I didn't catch up with you then maybe next time.