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Brunel Vertical Boiler Engine

Posted: Mon Oct 15, 2012 11:11 am
by ruby
Hello! Few words about my Brunel Vertical Boiler Engine . I bought it a year ago. I was probably the first Russian buyer. In the list of on the website Mamod Russia was not. But this problem is solved in two or three days.  My locomotive already not a plastic pipe for gas supply. But the axis of the wheels are fixed with rubber rings. :?:

Pros: Not noisy gas burner. Run the engine on one tank of water more than my Ruby on Aссuсraft.
Cons: Reverse is switched turning the handwheel. Difficult to regulate speed. The simple appearance.
My friends call this locomotive "mad stool." Colleague Chris Cairns  from this forum interested in photography. Here are the photos:  

https://picasaweb.google.com/lh/photo/F ... directlink
https://picasaweb.google.com/lh/photo/w ... directlink
https://picasaweb.google.com/lh/photo/T ... directlink
https://picasaweb.google.com/lh/photo/w ... directlink

Posted: Thu Oct 18, 2012 1:55 am
by Chris Cairns
Спасибо Kirill for posting your Brunel photos.

Here are some of my Brunel loco.

Image

Image

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Image

I was supposed to get one from the original batch but Mamod would only use a courier service and as I was working away from home it was sent to a customer in Australia instead. Then we had the bad winter of 2010 where courier companies refused to take deliveries for Scotland, so I had to wait until March 2011 to get my Brunel loco.

I had 2 problems with the gas burner.

1st is the burner was too close to the edge of the circular cut-out in the chassis and was affecting the flame pattern with the flame being drawn under the chassis floor. Looking at the markings on the bottom of your chassis floor in your 2nd photo you probably have the same problem. I moved the burner on its mounting closer to the middle of the boiler to stop this flame creep problem.

2nd is the gas tank gets very warm from the chassis being heated up by the gas burner and so the gas starts to pulse causing a changing flame from the burner. I fitted a felt pad under the tank to try and reduce this heat transfer, and the pulsing has now gone.

To regulate the speed you need to mark the throttle wheel with a line then keep an eye on how far open you turn this wheel (and your wheel is metal whereas mine is the earlier plastic one which does slip with the heat). I also mark the wheel on the gas tank for the same reason.

Interesting to see your style of exhaust pipe. Is that how Mamod supplied it or have you made it out of the straight pipe that Mamod supplied?

When I received mine it came with no exhaust pipes and I had a lot of problems with the exhaust condensate washing away the lubrication on the drive shaft. When I asked Mamod they said it should have been supplied with exhaust pipes (which they sent out, although explained that a vertical pipe beside the chimney had not been recommended by the review that Garden Rail had conducted on this loco, but should be left up to individuals). They sent me out 2 exhaust pipes plus a try at a vertical pipe as well. I asked why the valve block had 2 exhaust ports (previous valve locos only had 1 exhaust port) and was told it was to improve lubrication. However I decided to block off 1 exhaust port by soldering in a screw, and experimenting with the 2 styles of exhaust pipe to see which works best.

Certainly the loco could do with being fitted with a condensate trap so the vertical steam does not affect the ceramic burner. My Brunel gets very oily during use.

Chris Cairns.

Posted: Fri Nov 30, 2012 7:00 pm
by mikewakefielduk@btinterne
I feel it may be useful to list improvements/changes that we've made to the Brunel Vertical boiler in the hope that others may either consider doing the same or learn from our mistakes.

My Brunel is a recent one, manufactured in the Autumn of 2012. It's 32mm gauge. It's still running in and I'm unlikely to get many chances to run it outside on the track until the warmer weather. So far it runs at about full speed on the flat with the regulator open half a turn (opening it further doesn't make a lot of difference). Reducing it to one third open slows the loco down but at that opening it won't run up the part of my track that has a (fairly gentle) upward slope.

Comparing it with the images of the other Brunels on the forum, it was supplied with the following differences (as well as having the well known changes such as the relocated sight glass):

The axles are held on by screw-attached plates instead of rubber rings (although it came with a spare set of rings for some reason).

The gas pipe is copper.

The slots in the side frames (to allow the gas to be lit) are a noticeably different size (both larger and smaller) compared to photos of other other Brunels I've seen. No idea why Mamod should keep altering these.

Issues I've noticed:

The gas flame was pulsing when I tried to light the burner. After thinking it was a blocked jet (it wasn't) I took it back to Mamod who lit it fine with a lighter. I put my problem down to turning the gas too high and then trying to light it with a gas wand. Since then I've just turned the gas on slightly and used a match and it seems OK.

One of the wheels was wobbly. It looked as though the hole hadn't been drilled at 90 degrees to the axle. Mamod replaced them (at the same visit to the factory as above) but it took them two goes to find a wheel set without a wobble.

Bits of the loco stick out of the side of the main body, particularly the drain valve for the boiler. I've reduced the length of the drain valve's shaft and that's stopped the loco catching on things as it goes around parts of the track, but its still very close to obstructions at times. I just find this annoying as I'd originally built my track to suit the Mamod Mk11 loco and had already adjusted things once to suit a second-hand Cheddar Iver. I didn't expect to have to do so again.

Changes I've made:

The loco is top heavy and the centre of gravity is well over on one side (the cylinder side). To go some way to alleviate this I've fitted steel blocks on the flywheel side under the floor. I've also repositioned the gas tank to the flywheel side (and incidentally got rid of the rather ugly tank holding clip). Its now secured by velcro. Since making the change the loco hasn't toppled over going round corners.

Although I moved the gas tank away from its original centre location I still had to shorten the copper gas pipe by about 1.5cm before it was vertical.

I've made a small brass support to hold the bottom of the steam exhaust pipe into its slot in the frame.

I've replaced the pop-rivets with 6mm hexagonal nuts and bolts as I think they look better.

Things I'm considering doing:

Relocating the burner so its more central to the boiler, as per Chris' suggestion.

Altering the gearing so the loco goes slower.

Mike Wakefield

Posted: Fri Nov 30, 2012 11:52 pm
by Chris Cairns
For lighting the gas burner I use a butane filled Kitchen Lighter. I light this first putting the flame adjacent to the burner then turn on the gas slowly until it lights up. Leave it at that setting for about 30 secs then turn the gas up as necessary to raise steam.

It is very oversize for running on an SM32 line. At our railway group the 45mm indoor garden railway layout has a bridge parapet. So the Brunel can only run with the high cylinder placed on one side of the track - put it on the other way round and it hits this parapet.

I assume that your Brunel only has one exhaust steam outlet.

Next time I run mine I've got a Cheddar Models exhaust condenser trap to try out.

In my letter to Mamod I've asked about the proposed revised gearing for the Brunel and whether it will be made available for retrofitting.

Chris Cairns.

Posted: Sat Dec 01, 2012 4:58 pm
by mikewakefielduk@btinterne
Yes, it came with only one steam outlet. I attached the copper pipe as I didn't want exhaust steam oil all over the loco.

I asked Mamod the same question about the possibility of retrofitting the revised gearing when it finally appears. The reply was along the lines of it would involve a different frame as well (because the cog on the layshaft needs to be bigger).

I think I can change the gearing from the current 2:1 to around 3:1 and keep the existing frames. It involves using a smaller cog on the flywheel shaft and attaching a larger cog to the existing layshaft cog, forming a 2 stage reduction process. I just need to get a new drive belt for my wheel cutter (one of the advantages of being a clock restorer) and I'll give it a try.

Incidentally, how do I include photos in postings on this forum?

Mike

Images of my Mamod Brunel

Posted: Sat Dec 01, 2012 9:26 pm
by mikewakefielduk@btinterne
Image
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Image

Posted: Sat Dec 01, 2012 9:44 pm
by Chris Cairns
Mike Wakefield wrote:The reply was along the lines of it would involve a different frame as well (because the cog on the layshaft needs to be bigger).
That is a pity as to me it effectively says 'Sorry but we sold you a defective product'. Making the changes to fit the current frames would be a great boost for customer service.

If you do manage to make a successful replacement gear set I would certainly be interested in buying a set.

As to posting images there is a Topic here ( http://gardenrails.myfreeforum.org/about5505.html ) but it is not illustrated and only covers Photobucket so far. You should have a free Flickr Pro membership with your BT Internet subscription. If so you can post photos from there although there is a slight tweak required to get rid of the title that Flickr applies to the photo. Give me some time and I'll try and produce some illustrated instructions for the above Topic.

Chris Cairns.

Posted: Sun Dec 02, 2012 3:59 pm
by artfull dodger
I am watching this thread with great interest as this engine really sparks my interest as my next purchase to go along with my Regner Willi. I like the vertical boiler locos and have always had a soft spot for Mamods. I didnt realize Mamod was still actualy making engines, thought MSS was all that was left. Guess I was wrong. I second the notion of fitting a condsate trap so the exhaust can be plumbed up the front of the chimney instead of downward like an exhaust pipe for a petrol or diesel engine. Maybe by the time my bank account recovers from getting Willi, Mamod will fit the better reduction gearing to the model. Anybody have video of the engine running in the garden? Cheers Mike

Posted: Sun Dec 02, 2012 6:21 pm
by mikewakefielduk@btinterne
I'd be very interested in Mamod's reply.

Mike

Posted: Tue Dec 04, 2012 2:36 am
by Chris Cairns
artfull dodger wrote:I didnt realize Mamod was still actualy making engines
If you read my Topic here ( http://gardenrails.myfreeforum.org/about6347.html ) it starts off with how Mamod re-introduced the Mamod Steam Railway Company.
artfull dodger wrote:so the exhaust can be plumbed up the front of the chimney
You have to be very careful that no residual oil remains in the exhaust steam if you are going to pipe it up the side of the chimney otherwise you will contaminate the ceramic gas burner. The advantage of the Cheddar Models boilers is that the burners are not directly below the chimney. Have a look at the Regner vertical boiler locomotives. On the Chaloner & Willi the exhaust comes out of the condenser tank vertically. On the Max the exhaust pipe is mounted on the rear of the boiler so hopefully the fountain of water that I've seen on some YouTube videos when they first start off will be deflected backwards.

Mike Wakefield,

I guess the change to the air slots on the side of the chassis is to stop that flame creep problem that has been affecting the burner. Looks like you have moved your burner a bit?

Also notice they have change the method of changing wheel gauge, from spacers and nuts to simpler grub screws. Have they put dimples on the axles so that the grub screws have something to grip into properly?

Chris Cairns.

Posted: Tue Dec 04, 2012 8:27 am
by mikewakefielduk@btinterne
No, that was where my burner was located when it arrived. On your advice I've since moved it even further towards the centre of the boiler. Fortunately it came with a slot instead of a screw hole (to secure the burner), so it was a simple task without me having to drill anything.

Didn't see any sign of dimples to locate the wheels at the correct width.

Have not made very successful progress with the re-gearing. I've cut some new wheels but everything is so tight I just can't get the necessary clearances with the axles as they are at the moment. Its only about 1mm out but that's enough and if I make the cog on the flywheel axle any smaller there won't be enough metal remaining to have any strength.

Clearly it can be done but its going to require cutting a wider slot in the floor and some work on the layshaft axle. I'm not quite ready to go there yet.

Mike

Posted: Tue Dec 04, 2012 10:53 pm
by Chris Cairns
Mamod Ltd wrote:Finally with regard to the Brunel the frames will need redesigning as the middle shaft will have 2 gears on it so an upgrade will not be possible
Chris Cairns.

Posted: Tue Dec 04, 2012 11:09 pm
by mikewakefielduk@btinterne
Presumably they could sell you a couple of new frames plus the altered axles and cogs......

New Regulator Handle

Posted: Wed Dec 05, 2012 9:08 am
by mikewakefielduk@btinterne
Image

Thank you Accucraft!

Re: New Regulator Handle

Posted: Wed Dec 05, 2012 10:22 pm
by Spule 4
mikewakefielduk@btinterne:77482 wrote:Image

Thank you Accucraft!
Well done, happen to have an Accucraft part number?

Posted: Wed Dec 05, 2012 10:36 pm
by artfull dodger
Very nice. I would keep or install a condsate trap before routing the exhaust up the chimney. Unless I overfill the boiler, and thus flood the trap and overfill it, the only thing up my pipe on my Willi is steam vapor. Willi is also a poker burner and not the ceramic type. Next year I will have to decide whether to go for a Brunel or a Chaloner. Mike

Posted: Wed Dec 05, 2012 10:57 pm
by Chris Cairns
happen to have an Accucraft part number?
I'm also interested to hear more about this (what diameter shaft is it designed to fit?) as it is not listed on the Accucraft.com website, or the Accucraft UK website. ACME Engineering & Milton Locomotive Works do a brass one for Accucraft locos.

Chris Cairns.

Posted: Thu Dec 06, 2012 6:33 am
by mikewakefielduk@btinterne
I don't have a part number I'm afraid. Accucraft were at a small garden railway gathering last Sunday, selling some damaged and surplus bits and pieces. The regulator handles were £1 each so I bought a couple.

Mike

Posted: Thu Dec 06, 2012 7:22 am
by Chris Cairns
were £1 each
That was a very lucky break.

Chris Cairns.

Posted: Thu Dec 06, 2012 8:16 pm
by mikewakefielduk@btinterne
The regulator handles have a 4mm hole which is close enough to accept 1/8" brass rod (which is the diameter of rod I used).

No idea why Accucraft happen to have had a number of spare regulators for sale last Sunday but it may be to do with them fitting R/C gear to their locos. (As I understand it, their locos arrive from China with manual controls and Accucraft UK fit R/C as required.)

Mike