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Chris

exhaust regulator

On the yahoo 16mmngm group there are some instructions for making an exhaust regulator for mamod locos.

Has anyone tried it?

Not sure whether to try it or buy a ip/pps regulator.
Mamodman123

I haven't tried it

Nor would I to be honest
Chris

I'm figuring if it didn't work then you can just take it off and put the original exhaust pipe back.

Just end up wasting some time and a bit of money on copper pipe.



Would want comment from someone who has tried it though.
tmuir

I have made the exhaust pipe and have it installed on my loco but never made the top half as on 45mm track derailing wasn't an issue for me and now I have a proper regulator fitted don't need to.

I can't see why it wouldn't work though and its certainly cheaper than buying an IP regulator so if your looking for more control on the cheap, give it a go.
SillyBilly

I may do it when I finish my SL1, but I haven't sent the boiler away for repair yet, so it'll be the end of the year till it's finished (I loose intrest quickly, I'll keep you informed when I do it!
Chris

Have emailed the guy who wrote the instructions for a couple of clarifications and I think I might give it a go.

Need to order some copper tubing, should be able to try it for about £3 so if it doesn't work I will have lost nothing really.
Mamodman123

Chris wrote:
Have emailed the guy who wrote the instructions for a couple of clarifications and I think I might give it a go.

Need to order some copper tubing, should be able to try it for about £3 so if it doesn't work I will have lost nothing really.


All part of the learning curve Chris!

Let us know how you get on
Chris

Mamodman123 wrote:
Chris wrote:
Have emailed the guy who wrote the instructions for a couple of clarifications and I think I might give it a go.

Need to order some copper tubing, should be able to try it for about £3 so if it doesn't work I will have lost nothing really.


All part of the learning curve Chris!

Let us know how you get on


Just ordered some pipe, just hope I have ordered the right stuff. Probably screw up, but hey, it won't cost much to try, and will just take an hour or so of my time. Then I will swear at it, take it off and phone pps for one of their proper regulators!
Chris

Slow progress on this little project.

The copper pipes arrived yesterday, so hopefully get around to making it over the weekend. It was vital that one pipe fits snugly inside the other, which they do so that is good.

If anyone is interested the plans can be found on the yahoo 16mmngm group. I won't post them up here as they are not mine, but I will put some photographs up when I make it.
Mamodman123

Sounds promising so far chris
tmuir

I'm interested in the results of this Chris as I have that regulator half built and installed in my loco but I dont need it now.
Chris

I should have bought the half built one from you.



I'm interested to see the results too, I am preparing myself for failure!
tmuir

Even if it doesn't work having the exhaust pipe almost all the way to the top of the chimney is good as it means more of the exhaust condensate gates thrown out of the chimney rather than dribbling back down onto the burner.
Mamodman123

tmuir wrote:
Even if it doesn't work having the exhaust pipe almost all the way to the top of the chimney is good as it means more of the exhaust condensate gates thrown out of the chimney rather than dribbling back down onto the burner.


True Tony!

IVe got some old sponge in mine now you mention it
syrtismajor

Any luck there yet Chris?
Curious to know if it works and whether or not you get a satisfying 'chuff' out of it
If it works I'm liable to put one on Sovereign (when built of course)
Chris

Started work on it this morning.

Rain stops play at moment (workshop is a picnic table in the garden).

The copper tubes - 1/8" for the new exhaust pipe, and 5/32" as that fits nicely over it (bit lucky as ordered over the internet but K&S have a good website listing the internal and external diameters of the pipes). Photo also includes original exhaust pipe.



I discovered I am not very good at bending pipe. Here is the new exhaust pipe.



Next stage, block of the end of the exhaust using solder and cut a small slot in the side of the pipe.



Then cut a larger slot into the 5/32" pipe to act as the regulator tap.



More progress later. I need to make some kind of cap for the regulator bit and put it all back together.
Sandman

Good going Chris.

Just one thing though. Did you anneal the pipe before you tried bending it??

If not you'll find it helps a lot.

Also try using a brush shaft or something to bend it round.

Just a couple of suggestions mate.

Best of luck.
tmuir

Yes I've used that brand of copper pipe, its very hard and needs to be annealed before you can bend it safely.
I ruined a length of that pipe before I realised that.....
MooseMan

For bending tubes I couldn't live without my mini tube bending springs - they allow you to bend the pipe without kinking it:

http://www.greenweld.co.uk/cgi-bi...king_301%2ehtml%23aTL9730#aTL9730
Sandman

MooseMan wrote:
For bending tubes I couldn't live without my mini tube bending springs - they allow you to bend the pipe without kinking it:

http://www.greenweld.co.uk/cgi-bi...king_301%2ehtml%23aTL9730#aTL9730


Handy to know and not expensive either.

I'll get myself a set of these.

Thanks mate.
MTA

I see how this works now. It's a bit like a bunsen burner arrangement in school isn't it
newavenger

Just thought I would post this suggestion, when I was working I had to make small induction coils from 1/4" copper pipe with some really tight turns I found that bu filling with water and freezing the pipe did not kink, have not tried it on anything smaller but it does work.
Chris

MTA wrote:
I see how this works now. It's a bit like a bunsen burner arrangement in school isn't it


Exactly it MTA. Just uploading the next lot of progress photos... and a video!
Sandman

Chris wrote:
MTA wrote:
I see how this works now. It's a bit like a bunsen burner arrangement in school isn't it


Exactly it MTA. Just uploading the next lot of progress photos... and a video!


Good Good.
tmuir

newavenger wrote:
Just thought I would post this suggestion, when I was working I had to make small induction coils from 1/4" copper pipe with some really tight turns I found that bu filling with water and freezing the pipe did not kink, have not tried it on anything smaller but it does work.


I've done that on 1/8 pipe before and it does work, but being so fine the ice starts to melt almost straight away from just the warmth of your hands so you have to have everything set up by the freezer and be ready to go as soon as you remove it to minimise the thawing.
Chris

Ok, here goes.

I needed to make a handle for the regulator. I found that a screw cap fitted nicely, although it does look a little daft (not sure of the proper name, you use them to make the heads of screws look nice when you use them to screw mirrors to a wall).

Here a a photo of the completed regulator with it open...


And here with it half open. I hope this helps explain how it is supposed to work...


The exhaust pipe in place...


Running on blocks...




Lessons learnt.
I think I should have made the regulator bit longer just to make it harder for steam to escape under it.
The screwcap is far to slippery to turn.
I had the loco running very slowly around the track with no wagons, so the principle works (then it rained hard so no video of that).
It is good I at slowing the loco down, but doesn't add much to the amount of control.
I think the slot in the exhaust pipe should be narrower.

I will make a new top bit for the regulator at some point and try again with that.

The mean lesson learnt is that it took just a couple of hours of my time, has not damaged the loco in anyway, and only cost a couple of quid! So I am a happy bunny.
tmuir

Glad it works, I agree you need a bigger 'handle' for the exhaust pipe so you can keep your fingers away from the steam.

Did it give you any more chuff?
Chris

tmuir wrote:
Glad it works, I agree you need a bigger 'handle' for the exhaust pipe so you can keep your fingers away from the steam.

Did it give you any more chuff?


Not as much as I was hoping for, but yes I think it did chuff a bit more. I will put it to work towing some wagons and that will be a better test. I think it needs to be a bit more steam tight at the top. I have loads more of the 5/32" pipe so I will make a new top at some point.
MTA

Glad it worked Chris. Good to hear that you are going to improve it, would like to see how good it can get
Mamodman123

Pretty good for the first try! Rome wasn't built in one day

Must be pretty hot at the top of that chimney?
Chris

MTA wrote:
Glad it worked Chris. Good to hear that you are going to improve it, would like to see how good it can get


Yes, I will run it like this for a while to ponder how to make it better. The main purpose of this one was to see if the principle works, which it does.

When the weather clears up I will do a video of it running on the tracks (probably not this weekend then).
SillyBilly

Thanks, I think I'll be attempting it in the future!
Chris

Right, I don't mess about me... MK I made in a morning... MKII made in the afternoon.

Same exhaust pipe, new top regulator bit. I have tried to make it look like a chimney cowl.





Running on blocks...



Running on track (sorry about the quality, I was trying to keep the camera near the engine so you could hear the chuff/pop/throb the steam makes as it forces it's way out of the regulator). This is with the normal mamod regulator quite a long way open, and the exhaust regulator quite a long way closed...

Mamodman123

Certainly has a bit more of a chuff noise!

Mk 2 looks a little better too

What is the result then? worth doing? not worth doing?
Chris

Mamodman123 wrote:
Certainly has a bit more of a chuff noise!

Mk 2 looks a little better too

What is the result then? worth doing? not worth doing?


I want to try pulling some wagons before deciding really. I am still a bit reluctant to take Authur to bits to fit one, this is on my other loco. Considering it has standard pistons I would say that it certainly seemed to still have a lot of pulling power, but I will know for sure when the weather clears up and I get some wagons out.

For the money and effort then I would say it will be worth it. The IP/PPS regulator is £23, this one was about £3 and I have enough pipe left to make another one. Also there is no modification to the loco, so if you don't like it take it off. No hole in the back of the cab to worry about. In reality it is probably as easy to make this than it is to fit the PPS regulator anyway.
tmuir

Seems to work very well.

May a suggest a minor mod to MKIII.
Put some marks on the ring around the top so you know how far you need to twist it to get full, half and slow throttle.
Chris

tmuir wrote:
Seems to work very well.

May a suggest a minor mod to MKIII.
Put some marks on the ring around the top so you know how far you need to twist it to get full, half and slow throttle.


Yep, you can tell that with this MKII version by looking to see what direction the brass cross piece is pointing. Bad soldering at the front = full power, bad soldering at the back = off.

tmuir

Chris wrote:
tmuir wrote:
Seems to work very well.

May a suggest a minor mod to MKIII.
Put some marks on the ring around the top so you know how far you need to twist it to get full, half and slow throttle.


Yep, you can tell that with this MKII version by looking to see what direction the brass cross piece is pointing. Bad soldering at the front = full power, bad soldering at the back = off.





Ok you have already got it covered.
Mamodman123

It's certainly worth a try then! If it doesnt work out then it won't cost the earth

Great stuff Chris
Chris

I bought the tubing from these people...

http://www.cheshiremodels.co.uk/acatalog/k&s1.html

Tubes are cheap but postage is steep. Generally would recommend them though.

This size chart on the K&S website helped with making sure I was buying the right size tube...
http://www.ksmetals.com/Cuttolength/chart.asp
Wallace

Very nice Job Chris


Thanks for the link to K&S metals.

Someone on here was asking about where to buy brass.

I buy that brand from our local hobby shop. And if our hobby shop has it, then just about any hobbyshop in the world should
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