# Accucraft Garratt Blakeman Mods



## RP3 (Jan 5, 2008)

I have just purchased but not yet taken possession of a black Accucraft Beyer Garratt. Since it was bought by Internet auction, I don't yet know what version it is -- although I suspect it is from the first run. To prepare for its arrival, I have been reading about its issues and the solutions that many people have used to bring its performance up to par. These include: the plate in the bottom of the smokebox to protect the silicone tubing, bogies, etc; reworking the exhaust to further protect the silicone tubing and to eliminate back pressure in the exhaust; installing an adjustable lubricator; the usual gas burner complaints; and the gas tank recall. But many folks keep referring to the Blakeman mods without any explanation, and I would like to get a handle on what these are -- assuming they are not the same issues that I have already mentioned. I would really appreciate hearing from Rod or any other knowledgeable folks about what these mods are.

Thanks in advance for any help received.

Ross Schlabach


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## Garratt (Sep 15, 2012)

Ask the man himself.

Email: [email protected] 

Andrew


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## RP3 (Jan 5, 2008)

Thanks! I will.

Ross Schlabach


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## Kovacjr (Jan 2, 2008)

Ross, A while back I posted the mods I did to Stan's Garratt. Where and how to find them would be beyond me. 

Basically - 

Crosshead guides soldered a backing plate on as the fall off the guides 
Exhaust rerun 2 separate pipes 
Throttle split just after the lubricator, rear engine no superheater and front superheated 
Oiler used the large Regner 
All rods were re-bushed with oilite bronze bushings and reamed for each pin.


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## RP3 (Jan 5, 2008)

Hi Jason, 

Yes, thank you. I had found the text and photos you had posted covering your mods -- I'd forgotten to include the crosshead mods but I had read them over. And most of the crosshead repairs are going to be beyond me too so maybe it was a case of convenient forgetfulness. 

I thought my modifications and repairs to the C-19 were a big deal -- after all I did have to remove the boiler and shell -- but this is going to be a bigger challenge what with the silver soldering and other serious plumbing to be done. But the model is worth it! Wonder if I should consider replacing the O rings with Rulon while I'm at it. Recommendations? 

Ross Schlabach


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## RP3 (Jan 5, 2008)

Jason's posting got me to thinking.Is there any advantage to splitting the steam after the lubricator and leaving both engines with UN-superheated steam instead of having the front superheated and the rear not? After all, this would eliminate the problems that arise when you superheat the steam oil and having a single T in the steam line under the cab would make steam lines to both engines about the same length. Obviously both lines would benefit from some insulation. The logical alternative would be to keep the existing superheater arrangement and provide serious insulation for the rear steam line. 

Just thinking out loud! 

Ross Schlabach


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## TonyW (Jul 5, 2009)

I have a Batch 3 Garratt. These can be easily identified as they have a steel strip across the top of the cab doorways to strengthen the cab structure. 

Batch 3 locos do not have superheat for the rear engine as the outlet pipe from the lubricator has a tee that supplies the rear engine directly. However, this is not the best arrangement as the rear engine supply requires the steam to "turn right" while steam for the front engine (which is superheated) has the easier path by going "straight on". 

I have done a few modifications on mine to improve its performance... 

Two new gas burner jets improved the burner efficiency and stopped the occasions in which one burner would go out for no apparent reason. 

The exhaust back pressure can be virtually eliminated by removing the exhaust pipe in the smokebox. It consists of a short length of 3mm pipe that has a pipe union at one end (which fixes to a tee underneath the smokebox), while the other end is crimped and drilled from the side. It is a 30-second job to remove. This means that the only exhaust passage that is shared between the two engines is the very short (about 5mm) upper connection on the tee. If you are feeling ambitious, the tee can be removed and drilled through to a greater internal diameter to allow even easier exhaust steam passage. I have not done this on my loco but I will do so should I need to have it apart for another reason. 

I have had both safety valves remachined and reset. Prior to this one weeped steam constantly and when it lifted at 60psi-ish the hysteresis (time between opening and closing) was far too long, not closing until the pressure was below 40psi. Now one lifts at 60psi and closes with satisfying sharpness at 55psi. The other is set for 65psi and shows similar behaviour. Well worth doing!


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## seadawg (Jan 2, 2008)

Posted By TonyW on 30 Oct 2013 05:01 AM 
I have a Batch 3 Garratt. These can be easily identified as they have a steel strip across the top of the cab doorways to strengthen the cab structure. 

Batch 3 locos do not have superheat for the rear engine as the outlet pipe from the lubricator has a tee that supplies the rear engine directly. However, this is not the best arrangement as the rear engine supply requires the steam to "turn right" while steam for the front engine (which is superheated) has the easier path by going "straight on". 

I have done a few modifications on mine to improve its performance... 

Two new gas burner jets improved the burner efficiency and stopped the occasions in which one burner would go out for no apparent reason. 

The exhaust back pressure can be virtually eliminated by removing the exhaust pipe in the smokebox. It consists of a short length of 3mm pipe that has a pipe union at one end (which fixes to a tee underneath the smokebox), while the other end is crimped and drilled from the side. It is a 30-second job to remove. This means that the only exhaust passage that is shared between the two engines is the very short (about 5mm) upper connection on the tee. If you are feeling ambitious, the tee can be removed and drilled through to a greater internal diameter to allow even easier exhaust steam passage. I have not done this on my loco but I will do so should I need to have it apart for another reason. 

I have had both safety valves remachined and reset. Prior to this one weeped steam constantly and when it lifted at 60psi-ish the hysteresis (time between opening and closing) was far too long, not closing until the pressure was below 40psi. Now one lifts at 60psi and closes with satisfying sharpness at 55psi. The other is set for 65psi and shows similar behaviour. Well worth doing! 

Tony, did you do that work on your safety or did you shop it out?


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## Chris Scott (Jan 2, 2008)

Positively No 1 modification, adjust the timing of each engine, if it hasn't been already. (forget if you said it was new or preowned.) While it’s a case of never getting the two precisely the same overall it makes a whole world of difference. Timed properly the smoothness of the Garratt will totally surprise. Trust me, proper timing on the Garratt is vital. Timing right it virtually glides from a standing start. Yes, I love my Garratt. Tuck it in every night. 


The engine needs to run at high pressure, 60psi constant to run smoothly. Ian told me he recommends 80psi, I think he said the Garratts sold in the UK are set at 80psi. Problem is the boiler is on the small side meaning you have to add water more often. 


You don't necessarily have to have a plate under the smoke box if you don't run with the fire stuck in the smoke box or run the burners at blow torch levels all the time. There are about 120+ Batch 1/2 out and I doubt many at all have added the plate. All comes down the engineer. 


The burners are not ideal, Tony’s quite right, but with all the piping in the cab there is a lot to unbutton to get them out. I’d go back to correct timing. I’ve not fixed the burners, other than a bit more noise alls fine. The larger diameter of a 16mm scale engine also helps reduce noise


I wonder a bit about the right angle steam line thing since it would seem the length of the one steam line and a right turn in the other and with steam traveling a much shorter distance the two would balance out. Just a thought.


Tony mentioned the steel strip across the top of the cab doorways to strengthen the cab structure. This helps a lot to strengthen the cab, simple to add. I've had both Batch 1/2 and now Batch 3. Without cab strip I was often hitting the rear half and having to “adjust” it.


Make sure the grease on the steering UV joints is on the gear teeth. It’s not well applied at the factory, just a blob. Makes the stiff steering somewhat easier. When changing direction make sure to back off the steering from stop about half a turn.


A must have, make a longer steering wheel !!! You will understand why the first time you go to change direction. I think Tony will readily agree.


Can be very difficult to light the burners given the limited amount the door opens due to the limited front engine swivel. Buy a piezo lighter the pistol or gun type, has a long (3/8” x 8”+/-) pipe business end. With it you don’t need to see into the smoke box. Insert it until it hits the end of the boiler. The flame almost immediately pops back with the spark right up against the flue. A little side-to-side movement of the spark tip makes sure both burners are lit. IF one isn’t you’ll very quickly hear the flame pop back.

Have fun.


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## TonyW (Jul 5, 2009)

Seadawg: 
I shopped it out to one of our Accucraft UK repair agents, Chuffed2Bits (http://www.chuffed2bits.com/), as it is a service that they offer. And for what Mike charged to do the job it was not worth doing it myself. 

Chris: 
Without any of the changes mentioned in my earlier posting, I have to say that mine ran nicely straight out of the box and I have not had to adjust the timing. I think this may be connected with there being no steering wheel on my loco as it is fitted with radio control. This was installed before the loco came to me by another Accucraft UK repair agent, and I suspect - but do not know for sure - that any timing issues or other bugs were ironed out as part of their testing of the radio. 

Another essential tool I have is a dentist's mirror. 3/4 inch diameter, extending handle, swivel head, bought of ebay very cheaply, I would not be without it as it allows a good visual check of what both burners are doing. The mirror will fog when first placed anywhere near the smokebox door, but leaving it there a few seconds to warm up then wiping the glass clean and placing it back in the smokebox will then give a good view. 

I'd forgotten another modification: A warm water supply for the gas tank reservoir. Mine came from DJB Engineering (http://www.djbengineering.co.uk/w-valve.html) and, again, I would not be without it.


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## RP3 (Jan 5, 2008)

Thanks to all for the advice and suggestions. When I picked up the loco, I discovered that it was a first run as I had suspected but it is also a virgin - no run time. The fuel tank will need replacing on account of the recall and I expect to do a number of the mods covered in the thread. Judging from the walshaerts positioning at various points, the two engines appear to be well coordinated. But actual testing will prove or disprove that hypothesis. I've got a DJB warming valve and whistle on order. Haven't decided on RC yet. I normally RC my engines but I'm not convinced of the need or advantages on this locomotive -- especially given the removal and soldering needed. But I will definitely be replacing that regulator knob with a lever for better access. 

Ross Schlabach


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