Another Pennsylvania A3 Switcher

[JCvdW]

Thanks Kim for the commiserations! Spray painting is indeed a big learning experience for me. But isn't this one of the main reasons for doing all of this? 

For my next project (if there ever is one!) I will certainly consider powder coating. You are not the first one to suggest this to me!

Today I pressure tested the hand pump and high pressure plumbing.

Following Blondihack's lead, I first made a boiler simulator, consisting of a pressure gauge, a standard irrigation non-return valve and a blow down valve. All have BSP taper threads.  The available (pneumatic) adapters also only have BSP taper threads. I do not have any BSP taps and/or dies and they are expensive! So I modified a  pneumatic quick release connector that only costs about 2 dollars into a BSP to M8 metric adapter.



This adapter was then screwed into and epoxied to a brass adapter that accepts the M8x1 union nut and brass nipple at the end of the high pressure rubber tube.



And this is the complete boiler simulator:



After fiddling a bit with the pump and plumbing, the maximum pressure reached was about 800 kPa, or 115 PSI. At this pressure the nipple joint popped out of rubber tube. The hand pump was not close to its limit yet.



Conclusions from the test:

1. The hand pump is more than capable of pumping water into the boiler up to its maximum working pressure of 100 PSI.

2. The rubber tube is way too soft and acts like a balloon. A flexible high pressure rubber tube will have to be found.

3. The nipple joint for the rubber tube may need some barbed ridges to prevent the tube from sliding off.

With the pump tested, it is time to seal and assemble the tender!

[PaulR]

Just to let you know that Imgur images are no longer visible to UK forum members

[JCvdW]

Thanks Paul for letting me know.

Any suggestions on which image server to use going forward? I have only used imgur on this forum up till now.

[Kim]

Kozo recommends putting a braided sleeve over the hose between the tender and the engine, which would help deal with the pressure.  But you may still need different tubing.

I use the CopperMine server that Ade hosts.  That works for me. It is a little more challenging now that it doesn't support multi-image uploads (You have to do them one at a time now that Flash has been decommissioned by all the browers) but it still works well enough.

Just a thought.  I'm sure there are many good options.

Kim

[JCvdW]

Just to let you know that Imgur images are no longer visible to UK forum members

I have moved the images in the last post to Google Cloud. Will someone from the UK please confirm if it is visible now?

[JCvdW]

Kim, the braided sleeve does help a bit, but unfortunately not enough. The tube balloons too much...

The tender tank must be sealed during assembly. Generous amounts of SikaFlex sealant was used on the inside of the tender to seal any potential leaks in the soft solder joints, and where the screws for the steps and railing protrude into the tender.

The tank ready to be bonded to the floor:



The floor, with the pump and plumbing installed and sealed, screwed onto the tank. Holding thumbs that the seal between the floor and the tank will be watertight!



To complete assembly of the tender, all the visible screws in the trucks, frame and tank were replaced with scale bolts from Knupfer. The heads of these stainless steel and brass bolts were first spray painted black.

All the bolt heads ready to be sprayed black in the spray booth:



Finally, the tender is fully assembled! The e-clips holding the trucks under the frame installed for the very first time!









When pouring water into the tank, the axle pump suction pipe made my heart miss a beat or two, as it is of course open. With the suction pipe sealed off, the tank thankfully seems watertight!

This brings one to the point in his book where Kozo wants you to start on the engine, but I am thinking of making the headlights and couplers first, to fully complete the tender.

[wagnmkr]

That is one LOVELY looking tender!!

 

Tom

[crueby]

Beautiful!   


For the tube, I  once got some black rubber tube with the braided reinforcement  embedded  within the tube walls. Got it from The Train Department,  likely  is available  elsewhere  too. Handles the pressure without ballooning.

[Dave Otto]

Beautiful work, your paint job and detail is especially nice!

Dave

[Kim]

Wonderful!  Your tender looks beautiful!  You did an excellent job on the paint and finish, and it really shows! 

Kim

[JCvdW]

Thanks everyone for the kind comments! To quote from Section 37 of Kozo's book: "...painting may be one of the biggest jobs...". And so it turned out to be!

[JCvdW]

For the tube, I  once got some black rubber tube with the braided reinforcement  embedded  within the tube walls. Got it from The Train Department,  likely  is available  elsewhere  too. Handles the pressure without ballooning.

Thanks Chris! I think I have also found a high pressure tube that would still be flexible enough - a flexible hose for a Groz grease gun. It has approximately the right OD, and can handle serious pressure. After heating with a heat gun, the ends can be expanded a bit to fit the nipples.

[crueby]

For the tube, I  once got some black rubber tube with the braided reinforcement  embedded  within the tube walls. Got it from The Train Department,  likely  is available  elsewhere  too. Handles the pressure without ballooning.

Thanks Chris! I think I have also found a high pressure tube that would still be flexible enough - a flexible hose for a Groz grease gun. It has approximately the right OD, and can handle serious pressure. After heating with a heat gun, the ends can be expanded a bit to fit the nipples.

Excellent!