Building Fred

[zeeprogrammer]

I really WANTED to build this locomotive...

The key to all success.

I always enjoy your builds.

[arnoldb]

Thanks Carl - and LikeWise 


13 December 2009
finished the top cylinder covers and the 2 pistons:
 



17 December 2009
I made the 2 con rods from stainless steel - threading one end (to get rid of the last bit that wasn't threaded properly, I just used the edge of a small half-round file to make the undercut after doing this thread):
 
 
 
19 December 2009

Saturday I made the bottom cylinder heads. Here I deviated significantly from the original plans. The originals show a simpler solution, but would be more difficult to disassemble for maintenance later on. I opted for cylinder heads that could bolt on - after checking that adequate clearance was available for these, and traditional stuffing glands. Digging around available stock, I decided to make each head out of 2 parts to minimise stock wastage
 
 First up, machine the "inside" face of one, with a register to accurately locate on the cylinder head:
 
 
 Grabbed the register part in the collet chuck after both were done in the 4-jaw, and faced to thickness with light cuts; there's not a lot getting held in the chuck! :
 
 
 A bit of a lapse in photos followed; I drilled & reamed the some brass threaded rod I have to 4mm for the inside of the stuffing glands. Then drilled part-way to 5mm & threaded to M6. A "modified" m6 cap screw was used to cut the thread to final depth, as I don't have an M6 plug tap. The outside of the rod was then turned to a tight fit for the 8mm holes I made in the cylinder heads earlier. Parted off, pressed into the cylinder head, and repeated for the other one.
 
 I decided to go the studs 'n nuts route to bolt the heads to the cylinders; the studs to be loctited into the cylinder, so instead of faffing around with a 1.4mm tapping drill for the 10BA studs, I went with 1.5mm; my drill press chuck can clamp 1.5, but not 1.4. Toolmakers' clamps keep the cylinder heads in place while drilling:
 
 
 All bolted up; the side of the cylinder head on the port face side is intentionally shorter; I don't want it running against the port block.
 
 
 I wanted to carry on past this on Saturday, but social life made a call & off to a BBQ I went; that's also why I didn't update last night...
 

20 December 2009

 This morning, after recovering from a very late night out, I started on the engine mounting. 2 weeks ago, I found some brass plate offcuts at the place I get stainless steel from; I put a corner of a triangular piece of 2mm plate to use:
 
 
 After some free-hand bandsawing:
 
 
 And some time & sweat with a file:
 
 
 This piece of plate was nice and soft, so I marked out the mounting feet on a flat piece, and used a hammer and the big vice to make it into an angle:
 
 
 Once again using the toolmakers clamp for drilling an awkward-to-hold piece:
 
 
 Now comes a bit of a booboo...
 Having made the engine mounting & it's feet, they needed to get soldered together. No soft solder for this one, silver solder is needed for a high-strength joint.
 With the back edges of the feet a bit round from bending and difficult to keep square, I decided to use a piece of aluminium angle to keep everything together and nice and square, and to let the silver solder flow onto the "round" part to make the mounting nice and flat. It looked so good all set up and fluxed, ready for soldering:
 
 
 Used my oxy-butane kit to heat up one side; flux bubbled, flowed & I needed "just" a bit more heat for the solder.... then the ally called it quits:
 
 Sorry; poor photo; I was just a tad annoyed. Might have worked with thicker aluminium, might not...
 
 So I left everything, including myself, to cool down, cleaned the parts up again, and used bits & bobs to hold things in place and re-did the job:
 
 
 Dumped the mounting in citric acid for 1/2 hour - came out OK; I overdid the silver solder on the one foot, as it moved while doing it. I'll clean the excess off later and neaten up the mounting:
 
 
 Next up, marked out the mounting holes on the loco frame for the engine mounting; lots of calculations needed off different sheets of the plans to get correct measurements, but finally got it. Used a square to make sure things stay in alignment, and the 2mm drill bit finger-twirled through the mounting holes to mark the spots through the paint.
 
 
 Drilling 1.6mm holes for M2 tapping on the marks after punching. I supported the frame on the vice jaws, and held on firmly. Drill press set to 1500 rpm, and a good positive feed used, as I don't want a repeat of the stainless angle work-hardening like I had earlier in the project:
 
 
 The tapping guide I made for the 10BA taps works well for the 2mm taps as well, so just tapped the holes after drilling; using all three taps in sequence.
 
 Next up, I calculated & measured the correct end of the port block for drilling & tapping the mounting holes. I stuck some masking tape on the port faces to protect them in the vice while drilling the holes; with the drill press depth stop set so I would not break into the steam passages on the inside. Tapped these holes as well, and to get to depth, I ground the tip with the broken teeth off the 3rd tap in my old M2 set, and used it to thread to bottom on the holes  - never throw away "abused" taps! - Sorry no photos again...
 
 Mounted everything up for a look-see & to see where problems might (DID) arise. Lots of screws to shorten/make, and parts to give a final finish to still left here, but tests first:
 
 
 
 Now the problems started...
 When turning the engine over by the wheels, it was still very stiff; I felt the pistons were stiff in the cylinders earlier; primarily because of the o rings, and I hope that will wear in properly. Couldn't go full-throw to the bottom of the cylinder stroke; checking, I found that I must have made a mistake somewhere, and that the port block is mounted about 1.5mm too high. Top of the cylinder stroke with the big ends disconnected has adequate clearance, so I'll make new con rods, 1.5 mm longer; easier than to re-do all the mounting holes!.
 
 And then the real spanner in the works hit... After dismantling the engine, I just gave the main drive wheels a spin, and they were stiff and wobbled! - never did that; was running very smooth up till now. Closer inspection, and the loctite had come loose on the crank pins, and the assembly warped. So, I need to disassemble the crank assembly and drive wheels and re-do it. This time, I'll silver solder it. Oh well, more practice 

Regards, Arnold

Edited to sort out post text that ended up in all bold...

[arnoldb]

25 December 2009

This morning, I disassembled and cleaned the cranks/wheel assembly and cut a new piece of piano wire for the main shaft. Then cleaned everything very well, and assembled with flux on all the shafts. I took some time to clean off excess flux from where I didn't want it - on the shafts where the big ends connect and outside the wheels . Then using the oxy-butane welding set, with the flame set to an orange smoky flame, I gave everything a quick once-over - left a black deposit on most everything. Then I turned the gas up to a nice blue flame, and silver soldered it with tiny dabs of the rod, using the flame heat to draw the solder. Worked a treat  - had very little excess to clean off, but everything soldered up really well. I can kick my own butt - I didn't take photos.
 
 Then dumped the assembly in citric acid to pickle. While waiting for that, I made the new 2mm longer con rods.
 
 This afternoon I cleaned up the wheel assembly. The pistons were a bit tight in the cylinders as well, so I removed the O-rings for now.
 Then reassembled the whole lot and did a trial run on 5 psi compressed air.

<a href="https://www.youtube.com/watch?v=D_2njB1ykxE" target="_blank">http://www.youtube.com/watch?v=D_2njB1ykxE</a>

Looks like it'll work  - has good torque at 5 psi, and with increased pressure, I can barely stop the wheels.
 
 Next up, some boiler making....


26 December 2009

This morning I started with bits of copper. I have never really worked with this metal, so this is pretty much an all new experience for me. A piece of 42mm tube 1.5mm thick for boiler shell, a piece of 15mm tube for inner tube, and two pieces of 2mm thick copper plate for the boiler end caps; roughly sawed to shape:
 
 
 I drilled 6mm holes into the centers of each bit of plate, and screwed them on a rough mandrel using available bits & bobs in the lathe to machine to shape:
 
 
 The copper was all gummy to machine dry, even though I sharpened up the cutting bit pretty well for the job. So I tried a couple of drops of my favourite cutting/drilling/reaming fluid for each pass; that helped a LOT and made the chips come off nicely, with a decent finish:
 
 
 Then I annealed the discs again, ready for forming:
 
 
 All clamped up for forming; I knew I'd find a use for those cheap sockets I have laying around  - this one is the exact size required for the ID of the end cap; saved me the hassle to turn a form tool from good stock!:
 
 
 Formed - I used a smallish hammer to get it to around 45 degrees formed on the side, then used a 4lb (sorry ~ 2kg!) hammer to just bash it down while revolving the lot the whole time. I thought I'd have to stop and anneal the cap again, but didn't need to.
 
 
 Same process followed for the other end cap. I then drilled the center holes out to 13mm on the drill press and drilled holes as needed for the hedgehog spikes in the bottom end cap and for the bush mounting holes in the top cap. All the holes came out "triangular" instead of round - horrible stuff to drill - even with cutting fluid. To get the 8mm holes for the flanges to shape (i.e. round), I just used a hand reamer. I don't have a 15mm drill or reamer, so just chucked the end caps and bored the center holes to size:
 
 
 End caps done; can anybody spot the "deliberate" mistake ? :
 
 While drilling the holes for the hedgehog pins, I drilled one in the wrong place  ... resulting in uneven distribution. I'll just call it a "Design Feature" for now 
 
 Then I turned up and threaded the required bushes from phosphor bronze (what a pleasure after working with the copper!) and was basically ready to clean everything and start soldering together.
 
 There was something wrong though; that "funny" feeling in my tummy was telling me to hold up a bit. So I sat, thought, went through the plans, thought a bit more, and remembered I forgot about the alignment for the water level gauge.
 
 So I started on the bits & pieces for the guage glass; simple turning & threading of bits of brass rod - I'm really glad I made those tailstock die holders!, though I wish I had invested in M5 and M6 Fine taps and dies as well; would be much better suited to this purpose. Next two photos shows the parts fluxed up (maybe too much!) and ready to be silver soldered:
 
 
 
 All soldered up; still too much solder applied though! :
 
 
 After about 30 minutes pickle in some citric acid:
 
 
 The net results of today's work on Fred:
 
 

Regards, Arnold

[Dan Rowe]

Arnold,
Very nice. I like the tip about checking the socket drawer for a suitable end former.

Dan

[arnoldb]

Thanks Dan  - I might be needing an end former again in the very near future; I'm between projects at the moment and can't make up my mind exactly what I want to do next 


27 December 2009

On to today's work. One thing I have learned from my limited silver soldering endeavors is that I'm inclined to use too much solder, so one goal for today was to hold back a bit.
 
 A lot of pickling would be needed, so I made up a citric acid pickle bath from an empty 5L plastic mineral water bottle:
 
 
 Most parts dumped in the pickle - the small yellow container has the bushes and copper rivets I intend to use for the conduction pins:
 
 
 While those were in the bath, I laid out the boiler shell for the water gauge holes, and the air ventilation holes - here I'm getting the gauge holes nicely in line with a new "backed" square I bought a couple of weeks ago:
 
 
 After drilling the needed holes in the shell, I added that to the pickle as well. The bottom cap and copper rivets looked good, so I assembled the lot with flux:
 
 
 Soldered - I used a smallish butane torch, not the Oxy-Butane set, and just quick light touches of the solder rod to the joints - got better while working:
 
 I only took time to take the photo, and then dumped the cap stright back into the pickle; a bit of steam and bubbling, but most of the black stuff & flux came off straight away.
 
 Same treatment followed for the top cap and bushes - I drew pencil lines about one mm away around the bushes as a test. Worked OK except for the spot where I accidentally touched the rod on the cab between the bushes... :
 
 
 
 The bottom cap was lying in the pickle while I did the above; when I touched it, some of the black that was left came off, so I fetched a retired clean toothbrush, and just scrubbed at it a bit and it was nice & clean in no time. On closer inspection, there was just one pin that was not soldered properly, so I just added flux to it on both sides, re-heated the lot and gave it a quick dab again. Photo of the "dry joint":
 
 
 Next up, it was the bushes for the gauge glass on the boiler shell - the pin keeping alignment is a length of stainless steel rod:
 
 The butane torch had a really hard time of getting everything to temperature for this, even though I tried to get as much heat containment as possible... At one point - just as everything started reaching solder temperature, the torch went out. So I let things cool a bit, added more flux and started again. Eventually got the job done adequately, but not good looking.
 
 I also soldered the center flue to the bottom end cap; it is easier to do this before final assembly, as I had the opportunity to check it and the end cap for a good seal. Tonight the parts will spend in the pickle; hopefully I can get a couple of minutes of shop time tomorrow after work to finish off. I'll definitely use the butane torch in combination with the oxy-butane set - butane torch for as much global heat as possible, and the oxy set to add spot heat for the final soldering; there is a lot of parts that will require heat...
 
 The pickle got a good work-out today - not nice & clean any more!:
 
 
 And the boiler parts so far:
 


28 December 2009

I finished soldering the boiler this afternoon after work. It came out OK with using the 2 torches. A photo of the set-up I used - the 2 torches, with the butane torch positioned to provide background heat, and mixed flux readily located should more be needed (which it was):
 
 
 I assembled everything with flux paste in all the joints, and started heating to do the top first. Quite a bit of flux bubbled away from the joints while heating, so I added more. Then I fired up the other torch to a higher heat, and added it's heat; the flux flowed in short order. Running a circle with the high temp torch around the perimeter, I followed it with the solder rod; worked a treat. To solder the flue to the cap, I just pointed the hot torch flame down the flue, and the solder flowed easily around the joint.
 
 Then I turned everything upside-down, added more flux to the bottom cap joint, brought to heat again, and once again ran a hot ring around the outside following with the solder.
 Two photos; top and bottom of boiler after soldering & quick dip in pickle - all the joints looks sound to me:
 
 
 
 The parts can lay in the pickle now until tomorrow evening; then I'll just do a clean-up.


29 December 2009


I took the boiler out of the pickle this evening after work, and checked all the solder joints. They all visually look sound, so only the hydraulic test will show up if there are defects... I couldn't resist having a quick go at the boiler with some needle files, emery and brasso - nothing fancy & really quick, as most will be covered either in lagging or painted. Far from perfect, but will do for me for now:
 



Regards, Arnold