| Drawing E1- Bogie |
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1. Bogie Frames |
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These are the second set of laser-cut frames
and were set up in similar fashion to the main frames. Someone privately
queried my term "tee-slot packers" and this photo shows the complete set-up.
The packers are a tight fit in the slots and, although they don't look it,
are very accurate. If I wanted to clock the edges after removing the packers,
I would expect to see no more than one thou deflection. DY has given hole
sizes for the horn cheeks that seem to indicate rivets should be used. The
horn cheeks on Calbourne are afixed with bolts, nutted on the outside. Therefore,
I will fix mine with 10BA bolts and have resized the holes on the drawings
accordingly. The stretcher-fixing holes have been drilled 3.0mm diameter
and I'm countersinking to suit M3 screws. I prefer to use a drill, ground
to 90 degrees, rather than proprietary countersink tools because I can control
the amount of backing-off. The slight chatter in the holes is deliberate,
it aids pulling the screws up tight. |
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These are the finished frames and you might notice an
extra hole either side of each horn cutout. Because I will be using 10BA
screwd to hold the horn cheeks in place, I have added a 3/32" dia dowel-pin
hole to help keep the horns in place. Two per unit would have been ideal
but space is a little tight here. I slipped up by not looking ahead when
I made the bogie stretcher, tapping 6BA fixing holes. I have redrilled the
holes 2.5mm diameter and overtapped the threads with M3. The metric countersunk
socket screws are considerably cheaper than the 6BA ones. |
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2. Bogie Stretcher |
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The bogie stretcher is an assembly of parts that also
supports the pivot block. I started with a ragtag collection of offcuts
to fabricate this item. I tackled the side support plates first and decided
straight away to make a few changes, re-dimensioning the drawing to give
distances from a centre-top datum point and adding extra holes to allow
the assembly to be screwed together with 8BA countersunk screws. The plates
were milled all round as a pair then drilled separately in the mill. It's
much easier to work to a set of plus and minus dimensions from a central
point. On the drawing, the top of the drawing is actually the bottom of
the stretcher. |
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The various cross pieces were then machined top and bottom
as a group to ensure they were all the same width (with respect to the stretcher)
before milling each to their respective lengths. With the top and bottom
plates cleaned up all round, attention was then directed to the cutout for
the pivot block. The centre of each plate was set on the DRO and four 4mm
holes drilled in the corners, leaving about ten thou each side and end for
finishing. Using plus and minus 0.406, 0.906 as my co-ordinates, a 4mm dia
carbide end mill was used to remove the centres, plunging in 25 thou per
pass and winding round each side in turn. |
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With the centres of both plates milled away, They were
mounted on edge in the vice and the 8BA holes drilled and tapped to match
the side plates, 1/8" down from the top and 1/8" up from the bottom Then
the four components were assembled to make the basic stretcher. The module
was mounted side-on in the vice and the lower cutaways milled with a 1/4"
end mill, touching on the end to set the "X" datum, then taking four lots
of sixty-thou cuts to finish at 0.625" from touch-on. On the left-hand side,
I tried climb-milling but it kept grabbing the work so worked outwards from
0.625" instead. The radius of the corners is not given on the drawing but
a 1/4" end mill sat nicely on the drawn form. Next up was the large radius
cutouts in the top plate and, after much head-scratching, decided to add
an extra hole in my home-made flycutter and use this to get the size. The
shank of the boring bar is 8mm and the cutting diameter worked out at 0.376"
so a hole was drilled and reamed 8mm diameter at (1.750 - 0.188 =) 1.562"
from the centre. Then it was held vertically in the vice and an M6 tapped
hole put in for a clamping screw. |
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With the tool loaded up and set on the centreline of
the work, multiple passes were taken on the "X" axis using 25 thou depth-of-cut
each time, finishing when the tool was just starting to kiss the side panels.
This was set as the zero datum and a final plunge-cut at X-5 thou taken
to clean the face. At this diameter using high speed steel, one would expect
to use a cutter speed of about 150 RPM to avoid an excessive surface speed
burning the tool but carbide is quite happy at about three time that and
420-450 RPM was used. Much easier to control at that speed. With the ends
shaped as drawn, the final job was to machine the top and bottom recesses
for the top flange of the pivot block, it's retaining plate at the bottom
and the final size of the width of the block itself. It is important that
the two recesses are exactly in line and the module was marked accordingly.
The lower plate was machined first, using the centre of the module as the
X0, Y0 co-ordinate, then the inner section milled at plus and minus 0.416"
for the sides and 0.917" for the ends. This was for a 4mm solid-carbide
end mill. |
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To mill the recess, the tool was zeroed on the top of
the work, then three roughing passes and a finish cut were taken, winding
round on plus or minus 0.616" and 0.917" for the final cut. The module was
then flipped over side-to-side only to ensure alignment, zeroed on the centre
of the "X" axis as before but keeping the existing "Y" datum. The process
was then repeated for the top face using exactly the same set of numbers.
Using a centre datum pretty much eliminates the chance of errors. The section
drawing at the top shows internal sides to the pivot block channel but these
are not really needed and I have decided to dispense with them. This whole
module is encased within the bogie frames and nothing can be seen once it
becomes a complete assembly. With the outer radii linished on, this is how
the finished stretcher looks. If I decide to silver-solder the module together,
the countersunk screws will keep everything in the correct place. |
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3. BogieBolster |
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The bogie bolster sits beneath the frames and is held
in place with a pair of angles. The main plate is 3/16" thick and a piece
of mild steel plate was cleaned up all round and the faces dressed to size.
The plate was then held in the vice on packers, the DRO zeroed on the centre
and all the holes drilled for the support angles. The centre hole for the
kingpin was drilled and reamed 3/8" diameter. The support angles were cut
from a piece of 1/2" x 1/2" x1/8" angle and faced to length in the lathe,
held as a pair in a 3-jaw chuck. |
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The faces were cleaned up with a rub along some emery
cloth and the rivet holes were then drilled in a single pass using a PCB
drill using the fixed face of the vice as the reference position. The angles
were flipped over and the bolting holes drilled and tapped 6BA. ] Finally,
the angles were riveted onto the plate. Although DY specified 1/8" rivets,
I have chosen to use 3/32" iron rivets. These are plenty strong enough for
the job, look balanced and, anyway, 1/8" rivets would have been difficult
to fit with the heads close to fouling each other. I've noticed a few places
where DY seems to have gone OTT, if built exactly to drawing this loco would
be like the proverbial brick s**thouse. |
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4. Bogie Stays |
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The two end stays on the bogie look to be quite flimsy
affairs and I made mine from some 5mm thick gauge plate that was in the
box. Cutting two strips from this, by hand, using a hacksaw took longer
that all of the machining put together. After cleaning up the edges to finish
at 7/16" wide, I trimmed them to length by loading them together in my small
milling vice and passing a cutter either side. It was easy to get them identical
and bang-on size this way. Keeping them together as a pair, the centre sections
were removed from the first side with a 12mm end mill, starting in the centre
with a 25 thou DOC and working outwards with 10mm wide passes until the
ends were 3/32" wide. For the other side, I milled up a special packer to
set it as deep in the vice as possible and repeated the exercise. |
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With the milling complete, they were upended in the vice,
one at each end, resting on 1/16" packers. This was then removed and the
fixing holes drilled with a PCB drill. The drawing shows them to be 3/16"
wide but I left mine at the original thickness of 5mm. The extra five thou
each side doesn't foul anything so it's not worth milling this down. |
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5. Pivot Block and Kingpin |
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The drawing suggests a gunmetal casting or bronze but
there is nothing wrong with brass in this application. Unfortunately, I
had nothing large enough to make this from a single billet so resorted to
using offcuts once again. The round billet was faced off and a 3/16" long
spigot turned on it 3/4" diameter and I also drilled and bored the 9/16"
diameter kingpin hole. The 3/16" thick brass plate offcut was milled all
round to leave a rectangular section 1.3/8" x 1.1/16", a slight change from
the drawn size. Then a 3/4" hole was drilled and bored in this plate and
the two parts silver-soldered together. In my enthusiasm, I forgot to take
a picture at this stage. The assembly was loaded to the mill vice and the
thickness reduced, equally both sides, to finish at about 1.050", not particularly
important because it serves no useful function. The drawing shows 1.125"
but my plate wasn't large enough for this. |
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The next stage was to bring the sliding surfaces to somewhere
near size and equally-spaced either side of the hole. The billet was supported
on a near-size bar of mild steel and the outer faces milled, cleaning up
one face, flipping it over and cleaning the other face at the same setting.
After measuring, an equal amount was take off each side, aiming to finish
at an overall size of 1.372". Then the narrower section was roughed out
using the same technique but leaving both the shoulder and the width oversize.
With the relative positions of the faces and the hole fairly accurate, it
was easy to finish the width by loading to the vice orientated to the top
face. With the fixed jaw being "Y0", the shoulder was reduced to 0.130"
( another modification on my part) and the width reduced to a couple of
thou under the inch. |
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To clean up the underside of the flange I used an end
mill on the same setup, finishing the thickness at 0.125". Then I went to
the lathe and loaded the billet to the independant 4-jaw chuck, clocking
true on the bore. The tape is sufficient to prevent marking of the body.
I've only just nipped this up lightly, the shoulders rest against the chuck
jaws and it can't go anywhere! A round billet can spin in the chuck, not
so a square item but people still tend, unneccessarily, to pull the chuck
up tight. Thirty thou was skimmed off the face to leave a bearing surface
for the underside of the bogie bolster. To stop the bogie dropping on my
foot when the loco is lifted, it requires a clamping plate underneath. This
was cut from some 14swg brass sheet, milled to 1.375" x 1.050", four fixing
holes drilled and the centre hole drilled out to 9/16" diameter. Matching
6BA holes were drilled and tapped into the bottom of the block and I also
machined the pockets for the side control springs using an 8mm slot drill
but didn't bother to take a photo of this. |
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When I first bolted the plate to the bottom of the block,
it locked up tight in the slideway. The block was put back in the vice and
an extra five thou removed from the underside of each flange. After that,
the block slid freely, but not sloppily, along the channel.The kingpin,
or pivot pin as it's called on the drawing, is relatively simple turning
and I made mine in a single operation. An offcut of 1" diameter mild steel
was turned in stages, starting with the mounting pin and it's thread. I
don't have a 5/16" x 32 tpi button die and don't see the need for a fine
thread so M8 x 1.25 was used instead. Then the body of the pin was turned
to 9/16" diameter but I shortened the length to fifteen thou greater than
the length of the pivot block and it's retaining plate. With the head of
the pin turned to 7/8" diameter, the pin was parted off. |
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And then I realised that I had forgotten to drill the
oil hole through the centre. All was not lost, though, and the pin was set
in the bottom of the vice and held with a pair of vee-blocks resting on
the shoulder. From here, it was easy to find the centre and drill the 3.2mm
diameter hole to a 1" depth. To drill the cross-hole, I flipped the blocks
over sideways and eyeballed the middle of the pin. The "Y" axis position
stays the same, of course, so I was confident of hitting the hole down the
middle. It certainly beats making a sleeve to hold the pin in, especially
as it's a slightly unusual size and unlikely to be used again. |
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6. Equaliser Beam |
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The sides of the equaliser beams are the final laser-cut
parts and are as accurate as expected. There are only two holes marked out
on each for the spring hanger support pins. DY also does not show separately
the support blocks that rest on the axlebox, nor suggest a method of fixing
them. I started by milling a length of 1/2" square black mild steel down
to 7/16" square so that I could hold it in my 4-jaw self-centering chuck.
The raw material was out-of-square so, for the second cut, I used a round
bar to push the first milled face against the fixed jaw to guarantee squareness.
The round nipple that sits in the axlebox dimple was the first lathe operation,
turning the front to 5/32" diameter by 1/8" long. You will see one of my
expensive safety devices in use here: a length of sparky's tape covering
the key holes of the main chuck. Only once have I undone the wrong chuck
and dropped the 4-jaw onto the bedway. |
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The small radius was machined next using a form-tool that
had been free-hand ground, then lapped with a piece of 4mm rod and grinding
paste. Not a very good picture, I'm afraid. Parting off was achieved using
the standard fallback method. I generally have no concerns about parting
off but even I baulk at parting off square material held in a chuck, held
in another chuck on an eighty-year-old lathe with dubious bearings and a
cross-slide with lots of backlash. After cutting off, they were returned
to the chuck, up against a backstop and faced to 19/32" long. To fix the
blocks into the frame, I've chosen to drill four cross-holes and hold them
in place with dowels and then silver-solder them. This guarantees that the
nipples are square and bang-on 5" apart, to suit the axle boxes. A backstop
was set on the vice and the blocks centre-drilled and drilled in turn. |
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The beams themselves were mounted the same way as the
frames and bogie frames, all four at once, the centre found and the "X0"
and "Y0" reference points set. Two of the frames have a 5BA thread and two
have a 1/8" reamed holes. I drilled through all four at the tapping size
and opened the larger two separately later. I also made the four spring
hanger pins from some 0.195" (6BA) hexagon mild steel, of which I seem to
have quite a lot. I have added all my own detail to the drawing for future
reference. Prior to all this, I searched for some 3/32" rod to act as dowels
but couldn't find any, and my rivets were all too short. However, a tub
of galvanised nails provided a suitable sustitute and a handful of these
were dropped into citric acid to remove the zinc. They turned out to be
2.7mm diameter and this is what the holes were drilled to. The beams were
assembled with the pins in place, the support pins holding everything together
and the offcut from the 7/16" material used to support the middle. Silver-solder
horseshoes were made and placed at the edges and the area well-fluxed. |
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I also added correction fluid around the threaded parts
to protect the threads from scorching. They were set up in a hearth and
heated till the solder flowed, getting some heat into the centre first,
followed by each end. This picture was taken very shortly after completing
the second end. Once cooled, they were placed back in the pickle to clean
off the flux and then the pins were dressed back to flush on the linisher
although, when they were nearly flush, I did give them a good belt with
a hammer to mushroom the heads a little. I could see silver-solder around
the ends of the pins so I'm confident of a good melt. After a general clean-up,
this is the end result and they can now be phosphated. |
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7. Spring Brackets and Buckles |
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The two bogie spring brackets fit to the side of the bogie
frames and support the spring buckles. I was able to use the two offcuts
that were milled from the top and bottom plates of the bogie stretcher.
After milling all round to get the finished rectangular dimensions, the
cutouts for the buckles were removed first, stitch-drilling then milling
with a 4mm carbide slot drill. The ends were milled away next to leave the
side legs for fixing to the frames. I chose to mill mine vertically because
it kept more material within the vice. Just holding on the baseline with
about 3/32" in the jaws is probably asking for the work to climb out of
the vice. |
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The two fixing holes and the hole for the buckle support
pin were drilled next. The centre hole was drilled 4.1mm to match the support
pin which I have changed from 5/32" x 40 to M4. The support pin was turned
from 6BA hexagon stock. These are the finished parts. |
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I had run out of suitable square material so the spring
buckles were made from a couple of billets of 5/8" diameter mild steel,
parted to 1.031" long and milled down to 7/16" square. The rectangular end
sections were formed next, using a backstop on the vice to control the length. |
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Being careful to get the orientation correct, they were
reloaded to the vice on a packer, the packer removed and the cutout for
the leaf spring stitch-drilled. Then a larger slot drill was used to clear
out most of the centre section and the sides finished with a file. I still
need to complete these because my 1/4" square file was skidding all over
the place and has now been binned (minus it's handle) and I'm waiting on
a new one to arrive. |
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8. Bogie Horns |
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I have made the bogie horns from eight blocks of bronze
and, as usual, the first job was to cleanup all round and finish the outside
dimensions. The lower sections for the horn keeps were milled next with
a 12mm end mill. Using the bottom of the horns as the reference, they were
loaded to a backstop and the waste between the webs removed. The form was
followed round about ten thou shy of finished size, then the upstand removed,
followed by a final pass around the perimeter. |
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The drawings shows the webs as 1/8" thick but that looks
way too chunky so the central webs were machined to 3/32" thick. I machined
the four left-hand horns first, then reset the "Y" datum to make the right-hand
ones using the same set of numbers. |
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The various holes were done next, including the blind
3/32" dowel hole which I made 1/8" deep. This is a modification that I have
made to give additional support, the drawing has holes sized for rivets
but I'm using 10BA bolts. Checking with a 10BA bolt in a box spanner, the
heads of the bolts were riding up the radius at the bottom of the central
web so a long-series 6mm end mill was used to sharpen the internal corners.
The lower web was fine. |
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I used three different methods to machine the various
angles. For the top of the bolting face I used a twenty degree angle gauge
against a stop and a pin through one of the holes to set the height. For
the lower web, I used a small vice mounted on an angle table and ran carefully
into the small void at the end. |
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And for the web in the middle, I mounted the horns directly
to the table with a backstop and clamps. It was the only way to get clearance
with the kit I've got. These are the eight horn cheeks and the camera shows
every machining mark although they are actually quite flat and smooth. I
will give them a session in the sand blaster to dull the surface but these
will be primed and painted later. |
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9. Bogie Axle Boxes |
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I've changed the design of these because I have decided
to use bronze liners for the bearings and thrust faces. Therefore, I have
made the axleboxes from 1" square mild steel rather than cast iron
or gunmetal. After facing to 1.1/32" long, I machined the bores next, using
an independant 4-jaw chuck. Because the bores are offset in the block, I
set up the mill so that I could use a centre drill to give me something
to clock to. The blocks were drilled 1/2" dia, bored out to 0.580" dia and
finished with a 19/32" reamer. I also machined a 3/4" dia recess 1/16"
deep to take a thrust washer. With all four done, they were reversed in
the chuck, clocked true and the outer rubbing face machined. The horn guides
were machined next, roughing all the blocks out first with a 12mm end mill
and leaving the faces five thou proud. The "Y" axis was set to 0.500" from
the fixed-jaw face and remained at that setting for the rest of the operations.
A second pass either side of plus or minus 0.130" at the same depth brought
them close to finish size. With all eight channels roughed out, the blocks
were returned for a final pass either side to leave the finished width of
0.750" and 0.687" across the faces. |
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The pocket for the nipple of the equaliser bar was done
next. A backstop was set on the mill, the current "Y" axis position kept
the same, the "X" datum set to the centreline of the axlebox and the pocket
drilled with a centre drill. Over on the lathe, the axleboxes were trued
up to the centre so that I could machine the top face to size, leaving the
upstand. With the tops completed, it was back to the mill, reload the work
to the stop and finish the dimple to depth with a 4mm ball-nosed slot drill.
The next picture shows the form of the pocket which had been shaped with
a fifteen-degree plunge tool. |
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The two final ops were to reduce the width of the front
flanges to 15/16" and the rear flanges to 7/8", although the rear ones will
be reduced again once they are fitted to the horns. These were a simple
pass of the end mill down the left-hand side and back up the right side.
Finally, the bronze Glacier bearings were pressed into place. The finished
boxes will now be stored until I've finished the horns, then will be tweaked
to fit. |
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10. Bogie Axles |
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The bogie axles are made from 3/4" dia mild steel and
I cut a couple of billets 7" long. Using a backstop, I faced and centre-drilled
one end of each axle. The I roughed out the two journals, leaving about
twenty thou on the O/D, but facing the two shoulders to finished length.
Run-out doesn't matter here. Then they were turned round, faced to length
and the first operation repeated. The next job was to relieve the centre
section of the axles and each one was loaded up against the jaws and, working
from the middle, the material reduced to 1/2" diameter with multiple passes
to the shoulder, allowing for the radius. |
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Then the tool was changed over for a radius tool and
the shoulders formed. With both ends done, the join in the centre where
a slight run-out witness remained was polished out with emery cloth. The
tool is 3/8" square tool steel freehand-ground to a radius gauge. With the
wheels finished, I was able to machine the journals to size. A piece of
mild steel was machined to 60 degrees inclusive to provide an accurate front-end
centre, a driving dog clamped to each axle in turn and the two journals
machined at the same and a live centre to support the back-end. On my lathe,
the compound slide needs to be turned round to about sixty degrees and the
toolpost re-alligned to allow me to get in close to the live centre. These
are now ready for assembly. |
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11. Bogie Wheels |
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A colleague had four wheels from an abandoned project
that he thought might be suitable for Calbourne and it appears that the
hub, rim and spoke profiles are correct for the loco. They are cast stainless
steel, which I'm a little apprehensive about but he has already done some
roughing out and assures me they machine quite well. I will need to sleeve
the bores but the rest of the work should be stock removal only. Everyone
has their favourite way of holding wheels for the various turning operations,
mine is to use soft jaws bored to suit whatever diameter I'm wanting to
hold. I made up a new set of jaw blanks, numbered them and then bored them
to suit the turned diameter on the wheels. |
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I started by holding on the backs and facing the boss
to get the right shape and size, then faced the front of the wheel a further
1/32" in and took a light skim over the top ready for the second op, repeating
with the other three wheels. Then the wheels were reversed and the backs
faced to finished width, the outside diameter turned to 3.300" and a nice
little radius machined on the outside edge. The boss on the back was also
removed on this operation. The jaws were wound in and a new register machined
at about eighty thou deep and 3.300" dia to hold on the newly-turned flange.
The tread section was then roughed out, leaving about fifty thou on the
flange face and about the same on the diameter. Then a radius tool was used
to face the flange to 0.100" thick, the tread diameter to 3.010" and leaving
a nice radius in the root of the wheel. |
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Three further operations were done to complete the machining
of the wheels. First, the compound slide was set over to two degrees and
the treads coned with the tool running off just before the wheel root. The
second was a chamfer to the outside of the tread and the third was to bring
all four bores to 0.625" diameter, ready to accept a sleeve. The only job
I couldn't do in these jaws was the radius at the inside top of the flange
and the wheels will be loaded to a mandrel to machine that. The rest of
the work on these wheels was mainly concerned with machining away material
to end up with the correct profile. First of these was the radius at the
root of the spokes where they join the hub. Prior to this, though, I had
machined all the bores out to 0.656" ready to take the insert. A section
at the back of the hub needed to be cleared from the spoke root and the
lathe chuck was mounted on the mill table for this. A 5/16" diameter end
mill was used, aligning each gap by eye and plunge-cutting twenty thou at
a time until a slight witness appeared on the hub. The table was left unlocked
so that the endmill would find it's own centre on the final couple of cuts. |
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Back to the lathe and the rear of the hub needed cleaning
up. The same radius tool was used for this but work-holding was a little
less secure because of the chamfer on the front of the tread and the intermittent
nature of the cut. A dead centre held by a live centre was used to stop
the work popping out of the jaws but allowing me to get the toolpost nearer
to the centreline. Inserts were made from some 3/4" dia stainless steel,
turned to 0.657"-0.658" for a decent interference fit. I left these thirty
thou overlength and also drilled a 3/8" hole through them. The chap at my
local garage pressed them in for me using their hydraulic press. I wasn't
allowed to go through (H&S) but he told me they took 22, 24, 24 and 28 tons
pressure respectively to get them home so I don't expect them to fall out.
Back on the lathe, the bore was opened out to 0.425" and a 7/16" reamer
pushed through. Some work with the file and Dremel and these are finished
and ready to push onto the axles. |
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12. Completing the Wheelsets |
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The bearings have now been pushed into the axleboxes and
the oil holes drilled through. I used a smear of loctite retainer to help
keep them in place. I've also made a small modification to the wheels and
axles. Quite a few times I've read of others having the occasional wheel
come loose and have decided to use locking screws to keep mine in place.
In the back of the wheels, I have drilled a twenty degree hole using the
tilting vice. These have been tapped M4 and cup-point stainless steel grub
screws will be used. After lightly tightening one screw to get a mark, I
then undercut each of the axles with a 20 degree tool to leave a pocket
for the screw to land on, This stops the screw raising a high spot on the
axle and hampering future removal. It also has the advantage of pushing
the wheel firmly back onto the shoulder of the axle. The wheels themselves
are a very light press fit. |
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Finally, the axleboxes were loaded to the shafts, the
wheels pressed on, screwed up and the ends of the axles faced off. The travelling
steady that I made the other day was used to support the outer end of the
wheels. The wheelsets are now complete and can be put aside until assembly |
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13. Spring Hangers |
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The drawing shows four spring hanger to be made but, because
I'm making leaf springs for the driving axles also, I have made twelve of
them, plus a couple of spares. Rather than machine the whole thing from
solid, I have chosen to silver-solder the pivot tubes on to the hooks. Using
5/16" square mild steel, the first job was to drill a 3/16" diameter crosshole
5/32" from the end. The vice jaws also act as a backstop. Having a second
milling machine, I was able to set up a sort of production line and, after
cutting through the end of the hook, the upper arm was made by milling away
an equal amount either side with a 3/16" end mill. |
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Metal was sawn away from the bottom of the front slot
into the cross-hole, leaving the basic outline of the spring hook. This
was followed by a session on the linisher and with files to finish the profile
of the hook. |
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I had about a foot of 7/32" dia steel tube, a relic from
a job in the distant past and which had a conveniently-sized bore of 1/8",
and this was used to make the support tubes, parting them off at 7/16" long.
By using the frontstop in the front of the toolpost, they were all exactly
the same length. I made a small jig to assist with soldering the parts together,
basically a pair of 3mm pins and a screw to push the parts together. The
front pin was cleaned and (re)coated with correction fluid after each one,
the parts loaded as in the right-hand picture, and a short length of solder
placed on the join. Heat was applied from below until the solder flowed.
The lower part of the picture shows the item after it had cooled a little. |
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| These are the fourteen hooks cleaned up and ready to assemble.
I won't bother removing any excess solder because most of the hanger is
buried in the equaliser beam or, in the case of the drivers, the spring
hanger blocks. Just the springs to make and the bogie assembly can be finished. |
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14. Next Item... |
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