Friday, 27 April 2018

Another evening run

Another evening run out around Norfolk, some shots from me but most taken and tweaked by John Harris. Find John at

This week, we took a tour around RAF Matlaske, RAF Oulton and the National Trust's first property at Blickling Hall.

Saturday, 21 April 2018

Another lathe job

I made a trip out the other day, with a mate on an MT350, to look at the Dome Trainer at RAF Langham. Great run out, lovely weather and all that, some shots from me but most taken and tweaked by John Harris. Find John at

Back home I found the clamp screw from my float bowl had disappeared - mainly because I had changed the cap for a better one, with a tickler of the correct length to reach the float (!) and hadn't screwed the clamp up at all...

So, unable to find one on eBay and too mean to buy one from Amal (they are over a tenner!), I checked the thread and found it to be 1/4" BSF. Rooting about in the 1/4" screw box, I found an Ariel clutch centre screw which has the correct thread AND the reduced hex head, or something like it, that the real Amal screw has. Adding a small sleeve out of a bit of round bar yielded something that will do the job:

Here it is in place, with the new float chamber lid:

It will do the job until I can find a real one at a reasonable price.

Tuesday, 17 April 2018

Huntmaster Toolkit

As you know, I have a bit of a passion for getting the tool kits right on my bikes. Some while ago, I started a post on the tool roll for the FH, which took a while materialise but the secret to finding these bits is to do your research and start looking, in the knowledge that it might be a while before you find everything...

Here is the toolkit list from the 1956 parts list. Added to this for 1957 is a 'single ended box spanner for rear wheel nuts', number 6601-57, though I am not sure why:

Here's a list I made to collate what I had. Decimal dimensions come from the factory drawings in Ray Tolman's list.:

Ariel PN
Old PN
End 1
End 2
Spanner for brake fulcrum adjustment
Double Ended Spanner
Double Ended Spanner
Double Ended Spanner (rear wheel spindle nut)
Tappet Spanner
Double Ended Spanner
Double Ended Spanner, steering head nuts
9/16" BSW
5/8" BSW
Spanner for sparking plug
Box Spanner for rear wheel
Tube Spanner for hub spindle nut
7/16" BSW
1/2" BSW
Screwdriver for clutch spring nuts
Magneto Spanner
Tyre Lever
Tyre Lever and tommy bar
Tyre Inflator

Single Ended Box Spanner for rear wheel nuts

Tool roll only

My FH tool kit started off looking like this:

A tool box full of spanners
So we need to set to and find the tools. Item 1 is easy, and I already have one for the FH:

Item 1, Brake Fulcrum Spanner
Item 2 is also easy, once you remember that these spanners were bought in by Ariel, the makers names ground off and 'Ariel' stamped in their place. They are also notable for the fact that they are marked with BSW sizes unlike most Ariel spanners, which are marked with BSF or BSC sizes:

Item 2 Double Ended Spanner
Item 3 is another common Ariel spanner, the G1/59. This one is the later oval shank style:

Item 3, Double Ended Spanner
Item 3 is a bit tired and will need some material adding.

Item 4 is a complete guess, supported by Ray Tolman's opinion:

Item 4, Double Ended Spanner
Is this BSA spanner similar to item 5, given the provenance of the FH engine?

Giving it some thought I decided this later BSA spanner would be more appropriate.

Item 6 is one of the most common Ariel spanners. This one is pre-war (rectangular shank style):

Item 6, Double Ended Spanner
Item 7 is also very common, though this one has been filed out...

Item 7, Double Ended Spanner
This one fits the spark plug, but other than that is a complete guess:

Item 8, Spark Plug Spanner
I have no idea what item 9 looks like, or what size it should be. Here's a modern equivalent for item 10:

Item 10, Modern Version
Item 11 is just the usual wire formed screwdriver:

Item 11, Screwdriver
The clutch screwdriver is also easy:

Item 12, Clutch Screwdriver
Item 13 is a standard Lucas magneto spanner, which I forgot to photograph.

Item 14 is a tyre lever, which I assume is similar to either to the 'third hand' type included in the military tool kits, or more probably the Dunlop spoon type. Since I have a spare cranked one, we'll add that for now:

Would item 15 be something like this, used by Triumph?

Here's my attempt, almost there:

So now I have this, and a lot of searching to do.

Here's the repro tool roll I made in this post:

The little pile of tools fits the bag nicely:

And the bag fits in the tool box:

Here are a few links to my other toolkit pages:

Sunday, 15 April 2018

Tommy Bars

Genuine Ariel tommy bars are another rare item, and typically (of the tools at least) are rather confusing - not helped by the aforementioned rarity:
  • 6612-27, Dwg # G1/57 appears in the 1940 singles parts books as a single diameter bar 
  • The W/NG workshop manual shows a dual diameter bar
  • 6612-27, Dwg # G1/57 (yes, the same part number) appears in the 1947 singles parts books as a bar with three diameters. This also appears in several parts books until 1956, so we can assume this tommy bar was now considered a mature design (!)
    • the 1948-1949 twins parts book
    • the 1949 SQ4 parts book
    • the 1953 singles parts book
    • the 1954 Huntmaster parts book
  • The 1956 Huntmaster parts book lists a 'Tyre Lever and Tommy Bar", 6625-55. Parts books (prior to Leader/Arrow) ceased to be illustrated in 1951, so we have no idea what this looks like.
  • Leader/Arrow parts list include tube spanners with tommy-bar holes, but no tommy bar. One assumes that you were intended to use the screwdriver as a tommy bar...
Once again courtesy of a few members of the Ariel clubs around the world, I have these pictures of three examples of the later 6612-27 three-diameter, two step tommy bar, and a W/NG tommy bar from Ray Tolman's genuine W/NG tool kit which has yielded so much interesting information.

Part of Scott Williamson's 1949 SQ4 tool kit

Close up of some of the tools from David Andersen's 1949 VH toolkit
We can see a few interesting points from this last picture:
  • the tommy bar appears to be about 0.375" in diameter and is overall about 7 1/2" long
  • the tommy bar has a section reduced to maybe 5/16", and this is about an inch long. This is to pass through the holes in the various box/tube spanners and the QD wheel nut spanner.
  • the tommy bar has a further section reduced to maybe 1/4", and this is possibly 3/8" long. This is to engage with the smaller box spanners and the hole in the telescopic fork wheel spindle: this is probably the reason this third, smaller diameter was introduced
Ray's pictures give us some proper information. Ray kindly measured these for me and allowed me to share the pictures so we can all use the information.

You'll notice Ray's tommy bars are a little shorter than David Andersen's later tommy bar. Here's a close up of the stepped ends; Ray confirmed that there is a 0.31" section on both bars:

I'm planning to turn each of these up from EN16 steel round bar. First cut two 7" lengths from a bit of 3/8" round bar:

Face and round the ends:

And as if by magic, some tommy bars appear:

Hub Bearing Locking Ring Spanner

This is a rare item indeed, but courtesy of a few members of the Ariel clubs around the world, I have these pictures. I've been using this modern version:

It's mostly fine, but you have to remove that handle to remove the non-brake side retaining ring since it is recessed in the hub and you cannot get the pins (which are 5/32" diameter, by the way, and about as long) to engage safely in the ring.

Recessed locking ring
The one on the brake side is easy - its not recessed at all. Making a replica of the original will make it easier to get the non-brake side locking ring screwed in, as well as completing the tool kit.

We can see from this next picture that the original locking ring spanner is cast. I'm not going to be able to emulate that - I will be making one on the lathe, welding and using the pillar drill. We can see that the disc is not much thicker than one of the pins - the pin diameter is of course dictated by the holes in the locking ring.

Part of Scott Williamson's 1949 SQ4 tool kit
We can see from this picture that the drive pins on the locking ring are very close to the edge of the disc:
Part of David Andersen's 1949 VH tool kit

Close up of David Andersen's tools
We can see a few interesting points from this last picture:
  • the lock ring spanner is about 1.75" in diameter
  • the lock ring spanner has a 0.820" hex - 7/16" BSF by scaling from the picture which will match the hub nut tube spanner
So, the plan is to find a suitable bit of hex bar; then use a slice of 1 3/4" round bar or a bit of 3/16" plate (which I have in stock). I've been thinking about how to make this and I've come up with the following sequence, which will probably get modified as I think more about it:

  1. Cut a rough shape from the 3/16" plate, suitable to fit in the 3 jaw chuck
  2. Fit the external jaws to the chuck, chuck the plate and face one side with a minimal cut.
  3. Flip the plate in the chuck and face the other side.
  4. Centre drill, drill 6 mm, open out to 10 mm and then 13 mm. Bevel the hole slightly.
  5. With the plate still in the lathe, mark off the PCD of the pin holes.
  6. Chuck the 0.820" bar and face off.
  7. Turn a journal to an interference fit for the 13 mm hole and to a length equivalent to the thickness of the plate.
  8. Bevel side first, push the plate onto the journal using the tailstock to keep it square.
  9. Saw the 0.820" bar to a suitable length - about 0.5"
  10. Put the hex in the face with the flat side of the plate upward
  11. Weld the plate to the journal
  12. Put the hex back in the 3 jaw and turn the face flat again, dressing the weld
  13. Turn the plate to a suitable diameter
  14. Round the side of the plate with the hex
  15. Ensure the PCD of the pin holes is still clearly marked.
  16. Flip the plate in the chuck and face off the hex; bevel the edges.
  17. Drill the pin holes somehow... ideally indexing in the lathe and using a tailstock drill?
  18. Use the tailstock chuck to push the pins in square
  19. Test
  20. Paint
Step one, saw out the plate:

Almost there
Step two, change the jaws of the 3-jaw chuck for the external jaws, and chuck the plate. Then clean up the face with a minimal cut:

Step 4, centre drill the plate:

Next step, drilling the hole 6 mm, then opening out to 10 mm and then 13 mm. I managed to stall the lathe for the first time!

The plate prepared for welding, and the hex cut to length to go in the lathe. The 0.800" hex does not fit through the chuck...

Step 6 done, and the beginning of Step 7: turning a journal for the plate to fit on.

Step 8, the two parts together:

Step 11, welding. Remembering that the only hex bar available is EN1A, it's no surprise that the weld is porous. I'm not sure what the plate is, but that is probably EN1A as well...

Step 12, facing off shows the porosity nicely...

Step 13, turning the plate to a suitable diameter - part way through:

Marking the pin pitch circle diameter:

Ready for drilling:

Some of those voids are actually in the 1/4" plate. Great quality steel...

Dykem applied, ready for marking out:

Before we start machining the holes, we have to set the lathe up for milling. this involves removing the compound slide, bolting down the adapter plate and fixing the vertical milling slide to the adapter plate.

Before we start, we have to make sure the milling vice is perpendicular to the spindle axis. We can do this with a piece of round bar in the chuck, and a small square to set the vice up to the axis.

To drill the six holes at 60 degrees to each other, we need to index the disc. I'm indexing on the hex, welded to the back of the disc - I machine one hole to 5/32" deep, index, then machine the next.

When I've drilled all the holes, I cleaned up the disc with emery. The pins are 4 mm dowel, which provides a slight interference fit on the holes in the disc which are drilled 5/32" (about 3.96 mm) - they are pressed in place in the vice with Loctite 243 (medium strength threadlock - not very appropriate):

The holes in the hub locking rings are flat-bottomed. To provide maximum engagement, I ground the ends of the pins flat:

Next job is to turn the tool to the proper diameter, but first I need to test it:

It's not too bad, but a quick test reveals that I must deburr the pins.

Now finished. The hexagon and the disc have been turned to shape to mimic the cast original, and I have deburred the pins.