Landships II

TinCanTadpole · Legend

RE: Commer House ambulance

d_fernetti · Hero

Here is an useful shot of the swing arm brake:
http://www.flickr.com/photos/28439790@N03/4589619220/sizes/l/in/photostream/

(BTW I'm getting to know a lot of new technical terms researchig this) A similar rod goes from the other side of the chassis:

http://www.flickr.com/photos/austin7nut/5679513318/

�

The previous picture of the rusty rear axle is from a Commercar fan website from New Zealand: http://www.commer.org.nz/Commer_Connections/DerekHaycock.html

�

...and this is where I asked for info about the wheelbase. Still awaiting an answer...

BTW, found a website describing some 1909 bus chassis with a wheelbase of 7ft6in... would this be the same with the RC 4 ton chassis adequate to the Horse ambulance?

TinCanTadpole · Legend

7ft6in doesn't sound long enough to me (it's roughly 2.3m) and looking at the pics I think the yellow 'hotel bus' and the horse ambulance are longer than that. Maybe 8-9ft would be closer, at a guess. It's unfortunate that we only have el caballo�to compare the size of the ambulance with - it's easier to gauge against people.

Nonetheless, you've turned up a couple of handy photos with that 'hotel bus': the rod I had wondered about reaching the gearbox is clearly the brake linkage. There's one on each side, interconnected by a shaft and operated by the handbrake; unless this handbrake is interconnected with a foot brake, which I suspect is not the case, then it appears that the handbrake is the only brake, and that it only operates on the rear wheels - it's a good thing trucks were slow in those days!

Coming back to the gubbins under the truck, it seems a bit clearer now. The sloped rod is the brake linkage, running just outside the chassis rail; towards the front is a step to ease entry to the cab; and there seems to be a guard rail on each side that slopes down, then bends to run horizontally and disappears somewhere in the underexposed murk (or behind the ramp). There are a couple of stays hanging down for this guard rail, and it looks like it hangs from the chassis rail; it doesn't feature on the hotel bus.

d_fernetti · Hero

Good observations... I'm taking notes here and there. BTW the New Zealand website has nifty diagrams of the clutch and the gearbox... but fails to show a general arrangement that would have been priceless to depict the underside of this vehicle... maybe I should keep content on just making a "curbside" model of the Commercar? No fun in that!
BTW I also discovered a detail missing on the original magazine article plans: each Commer radiator shell was secured with three countersunk bolts at each side. These indentations are visible on the side view of the "late" model ambulance.
D.

d_fernetti · Hero

That's true, I quoted the sizes as given. Growing up thinking in decimal metric measurements, it's very hard to me to actually "think" in Imperial units, just know by heart the 1' to .254 equivalent from my schools days!
Horses should be standarized, that would help greatly!

-- Edited by d_fernetti on Thursday 7th of June 2012 11:35:02 PM

TinCanTadpole · Legend

d_fernetti wrote:
Growing up thinking in decimal metric measurements, it's very hard to me to actually "think" in Imperial units, just know by heart the 1' to .254 equivalent from my schools days!
Horses should be standarized, that would help greatly!

�The Germans invented metric horsepower; perhaps they know something about standard metric horses� smile

I was born and raised in Britain, where older imperial measurements live on alongside newer metric ones. I use both, depending on which seems more 'appropriate' for the task at hand; generally I prefer to use metric for weights, fine measurements and fluids, but imperial for speeds, distances and dimensions of vehicles. The only metric measurement I object to however, is the ridiculous "litres per 100km", which requires a good deal of translation before it makes any sense to me.

�

PS - don't forget that 12ft 8in/ 3.86m is not exact. Hopefully it's close enough for your set of plans though.

-- Edited by TinCanTadpole on Thursday 7th of June 2012 11:56:54 PM

TinCanTadpole · Legend

If you mean the three vertical grooves towards the top of the radiator side, then I see the marks you mean. If not those, I'm unable to see the indentations.
I still need to have a look over that Commer website, but I've done some slightly unscientific measuring of the photo of the ambulance with the side ramp raised; it's almost exactly side-on, so my measurements shouldn't be too inaccurate for estimating the length of the wheelbase, which is approximately 12ft 8in long. I arrived at this figure by measuring the length of the wheelbase and the width of the side ramp straight off the screen, then using the figure of 7ft 6in for the ramp width - quoted in one of the early posts, which I've just read again.

d_fernetti · Hero

TinCanTadpole wrote:
If you mean the three vertical grooves towards the top of the radiator side, then I see the marks you mean. If not those, I'm unable to see the indentations.

�I meant just those. Inside the grooves there's a bolt head, or a nut.

About the maesurement... Sorry, I'm� metric! 12ft. 8' are then equivalent to 3.8608m, which sounds right-o, old chap (how long was a horse back then?) It sounds more adequate than my previous wheelbase quote.

Off to the drafting table again!

D.

TinCanTadpole · Legend

How long was a horse? Haha, much the same length as today, I expect. Unfortunately horses are normally measured in height, not length; I think a typical height for a horse is 17 hands, which is 1.7m - one hand = ten cm. Actually, that might be the height of a large horse: horse height is measured to the top of the shoulder, and 1.7m means that would be about eye level (an a man) - does that sound like a big horse or a typical size?

I considered adding the metric for 12ft 8in, but left it out because you had been using feet 'n' inches in previous posts. It occurs to me now that you were quoting sizes you'd read, so it made no sense to convert them.

d_fernetti · Hero

Here's a retouched picture of the weird "fence" under the Commer chassis. It's originally from a bus preserved in a collection in the UK, and I'd love to know "where" and "who" as it seems like it has the same chassis than the ambulance, and thus, a first hand source to some measurements I lack.

Anyone has a clue why they put this fence? Just to protect the exhaust pipe?
D.

TinCanTadpole · Legend

I'm guessing there's another section to the linkage, hidden behind the chain in the photo. There's something visible around there, which may be a linkage or may be just shadows and oil stains on the ground - it's not clear.

If it is a linkage I see, then it looks like the lever hanging down (that the long rod connects to) is actually an upside-down V shape, with the rearmost arm of the V connected to the lever on the brake housing. Have a look and see what you think, but I'm not convinced by this possibility: I think part of my V-shaped lever unit is actually an oil stain on the floor.

Mystified by where that linkage goes, but at least you can see more details, like the mountings from which the "middle" axle (the one that drives the chains) hangs.

I must say that with Macks and these Commers, I've gained quite a liking in the last few months for early trucks - Model T aside, trucks somehow seem too modern and boring now if they don't have solid tyres� smile

-- Edited by TinCanTadpole on Tuesday 12th of June 2012 02:23:42 AM

Great War Truck · Brigadier

I think that one lives near Leicester. I have a better photo of it somewhere. The fence you refer to is actually to strengthen the chassis, a bit like the Peerless.

Tim

d_fernetti · Hero

I see... but this structure has crossbeams across (and beneath) the chassis or it's just bolted to its sides?

Great War Truck · Brigadier

I think this bracing only appeared on the 3 ton Commers. The 30cwt ones did not have it. It is fitted to support the chassis from longitundinal movement.

I�am still looking for a better photo but appears to have been fixed in 5 places on each side of the chassis. No evidence of any sideways bracing, but that would not be the weak point. Hope that makes sense and i will look for a better photo.

Tim

d_fernetti · Hero

Whoa! Great pic... looks very similar to the ambulance chassis fixture... and it shows where it slopes upwards just after the drive gear... The sape of the cab floor (which is wider than the chassis beam width) is very useful as well... I was going to improvise in my drawing!

TinCanTadpole · Legend

Another interesting thing with GWT's pic is that the brake linkage stops around the front chain sprocket, unlike that old Commer axle D found on the NZ Commer site, which has the lever mounted on the brake housing.

d_fernetti · Hero

That's odd. How it's supposed to operate the brake drum from such a distance?

d_fernetti · Hero

The inverted V shaped lever is a possibility, although, as you say, it's a bit contrived solution. Maybe later we can know for sure. By the time being,however, here are a sample of the miseries of my work-in-progress drawings, and the kid of notes I take to later draw more accurate details. Some (like the brake lever) might have their own scrap view, as some of the details might end lost in a GA drawing. For the time being, I won't make a definitive chassis drawing, as I keep discovering new details to add to the basic chassis beams.

TinCanTadpole · Legend

Check the height of the ambulance section D, I believe it should be much lower. The height above the cab roof is approximately one third of the height of the cab - not much more. Remember also that the rear wheels are wider (I think - need to check).

Apart from that it's coming on nicely - do you do much technical drawing?

d_fernetti · Hero

Yup, you're right about the proportions of the lorry body... Must revise that. I based the preliminary draft in the magazine drawings, correcting as I go. The width of the chassis beams is also suspect.
The rear wheels were double, of course, but the exterior pair matched the track of the front ones. I need to draw the inner ones, as soon as I get some clues on the transmisson casing widht... then it all will click into place

Not much technical drawings... just learned on the secondary school and always enjoyed it. I was eager to try my hand it it again and this project is fun!

TinCanTadpole · Legend

d_fernetti wrote:
Yup, you're right about the proportions of the lorry body... Must revise that. I based the preliminary draft in the magazine drawings, correcting as I go. The width of the chassis beams is also suspect.
The rear wheels were double, of course, but the exterior pair matched the track of the front ones. I need to draw the inner ones, as soon as I get some clues on the transmisson casing widht... then it all will click into place
Not much technical drawings... just learned on the secondary school and always enjoyed it. I was eager to try my hand it it again and this project is fun!

�You're quite right, it makes sense to wait for info on the casing width; there may be some help though, in knowing whether or not the tyre sizes were the same front and rear - if so, the rear wheel rim will be just a little bit wider than the width of two single tyres with a narrow gap between them. The width that comes to, plus the amount of space left to the chassis rail, will give an idea of the casing width.

At the risk of annoying by pointing out mistakes which may simply be typos (in this case because "i" and "o" are neighbours), I've highlighted "in" and "on" above just to say that these two should be swapped over between the two sentences. I realise that they both translate the same word in Spanish, so it's easy to confuse them, but if my pointing this out is annoying rather than helpful, please let me know.

I too enjoyed technical drawing at school - I remember the head of the tech department telling us that we should draw lines in two parts, starting at each end so as not to extend a line too far and mess up the corners. I opted for Graphical Communication (tech drawing plus a little graphic design) over art at school, but years later, now that I'm studying fashion, I occasionally wonder if choosing art might have set me on the right career path sooner.

d_fernetti · Hero

The whole rear axle assembly is somewhat shrouded in mistery... the most informative I mage I could find is this
Commer chassis?
which purportedly is a stripped Commer Car Chassis. Of course, how to know if it's the same type as in the ambulance? I have supposed that in any case, the structure is about the same for all chassis sizes of the era.

It does show that the front and rear wheels are about the same size (check the arc of circumference going over the chassis beam at front and at the rear), and how the crossbeams (pipes?) are placed in the chassis frame. Another hint of equal wheel diameter is that the chassis, being a simple affair made of straight C beams, is level to the ground, so... unless the leaf spring elliptics are different -probably not the case- the front and rear wheels are of the same diameter.

Note that the rear crossbeam is the connecting rod of the power gear.

It also shows that my GA drawing has either too small wheels or too high the chassis upper line.

Does any of our Landship forumites know where this this is rotting away? Does someone have more pictures of this "scene"?

PS (yes, Post Script!): Thanks for the corrections. I strive to polish my language skills. "On" and "In" (and "at" I must add) are one of those things that get easily overlooked and a frequent pebble in the shoe for us, non-english speakers.

Great War Truck · Brigadier

Do these help:

d_fernetti · Hero

Aaaarghhhh!

TinCanTadpole · Legend

d_fernetti wrote:
Note that the rear crossbeam is the connecting rod of the power gear.
It also shows that my GA drawing has either too small wheels or too high the chassis upper line.

�Which crossbeam do you mean? The only one I see that is anything to do with "power gear" is the axle.

Having looked back to the first page of the thread, the photos there suggest to me that your wheel diameter/chassis height is fine - the top of the wheel is more or less level with the top of the chassis rail.

GWT - "Non-runner, requires TLC..."� wink

Those pics look handy - I don't think the detail on that chassis is as bad as one fears when looking at murky period photos.

d_fernetti · Hero

Ah, how to name it! I wrote "crossbeam" but maybe that's not the exact word. There's a cylindrical structure member across the chassis frame between the casings of the gear drive, just in front of the rear axle leaf spring shackle (hope to be writing the technical terms right). The axle -as I understand- it's just what goes between wheels.
The new rusty chassis pictures show how the "fences" under the chasiss rails are attached to it (it was one of the things I missed before). But these lack the same cross-members of round section that my chassis photo showed.
Oh well.
D.

Great War Truck · Brigadier

To make sure I dont lose anything in translation Aaaarghhhh" represents your frustration that the chassis is different again?

The explanation for that is also why there are so few complete lorries and so many surviving chassis in this country. When the trucks were all worn out they were converted into trailers usually by farmers. Anything they could remove for scrap to sell they did and this would also get the weight down. Sometimes the chassis are even shortened. The latest photos look like the chassis has had its cross members removed. It would flex terribly without them, but thats not much of a problem if the drive train has also been removed.

TinCanTadpole · Legend

Indeed not: that last truck - in fact, both of the last two - are now powered Flintstones-style

D - I wondered if that was the part you meant, but I can't see it in that pic; I think the size and angle of the photo has made it look as if that tubular cross-member was the part you mean, but it's not.
The cross-member you can see is nothing more than a cross-member, to brace the chassis; the "power gear" part (I'm struggling myself for technical terms!) is underslung�- it hangs just underneath the chassis rails, from cast brackets that can be seen clearly in GWT's first pic, next to the shackle for the semi-elliptic spring. You can see the half-round recess that what I'm going to call the "half-shaft tubes" fit into.�

This, I expect, will be part of the transmission in the middle of the truck. After the drive comes backwards from the engine, there should be a gearbox - probably combined with a differential to form a "transaxle" (transmission/axle�unit); the differential will sit between the drive sprockets, with half-shafts (short drive axles) leading out on either side to the drive sprockets, which then drive the back axle via the chains.

In other words, that cross-member can't be the sprocket axle tube, because there needs to be a differential in the middle of it.

Great War Truck · Brigadier

You are quite right. From either side of the gearbox come "Jack shafts" which drive the chains which conect with sprockets on each wheel. Therfore the back axle has no other purpose but holding the wheels straight.

TinCanTadpole · Legend

See the plans here

Most seem to show a drop arm on the outside of the chassis rail (able to swing forwards and backwards) with a rod connecting it to the steering arm of the wheel hub, which I think is angled backwards and inwards. A tie rod crosses from the steering arm to one on the other wheel carrier.

Edit�- Ah! link not needed. Well, the bodies may be boxes, but in the case of the Mack, that bonnet/hood is quite a shapely box - certainly compared to most WW1 trucks, which are very 'boxy'.�

Those drop-arm steering gears have reminded me that sports cars used to have steering like that too, such as Bugattis of the 20s and 30s. There's a company in Argentina that makes quality replicas of these Bugattis; it's called Pur Sang, which I think is French for 'pure blood'. Only those with deep pockets need apply...

-- Edited by TinCanTadpole on Tuesday 19th of June 2012 02:25:27 AM

d_fernetti · Hero

Found the steering linkage!
Commer_Car_%28EC_634%29,_2006_HCVS_London_to_Brighton_run.jpg

There's a hint of the tie rod right behind the EC 634 plate. Also, first time I get a glipmse of it.
Now, how this thing goes up to the steering column?
BTW this picture (that I just found) shows the front wheel camber. Very subtle, but evident comparing the front and rear wheels...
off to the drawing board, once again!

-- Edited by d_fernetti on Tuesday 19th of June 2012 03:20:32 AM

d_fernetti · Hero

Been studying these pictures for a few days, and correcting my drawings accordingly. Have a question: does anyone knows how would the front axle connect to the steering column? Much like a Mack Bulldog, perhaps? It might be fairly visible under the chassis, but never stumbled upon this detail.
Another question: would the front wheels be "tilted inwards" (sorry, maybe there's a proper name for this feature) to make turning more easier and going in a straigh direction more stable? If so, how many degrees of inward tilt?

TinCanTadpole · Legend

Yes, the front wheels would be "cambered" - tilted. The camber would be "positive camber", in other words tilted out at the top. Vehicles nowadays use negative camber - the top of the wheel leans inwards, improving stability. On old vehicles stability at speed was not such an issue, it was more important to make steering easier, so they tilted the top of the wheel outwards so that the centre-line of the wheel (as seen from the front) touches the ground at the same spot that the axis (pivot line) of the kingpin (the hinge/pivot that the wheel steers on) does.

Normally a vehicle will have an arm cast into the wheel carrier and a tie rod will be used to connect this arm to the steering box. It's probably similar to the Mack and other trucks of the era - the original Landships site - landships.freeservers.com - has a section on plans by Ken Musgrave, which includes various trucks; some of those plans may be detailed enough to show steering gear.

d_fernetti · Hero

Thanks TinCan!
Been looking to Mr. Musgrave's drawings (and several dozens of partial snapshots) to see how some things are, but some always escape scrutiny.
So far, from a modelling point of view, it's been easier to draw in separate "layers" the details that will eventually be gathered (perhaps digitally) on a single 3-view General Drawing. Wheel spoke shapes interfere with mudguard supports, the gear drive cover interferes with the brake rods, and so on. One thing that attracts me of these old designs is the layered arrangement of the chassis, that makes them far more interesting to the eye than modern, streamlined vehicle designs.
I recall that building the MAck and the Ford T chassis was the fun part. The bodies... well, they are just bleedin' boxes!

d_fernetti · Hero

Indeed.... Pur Sang is in another province, a few hundreds of Km away from here. Seen their Avro 504 replica once...

d_fernetti · Hero

Been perusing also at http://hmvf.co.uk/forumvb/showthread.php?429-WW1-Dennis-truck-find/page108
Do you think that a Dennis lorry would have a similar steering mechanism?

TinCanTadpole · Legend

d_fernetti wrote:
Seen their Avro 504 replica once...

�Of course! I'd forgotten that they do planes as well.

I'm not sure if the tie rod between the wheels is visible in that pic, but certainly the steering arm attached to the right wheel carrier (not sure of the right term for that) can be seen above the beam axle and the semi-elliptic spring.�

If you look at Ken Musgrave's Mack plans�again, you'll see the important parts for how this connects to the steering column. The tie rod for the mack seems to be in front of the axle and is visible in the 'front end elevation' - the front view. The steering arm can be seen on the left side of the truck (right side of the front view) running inwards horizontally from the wheel carrier, above the end of the beam axle. You'll see a vertical rod connected to the end of the steering arm, going upwards, with a connection at the top next to the chassis.

This rod is the drop arm, which is on the end of a short shaft that sticks through the side of the chassis; when the shaft turns, the drop arm swings either backwards or forwards (according to which way you are steering), either pulling or pushing a horizontal connecting rod (running lengthwise) to move the free end of the steering arm, thus turning the wheel.

The shaft I have mentioned (sticking through the chassis side) is the output shaft from the steering box, which will be tucked away out of view on many vehicles. It is most likely that the Commer has this arrangement, except that the steering parts are on the other side from the Mack, because the Commer is right-hand-drive.

Hopefully that is a clear enough description - if not, I can draw a sketch.

-- Edited by TinCanTadpole on Tuesday 19th of June 2012 07:06:34 PM

d_fernetti · Hero

A sketch? And depreve me from the fun of doing it myself, and correcting it endlessly? Mais non, monsieur!

Runflat · Lieutenant-Colonel

As a follow-up to the earlier link to the Packard horse-lorry (you can't really call it a horse-box!) a similar idea was deployed in the British maneouvres of 1925. This example ("the Flying Scotsman") is on an Albion chassis - the hinged tailboard is raised and lowered by a hand winch through cables passing over pulleys on the top of of a pair of uprights. Two steel supports are placed in position to take the weight at the hinge line.

d_fernetti · Hero

Here's something interesting I found in Ebay

Seems like someone is auctioning a Commer Manual of a bus chassis that looks suspiciously like the lorry on which the horse ambulance is mounted on... too bad the scans are very little!!!!!

�

D.

-- Edited by d_fernetti on Tuesday 26th of June 2012 02:20:45 AM