LHD vs RHD hogs head design

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Tmodelt
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LHD vs RHD hogs head design

Post by Tmodelt » Sun Dec 22, 2019 12:35 pm

Help! I am dumber than a post and need some smart people to instruct me on the reason/reasons for the design differences between a 26/27 LHD and 26/27 RHD. hogshead

The difference where I get confused is, Why is there only 1 external adjustment bolt (clutch) on the LHD and 2 external adjustment bolts (reverse and brake) on the RHD?

Is there a mechanical reason? ie. Did the reverse and brake bands reveal that they required more adjustment during service?

I just would like to know if/when someone asks me. Thanks in advance.

Kim R. Wynn (RHD newbie)


Les Schubert
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Re: LHD vs RHD hogs head design

Post by Les Schubert » Sun Dec 22, 2019 6:59 pm

I want you to think about how the torque loads are applied to the bands. You don’t want the torque to be pushing back against the pedal pressure


tdump
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Re: LHD vs RHD hogs head design

Post by tdump » Sun Dec 22, 2019 8:57 pm

I think what Les is saying is that the engine would have to counter rotate not to have any issues with the bands.Correct?
All I know is,I would LOVE to have the stuff to make a right hand drive T.
If you can't help em, don't hinder em'


Les Schubert
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Re: LHD vs RHD hogs head design

Post by Les Schubert » Sun Dec 22, 2019 9:52 pm

Mack
I built my ‘13 starting with a hogshead and a Canadian 13 block. Converted the bottom of the steering column and the brake lever. The body gets 2 front doors. It took a couple of years effort


Topic author
Tmodelt
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Re: LHD vs RHD hogs head design

Post by Tmodelt » Sun Dec 22, 2019 10:03 pm

Les, so the adjustment studs hold against the rotational forces? And since the clutch stays in high gear (band released) most of the time it no longer needs this counter force?

KRW


Topic author
Tmodelt
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Re: LHD vs RHD hogs head design

Post by Tmodelt » Sun Dec 22, 2019 10:08 pm

Mack, I am building a boattailed speedster using a glass roadster tub and one piece removable hardtop. I will be installing my own wood kit and cut both doors for suicide hinges and latches. I have the engineering worked out already just not on paper. I was a racecar fabricator / machinist in a past life.

KRW


Kerry
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Re: LHD vs RHD hogs head design

Post by Kerry » Mon Dec 23, 2019 1:31 am

Can't see torque loads making any difference, drums turn the same in LHD and RHD, but the peddle cams are on either side, left side for the LHD and right side for the RHD, and also the brake drum turns both ways for band action, forward and reverse.


Les Schubert
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Re: LHD vs RHD hogs head design

Post by Les Schubert » Mon Dec 23, 2019 11:11 am

Kerry
Your assumption is incorrect. I will stay with my original explanation


nsbrassnut
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Re: LHD vs RHD hogs head design

Post by nsbrassnut » Mon Dec 23, 2019 2:33 pm

Hi All

Here are some pictures of RHD hogs head assemblies. These ones are the earlier aluminum version for 14-15, but the basics are similar for all of them.

When you look close at the RHD differences, it looks like RHD design was an afterthought. The RHD parts are jammed in and prone to problems. The clutch pedal will hit the hogs head if bent even a bit to the left and the brake pedal will hit the exhaust pipe if the pipe is a standard shape and not modified for extra clearance. The shape and bends on the pedals are more awkward for RHD and are easily bent out of shape when heavy feet are used.

As already mentioned, the direction of the rotation of the transmission drums is the same in both LHD and RHD, the transmission gears, drums and other guts are the same for both. The direction of the reaction torque from contacting the bands is the same for both. So in the RHD, pedals all move in the SAME direction (left or right) the LHD ones and the reaction torque is applied to the opposing part. Look close at the pedal shaft cams and you can see how for example the reverse pedal shaft moves to the right in both cases. For LHD right is into the hogs head, for RHD right is out of the hogs head.The results in same side of the band being "pushed in" in both cases. For LHD right is into the hogs head, for RHD right is out of the hogs head.The same left side of the reverse band is "pushed in" in both cases.

Drive Safe
Jeff
Nova Scotia
Attachments
15 Ford RHD trans inside.jpg
Ford RHD alum hogs head 3.jpg
Ford RHD alum hogs head 2.jpg
Ford RHD alum hogs head.jpg
Ford LHD Hogs Head.jpg


nsbrassnut
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Re: LHD vs RHD hogs head design

Post by nsbrassnut » Mon Dec 23, 2019 2:34 pm

Hi All

Ran out of pictures space. Here is the '15 RHD pedal set up.

Drive Safe
Jeff
Nova Scotia
Attachments
15 Ford RHD Pedals.jpg


Kerry
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Re: LHD vs RHD hogs head design

Post by Kerry » Mon Dec 23, 2019 3:28 pm

Les, l don,t disagree that the push and pull aren,t the same on both set ups but pedal pressure can,t be avoided on the brake when the drum turns both ways.


Les Schubert
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Re: LHD vs RHD hogs head design

Post by Les Schubert » Mon Dec 23, 2019 5:02 pm

Kerry please study Jeff’s pictures. Yes the brake is used in reverse, but far less than forwards


Luxford
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Re: LHD vs RHD hogs head design

Post by Luxford » Mon Dec 23, 2019 5:52 pm

I have to agree with Kerry on this and somehow Jeff has got it mixed up.

In both LHD & RHD the pedal action is identical.
Therefore any forces applied to a band is identical in both cases

The reverse and brake pedal shafts move to the left in both LHD & RHD
the clutch pedal shafts move to the right.

The cam actuators on the hogshead for the pedals are the same whether LH or RH.

On the LHD the reverse and brake cams are bolted onto the outside(left side ) the clutch on the inside

The same cams are used on the RHD and they appear to be opposite but are bolted onto the hogshead (right side) exactly the same way.
which means the reverse and brake cams are inside the hogshead and the clutch is outside.

The pedals in both RH & LH move in the same direction Reverse and Brake to the left
Clutch to the right.

Obviously if things get out of "wack" problems can occur but on RHD the clutch when pushed in moves right away from the hogshead.
The brake pedal moves left away from the exhaust.
On RHD the exhaust pipe is different due to the pedals being there but Henry was thinking only for LHD initially.

I think RHD got the best result, it has both reverse and brake adjusters outside and only the clutch inside.
LHD is the exact opposite.

As that's the case then there is no difference in torque loads on the bands between the LHD & RHD


Alan Long
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Re: LHD vs RHD hogs head design

Post by Alan Long » Mon Dec 23, 2019 7:20 pm

A little bit of trivia for our Friends in the USA... we refer to your “Hogs Head” as “Pigs Head” in Australia.
The name of course has no influence in its operation except when we have issues working on them and
they get called “a Pig of of a thing” (or worse)
Merry Christmas Gents
Alan in Western Australia

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Mark Gregush
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Re: LHD vs RHD hogs head design

Post by Mark Gregush » Mon Dec 23, 2019 7:52 pm

One of my customers was putting a right-hand drive speedster together, I had some choice words and names for that hogs head that can't be printed here. :lol: (It was my first experience running a lathe too, the pedal shafts are not off the shelf here in the US)
I know the voices aren't real but damn they have some good ideas! :roll:

1921 Huckster
1925 Cut down pickup


nsbrassnut
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Re: LHD vs RHD hogs head design

Post by nsbrassnut » Mon Dec 23, 2019 9:47 pm

Hi All

Luxford, please look again at the picture of the pedals and a bit closer. Only the clutch shaft moves to the right on the RHD, both the reverse and the brake shafts move to the left when the pedal is pushed. I think its the same as the LHD.

The band ear that is "pushed" by the pedal action and the ear that is "anchored" against the solid casting (or adjustable screw) is the same for both RHD and LHD. The movement action on the band is the same in both cases. However the shaft moving in or out of the hogs head is what is reversed.

On the RHD when the clutch pedal is pushed down, the shaft moves out of the hogs head, ie. moves right. The same way as the LHD which moves into the hogs head when pushed and still moves right.

Here are pictures of the two different clutch cams. The rusty one in a cast head is a LHD, the one in the aluminum head is a RHD. Take a close look.

And yes, the pedal shafts are different lengths for the RHD as are the pin holes.

Drive Safe
Jeff
Nova Scotia
Attachments
LHD Clutch Cam.jpg
Ford RHD clutch cam.jpg


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Re: LHD vs RHD hogs head design

Post by Luxford » Mon Dec 23, 2019 10:57 pm

Jeff,
I agree, that"s what I have written,
but in your first post (at 3:33am) you stated the reverse post moves to the "right"

( Look close at the pedal shaft cams and you can see how for example the reverse pedal shaft moves to the right in both cases.)

Here is a simple sketch of both. Moving in or out of the hogshead does not matter both types clamp the drums the same.

Another good feature of the RHD is the pedals don't interfere with the starter bendix or its cover.

In Australia we have also LHD hogsheads made into RHD in the 1920's, something Canadian and American's would not have seen.
Attachments
PEDAL ACTION.jpg


nsbrassnut
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Re: LHD vs RHD hogs head design

Post by nsbrassnut » Tue Dec 24, 2019 9:36 am

Hi all

Luxford please accept my apologies.

Your sketch clearly shows what I was trying to describe about how the shafts move.

I checked the pictures several times and still managed to mix one up in my earlier note.


Happy Holidays
Jeff
Nova Scotia

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