MLU FORUM  

Go Back   MLU FORUM > MILITARY VEHICLES > The Softskin Forum

Notices

Reply
 
Thread Tools Display Modes
  #1  
Old 22-01-14, 19:22
Mike Cecil Mike Cecil is offline
Registered User
 
Join Date: Jun 2006
Location: Cody, Wyoming, USA
Posts: 2,372
Default 'Kits, Recovery'

I assume a Dawn No.2 simply means a two ton capacity winch, which is what the 'Kit's Recovery' specified, along with 120 feet of 3/8 inch wire rope. (So is a Dawn No.5 a 5 ton capacity winch with, presumably, a heavier/thicker rope?)

The winch assembly and fitting was described in MGO Equipment Memorandum 13 of Sept 1944 - which I assume is what Ian is using as his main reference. The kits were manufactured by Ford Motor Company (there is more to the kit than the basic Dawn winch), with 230 kits ordered under CD-E8745.

Problems were encountered in the supply of the correct diameter wire rope, which slowed delivery until a variation to design was authorized.

Have never been able to find anything definitive on the number built, but judging from photo images, I'd guess not very many made it onto the front of jeeps.


Mike C
Reply With Quote
  #2  
Old 25-01-14, 10:46
Tony Wheeler's Avatar
Tony Wheeler Tony Wheeler is offline
Registered User
 
Join Date: May 2012
Location: Yarra Junction VIC
Posts: 953
Default

Quote:
Originally Posted by Mike Cecil View Post
So is a Dawn No.5 a 5 ton capacity winch with, presumably, a heavier/thicker rope?
The same thought occurred to me the other day Mike when I learned it was a No.5 but I couldn't find any info on the net. However I believe it's just a Dawn ID number rather than a capacity rating, and there's certainly no such claim on the winch itself. It looks pretty much the same as the one on the jeep so I don't see how it could be 2 1/2 times stronger. Also if the front of that Cab 12 weighs in the vicinity of 2 tons as I imagine it would, then based on the force required on the long Dawn crank handle I would consider that to be a reasonable rating, bearing in mind they're usually on the conservative side. I'm sure it could lift more, especially with less cable on the drum, but even if it could lift 5 tons, which I'm inclined to doubt, I would definitely rule it out as a rating for all practical purposes. I'm pretty sure you're not supposed to hang off the end of the handle with your feet kicking wildly in the air trying to turn it!

TONY7516 - Copy.jpg

TONY6179 - Copy - Copy.jpg
__________________
One of the original Australian CMP hunters.
Reply With Quote
  #3  
Old 25-01-14, 11:15
Lynn Eades Lynn Eades is offline
Bluebell
 
Join Date: May 2003
Location: Tauranga, New Zealand
Posts: 5,541
Default

So the pioneering spirit is dead then
__________________
Bluebell

Carrier Armoured O.P. No1 Mk3 W. T84991
Carrier Bren No2.Mk.I. NewZealand Railways. NZR.6.
Dodge WC55. 37mm Gun Motor Carriage M6
Jeep Mb #135668
So many questions....
Reply With Quote
  #4  
Old 26-01-14, 11:54
Brett Nicholls Brett Nicholls is offline
Registered User
 
Join Date: Jul 2007
Location: Sydney, Australia
Posts: 119
Default Dawn Winch

Hi Guy's,
Another AWM picture and ......again Dawn winch mounted on a Ford Jeep! Obviously Fords were not quite as good as the Willys and needed the extra help

Oh what can of worms I think I just opened

On a serious note - I some how think the installation was easier on the Ford's due to the front cross member shape but I have no proof - it's just a hunch. Note also the front grille intact vertical bars.

Regards,
Brett.
Attached Images
File Type: jpg 108877.jpg (52.6 KB, 18 views)
__________________
Brett Nicholls

Last edited by Brett Nicholls; 26-01-14 at 11:55. Reason: additional info
Reply With Quote
  #5  
Old 26-01-14, 12:00
Richard Farrant's Avatar
Richard Farrant Richard Farrant is offline
Registered User
 
Join Date: Feb 2003
Location: Kent, England
Posts: 3,641
Default

Quote:
Originally Posted by Brett Nicholls View Post
Hi Guy's,
Another AWM picture and ......again Dawn winch mounted on a Ford Jeep! .
I can see now how the folding handle was stowed.
__________________
Richard

1943 Bedford QLD lorry - 1941 BSA WM20 m/cycle - 1943 Daimler Scout Car Mk2
Member of MVT, IMPS, MVG of NSW, KVE and AMVCS
KVE President & KVE News Editor
Reply With Quote
  #6  
Old 26-01-14, 12:01
Lynn Eades Lynn Eades is offline
Bluebell
 
Join Date: May 2003
Location: Tauranga, New Zealand
Posts: 5,541
Default

Brett, Re the "Can of Worms"
Maybe the Ford chassis was robust enough to handle the load?

.......and it is a Ford because????
__________________
Bluebell

Carrier Armoured O.P. No1 Mk3 W. T84991
Carrier Bren No2.Mk.I. NewZealand Railways. NZR.6.
Dodge WC55. 37mm Gun Motor Carriage M6
Jeep Mb #135668
So many questions....
Reply With Quote
  #7  
Old 26-01-14, 18:49
Tony Smith's Avatar
Tony Smith Tony Smith is offline
No1, Mk 2** (I'm back!)
 
Join Date: Feb 2003
Location: Lithgow, NSW, Australia
Posts: 5,042
Default

More pics in THIS THREAD.

I'm trying to find to old "For sale" thread when I sold my Dawn Winch, and I think it was either Ian or Brett who ended up buying it. Was lots of pics in that listing.
__________________
You can help Keep Mapleleafup Up! See Here how you can help, and why you should!
Reply With Quote
  #8  
Old 26-01-14, 19:02
Tony Wheeler's Avatar
Tony Wheeler Tony Wheeler is offline
Registered User
 
Join Date: May 2012
Location: Yarra Junction VIC
Posts: 953
Default

Quote:
Originally Posted by Tony Wheeler View Post
I'm pretty sure you're not supposed to hang off the end of the handle with your feet kicking wildly in the air trying to turn it!
Upon reflection my own winch cannot be considered indicative, because the cable drags on the crossbar due to poor installation. This would greatly increase the handle force required, particularly with heavier loads.

TONY7518 - Copy.jpg


For a proper installation we can calculate the handle force required from the gearing (24.5:1 reduction in low ratio) and the mechanical advantage provided by the crank handle radius (485mm for the Dawn handle) relative to the cable winding radius (approx 50 - 150mm depending on how much cable is wound on the drum). For a 2 ton lift this works out to between 19 and 57 lbs. A standard two gallon plastic bucket of water weighs 20 lbs, which means that for the first layer of cable on the drum you could lift 2 tons easily with only one hand, using only the force required to lift a bucket of water. Even with the drum fully wound you could comfortably exert 3 times that force using two hands. If you really put your back into it you could probably manage 100 lbs, which would lift 3.5 tons with the cable drum full, or 10 tons with the cable drum empty. For someone of my weight (approx 85 kg) you would only need to hang off the handle if you were lifting 7 tons with the cable drum full, or 20 tons if it were empty. Based on these calculations you could reasonably rate this winch at 3 tons, requiring 57 lbs handle force, ie. 3 buckets of water, with the cable drum half-full.

We can perform a similar calculation for the Dawn No. 2 winch on the jeep. While it appears to be identical to my Dawn No.5 winch, closer inspection reveals it to be considerably smaller, the only common part being the pinion gear. As a double reduction winch the relative size of the larger gears indicates a ratio of around 16:1 on this unit, which being approx 2/3rds of the No.5 ratio would lead to a rating of 2 tons instead of 3 tons.

Irrespective of any nominal rating it's the wrong choice for the jeep application in my view, being far too low geared.

dawn-1 - Copy.jpg

TONY7517 - Copy.jpg
__________________
One of the original Australian CMP hunters.
Reply With Quote
  #9  
Old 26-01-14, 19:35
Tony Wheeler's Avatar
Tony Wheeler Tony Wheeler is offline
Registered User
 
Join Date: May 2012
Location: Yarra Junction VIC
Posts: 953
Default

Quote:
Originally Posted by Tony Wheeler View Post
Irrespective of any nominal rating it's the wrong choice for the jeep application in my view, being far too low geared.

Having just seen this pic of the Dawn No.2 winch drum bare of cable I may need to reconsider, as the inner diameter appears to be considerably larger than the No.5 drum on which my calculations are based. This would improve the situation although I suspect it was still geared overly low for the required purpose.

jeep0041.jpg
__________________
One of the original Australian CMP hunters.
Reply With Quote
  #10  
Old 27-01-14, 01:52
David Dunlop David Dunlop is offline
Registered User
 
Join Date: Feb 2006
Location: Winnipeg, MB, Canada
Posts: 3,599
Default

Not to detract from this thread, Tony, but what is the purpose of the metal boxes covering the front bumper mounting points? Never seen that setup before. Part of the winch kit perhaps?


David

Last edited by David Dunlop; 27-01-14 at 03:42.
Reply With Quote
  #11  
Old 27-01-14, 02:28
Lynn Eades Lynn Eades is offline
Bluebell
 
Join Date: May 2003
Location: Tauranga, New Zealand
Posts: 5,541
Default

David, I would suggest a bumper extention as the winch mount sticks out forward of the bumper.
Interestingly this is a slat grill (first 10,000 and all of course were on Willys Chassis)
That the guard is already damaged and that there is a sheet of mesh in front of the radiator.
There is a hook on the front bumper, that I would guess is for a 2:1 pull.
(rope eye back onto the Jeep?)
I see also that the park light has been moved and that the bonnet is unbolted and sitting forward.
__________________
Bluebell

Carrier Armoured O.P. No1 Mk3 W. T84991
Carrier Bren No2.Mk.I. NewZealand Railways. NZR.6.
Dodge WC55. 37mm Gun Motor Carriage M6
Jeep Mb #135668
So many questions....
Reply With Quote
  #12  
Old 27-01-14, 03:02
Mike Cecil Mike Cecil is offline
Registered User
 
Join Date: Jun 2006
Location: Cody, Wyoming, USA
Posts: 2,372
Default

This is an image of the early trials/test mounting. It was not how the design ended up. The extensions were indeed part of the early winch kit development, and because the test mounting protruded forward of the bumper.

The final mounting sat further back, and had a slat cut from the grill to accommodate this, as is visible in the early image posted on the thread, showing a jeep of the 24 Infantry Brigade HQ, 9th Infantry Division, with what looks like a Japanese officer in the back: possibly taking the surrender in British Borneo? Nice image.

Mike C

Last edited by Mike Cecil; 27-01-14 at 03:16.
Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Photos needed servicepub (RIP) WW2 Military History & Equipment 74 11-01-20 22:19
Photos needed David Dunlop The Softskin Forum 4 17-01-10 23:39
17-pdr photos needed servicepub (RIP) The Gun Park 2 01-11-09 02:20
1/4 ton WW2 Trailer Photos Needed pzrwest The Softskin Forum 2 29-06-09 12:59
original photos needed cliff The Softskin Forum 0 19-01-07 23:34


All times are GMT +2. The time now is 04:25.


Powered by vBulletin® Version 3.8.4
Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
Copyright © Maple Leaf Up, 2003-2016