Caterpillar D6A

[Jakko Westerbeke]

At the invitation of its new owner, I went to look at a D6A today:



This arrived last Monday from the UK, where it had sat outside, apparently in the woods, for a good amount of time. It still has fairly substantial pieces of the original armour plate (22 mm thick, incidentally — I don’t think I’ve read the actual thickness anywhere) as well as the fuel and hydraulics tanks, seat, instrument panel etc. of the armoured version rather than the normal, unarmoured D6. The tracks are also the original military ones, which apparently differ from the civilian type in both width (50 cm vs. 44, IIRC) and material (high-nickel steel vs. lower-quality). The remains of original military paint are still there too, under the yellow.

The ID plate is still legible:



Chassis number 1T3045.

And it came with these bits too:



The original winch and dozer blade, though the latter appears to have been modified to be a snow plough and the arm is incomplete, partially rusted through and with bits sheared off. But it should be repairable, by the looks of it.

[Hanno Spoelstra]

Wow, what a find! Is this part of the Cat stable of Willem de Braal?


PS: for good measure I attached a picture of D6A - 1T3037 35839-1136 LCT = Det 59 M E Sec - Dozer Exxx221- (censored) 'WINNIE FAY.'- p012929 as identified by Michel Saberly:


Source: https://flic.kr/p/zRPqD6

[Jakko Westerbeke]

Willem is the one who posted about it here, but the dozers are owned by the De Braal family, yes. They’ve got three D6s now

The intention is to put the armoured cab back onto this one, probably by fabricating a complete replacement and fitting it instead of the cut-down one that’s still on the vehicle now (the real one, of course, will be saved as well).

[Alex van de Wetering]

I agree....what a find......and not 1, but 3 CATs, sounds like the project has got very serious!
Thanks for sharing the pictures Jakko. I hope Willem will drop by to tell us more about the project and his exiting finds!

The intention is to put the armoured cab back onto this one, probably by fabricating a complete replacement and fitting it instead of the cut-down one that’s still on the vehicle now (the real one, of course, will be saved as well).

Personally I would try to complete this one by welding in the missing pieces, rather than making a complete repro set of armour......it would be a shame not to use as much of the original as possible and it's certainly no disgrace if one can see where new sections were welded in.....it would tell an interesting part of it's history!

[John P]

What kind of shape is the undercarriage and track frames in?.The folks with the ACMOC might also be of some help with your machine.Very nice find

www.acmoc.org

[Jakko Westerbeke]

Originally Posted by Alex van de Wetering

sounds like the project has got very serious!

You don’t know the next part yet … “We’re trying to get a permit to dig a big hole in your beach”

Originally Posted by Alex van de Wetering

Personally I would try to complete this one by welding in the missing pieces, rather than making a complete repro set of armour......it would be a shame not to use as much of the original as possible and it's certainly no disgrace if one can see where new sections were welded in.....it would tell an interesting part of it's history!

I had assumed they would weld plates into the openings, but when I mentioned this, I was told that apparently their plan is to fabricate a new cab completely. “You’ll never get welded-in plates to look quite right” I think was the reason. My POV was also that if you close the holes, you’ll have the original armour on it as much as possible.

Originally Posted by John P

What kind of shape is the undercarriage and track frames in?.

I’m not a real vehicle restoration expert (the 1:35 scale versions are more my thing) but they looked OK, though some of the sheet metal was rusted. The track, though, still works fine — the links moved under my weight as I stood on top of it to get into the cab.



As said, though, they have two other D6s, and plan to use parts from at least one of them.

[maple_leaf_eh]

There's a Youtube channel for everyone and everything. If I can find it again, there is one about a fellow who found a 1950s Caterpillar dozer and got it running (salvage workshop). Everything on it is just really big and really heavy. He needed to replace an awful lot of hoses, gaskets, and seals in addition to unbuilding previous owner repairs. In the end it was as satisfying to see his success as it was for him to get there. One thing to keep in mind is the 24-Hour Overnight Delivery 1940s Caterpillar dozer parts store has been shut since the start of the pandemic, and getting the pieces you need will be quite hard.

[Jakko Westerbeke]

I’m fairly confident they’ll be able to get it running — the chap pointing at the engine in the photo there is the one who bought the dozer

[Matthew P]

Awesome project.

Caterpillar is very proud of their history. The dealer in my area painted up the engine that's on display at the Smithsonian. If the local CAT dealer isn't all over helping out, than go to Corporate. I'm in a class at Caterpillar this week for work and am quite impressed with them as an outfit, overall not just as an engine and equipment maker.

Matt

[John P]

Any update?

[Jakko Westerbeke]

I haven’t been back, but earlier this year I asked about it, and by this photo he sent me, they’ve started rebuilding the armour:



And are doing it by welding pieces into the existing plates, rather than building a new cab from scratch as they originally intended to do.

[tankbarrell]

I thought the 1T serials were all D7s?

[Jakko Westerbeke]

Originally Posted by tankbarrell

I thought the 1T serials were all D7s?

No, 1T is the prefix for all the armoured bulldozers Caterpillar built for the British, both D6(Armored) and D7(Armored).¹ The D6s were 1T3001–1T3045² and the D7s were 1T1001–1T1138.


¹ Which, BTW, appear to be Caterpillar’s actual designations, rather than D6A and D7A that everyone uses nowadays.
² But there is a photo of one marked 1T3060 as well, which has yet to be explained AFAIK.

[tankbarrell]

Thanks for that Jakko! I knew the 1T serials don't appear in normal Caterpillar productions lists but had just thought they were all D7s. Good to know the facts.

[David Herbert]

I am sure that I have seen standard un-armoured D7s with 1T numbers but I didn't record the actual number and of course they could have been rebuilt from armoured ones. Post war there were also 3T and 4T un-armoured D7s. I wonder what the 2Ts were if that designation was used?

David

[tankbarrell]

2T's were standard D4. 2, 3 and 4T serials all appear in Caterpillar production lists but 1T's do not.

[Dave Newcomb]

There is an extensive Cat museum in the Powerland complex in Brooks, Oregon Those folks may be a help. Dave [in Oregon USA]

[Alex van de Wetering]

Originally Posted by Jakko Westerbeke

I haven’t been back, but earlier this year I asked about it, and by this photo he sent me, they’ve started rebuilding the

And are doing it by welding pieces into the existing plates, rather than building a new cab from scratch as they originally intended to do.

That's awesome! I am happy they choose to take this route and restore the original armour in stead of making something new!

[Jakko Westerbeke]

Originally Posted by tankbarrell

I knew the 1T serials don't appear in normal Caterpillar productions lists

They do for the D6(Armored):


(previously posted here)

I haven’t seen a list for the D7-series, but I would suspect they appear there too?

Originally Posted by David Herbert

I am sure that I have seen standard un-armoured D7s with 1T numbers but I didn't record the actual number and of course they could have been rebuilt from armoured ones.

According to this page, only the armoured ones had 1T prefixes.

Originally Posted by David Herbert

Post war there were also 3T and 4T un-armoured D7s.

Actually from 1944, according to that same site. I get the impression from that that 3T was the next prefix used for the D7 after the 3M series reached 9999 (the 1T D7s are basically 3M-series tractors with armoured cab etc.) while 4T is from another factory.

[Tim Bell]

2C is for the Medium M4 tank transmission units.

[tankbarrell]

But is that book a Caterpillar publication? I have two different lists compiled from Caterpillar records (apparently) and none of the 1T serials are mentioned.

[Jakko Westerbeke]

Originally Posted by tankbarrell

But is that book a Caterpillar publication?

I don’t know for sure, but I suspect it is. I got the photo from one of the guys restoring this bulldozer, and they’ve got pretty short lines to Caterpillar. They also got copies of factory drawings of the overall layout, for example:

[David Herbert]

Those drawings are marked Caterpillar Tractor Co. I had thought that the armour was designed, made and fitted in the UK, possibly by Jack Olding Ltd. I can't see a reason for Cat to give a separate code to armoured tractors and only add 'SP' to other variants like pipe cranes which are just as different to base machines. There were lots of standard 7M D7s used by the military so it isn't because they were military contract.

David

[Jakko Westerbeke]

Originally Posted by David Herbert

Those drawings are marked Caterpillar Tractor Co. I had thought that the armour was designed, made and fitted in the UK, possibly by Jack Olding Ltd.

That is a common misunderstanding. Jack Olding was the UK importer for Caterpillar, and fitted some D8s with waterproof hulls to use as BARVs, which is where I suspect the confusion comes from. However, as I understand it, the D6(Armored) and D7(Armored) were entirely built by Caterpillar itself in the USA. Caterpillar having made drawings of the armour is a strong indicator, IMHO. (Note that there are some mistakes in the drawings, mainly the rear view: the hydraulic cylinders are too far apart, most likely because someone overlooked that the bonnet is narrower than the rear plate.)

[Jakko Westerbeke]

I just got some new photos from Christiaan de Braal, who said it was OK to post them here:



Not sure why they wrote 1T3038 on the front when it looks like it’s actually 1T3045, though. I suspect it’s because they’ll be recreating the armour for that one too, since 1T3045 still had some of the original armour around the engine.

[Ed Storey]

Fantastic work and exciting to see!

[John P]

Fantastic work

[Jakko Westerbeke]

I’ll be going back tomorrow to take another look, and will post more pictures of the current state then.

[John P]

Originally Posted by Jakko Westerbeke

I’ll be going back tomorrow to take another look, and will post more pictures of the current state then.

Did you get any help from the ACMOC in the states?.Looking forward to seeing the pictures of your progress.I cannot wait to see this one compleated

[Jakko Westerbeke]

It’s not mine — I build these kinds of things in 1:35 scale, not 1:1 I just know the owners of the dozer pictured, who sometimes e-mail me to say, “Come over to take another look!”