Monday, June 23, 2014

TBs TechReview 34 – 42028, Bulldozer

 Set reference: 42028                                                                                                                                                               
Set name: Bulldozer
Theme: LEGO Technic
Release date: 2014.Aug

Number of parts: 617 (plus a few spares)

LEGO Designer: Kossi (Markus Kossman)

Model under review: Main model
Weight: 500g (1.10lbs) approx.
Approximate set dimensions:
Length - 28,0-29,1cm (11.0"-11.4")
Width - 16,5cm (6.30")
Height - 13,5cm (5.12")
Approximate box dimensions:
Length - 26,1cm (10.2")
Width - 28,1cm (11.0")
Height - 7,6cm (2.76")

Stickers: Yes
Numbered bags: No
Building instructions: 2 booklets for the main model (60 and 64 pages) + 2 booklets for B-model (84 and 32 pages)
B-model: Trench Digger

Recommended for ages: 9 - 16
Building difficulty level: Medium
Estimated building time: 1h 30m - 2h 30m

Price range: 40€
Price per part: 6,5 euro cents

Inventory (Bricklink): Link
Other user reviews (Brickset): Link

The 2H2014 LEGO Technic menu opens with a small/mid size bulldozer (42028). The last ones we got were small/mini sized versions in 2012 (9391 B-model) and 2009 (8259), and also the much larger mythical flagship 8275 which introduced the new LEGO Power Functions system in 2007.
It was about time, if we think we need to go back into 2005 (8419 B-model) or 1979 (856/877, the flagship at the time) to see another mid sized LEGO Technic bulldozer.

The newest LEGO Technic bulldozer has the particularity of have been designed by Kossi who also designed the 8275 Motorized Bulldozer above mentioned.

It is a nice pleasant model, but lets dive into the review material for the further details.

1. The package and contents

It arrives in a mid sized square and punch to open box style. Due to its relative large amount of parts for the box size, this comes with a generous filling and weight sensation of weight and.

The set is not motorized neither prepared for Power Functions upgrade. It includes the usual 2-in-1 characteristic from LEGO Technic sets, that allow to build one main and one alternate set (usually referred as B-model).

Some illustrations in the front and back sides of the box, make evidence of both models main functions.

Below a 3/4 box perspective as well as one unfolded detail view.

Inside we get four building instructions booklets (two for the main model and another two for the B-model) as well as one small sticker sheet for set decoration.

And of course the main content which are the parts required to build one of the two possible models.
These come in 5 separate non numbered bags, one of which just for the 62 track elements included.;
After sorting the bags over the table, here they are!

2. The new parts

The 2nd half of 2014 didn't gave us many new LEGO Technic elements, and sadly none of these are present in the 42028 box.

Although there are a couple of parts which are actually not that common due the few sets where they were release so far.
It is the case of:
  • The yellow 1x6 thin liftarm (32063), which was release in one set in 2000 and with 42024 Container Truck this year. There are hard to believe coincidences. Having this part needed in two sets this year after so many years is one of them.
  • The black 1x7 thin liftarm (32065), absent from Technic sets since 2007, and coincidence or not one of them back then was exactly the 8275 Motorized Bulldozer.
  • The new micro panels in black (11946, 11947), which were previously only released into another set from this year (42021 Snowmobile).
    Although a lost opportunity to realease them in yellow for the first time, as it would make more sense for the place where they're used in the model.
  • And finally my favorite axle/pin (11214) released just this year and already present into an abnormal number of sets for a new comer. One can say this was really in need for too long.

There is another fact worth mentioning although it was not introduced with this specific set or even this semester. I simply didn't realize about this small change for the 1H reviews and it was mentioned to me sometime afterwards.

The modification is barely noticed and consists of just a small modification into the mold of the Technic bush (3713). One of its sides always had a small recession, it happens this recession just got slightly deeper so it can be attached to a stud. Whether this is of any practical use, is something we will rest to see...

3. The parts assortment

Being it a tracked vehicle it will include of course some treads that might be useful if you're in need of them

Apart from that I'd say it is a very neutral set in terms of its assortment. A bit of several different parts including beams, liftarms, panels and connectors, but nothing very specific or less common to find.
If there is some exception to this I would choose to mention the differential.

Above there is a photo from this set's parts list included in the back of the first building instructions booklet.
Notice the 4563044 crank (part 33229) is listed twice in this list. It happens!...

4. Building experience

The build starts with the bottom of the chassis including the track rollers and idlers which in the present case is achieved with sprockets as if they were drive wheels.
It includes also the actuators that go into the front and back sides, which will allow to control respectively the Dozer front Blade and Ripper in the rear.
We can immediately notice the old style worm gears were used, but at least one of them could have been easily replaced by the new design introduced earlier this year. One likely reason for being not is that Technic designers always try to use the least number of different parts possible in a set. Hence having one worm gear type mandatory at one side and another optional at the other, designers might have chosen for the most simple solution for the production and have used two of the same kind.

The next steps consist of the 4-cilinder engine and part of the transmission which goes in place immediately afterwards.

The build-up proceeds with the final drive group. Notice that technically or better said more realistically this should be the only one using sprockets. But since this is not a self powered vehicle rather a toy, designers need to sacrifice the authenticity principle a bit and use sprockets also where the idlers should be so that the tracks are not so likely to jam, and get to roll easier as a kid pushes the Dozer in the floor.

The transmission goes bellow the final drive group with the solely purpose of increasing the shaft speed that connects to the engine, by the ratio of the bevel gars used (20/12). This could have been avoided (via direct transmission) or even further increased to a larger ratio, if the same relation was used on the other side. Somehow this might have been the speed-up factor intended by the designers to optimize the playability/speed of the engine as children push the Dozer.

There is also one differential block in the middle of the final drive group, with a purpose in mind. But we will return to this later in the Functions and Playability section.

Finally the rear actuator folds up to enclose the whole mechanisms and the chassis assumes its final form.

At this point we are almost at the end of the first booklet which finishes half way between the ripper linkage and ripper attachment. Picture below belong already to the second booklet when the rear ripper gets finally attached to the Dozer.

Some steps ahead we have added the air filter and some fairing to the top side, and it is time to add the tracks.

It follows with the driver's cabin structure and that's where I noticed a mistake in the building instructions which caught my attention while trying to figure out how to accomplish the respective building step.
At page 20, step 46 from the 2nd booklet there are two yellow 1x3 thin liftarms from the sub-assembly inserted in step 44, which suddenly disappear from their place at this page only.
It may cause some difficulties to the less experienced, as the sub-assembly introduced at step 46, attaches directly to the missing parts. Hopefully the Technic team will fix this minor problem in time for the next production batches.

Problem is depicted below, just for the case you get the same version as I did.

Having surpassed this, notice the sort of brick made small openable doors - one at each side of the cabin.

Before we go into the blade attachment details, it's time to build the front grill, which is nicely done with four 1x7 gear racks (87761).
Ha-ha! just noticed I've built them reversed... it's happening all the time!... Pay attention and don't build it like I did.

Now we have reached the point where we will build the front blade and the push frame that attaches to the crawler tractor.
The linkage it's a bit unconventional as it uses a rotating mechanism instead of proper hydraulic cylinders or their LEGO equivalent. But that's another topic we will also return to, later in this review.

The stickers applied to the blade side panels present some details in the decoration that pretend to copy natural scratches in the painting, resulting from the normal use of this type of machinery.
A nice detail that probably could have resulted even better if these looked rusty, rather then shining metallic.

And it's done! This is the end result.

And these are the leftovers.

This set was built online and you can see the recording of the live streaming here. Although and since I guess you do not have all that time to waste, here it is also the building video accelerated in a timelapse format.

If I'd just build this fast...

5. Functionality and playability

As a small set you should not expect much and complex functions, although this a cute and nice playable set with some functions that we should expect from a bulldozer toy.

The functions are all manual and include:

Let's see some of them in more detail:

Driving and steer

In this model the driving and steer includes one differential in the transmission. Although this is different in the details from the way the differential works in a real bulldozer [1]. Nevertheless the differential was introduced in this model to allow  the final drives and tracks to drive and steer in any combinations while keeping the engine rotating.
This is far more realistic than the solution used in the old 8275 Motorized Bulldozer, where the engine was attached to one of the tracks only and these were operated independently. This caused the strange effect of having the engine stopped if the bulldozer had only the track from the right side moving. One could have expected the large 8275 to have space for a more realistic design, including also a differential, but is seems not.

The Front Blade

It lifts up and down as expected, by turning the exhaust pipe in the front, which a nicely done detail.

The blade movement range seems to be appropriate and real, although it uses a solution quite different from real Dozers. Instead of using hydraulics or their LEGO equivalents (pneumatics or linear actuators) it uses a crank shaft to make a couple of fake hydraulics to move in quite strange and unrealistic circular movement.
It's fair to say that at this scale and fulfilling the probable target setting for this model (which may have excluded pneumatics), it would have been really difficult if not impossible to find a more realistic solution - so the compromise came into place...

Another interesting aspect of the adopted solution is that the blade lifting mechanism operates in continuum. If one keeps rotating the exhausting pipe continuously the blade will alternate between its lower and upper position in a cyclic movement.

In conclusion, this function turned to be realized in a quite unrealistic way, but still quite ingenious and convenient at the same time. All in all it serves the purpose and it looks like an acceptable compromise for the model scale, although not doing much in helping children about Authenticity (one of the LEGO Technic fundamental principles) and how real machines work.

The Ripper

Not much to say about this except it works as expected.

The riper could move below the ground line if you play in a soft surface like real soil, and as real life Dozers do.
This function could even raise the rearside of the Dozer entirely, as you can try to see from the image below.
Not so evident because of the track clearance which causes it to come down a bit.

Now you can watch the video below and see all these functions and more in action.

Something else you'd like to know, just drop us your question in the comments to this post.

6. The B-model

The alternative model proposed for this set is something that you may not identify at a first glance, at least I did not.
At start it looked some sort of mining machine in a strange configuration, but as soon as LEGO started to release some extra information at it became clear it is in fact a Trench Digger.

Below the image from one real Trench Digger, for you to get a better idea on what this is.

It is indeed not something we could be expecting, but it introduces at least some diversity to the LEGO Technic assortment.

This includes also two main functions apart the fundamental drive and differential steering (engine also attaches to the differential in the B-model).
These two functions are:
  • Lift up and down of the digging tool
  • Rotation of the digging tool

Once this is not an easily recognizable type of machinery, it qualifies as a suitable candidate for an alternate model, rather then a main model. And so they did it!

    7. Final considerations

    As said this is a nice medium sized model. Apart the controversial blade lifting mechanism it is very pleasant to play with for a set this size.

    This is not a licensed model, hence we cannot say it is based on the real Dozer 'A' or 'B' from this or another brand. Although there are not so many Dozer makers and in the end we could say this is probably inspired in some of the Caterpiller bulldozers. I'm in doubt between D6T and D9T, but leaning more to the D9T. What do you think?

    On a not so positive note, I feel the side view of this 42028 relative empty in some places, as we can see too much through it. Something I didn't remember to feel so strong since the 8416 Fork-Lift released in 2005, but which can be easily repaired in this model.

    BTW... a good sized forklift is something we don't see in the LEGO Technic assortment for quite a long time!

    From the above you can also see what I meant in the beginning of this review, about the missed opportunity to have the yellow micro panels released.
    Thin 1x5 Liftarms with Axle Holes on Ends (11478), in yellow, would have been great as well. If it was possible to produce these in LBG for the 42030 Volvo L350F Wheel Loader, to put them underside totally away of sight, much more sense would have made to release a yellow version for this Dozer...
    If the image is not suggestive enough, the CAT Dozers above that should provide some further help to enlighten the idea.

    Another issue that drives me crazy is the lack of consistency in some colors. This affects particularly the yellow color in LEGO Technic sets. It can go from a vibrant or intense yellow to some shade of greenish yellow.
    It is not nice to put together beams of different yellow shades, and even less when it comes to the left and right versions of the same panel... They do not fit well at all when coming side to side!
    But apparently the need to keep production costs within sustainable limits, forces to open the admissible color variance for the ABS supply a bit beyond the desirable.

    And to finalize I believe you would appreciate to see a coupe of photos from 42028 and 8275, side-to-side.

    Not really comparable if you decide to ask which one is the better...

    8. The Ratings

    Now that's time for a synthesis,
    • Very good price per part
    • Not one single new part. I'm sure it wouldn't have been that difficult to include some 15100 in this!...
    • A great set for something not seen in this scale for a very long time.
    • Alternate model constitutes a real surprise.
    • A couple of interesting solutions applied in this, like the differential usage and the front blade linkage system.
    • The same blade linkage is simultaneously very questionable in itself.
    • Good and addicting playability for a set this size.

    Which with some other observations along this post, I've translated into this.

       as value for the money
       for parts innovation
       for set innovation
       for set design
       for functionality and playability

    Overall rate: Good  

    This is obviously heavily penalised by the fact of not including any new elements. Although I'm still convinced about this set.

    Great for children to play and good for fans to collect!


    Allanp said...

    Thanks for the informative review. As for the model, it's quite nice actually. Of course there are always going to be things we would do different. For me, I would have placed the controls for the blade and the ripper further away from their respective functions, like a hand wheel placed either side of the cabin for each function to make them feel more like technical functions, or of course use pneuma...yeah, you know ;). But at this scale I like the drive train. At a larger scale we could have had planetary final drives but at this scale and price point the differential to the engine at least gives the feel of some sort of transmission which is an improvement over 8275. The crank mechanism of the front blade is unrealistic, but no more unrealistic than LAs and at least here, with the crank solution, you get to build some gearing down and not spend ages twiddling a knob to get anything to move.

    Ryan said...

    I lookd into my collection and the bushes with the receded center exist longer. It was there already with 8265 and 8258. The part can be recognized by the 'LEGO' marking. After that sometimes the part came in a different version without the marking.

    Anonymous said...

    Strange set. B-model looks better than A.

    Paul said...

    Thanks for the excellent review, I am looking forward to the B model.


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