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Trumpeter
Multiple Gun Motor Carriage M16
Trumpeter Kit No. 00911
Part 2: Chassis/Supension/Running Gear
1:16th Scale

Trumpeter
Chassis:

TrumpeterThe main chassis as mentioned is in the form of two metal side frames with plastic cross members added to form the basis for the whole kit.

There was a small issue in that the right frame was slightly twisted at the front which caused a few minor issues fitting the front cross member (part C10) and the transmission that has to be trapped between the chassis frames as you join these together.

The rear most cross member (part B6) is held in place with a couple of screws and this ensures the back is perfectly aligned with all the other parts glued in place with cyanoacrylate or epoxy and using a slow curing glue will allow you to line everything up before the glue cures.

Due to the slight twisting of the right frame the two locating pins in the front cross member (part C10) didn’t mate properly and forced the front of the frames too far apart if they did, I cut off the right locating pin from part C10 and temporally fitted the chassis extensions (parts X1, X2) and the winch plate (part X16) to ensure the front of the chassis frames were the correct distance apart. You should also check that the whole chassis is aligned correctly as it is easy to have some twisting due to the fit of the front cross members not being that precise, another reason for temporarily fitting the chassis extensions and winch tray as mentioned to help with the alignment.

You should also watch when assembling the transmission (in step 1) as the illustrations show the rear fly wheel fitted to the transmission but this part is not identified in the instructions and is actually part Z28, the instructions don’t show this part being fitted till step 6. Also watch the direction of the transmission as you fit this to the chassis as it is shown in three different directions in the step 1 illustrations which may cause some confusion during fitting?

Suspension:

TrumpeterThe two front suspension springs are moulded in one piece with good clean leaf spring detail but there is a large mould seam to be removed from down the centre line of the springs which will need some care, the springs are attached to the chassis frames the screws for a solid fit. As mentioned above you have to watch the screws to be used as the rear screws are labelled PM2x6 and the front screws labelled PB2x6 and it’s easy to mix these up if not careful?

The front axle has the differential in two halves with separate wheel mountings that include the vinyl cups and this allows the wheels to be steerable after assembly when joined with the steering rod. The detail on the axle/differential is basic at best with the diff in particular devoid of any detail; most notably the bolt heads holding the diff halves together and other details and these will have to be added as their absence is quite conspicuous in this larger scale.

Other details not provided are the steering arm, the shock absorbers and linkages as well as other detail on the axles and diff as mentioned for a very plain looking assembly that gives plenty of scope for adding the missing details.

The rear axle differential has a little more detail as it has the bolt heads around the diff housing but lacks the lower drain plug which is easily added, there is also the brake lines to be added to both the front and real axles for additional detail. The rear axle is again screwed to the chassis for greater strength and you should fit the drive shaft (part Z22) between the transmission and differential as you fit the drive axle in place. The drive shaft is also lacking many bolt heads and other details that can be added if you wish but this is hard to see after assembly you could leave as is?

Front Wheels:

TrumpeterThe front wheels have the large vinyl tyres that have well done combat tread pattern but no sidewall embossing and thankfully are completely round and there are two large circular plastic parts that sort of represent the inner tube which are supposed to be fitted inside the vinyl tyres. But as the vinyl is quite hard and not really flexible fitting these large parts inside the tyres is all but impossible and if you get them in there you get the grand prize. It’s best to save yourself a lot of aggravation and just ignore these parts (A15, A18) as they are simply not needed and the wheel rims are also in two halves, the outer rim with excellent rim bolt detail that only needs the tyre valve added from thin sprue to finish off and the inner rim.

These two rims have to be glued together from either side if the vinyl tyre as you can’t fit the tyre over the rims due to the rigid vinyl and you will have to squeeze the two rims halves together until the glue has dried as the tyres try and force these apart as the fit is quite snug. Clamping these together overnight with a liberal serving of glue for the strong join to make sure they don’t pop apart at a later time would be a good option.

The brake drum includes the wheel hub that pokes though the outer rim and this again has good details with the rear brake drum plate designed to just fit into a collar trapped inside the brake drum which allows the wheel to rotate and this fits together quite nicely with the wheel fitting to the wheel mounting on the end of the axles and if careful with the glue the wheels do rotate and steer so you can easily add articulation to the front wheels.

Drive Sprockets:

TrumpeterThe drive sprockets as mentioned are moulded in two halves and are quite impressive with all the ribs and cut-outs in the sprockets nicely done with just a bare minimum of cleanup needed, this mostly consists of the moulding seams around the outer faces. But there are some annoying pin marks around the outer edge of the sprocket between the ribs that will take a bit of effort to remove.

The central hub cap is a separate part that traps a small cup inside the sprocket hub to take a large pin allowing the sprocket to rotate after assembly so make sure you don’t glue this cup (part U25) to the hub.

The drive tooth disc is a separate part trapped between the two sprocket halves and this has a small notch on the back to align the teeth but there is a problem here in that the notch is in the wrong place resulting in the drive teeth not lining up correctly with the cut-outs in the sprockets. You will have to enlarge this notch a little to allow the tooth disc to be rotated a little to line up correctly and it’s easy to miss this until too late when assembling the sprockets as I almost did.

When fitting the sprocket halves together you have to take care as you can easily fit these the wrong way around resulting in the cut-outs not lining up correctly as there is no locating pin or other indication other than the instruction illustration to show the correct alignment of the cut-outs.

The large brake drum (part A17) fits to the back of the inner sprocket halve and a large pin is slipped through this to be glued to the cup (part U25) trapped previously inside the outer sprocket and due to the larger sizes here it’s fairly easy to glue these together without getting glue where it shouldn’t go allowing the sprockets to rotate nicely.

The assembled sprockets are then glued to the axle mountings and you should make sure the glue has fully dried before adding the tracks to avoid any problems.

Idlers:

TrumpeterThe rear idler mounting are again quite simplified with the spring unit having a separate end plate with the correct indentation and central hole but the moulded on spring needs the moulding seam carefully removed and in this larger scale will look far more convincing if you cut away the moulded on springs and replace with thick wire for better definition.

The springs include the idler tensioning rods but the end bracket has a small ridge on the back and does not sit flush with the chassis frame as it should while the idler mounting (part C8) has contours that simply don’t match those of the rear thing and may need to be remodelled for a better appearance if you wish.

Most conspicuous by its absence is the large rear idler brace that goes from the idler mounting to the back of the chassis and this part will have to be scratch built if you want your idlers to match the real thing.

The idler mountings are also attached to the chassis with screws for a robust attachment but you will have to file off a small ridge from the chassis where the forward springs go for a nice flush fit.
 
Moving to the idlers themselves these have both the idler wheel halves moulded in one piece which is rather impressive but there are quite a few moulding seams around the rims and some fine flash inside some cut-outs to be removed as a consequence but this is small change compared to the excellent detail on the idlers.

The idler hub cap is a separate part but don’t glue this until after fitting the idler to the mounting as the idler is attached using a screw through the centre of the hub for a robust attachment which is then hidden by the hub cap.

Bogie units:

TrumpeterEach bogie unit is made up of no less than 38 plastic parts plus the separate vinyl tyres but there is quite a bit of work needed both in assembly and to add the missing details if you wish to depict the bogie housings correctly?

The main bogie housing has the large mounting bracket and four parts for the housing and you have to add the volute springs and crab assembly (part A1) as you fit the housing parts together. After gluing the housing together there are prominent join seams that have to be filled and sanded as the actual housing is a single casting and this takes a little effort especially for the join to the main support and to ensure you don’t destroy the casting numbers included on the sides of the housing.

There should also be a large hole with raised lip added to the bottom of the support bracket which is seen on every half-track bogie unit and the omission of this in this large scale is again puzzling but the bogie housing does have the oval cut-out applicable to all purpose built M16s. I added this by drilling a hole in the housing and adding the lip from wire bent to shape.

The road wheels have the ‘rubber’ section in vinyl but there is a mould seam line around one edge of this which is very difficult to remove and positioning this to the inside when fitting the tyres will help to keep it less conspicuous. As you assemble the road wheel units it’s best to sit these on a flat surface while the glue dries to ensure the wheels are even as its easy for these the be twisted as they are only joined together by the central connecting rod if you want the wheels to rotate.  

Attaching the bogie arms that hold the wheel units in place is a little tricky as they are only joined by two thin connecting beams (parts A13) and this results in a rather flimsy assembly and it is better to also glue arms to the bogie housing for a more robust assembly ensuring all the wheels are level as you do this.

The upper return roller has the two separate end brackets, two part rollers and connecting rod (axle) that fit together easily but you will have to add the bracket hex bolts as these are only represented by the bracket locating pins. Also note there should be the exhaust pipe bracket added to the right return roller bracket as this is not included in the kit.

This bracket is a thin angled L shaped bracket with U bolt to hold the exhaust pipe and is easily made from thin card and wire and again why this isn’t in a kit of this size is another puzzle as it is well documented and a quite prominent feature.

The assembled bogie units are again screwed to the chassis for a robust attachment with the large cross tube (part A12) added between the two bogie units as these are attached to the chassis. There was a problem fitting the cross tube as this was too long and I had to trim about 1mm off each end for it to allow the bogies to fit properly to the chassis.

Tracks:

TrumpeterThe tracks on the Half-track series of vehicles are basically rubber bands with steel belt inserts and are not separate linked track as with many AFV tracks with these fitting tightly around the drive and idler wheels without any track sag on properly tensioned track. The vinyl track supplied on the kit represents this track type with the outer blocks, smooth inner surface and track guide plates although some of the details are a little basic such as the pads being slightly too small as are the inner track guide plates but they give a fairly good impression of the tracks overall.

The track lengths are joined by ten pins and the track will glue together with plastic cement (I used Tenax-7R successfully) but it’s also a good idea to heat weld the pins together for a stronger join as the tracks are under a little tension when fitted around the suspension.

Before fitting the track you should ensure the glue on the drive sprockets are fully dry and it’s best to also leave the idlers off until fitting the tracks and slip the idlers inside the tracks and then screw in place as you can’t stretch the tracks to fit over the drive teeth if the idlers are attached first.  

There is an issue when fitting the tracks as they are quite rigid and don’t sit well around the suspension components and some tinkering will be needed to get the tracks to sit down properly along the top run in particular.




Page created October 30, 2008