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Hawk Lotus 30 conversion

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wixwacing
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Posts: 1871
Joined: Thu Jul 10, 2008 9:22 am

Hawk Lotus 30 conversion

Post by wixwacing »

LOTUS 30

Static Model Conversion



By Phil Wicks


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At this moment in time there are still difficulties in obtaining some of the classic slot car bodies in 1/32 hard body form. There’s scarcely a week goes by without yet another ‘must have’ body being released. The quality gets better and better and the prices are still tumbling. Some manufacturers like ‘Ocar’ include cast metal parts to add a bit more realism to their kits. Moulded lights too can be expected and now, people like Team Slot are releasing resin bodies ready painted.

So, in this barrage of models there is barely time to get on with much else. Indeed, some of the more difficult tasks get put to one side waiting for a later date to arrive when they will once again be revived and finished. One such project in my pile has been the Lotus 30.

This Lotus 30 was bought probably as long as three years ago to be converted to a slot car for my own enjoyment. It was a well priced eBay win and on receiving the model I opened it up and my jaw hit my chest when I saw what you got for your money! The kit consisted of about ten parts and no screen! The headlamps were a raised moulding on the front wings and the carb stacks looked like two rows of miniature cigarette butts. Apart from that it was fine. A good likeness and reasonable scale. The body too is moulded in good thickness polystyrene and should be quite durable.



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The chassis was to be a donor chassis from an earlier project. I had converted the Hornby Porsche Kit Car and built a brass rail chassis. Since using the easy to work with PCB Chassis I have converted two or three models to this and consequently have spare brass chassis The chassis is basically a ‘ladder’ construction. Two rails run the length of the model and crosspieces of various functions are soldered in to hold axles, guide and motor.

This model has a spring loaded Ninco guide mounted in a matching vertical brass tube. The front axle is of the ‘wixle type, independently rotating front wheels without the slop. Axles are 3/32 Music Wire from the local RC shop and pinion and contrate are the stock Scalextric 9/27 type. The chassis had an NC2 motor but this found its way onto the new Porsche chassis.
The new motor was purchased from local electronic hobby store “Dick Smith”. They are the same externally as the Mabuchi ‘S’ can and differ in the fact that they have precious metal brushes instead of carbons and I suspect the winding is a little ‘softer’ as theThe motor runs fine and is probably best described as a ‘doughy’ NC1. It is just as fast but doesn’t quite have that little bit of zip on acceleration and a tiny bit less motor brakes.


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Initial thoughts were that the motor would come to a premature end via the brushes but not so. I have this motor in four or five scratch builds at this moment which have had good track time and are still running well. I have had one failure in the past but this is still less than the SCX failures experienced!!

Wheels are the excellent BWA alloy wheels. Tolerances are first class and finish is superb and they are fixed by a hidden grubscrew. The inserts are the proper ‘Lotus’ pressed steel wheel replicas also from BWA. Front tyres are SCX ‘Type 7’ and rears are the ‘Ninco 20 x 11 Superacing’ Tyres are a good fit to the wheels and no fettling was required. The rears had a slightly concave profile but soon bedded in.

The body parts were assembled and the floor pan was extended inwards from the bottom of the sills and reinforced. The chassis was offered up and fixing points were extended to get the chassis /body height correct. The small polystyrene discs were glued in place and drilled 1/16th. Once I was happy with everything the body was then primed. As always, it was firstly coated in flat neutral grey acrylic. Blemishes removed and hole for the air ram tubes cut.


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I then marked and drilled the non existent headlamps. This was probably the most difficult part. The holes had to be elongated and the lamps themselves were cut from clear ABS rod the same diameter as the hole width. The external end of the rod was profiled so that when it sat in the horizontal position, it presented a snug fitting clear oval in the lamp holes. These were later epoxied in place after the body was painted and before its clear coat. The sides of the rod were painted green and the rear end silver.

Driver and cockpit detail was a lot of work too. I think a flat drivers tray is fine in sedans and closed models as they aren’t ‘in your face’. But with an open model it always looks not quite right. This must stem from being spoilt by commercial manufacturer sidewinder models that comfortably fit full cockpit detail! So what to do? In the end I built into the body a little cover that fits snugly over the motor and glued it in place. Next was to cut all the cockpit parts to match. The driver lost most of his left side but once in place the protruding parts were painted to match the 3D detail! It is almost invisible to the casual glance!!

Now, the missing windscreen, this is going to be hard! A wrap around screen about six millimetres deep!! Now’s the time that the old Ninco spares packets come into use. The back of the packs contain a large piece of workable plastic. The screen was first cut in thick paper. The clear plastic was covered one side in masking tape and the paper profile was copied on to it. The new screen was shaped at the corners by holding them over a hot 25 watt soldering iron and carefully bending at premarked point. The


reason for this is that cold bending the plastic will result in cloudy corners were the plastic has become stressed. It was then filed and sanded ‘til it was a better than good fit and then kept to one side.


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The body had a coat of Tamiya Acrylic gloss. I mixed their mid green with about 10% yellow to try and emulate the Lotus colour. It may not be an exact match but it does stand out from other models of similar colour. After the green coat I applied a thinned coat of clear. After this cured I then masked the distinctive yellow stripe of the early sixties down the centre of the model. The stripe was sprayed and allowed to dry. The tape was removed after 15 minutes and the body left to cure once more.

Decals, courtesey of Patto’s place, were applied. After a couple of days the final clear coat was applied and the model left for a week. Drivers detail was inserted. Interior detail was painted, New brass carb ram tubes were glued in from underneath. Then the screen was next. The bottom edge of the screen had an even strip of clear epoxy painted on to it with a small paintbrush. The screen was then carefully placed in its resting position using tweezers. Remember, once in place and that was it!

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The whole was left for a week or so to dry out completely. After this the painted wheel inserts were fitted and the whole outer wheel had a coat of clear. Finally, the chassis and body were brought together for the final assembly and voila! One of Mr Chapman’s earlier examples of cutting edge racing technology finished!


Next was the much anticipated bit. The chassis had already been run in another car and been debugged so this was almost to be a formality.

Placing it on Red Lane (see board track review) at my local board track, I set out on a very pleasing experience. The model was well behaved from the start. Cornering was a dream and with the lower rated motor it didn’t take long before I was in a very quick rythmn. As said before, the motor is not quick but the models outstanding cornering ability allowed vital corner exit speeds to be very high by comparison. The Race manager was set to practice and I started to clock up the laps. Opening times came in at the high 7’s and before long were in the mid sevens. A quick dust up on the tyre sander saw the fastest lap time eventually drop to 7.358 secs! This was ahead of some very reputable models.


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I can only attribute this to its very low C of G and the Ninco Superacing tyres on the rear. Both allowed outstanding cornering and grip and the consequent corner exit speeds were phenomenal. The model has been run on Scalextric classic too. Much the same experience. Compared to other non magnet models with superior motors it was difficult to catch and rare to deslot.
Statistics

Overall weight				74.0 grams
Rear axle load				41.0 grams
Front Axle load				33.0 grams
Front/Rear axle weight			44.5% / 55.5%
Wheelbase                               73.0 m.m.
Front Axle width			53.0 m.m.
Rear Axle width				51.5 m.m.
Pinion teeth				9z
Crownwheel teeth			27z
Motor					Dick Smith $1.95 hobby.
This project started out as a time filler but has ended up with probably one of the most overall pleasing models I have made. It is a pretty model and reasonably to scale. It drives excellently and is a classic example of finess winning over brute force!
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When I'm not racing slotcars,
I'm out in the back yard, burning food!!

When I win, it's because of my talent, not my car or my controller!
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