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Hello Folks, One of our fellow site members is a huge CanAm fan, and loves the Monogram McLaren M6, but, unfortunately, has not managed to make one work to his satisfaction. He contacted me and asked if I would be willing to take a stab at overhauling one, with the objective to have it run with his other CanAm cars.

Having done a few Monograms in the past (Lola and McLaren) and being very pleased with the way they turned out, I agreed to build one for him.

Unfortunately. I did not take pictures of every step. but, I should be able to describe them well enough.

The first pic. is of the bare chassis......it is in the process of being filed/sanded to clear the inside of the body, and allow some body movement. It is important to file/sand off the raised "cups" on the chassis body mounts, to allow the body posts free movement on the chassis posts....in the pic, you can see where this has been mostly finished....it still needs a final clean up. On the rear axle mounts, you can see where I have temporarily inserted a brass tube (3/16" id.) which will hold some 3/16" od. single flange oilites. By positioning the tube at a slightly higher position in the rear axle uprights, I will raise the position of the rear axle, effectively reducing the ride height, and lowering the cg.

The motor mount locating holes were also filed/sanded a few thou. on their bottom edges, to allow the motor to sit slightly lower in the chassis (the bottom edge of the motor now protrudes just below the bottom surface of the chassis)......not much, but, "everything counts..in small amounts" !!



The second photo, shows the axle tube from a side profile.....I have enlarged the rear axle cups to accept the tube, but, have tried to maintain a "C" shape to the cups, which holds the tube from moving upwards...this really helps hold the tube in place. Try to achieve a very small tolerance between the mating surfaces as most glues are terrible gap fillers..(read weak!!)



I have slightly enlarged the front axle bushing holders to accept a 1/8" od. tube. "U" shaped cutouts are just fine here as the tube will be held with styrene plates glued to the outside of the chassis and the tube. (I used some 30 thou. styrene with a 1/8 hole drilled into it for the side plates).

When securing both the front and rear axle tubes, I used a jig with set up blocks to ensure that both axles will be parallel, and, on the same horizontal plane.......this is critical for a good handling car, and by doing this you eliminate any small variances in the depth of the bushing cups. and negate any minor chassis twists. (You can "bake" the chassis, but, the Monogram chassis is very thick and difficult to straighten, and, most chassis' made of plastic do have a memory, and over time minor twists can reoccur. As well, you are then relying on the bushing cups to be identical in height left to right........this is where the adjustable front ride height systems (slot-its set screw etc.) are worth their weight in gold, as these systems permit minor left to right adjustments to overcome these issues.

A new guide was installed, and a small piece of square styrene tubeing was glued in to route the lead wires through.



The finished rolling chassis........a 7.5mm NSR pinion and an 18mm Slot-it spur fit perfectly, meshed very well, and allowed good clearance for the spur/track.....(the 7.5mm pinion/18mm spur is a very good option for any folks looking to improve these cars......it lets you use a slightly smaller rear tire diameter and still allows reasonable spur/track clearance).

A quick coat of Tamiya flat black spray made it purdy!!, and small urethane washers were glued to the tops of the chassis body mount tabs...these really help eliminate vibration/noise.

A chunk of lead was added to the pocket where the magnet originally lived.



The body mounts were trimmed to square and lower the body, BWA/Dart inserts were painted installed, and she is ready to go.



As it sits it handles very well and is quick, no doubt, as I was asked to install a Piranha motor.....to be honest, I think it would be better with a slightly milder motor. On my track (wood) it is very close to my well sorted Slot-it Chaparral/Alfa's...it is only when overdriven that the very short guide lead of the McLaren rears its ugly head. The McLaren has a guide lead some 3/8 shorter than the Slot-it Alfa (also a very short guide lead car), and this is not the hot ticket on my track, which is fairly fast/flowing.

Anyway, I really had fun with this...it was certainly worth the effort......just hope the new owner feels the same ;)

Cheers
Chris Walker

Nice, clean work and it looks the business too.

It's always interesting to follow your tuning skills. Thanks for posting this.

Another very nice build! Any "anglewinder hop" on your wood track? I ask because that looks like a very stiff chassis, which sometimes help with anglewinder hop.

Allan

Excellent work on the car and excellent write-up to describe what was done and how it was done: exactly what we have come to expect from you Chris!

I have also done some tweaks to my M6 but to a lesser degree than your work:

* Slot.it rear axle with Sloting Plus Victors self aligning spherical bushings
* I kept the original motor and pinion. If you thought the Piranha is overpowering..... I also found that a 19mm Slot.it spur meshed very well indeed.
* I coincidentally also used BWA wheels and inserts on the rear. Kept the original wheels up front.
* I lowered the body by trimming the body posts. The first thing to interfere was the engine detail onto the motor so I did a bit of relief grinding there. Like you: removing the "cups" from the chassis mountings is one of the first thing I do to cars that have them! As I have mentioned before: I really like your trick of adding urethane "absorbers" on the body mountings: something that I will definitely have to start retrofitting!
* Added a Slot.it screw in universal guide. Instead of moving the front axle I used spacers on the guide to set the correct front wheel ride height.
* Also added some lead.

In terms of resulting performance I have not been as successful as you (my simpler approach is just not as good BUT the big difference: your skills are just WAY better than mine!). But it still runs very nicely. Mine is still a ways behind my Slot.it Alfa (7.572 vs. 7.151 seconds lap). For added perspective: this lap time would have put the car in 15th position out of 25 cars in qualifying for the recent Ford/Ferrari proxy on Luf's track. Not great but not bad either.

Your work here has now goaded me into doing some more "tweaking" to see if I cannot improve on this time!

Great job as always!

Alwyn

Interesting project. I tried lowering the front wheels on one of mine but didn't make any modifications to the rear. You have given me some ideas.

Nice Chris,
Love it when anyone takes the time to make a revagram a runner, I brt it is a smooth runner! I have a couple myself that are go to cars on club nights, granted we don`t do any real racing. But they will hold thier own with the slot.it can ams in no mag form. 18K H&R Hawk motor is my choice.
Mark:

Chris -
I bought 10 of the red Monogram 85-4841 McLaren M6B #11 Lothar Motschenbacher cars a few months back when Electric Deams had them at 10 for $180. I've been using them for different bodies, etc. I still have 4 or 5 if you need some more to experiment with or want to cannibalize parts.

OK, I actually did some remedial work on mine since yesterday! Remarkable what a bit of prompting can do. Work now done:

* When I last took the car to the track I found that the front tyres had completely deformed: seems like the oils had evaporated and the tyres went all odd shaped. I temporarily grabbed some urethanes from Luf for the evening: these sort-of fit but not great. I think this held the car back quite a bit. I now found some better fitting fronts and trued and profiled them. The fronts were never trued before and the car did suffer from a bit of "headshake" (to use a motorcycling phrase!). Hoping this will cure it now.
* After truing, the new front tyres were slightly smaller in diameter than the old ones so I appropriately re-shimmed the guide. The front of the car now sits a bit lower: looks better!
* I was not happy with the truing of the rear tyres so I pulled off the old ones, glued on a new set of urethanes and trued them better. While I was at it I slightly reduced the rear tyre diameter so that the rear dropped a touch as well to match the front. Like the new, lower stance and I am assuming (hoping?) this will improve the handling a touch as well.
* I was not happy with the weight on the car so I fiddled with that a bit as well.

Thanks for the incentive to do this Chris: will report back on how it now runs after our Friday races.

Alwyn

Thanks for this. It seems like I have a job to do too.

Thanks for sharing these mods! I have been struggling with the rear wheels and getting decent tires that fit. I didn't consider tubing the rear end, that's a good idea.

If you had not prompted me into putting the finishing touches to my M6 I don't know when I would have gotten to it!

And as for the results: WOW!!!! Unlikely as it may seem, this is now one of my fastest non-podded cars! I wrung a best lap of 7.008 seconds out of it this evening: this is like seriously fast! For perspective: this is faster than the fastest qualifier in the recent Ford-Ferrari proxy! This is also faster than all but one car's best race lap, and that was Chris's brilliant Slot.it GT40, with which I did a 6.888 lap.

And it is not just the fact that it is fast but even more how composed and comfortable it is at that speed. It really corners like it is on rails (or maybe guided in a slot?) and it felt like I could turn blindingly fast lap after blindingly fast lap all evening long.

Such a narrow, small, technically rather crude little car going this fast: who'd a thunk it?!

So thanks again Chris for being the instigator to get me to put the finishing touches to the car: it turned out great!

Alwyn