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CMF3 1237-series design and build progression


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#126 Eddie Fleming

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Posted 27 May 2020 - 12:05 PM

Time will tell how well it works but I agree with you the Lotus looks a lot better. The best looking of the Mclaren M7C is the CL. But yes I like the Lotus.

 

Stay well stay safe and hope to see you in the fall at Fast Eddie's


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#127 crazyphysicsteacher

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Posted 30 May 2020 - 10:26 AM

Rick, I will bet you find moving the pivot point for the triangles backward is a huge improvement to off the corner bite.

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#128 Rick Moore

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Posted 16 June 2020 - 05:06 PM

A228.2-e3

 

Another F1 build, as promised, or as threatened, depending on your frame of mind…

 

Over in the CMF3 JFF scratchbuilding thread there was the A401-01 Lotus 56B build, a cool looking F1 car that has no applicability to organized rules racing. But there were elements of that chassis design that are applicable to the 1237-Series that warranted investigation, in this case the rear motor/drive section. The A227 and A228 designs employ a modified version of that A401 rear motor/drive assembly, mostly changing the A401’s anglewinder drive to the A227/A228 in-line drive. The more notable shared feature, as on the A401, the rear axle tube uprights for the A227/A228 are frame superstructure, a change of the usual rear axle tube uprights which are frame wires with bends to attach to the tube.

 

For the A227 and A228 the front half of the chassis are, respectively, the “same” as the A219/A225 (with single center main rail) and the A220/A226 (with diverging main rails). And, again and for the same reason noted with the A226 build, I opted to skip the single main railed A227 and move directly to the diverging main railed A228 build.

 

The A228.2-e3:

 

A228.2-e3-00ae.jpg

 

A228.2-e3-01ae.jpg

 

A228.2-e3-02ae.jpg

 

A228.2-e3-03ae.jpg

 

A228.2-e3-04ae.jpg

 

A228.2-e3-05ae.jpg

 

 

First pic shows the completed chassis frame, and that it does not directly carry the rear axle tube.

 

The sissy bar for the A228 is interchangeable, consisting of two 1/16” tubes attached to the rear axle tube with 0.032” wire; the sissy bars on which the body rests are 0.032” wire (instead of the usual single 0.024” wire) that are inserted into the tubes. A set of sissy bars of differing lengths will allow me use different bodies, such as the Oleg Lotus 63 again, or any of the McLaren M7 bodies.

 

Some of you, or maybe very few if any, may wonder if there will be a retro F1 version of the A401. Well, it cannot be ruled out. And some new CanAm designs are making it even more probable… We’ll see…

 

Testing, Update:

 

I finally got to Fast Eddie’s Raceway a few weeks ago on May 27. DZ was there testing also (a warning to other GRRR racers…), so I tried to stay out of his way (LOL).

 

I was able to get some first test runs in on the new 1270.2-Cb3 and 1271.2-Cb3 CanAm cars, and some much needed additional test laps on the 1258.5-Cb3. All three showed potential, turning some of the best laps in the CMF3 stable for the evening, with the out-of-the-box 1271.2-Cb3 turning the best gutter lap times on both Red and Black. Not bad.

 

I only ran a few cursory laps with the A226.2-e3 F1 car, preferring to get this A228.2-e3 finished before doing a more proper shakedown, but it seemed to be fine.

 

(On an even more pointless note, I ran some of the newer JFF cars for a few quick fun laps. The A401-01 Lotus 56B is a fun little rocket, and looks great zipping around; thinking I might put a little faster pony in it. And the 1405-01 Chaparral 2D may very well have become my new favorite JFF car; it’s a kick to drive and handles surprisingly well, despite the utter mish-mash 1405 chassis; looks pretty cool too.)

 

Most likely skipping a trip to Fast Eddie’s this week, weighing the known PPE-protected exposure to COVID-19 at work (as the number of patients, and requisite X-ray exams, continue to rise…), and limiting myself going out in the general population with minimal face-mask protection… yeaahhhh… Maybe next week…

 

“We need to get this man to a hospital right away.”

“What is it, Doctor?”

“It’s a large building full of sick people…”

 

Stay safe, and have fun, to all you vectors.

 

Rick / CMF3

 


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#129 mickey thumbs

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Posted 16 June 2020 - 11:32 PM

And hands off the fomites!


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Mike Vernon

#130 Rick Moore

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Posted 25 July 2020 - 10:53 AM

1273.2-Cb3

 

As warned in the JFF thread, the poop is really going to hit the fan here… and a lot of it… I think we need a bigger fan…

 

Test runs of the 1270.2-Cb3 and 1271.2-Cb3, though limited, gave the green light for the next design builds in this 1237-Series “1270 sub-set”; in which there are four more designs: the 1272, 1273, 1274, and 1275.

 

First things first. The 1270, 1271, 1272, 1273, 1274, and 1275 all have the same new rear/drive assembly, along with the basic 1237-Series front spanner and “side pan” assemblies. For the main rails:

1) The 1270, 1272, and 1274 have the single center main rail;

2) The 1271, 1273, and 1275 have the forward diverging main rails, with the “iso-guide” mount in between.

 

I refer to 1270, 1272, and 1274 as “Inverted-Y Frames”, and the 1271, 1273, and 1275 as “X-Frames”, since that is what the center of the frames look like (viewed front-as-top to rear-as-bottom).

 

The final differences in these six designs comes with the buttress rails:

3) The 1270 and 1271 have the relatively same buttress rail configuration as all of the 1259-and-earlier chassis.

4) The 1272 and 1273 move the buttress rails to the extreme lateral, just medial of the side pans.

5) The 1274 and 1275 have both sets (four total) of full-lateral and medial buttress rails.

 

I have had some lingering questions about the location of the buttress rails. The 1270-thru-1275 chassis designs were created in part with the hope of investigating those questions to some extent. Of course, my expectation going in is that I’ll have more questions than answers going out…

 

The next step in this group of chassis was to move the buttress rails as far lateral as they’d go, right out to the “side pans”, so the next build would be the 1272 or 1273. I had recently built the JFF 1406-01 with full lateral buttress rails to help sort things out (under the Porsche 917K, a narrow frame with short wheelbase and big tires, despite which the 1406-01 runs extremely well). I’ve done enough testing between the 1254 vs 1256, 1259 vs 1258, and even limited test runs on the 1270 vs 1271, to know I have a definite preference for the chassis having the forward diverging main rails with the “iso-guide” mount, so I opted to skip the 1272 and build the 1273, in the current rage “b” dimensions, of course.

 

The 1273.2-Cb3:

 

1273.2-Cb3-01ae.jpg

 

1273.2-Cb3-02ae.jpg

 

1273.2-Cb3-03ae.jpg

 

1273.2-Cb3-04ae.jpg

 

1273.2-Cb3-05ae.jpg

 

 

And a pic of the chassis with an unpainted Parma 1050-B Ti-22 Short Narrow-Nose to show how it, my body of preference for these short “b”-dimension frames, mounts up on one:

 

1273.2-Cb3-06ae.jpg

 

 

Obviously, with the buttress rails and FAR’s moved laterally, the dynamic pans (0.024” wire framed 0.010” brass sheet) on the 1273 are significantly larger than on the 1271. This was inherent in the design variation, and had to be considered as such. My thinking (WAG) was they would help mitigate any negative effects of the more lateral placement of the buttress rails… who knows… Besides, since the 1270.2-Cb3 and 1271.2-Cb3 both came off the build block at about 97 grams, there would probably be plenty of wiggle-room in the overall mass for the bigger dynamic pans. The 1273 has 0.032” brass plate for the rear static pans instead of the usual 0.010” brass sheet pans, to offset some of the additional forward mass, and making the buttress rail articulations easier to attach.

 

However, I’ve not even bothered to get this one RTR yet because…

 

Testing? Not yet. Besides the pandemic pandemonium, I’m holding off until I get the next one in this series sub-set, the 1275.2-Cb3, completed ASAP… Get the 1273 and 1275 into RTR at the same time… I want to do a proper 3-way analysis of the buttress rail set-ups, and since I only have a limited number of laps on the 1271.2-Cb3, with minimal prior testing to skew the analyzer… which is me… and some say I’ve been skewed for years (still better than being skewered…)… Seemed like a good idea, or a good excuse, whatever… works for me…

 

Chris/Crazyphysicsteacher had asked in a post after the 1270.2-Cb3 about the medial versus lateral placement of the FAR’s for which I did not have a definitive answer, just an operating WAG. Possibly prophetic on his part, the comparison of the 1271.2-Cb3 and 1273.2-Cb3 (along with the 1275…) with their respective medial and lateral placement of the buttress rails with medially attached FAR’s should add some insight to this question… or maybe not… or add more questions… who knows… also seemed like a good idea…

 

Keep an eye on that fan…

 

Rick / CMF3

 


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#131 Rick Moore

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Posted 04 August 2020 - 10:38 AM

1275.2M-Cb3

 

More poop for the fan…

 

The next build in the 1270 sub-set is the 1275, which, as noted before, I wanted to have completed ASAP to make possible 3-way test runs with the 1271.2-Cb3 and the 1273.2-Cb3. As noted in the 1273’s post, the 1275 has two pair of buttress rails, for a total of four buttress rails, with two on each side, one pair fully lateral adjacent to the side pan rails as on the 1272/1273, and another pair medial running the same as on the 1270/1271 (and the 1259-and-earlier chassis).

 

Again, I’m skipping the single center main rail 1274 and building the 1275 with forward diverging main rails with “iso-guide” mount.

 

This “dual buttress rail” configuration produced additional options for the front axle rails (FAR’s), of which three symmetric versions would be given designations (M, L, and D) at this time:

1275.2M: FAR’s attached/medial to the medial buttress rails only;

1275.2L: FAR’s attached/medial to the lateral buttress rails only;

1275.2D: four FAR’s, two per side, attached/medial to both the medial and lateral buttress rails.

 

I’ll leave out the other possible “alphanumerical” configurations, as well as the asymmetric variations; those three should be enough confusion for now. I opted to go with the “M” configuration on this first 1275 build so it would resemble the 1271.2-Cb3 in this regard, and make comparison between those two more meaningful. Depending on how the 1273.2-Cb3 fits into this mix will contribute to determining when and if the 1275.2L-Cb3 and/or 1275.2D-Cb3 get built…

 

During the previous 1273.2-Cb3 build I became aware what looked good on paper for the 1275 may not be so good when it came to the build. To assuage any misgivings and possible annoyances, I did a redraft of the 1275 layout, moving the medial side pan rails a little more laterally, narrowing the side pans, but ensuring there would be plenty of room for the pairs of buttress rails, along with any combination of FAR’s, and being able to get all the wires in the rails to go where they were supposed to go during the build... Once I started building the 1275 I’d see if I: 1) had made the right decision; 2) could have left things alone; 3) made it all worse, or: 4) it was all utterly hopeless and an exercise in futility. The joy of scratchbuilding.

 

As it turns out, the redraft worked. Better to be lucky than good, futility notwithstanding.

 

Poop/pictures. The 1275.2M-Cb3:

 

1275.2M-Cb3-01ae.jpg

 

1275.2M-Cb3-02ae.jpg

 

1275.2M-Cb3-03ae.jpg

 

1275.2M-Cb3-04ae.jpg

 

1275.2M-Cb3-05ae.jpg

 

 

And a side-by-side-by-side of the 1271.2-Cb3 (left), the 1273.2-Cb3 (center), and the 1275.2M-Cb3 (right):

 

1271-1273-1275-ae.jpg

 

 

Like the 1273, the 1275 has 0.032” brass plate for the rear static pans, and, again, should help offset some of the additional mass from the additional buttress rails. But, where the 1273 has larger dynamic pans, the 1275 has dynamic pans (0.024” wire framed 0.010” brass sheet) that are the same size as on the 1271.

 

I put the previous 1273.2-Cb3 and this 1275.2M-Cb3 into RTR trim at the same time. Off the workbench the 1273.2-Cb3, from the previous post, came out to 100.6 grams, and the 1275.2M-Cb3 came out to 101.9 grams. Hunh? About a gram more than I guess-timated for both. In any case, there won’t need to be any lead added to these two just to make the 100g you-know-what…

 

Testing:

 

To say the least, there is still a lot going on in the real world I have to take into consideration and make priorities for, which means test runs are still a wait and see thing, but at least I have these ducks in a row if/when the opportunity to get over to Fast Eddie’s Raceway to get in a few laps presents itself. I’ll update the testing as appropriate…

 

What’s next?

 

The 1275.2L-Cb3 and 1275.2D-Cb3 remain possibilities in this portion of the build sequence, but as I noted above they are contingent upon getting in some test laps on the 1271.2-Cb3, 1273.2-Cb3, and the 1275.2M-Cb3. However, I have two more designs on the drafting table, the 1276 and 1277, that are offshoots in the 1237-Series are not reliant upon any additional testing of previous designs / builds, including the 1270 - 1275’s, and are probable candidates for being next. Subject to change. Check your local listings for time and date…

 

Whole lot of poopin’ goin’ on…

 

And watch your step.

 

Rick / CMF3

 


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#132 old & gray

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Posted 04 August 2020 - 11:33 AM

Rick,

 

Given your occupation and the current state of the world I'm happy to see you posting and not mentioning having any health issues.

 

Keep on building, I'm trying to follow your logic.

 

Bob


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#133 Rick Moore

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Posted 04 August 2020 - 06:36 PM

Thanks, Bob. Your concern is much appreciated, probably more than you know. It’s been a challenge, and that’s as nice as I can state it… Knock on wood…  :dash2: 

 

Speaking of a challenge, good luck with that following the logic thing… even insanity has its own warped logic… 

 

Rick / CMF3

 


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#134 Rick Moore

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Posted 27 August 2020 - 02:13 PM

Testing Update; 1270 Sub-series

 

Since I haven’t been making those regular Wednesday evening trips to the raceway, and with a lot of the previous builds needing test laps as well to sort things out, initial tests laps for the 1271.2-Cb3, 1273.2-Cb3 and 1275.2M-Cb3 were encouraging, but limited. The 1270.2-Cb3, while also encouraging, was far too loose going through the Hillclimb’s “low bank” (the 180 below the high bank), so it got a tear down, reset, and another set of tires. I bought a bunch of stuff at the raceway that night, and came home to realize I forgot the one thing I needed more than anything (the note still sitting on the workbench, having failed to have me not forget the item, instead upon my return reminding me I’m an idiot), so I went back the following Wednesday (and bought what I needed, duh) and was able to get in some laps where I could concentrate more on the 1270 Sub-series cars, and this time with some fairly equal test motors in these new dogs.

 

All four handle a lot better than I expected. A lot. My thinking was they would be “edgy”, but instead they are very stable, consistent and predictable, and very forgiving of mistakes (in many cases, to my surprise, staying in the slot when trying to push the limit). They do have their differences, but the similarities are stronger characteristics. The 1271.2-Cb3 was the fastest on Orange (turning many of the fastest laps of the night, and the outright fastest), followed by the 1270.2-Cb3, the 1273.2-Cb3, and the 1275.2M-Cb3. On Red it was the 1270.2-Cb3 just ahead of the 1275.2M-Cb3, then the 1273.2-Cb3, and the 1271.2-Cb3. On Black it was the 1273.2-Cb3, then the 1275.2M-Cb3, the 1271.2-Cb3, and the 1270.2-Cb3. This may help:

 

Orange: 1271.2-Cb3, 1270.2-Cb3, 1273.2-Cb3, 1275.2M-Cb3

Red:      1270.2-Cb3, 1275.2M-Cb3, 1273.2-Cb3, 1271.2-Cb3

Black:    1273.2-Cb3, 1275.2M-Cb3, 1271.2-Cb3, 1270.2-Cb3

 

Not sure if there is any rhyme or reason to all that, but I’ll sort through it; and more testing for sure. If I had to pick one of these to race in those set-ups, it would’ve been a tough decision, but I probably would have gone with the 1273.2-Cb3. I’m trying to remember if the thing ever came out of the slot, and, looking at the body, I’d say no.

 

All in all, not bad. And it definitely piques my interest to build some more 1270 Sub-series chassis…

 

But, the 1276 is already a “work in progress”, and is the first of the 1277 Sub-series…

 

So much poop, so little fan…

 

Have fun!

 

Rick / CMF3

 


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#135 Rick Moore

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Posted 27 August 2020 - 02:27 PM

1276.2-Cb3 (aka 1276.s0.2-Cb3)

 

Fetch!

 

My initial inclination was to not include this chassis, the not-as-yet designated 1276, as a 1237 Series build, but as the design progressed it contained enough of the 1237 Series’ design elements to at least warrant consideration for inclusion… that was until I subsequently designed another chassis, the not-as-yet designated 1277, and any remaining hesitation went out the door, not so much as a design progression step in the series, but by mere chance on the drafting table, and, this is going to sound weird even for this thread, because the 1276 is an “intermediate visualization”…

 

Probably best not to dwell on that description; let’s just blink, shake our heads, and move on.

 

The 1276 was born out of the Just-For-Fun A401-01 Lotus 56B F1 chassis. Regarding the A401, Eddie Fleming (this is half his fault) had asked if I had ever built a CanAm chassis with the aft-to-fore converging main rails that met directly behind the guide mount, to which I answered “no”. That was partly inaccurate, as there had been the 1211-C, a CanAm chassis based on the 1203, that did have those main rails, but also had rails that ran from them out to the front wings. (The 1219 Series, with the exception of the 1226, had main rails of various forms that converged to just lateral of the guide mount). With this realization, and not above chasing the occasionally thrown stick, I drew up two “sports car wide” chassis with A401-type main rails: a complete design for the 1406-01 Porsche 917 that got built and is posted over in the JFF thread, and; some preliminary doodles of the not-yet-1276 retro CanAm…

 

Looking at the rough draft at the time I got the thought this converging two main rail “1276” design was an oddball in the mix of mostly single center or diverging main rails in the 1237-Series, but was not so dissimilar as the center main rail 1226 chassis had been amidst the converging main rail designs of the 1219-Series. So, maybe…

 

Then, some weeks later, came the at-the-time-unrelated not-yet-1277 doodles and subsequent design… at which point the not-yet-1276 would have its design completed, which quite unintentionally merely consisted of removing two lines from the not-yet-1277… That pretty much nailed these two designs down in the design sequence together, and at which point they got their official 1276 and 1277 monikers with inclusion into the 1237-Series. Besides the 1276, the 1277 design would also lead to the 1278, 1279, 1280, 1281, and 1282 designs, creating yet another sub-series in the 1237-Series, the 1277 Sub-series (so named not as a matter of ordinal progression, but because the 1277 is the base design for all the others).

 

Hopefully you’ll be able to better see how and/or why the 1277 design spawned the 1276 into the sequence, and why the 1276 got built first, after the 1277 gets built when you have some more pictures to reference. Any further written description at this point would make the dog tilt its head and say, “Aarrooo?”

 

This dog chased the stick. The 1276.2-Cb3:

 

1276.2-Cb3-b002ae.jpg

 

1276.2-Cb3-01ae.jpg

 

1276.2-Cb3-02ae.jpg

 

1276.2-Cb3-03ae.jpg

 

1276.2-Cb3-04ae.jpg

 

1276.2-Cb3-05ae.jpg

 

 

What cannot be seen in the pictures, and another reason I wanted to work things out with the 1276 build, is the chassis frame construction sequence. I’m probably not the only person who will tend to get “stuck” doing something the same way over and over, again and again. At some point something may come along that requires us to rethink and change our routine… and possibly even grudgingly, evoking the old adage, “You can’t teach an old dog new tricks.”

 

I have been building these 1237-Series all-wire chassis frames using a basic sequence of front spanner assembly, to main rail(s), to rear assembly, to buttress rails, to side pans / front wings for so long as to be second nature. My little screw-up on the 1262 Sub-series got me thinking about and looking for alternatives, where with the 1270 Sub-series I switched the side pans and buttress rails in the sequence. With the 1277 Sub-series I knew going into the 1276 build there were a few areas I wanted to take stock during the build and reevaluate the best way to proceed. This would lead to a major revision of my old comfortable this-then-that; the resulting sequence for the 1276 (applicable to the 1277 Sub-series) still started with the front spanner, then to first-phase main rails, to side pans / front wings, to buttress rails, to final-phase main rails, to rear assembly.

 

What can be seen on the 1276, the 1277 Sub-series designs started with a shortened rear motor / drive assembly, the shortest thus far in the 1237-Series, approximately 0.25” shorter than the 1237/1241’s. This necessitated the relocation of the side pan restrictors.

 

On the 1276.2-Cb3 the buttress rails, and the adjacent FAR’s, are at the max-lateral position, just medial of the side pan rails. This configuration was used on the 1406-01 and the 1273, and was used on this initial 1276 in anticipation of the initial 1277 build.

 

However, there are quite a few options on the 1276 design for the placement / number of buttress rails, not unlike on the 1270 - 1275 chassis. This is why the 1276.2-Cb3 has the alias alphanumeric ID of the 1276.s0.2-Cb3. The “s0” designate an “s” for symmetric, and “0” for initial base-line buttress placement (full lateral). There is also the possibility of adding a center buttress rail between the two main rails, which would add a “c” to the mess, for example, 1276.s0c.2-Cb3. Another 1276 variation of consideration is the incorporation of the “iso-guide” mount; for the 1276 there is a minor design/build alteration, different from the previous iso-guide chassis (1256, 1258, 1271, 1273, 1275), that would allow for an iso-guide mount; ID-wise it would be designated by an “i”, for example, 1276i.2-Cb3 or 1276i.s0.2-Cb3…

 

For those poor souls who have tried desperately to follow the CMF3 chassis ID system, this gives:

 

#### (iso-guide) . (buttress configuration) . [FAR configuration] – [class] [dimensions] [wire size]

 

At this time it is not worth wasting any more time describing all the possibilities, including both “s” symmetric and “a” asymmetric, leaving their description for such time as they become physical realities.

 

The dynamic pans (0.024” wire framed 0.010” brass sheet) between the main rails and the buttress/FAR rails simply fill this space depending on the buttress/FAR configuration. (An additional removable “rattle pan” between the main rails is another option that also can be incorporated into the 1276, to make it easier to use the chassis as either a CanAm class or GT Coupe class car, but this was not included with this initial 1276 build, preferring to keep it “simpler”, as it was complicated enough already...)

 

Testing:

 

No. I haven’t even bothered to get the 1276.2-Cb3 into RTR form. As soon as I got the sissy bar and unpainted body on, that was that... and started in on the 1277…

 

Besides, once again I want to wait until I get the 1277 done before making one of those general population excursions to F-Ed’s Raceway and doing the first test laps. Though testing of the 1276 and 1277 are at this point largely independent of one another, both represent significant departures within the 1237 Series that it just seemed prudent to get the initial tests in at the same time. As always, we’ll see, subject to change, results may vary, all sales final, watch your step, you can’t get there from here, so long and thanks for all the fish…

 

I warned y’all there was going to be a lot of poop hitting the fan in this thread… Wait till you see the 1277…

 

Sit… Good boy…

 

Rick / CMF3


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#136 Rick Moore

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Posted 03 September 2020 - 10:38 AM

1277.2-Cb3 (aka 1277.s0.2-Cb3)

 

“The puffin sipped at his herbal tea, and sighed, ‘You can’t get the buttons these days’”.

 

After all the confusion trying to describe the what-and-why with the 1276, I’ll apologize up front here if I only make matters worse with the 1277. Hopefully, at least as a matter of optics, you’ll get some idea where this cart is careening. When you see the main rails on this monstrosity, you should get the idea… maybe… maybe not… it doesn’t matter… or I could just be nuts… I’m fine with any or all of those possibilities…

 

The 1277 was one of those “you’re supposed to be going to sleep” ideas. You know, those annoying ones you actually have to get up out of bed and scribble something down so you don’t forget. Looking at it the next morning it quickly became a “you’re supposed to be doing something else”, and I laid out the initial rough draft… And then…

 

A picture being worth a thousand words, here’s the final draft for the 1277.2-Cb3:

 

1277-b-000ae.jpg

 

 

Now for some of those thousand words…

 

The design of the 1277 has both the diverging main rails of chassis like the 1256, 1258, and 1271, and the converging main rails of chassis like the 1406, and 1276…

 

And, as alluded to in the previous build post, THIS is why the 1276 got included in the 1237-Series, and why it got built before the 1277. Conceptually, or “visually”, it would have looked like something was missing in the progression if I had just jumped from the diverging main rail 1255/1256/1257/1258/1271’s to the 1277; I needed the converging main rail 1276 in between, before having both converging and diverging rails on the 1277…

 

…, or essentially as a V (diverging) and inverted-V (converging) laid atop each other, the result of which, as seen in the above diagram, is a chassis main rail structure that looks like two X’s side by side (XX versus those previous chassis with a single X)… or some may see a rhombus / “diamond” with four triangles on its sides… or, if you stare at it for a while, you can see the rails as two crossing parallelograms… or… As a matter of warning, staring at it for any length of time is not advised, the word of experience; but, for my part, the more I stared at it the more it intrigued me, and the more I liked it.

 

“I took the strangely glowing ticket from the giant crane fly, and turned to get onto the train. ‘Hurry’, he hissed, and then before my very eyes changed into a splendid cream bun.”

 

You can see from the 1277 design above that simply removing the full length of the two diverging main rail lines gives the previous 1276 design. For the truly bored and/or ambitious of you, simply by removing other main rail lines from the “XX” on the 1277 design, entire length or half length lines, other designs besides the 1276 become possible, and thus far has yielded the symmetric 1278, 1279, 1280, 1281, and 1282…

 

Besides this new main rail configuration, everything else is 1237-Series style. The 1277.2-Cb3:

 

1277.2-Cb3-b002ae.jpg

 

1277.2-Cb3-01ae.jpg

 

1277.2-Cb3-02ae.jpg

 

1277.2-Cb3-03ae.jpg

 

1277.2-Cb3-04ae.jpg

 

1277.2-Cb3-05ae.jpg

 

 

The term “cross-eyed” keeps coming to mind…

 

So, compared to the example of an 8x or 9x wire 1237-style single-center main rail, the 1277 has four intersecting 3x wire main rails forming eight shorter segments. The 3x wire layout was the minimal build structure, and sounds “flimsy” in and of itself; however, except at the middle of the XX, at any cross-section of the main rails there are four 3x wire rails, or in total 12x wires, which is more than other 1237-Series single-center I, iso-guide V, inverted-Y, or X-frame main rails.

 

As on the 1276.2-Cb3, the 1277.2-Cb3 buttress rails / FAR’s are at the max-lateral position, just medial of the side pan rails.

 

Also, as on the 1276, and applicable to all 1277 Sub-series designs, there are a host of possible variations and versions to the 1277, including an “i” iso-guide version, with differing/additional “s” symmetric or “a” asymmetric structures having numeric designations; thus, this symmetric “s” basic “0” version 1277.2-Cb3 is also known by the more complex moniker of the 1277.s0.2-Cb3.

 

Poop… fan… I warned you…

 

Finally got the 1276.2-Cb3 in RTR trim along with this 1277.2-Cb3. Respectively their off the slab RTR masses came out to 99.6 grams and 99.9 grams. Because I was more interested in seeing the inherent chassis characteristics initially, I didn’t bother to add any dreaded-lead to either as of yet; pretty dang close anyways.

 

Testing:

 

I expected the 1277, and to a lesser extent the 1276, to have a little more of the characteristics of “stiffer” chassis, like the 1267.2-Cb3 or 1262.9.2-Cd3, but by no means not as much as they exhibited with these first test laps (?!), and especially considering I kept the frames minimal structurally (?!?!). Stranger was the 1276 more so than the 1277 (?!?!?!). And both so much so I was questioning whether I’d blown the set-up on both of them. Did some quick fiddling with them at F-Ed’s to dispel or duplicate what I was seeing (no hallucinations, flashbacks being a rip-off). I have some hypotheses as to the why’s, so I’ll start with a tear down of both, with a lot of prodding and bending, put them back together and test some more…

 

Curiouser and curiouser.

 

What’s next (?!?!?!):

 

At this point there are a lot of options: The 1277 design has spawned so many notes and scribbles that I need to sit down and spend time just sorting it all out. After that, and last night’s tests, in the 1277 Sub-series the 1278.2-Cb3 would be next for test and observation purposes (and help with those hypothetical notions), before proceeding with the 1279, 1280, 1281, or 1282. In the 1270 Sub-series there are four chassis that are high on the curiosity list, the 1272.2-Cb3, 1274.2-Cb3, 1275.2L-Cb3, and 1275.2D-Cb3. And I wouldn’t mind building some “c” or “d” dimension versions of some of the designs that have already been “b” built, like the 1258 for starters. Also some of the modified configurations of existing designs are “maybe’s”. All have good reasons for being next. And that’s just the CanAm class chassis… Of course, when things get a bit muddled in the 1237 builds I can always spend some time building a JFF while I sort things out… Cool! Yes, I’m having way too much fun with this, and I need to get a life…

 

“By this time the suitcase was getting very heavy. So, I rested on a grassy knoll, and took a peek inside. As I opened it, out burst a fountain of many-colored butterflies, rainbow game counters, chess pieces, laughing cutlery, tiny chairs and tables, and plates covered with exotic fruit.”

 

Psilly rabbits.

 

Rick / CMF3

 



#137 Eddie Fleming

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Posted 03 September 2020 - 01:30 PM

I love the look of the 1277 Rick. Looks like a mad man,, Uh make that genius did the layout.

 

One question, the inside pans look to be on sliders that would make them shift fore and aft under breaking and acceleration is that so?. I may have overlooked that in your narrative.


Eddie Fleming

#138 Rick Moore

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Posted 03 September 2020 - 02:56 PM

Hey, Eddie. Weird looking thing, ain’t it?

 

Let’s see if I can get all this pan stuff spelled out here while we’re on the subject. In the 1237-Series I use four types of pans added to the wire frame:

 

Static Pans; soldered directly into the frame

Semi-Static Pans; soldered indirectly to the frame using “larger” wire

Semi-Dynamic Pans: soldered indirectly to the frame using “smaller” wire on one side with movement limiters on the opposite side

Dynamic Pans; non-fixed, suspended within the frame

 

All the Dynamic Pans on the 1237-Series chassis are sliders/rattlers. The mount tubes attached to the pan are 1/16 x 0.006” thin wall (0.047” interior diameter) with 0.032” wire hangers attached to the frame; this gives approximately 0.015” vertical play as well as the fore-aft slide. Starting with the 1241’s the direction of the slide was angled (relative to the centerline) to be parallel with the buttress rails. (Sorry, I don't have a good clear detail pic of the dyn pan tube/hangers.)

 

Rick / CMF3

 

 


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