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Howdy, l’il slot car buckaroos. Time for another rip roarin’ tale of slot car chassis scratchbuilding wire weirdness out of the wild west… (the “west” of the FL peninsula, that is…)
A few of the more ordinally-inclined may have noticed a slight jump in the chassis design numbering sequence here…
The 1230 and 1231 designs were adaptations of the more linear and right-angled 1228 design; they were layouts of ideas that I wasn’t sure how to incorporate onto any future 1229-based designs; but once they were drawn out, the light came on and I could see how to do the changes I wanted to make using the 1229 design. Whether the 1230 or 1231 ever get built, who knows…
Next on the list was the 1232, a design based on the 1229 but with the removal of the front axle rails and their variable spring wire tension (VSWT) system. This was done so I could better see where the adjunct superstructure required with the new changes could be arranged. Again, once I started drawing it out, it all made better sense to me, and I was able to move directly into the design and build of the 1233.
(And this appears it will also be the case with the almost-finalized 1234 preliminary design leading to the 1235 design… But that’s another tune for the OWH jukebox…)
The 1233 design incorporates all the same design components as the 1229, with the following alterations:
1) Motor box lateral pans have been lengthened and moved closer to the rear tires.
2) Perimeter wire outer side “pans”, that previously surrounded the inner side pans, have been replaced by triangulated outer wire side pans that are completely lateral to the inner side pans.
3) The addition of two pairs of “pan rails”:
3a) One pair of pan rails projecting from each side of the motor box assembly, running between the front axle rails and the center-guide section, to support each center-guide flanking pan; previously the center-guide flanking pans had been attached to the forward end (at the guide tongue) of the center-guide section.
3b) Another pair of pan rails projecting from the motor box assembly lateral pans, running on each side lateral to the indirect main rails (IMR’s, or for some “z-rails”), to support the inner side pans; previously the inner side pans had been attached to the rear of the front wing assembly.
The structural design changes in Items 1 and 2 above were made to accomplish the functional design change in Item 3, the incorporation of pan rails. On previous designs the center-guide flanking pans and the inner side pans were in effect structural “filler”, with no function except for spacing between adjacent structures. The thought was by mounting these pans using rails running from the rear motor/axle assembly as their own separate components they may exhibit some of the “harmonic dampening” effect that others have mentioned. I’m not going to pretend to be some sort of engineer or physicist here, but I had a fairly good idea what I wanted the pans to do so I could observe the effect it may have on the chassis handling characteristics. In addition, the mounting of the inner side pans on their own rails removes them from the total structure of the front wing assembly and the wire-framed outer side pans along with the body mounting system and the body. Besides, it seemed like it was worth a try, and I’ll try anything…
After playing around with the 1229’s I had decided that the next builds would be 0.039” wire framed chassis; I also opted for the slightly shorter and very slightly lighter “c” dimensions for this chassis, with a 3.875” WB and 4.875” RAX-GPC (no concrete data to support this decision, just still going on a previous “hunch”…).
So, for your perusal I present the 1233-Cc2:
The diagram, included for those who feel like torturing themselves trying to figure out what is attached where, is for a 0.047” wire framed chassis. This is because it is easier for me to draw than 0.039” wire framed diagrams, and I’m basically lazy. I already know what has to be where when doing a build where I switch from 0.047” to 0.039” wire. For all you who don’t, my apologies.
Also, I did take build sequence pictures for this one (so I could look back to see what exactly I did on this one myself!), which I know helps y’all a lot to see what all is going on here. If I get the chance I’ll try to post them up at some later time…
The poop on this scoop:
All framing wire is 0.039”, except as noted: Outer side pan movement restrictors are 0.055” wire in 1/8” square brass tube. The two VSWT bracing wires and the foremost wire of the center-guide section are 0.047” wire. Front-axle rail down-stops and VSWT spring wire are 0.032” wire. Center-guide spring wire, center-guide flanking pan rail spring wires, front and rear indirect main rail spring wires, inner side pan rail spring wires, and inner side pan spring wires are 0.024” wire. The moving “pans” (2x center-guide flanking pans and 2x inner side pan) are 0.039” wire outer frame with 0.024” inner support wires. The four motor box assembly static pans (two forward, two lateral) are 0.010” brass sheet. Guide tongue is a narrowed Slick 7 (S7-25) mounted on a 0.025” brass plate above the center-guide section framing wire. Motor bracket is a modified JK (JK-D3F122) and is mounted at an angle to achieve a non-hypoid gear mesh, but keeping the motor mass as low as possible.
There was another design change that I didn’t address until I got to that part of the build. The rear pin mounts were always spring-wire mounted (and attached to the outer perimeter side “pans”) on previous chassis designs due to the movement of adjacent structures. On the 1233 this is not necessary since they can be attached directly to the triangular outer side pans, and move together.
There are so many components to this 1233 sucker, and particularly the additional four rails (composed of eight wire widths) more than the 1229 that, even composed of 0.039” wire, this is one chunky monkey of a chassis. The pictured roller came in at a whopping 76.4 g! The RTR car tops out at a new record (for me) bloated total of 110.7 g!! That’s even heavier than the 0.047” wire 1229-Ca that was built to be a GT Coupe. But, I’m not going to lose any sleep over this. I’ve stated many times before that for me the total mass is merely a result of component design/function/construction, and is not a criteria itself. It is what it is (so it weighs what it weighs). It’s more how the mass of the various components move individually and in relation to each other when running forces are applied.
So, the question is how did attaching the center-guide flanking side pans and inner side pans to separate rails attached to the chassis rear affect the chassis handling characteristics?
It could maybe do as I hoped and help stabilize the cornering, have no effect whatsoever, or make the thing so unstable as to be undriveable…
Test run:
I got to the King track at SCR-Pinellas today (first time in about two months…) to try this thing out. The yardstick would be the 1229-Cc2 which is the chassis/car I ran at the last GRRR race back in January. The new P-Dog in the 1233 turned out to be somewhat slower straight line than the one in the 1229-Cc2, but lap times were only slightly slower. Right away I was taking a liking to the cornering characteristics of the 1233 chassis. So I put another better/faster motor in the 1233, but it still lacked the straight line speed of the P-Dog in the 1229-Cc2…
But the 1233-Cc2 turned faster lap times…
I always start testing a new chassis with the adjusting screw to the spring wire to the front axle rails (my “VSWT” system) backed out as far as possible, so there is the least amount of tension on the spring wire and the car will be its loosest. Then I start tightening down the screw in increments, gradually making the car “tighter”, until it gets to a point where it becomes too tight and starts to “push” out of the slot in the corners, then back it off to the previous setting…
So, on the 1233-Cc2 here I kept tightening the screw and the car… and the thing just kept getting faster through the turns… through the Deadman, Finger and Ninety, and especially coming up the Donut where this is most noticeable… and it never started to push out… and no chatter… The transition from the right-hand Donut to the left-hand Lead-On was smooth as glass as well…
Admittedly, I eventually just stopped tightening the adjusting screw, because I just wasn’t comfortable driving the car like this… I kept expecting the thing to push out… It didn’t, but I was just not used to the thing… A car is only as good as its driver, and today that was definitely the limiting factor… But I’ll work on that…
As a side note, the P-Dog motor in the 1229-Cd2, which has just been sitting in my box for two months, has decided for no apparent reason to become a rocket… I am at a loss to explain this. Where before it was only as fast as the motor in the 1229-Cc2 (which was turning the same lap times it was two months ago), today it was quite obviously faster down the main straight. This gave the 1229-Cd2 lap times on average about 0.05s faster than the 1229-Cc2…
The 1233-Cc2, with a slower motor than both, ran lap times as fast as the “rocket” 1229-Cd2…
I just need to learn to drive the friggin’ thing.
So, there just may be something to this whole idea of rear mounted pan rails and pans…
Who’d of thunk, huh?
Once again, more questions than answers…
Hope y’all are having fun too!
Rick
Registered User
Originally Posted by CMF3
???
I would have thought just the opposite... less tension = more flex = more bite = "tighter" whereas more tension = stiffer chassis = less bite = "looser"(?).
Are we of the same mind chassis dynamics-wise but differ semantically?
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No…
I think we have the same “semantics” here. What we probably don’t have is the same “chassis” as a reference point…
The only spring wire tension being adjusted here is that going to the front axle rails. (There are other spring wires for other components.)
Decreasing the front axle rail spring tension:
= Less force required to move front axle
= Less rear tire “bite”
= More “loose” (back end slides more) / less “tight” or “pushing”
Increasing the front axle rail spring tension:
= More force required to move front axle
= More rear tire “bite”
= More “tight” or “pushing” (back end slides less) / less “loose”
Keep in mind, on most chassis the front wheels are attached to the same plate/structure that holds the guide; this is certainly NOT the case here, so it has a relatively different chassis dynamic as a result.
Think of it as a “tricycle” (the guide and the two rear tires), but then you are adding two outriggers (the two front wheels) that can be adjusted. The attachment point of those outriggers does matter; in this case they run out from the rear tires.
The other components (such as the main rails, front wings, pans, body mounting) and their movements are not affected (directly) by adjustment of the front axle spring wire, so the overall “flex” of the chassis remains the same. And there are a lot of movements and “flex” to these chassis. Marty calls them “Slinkies”…
FYI Tex… You do realize I got the “idea” to use front axle rails from you… So, people can blame you…
I hope this explanation helps. Happy trails, pardner!
Rick
Registered User
Rick,
You are just too far out there for me to try to absorb all you describe; that is to say, I'm just too lazy. Many words. VERY many words. But needed... I understand. To try and read the words and truly understand the underlying concept takes patience and time; as it is, I don't carve out enough building time for myself. I still have color prints of some of your early designs that I haven't built yet. I wonder if I should even try since your development goes on and on and on(?). Of course, that is to be expected and should continue to be. I suppose building one of your older designs would be a good exercise in trying to come to grips with understanding the underlying concepts of how you isolate different components and movements from one another. Besides, I know I'd have a heckuva good handling car once finished with the build! Someday. Still workin' on my own variation of your VSWT; I'm in the process of building what I think will be the final iteration. Discovering shortcomings in how I implemented things and then figuring out how to preclude those shortcomings has taken some time. Have I mentioned how lazy I am? Even setting aside time to ponder how to fix things is a major accomplishment for me. I'm such a couch potato.
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Rick, very interesting info on your build. I will keep it filled in the brain for the future. Great job and keep the info coming.
Todd
Registered User
As threatened, I finally got around to putting together the build sequence for the 1233-Cc2 chassis. Hopefully this will help anyone trying to visualize where all the weird wires go on this thing. A lot of it is similar to the 1229 build sequence, so if you could follow that one, you’ve got a running start on this one… If not, just look at the pictures and think that I’m completely nuts… I don’t mind…
Sorry for the occasional out-of-focus shot…
All wire is 0.039” unless otherwise noted.
Picture 1: The 4-bend front spanning wire is fashioned, assuring it is flat, and taped in place.
Picture 2 & 3: A second 2-bend wire is bent to fit against its three medial lengths of the first spanning wire, and the wires are soldered together.
Picture 4: (…blurry, Pic 5 is better…) Front Axle Rails; each front axle rail consists of one 1-bend wire (the rear length is longer than needed to allow for a rear axle tube upright bend later) flanked along its forward length on each side by two straight wires; they are soldered together at both ends (not entire length).
Pictures 5 - 14:
Indirect Main Rails (IMR); The indirect main rails ( or “z-rails”) for this build are a 2-1-2 set-up (2- wires project forward from the chassis rear assembly; -1- connecting wire in-between; -2 wires attach to the front chassis assembly). They also incorporate framed areas at the rear-lateral aspect for the addition of static pans later.
Picture 5: The first IMR 1-bend wire is shaped to lie lateral to the front axle rail assembly (the rear length is longer than needed to allow for a rear axle tube upright bend later).
Picture 6: A 2-bend wire is soldered to the rear of the first IMR wire to form the rear of the pan area. Note, the lateral length is longer than needed, and will be trimmed to size later.
Pictures 7 & 8: The second IMR 2-bend wire is shaped to lie adjacent to the forward length of the first; the bends outline the front of the pan area; the two IMR wires are soldered together front and rear.
Note: There is a 0.039” gap between the lateral lengths of the second IMR wire and the wire in Picture 6; these wires are tack soldered.
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Pictures 9 - 11: Three 1-bend wires are soldered to the interior of each pan frame (rear-medial corner, front corner and rear-lateral corner), making all sides 2x wires wide.
Picture 12: The single straight IMR connecting rail is soldered to the forward portion of the first two IMR wires.
Note: The rear ends of this IMR wire and the next IMR two wires in Pictures 13 and 14 should have clearance with the second IMR wire’s forward edge at the pan area.
Picture 13: The first of two 1-bend wires that will attach to the chassis front assembly is soldered to the rear of the IMR connecting wire (but is not soldered to the front spanning wire at this time).
Picture 14: The second of the two 1-bend wires that will attach to the chassis front assembly is soldered to the rear and front portions of the adjacent wire (and, also is not soldered to the front spanning wire at this time).
Picture 15: The 7/32” D x 1.40” L rear axle tube is jigged into place.
Note of no importance: I still get odd comments about my Champion jig, mostly from those other odd souls who still have theirs... Sure, being a working stiff again I can afford some new fancy jigs, but this has always worked fine for my purposes… And it just wouldn’t be the same without it…
Picture 16: The rear axle tube upright bends are made on the IMR assemblies.
Picture 17: The floating front wires (3x, medial) of the IMR assembly that do not attach to the front spanning wire are trimmed to ensure clearance; the IMR assembly is then soldered to the rear axle tube and front spanning wire.
Picture 18: The rear axle tube upright bends are made on the front axle rail assemblies.
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Picture 19: The forward ends of the front axle rails (that do not attach to the front spanning wire) are trimmed to ensure clearance, and then they’re soldered in place to the rear axle tube and rear portion of the adjacent wire of the IMR’s.
Picture 20: The jig is removed.
Pictures 21 – 25:
Front Wing Assemblies; consist of five wires each.
Picture 21: The first front wing assembly wire is a 1-bend wire soldered to the lateral-most IMR wire; this outlines the rear of the front wheel well.
Picture 22: The second front wing assembly wire is a 2-bend wire soldered to the first wire and forward surface of the front spanning wire; this outlines the front of the front wheel well. (I keep these longer than needed along the front of the chassis for alignment purposes; they are trimmed off at chassis completion.)
Picture 23: A 2-bend wire is soldered to the first two wing assembly wires.
Picture 24: A 1-bend wire is soldered in to reinforce the first and third wing assembly wires.
Picture 25: The final 1-bend wing assembly wire is soldered in to reinforce the second front wing assembly wire, the front spanning wire and the attachment point of the IMR’s.
Pictures 26 – 28:
Inner Side Pan (ISP) Rails (Part 1 of 2): The ISP rails consist of four wires each that extend from the rear-lateral static pans’ framing. Two of four wires are fashioned at this time, one is soldered in place.
Picture 26: The first 2-bend ISP Rail wire is soldered at the front and lateral sides of the lateral static pans’ framing to the adjacent IMR wire, and filling the gap on the lateral side (see Picture 28 for close-up).
Note: The forward length of this wire does not run all the way to the front wing assembly.
Picture 27: The second 1-bend ISP Rail wire is fashioned, but is only used as spacing and is NOT soldered in at this time.
Note: The forward length of this wire does run all the way to the front wing assembly, and will be trimmed to fit later.
Picture 28: The excess length of the lateral side wire of the lateral static pans (from Picture 6) is trimmed to size, using the second ISP Rail Wire (from Picture 27) to define its length and angle.
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Pictures 29 – 33:
Outer Side Pans: The Outer Side Pans consist of four wires each, extending from the front wings assembly.
Picture 29: The first 1-bend lateral outer side pan wire is soldered to the rearward front wheel well wing assembly wire. The rear end of this wire is trimmed to clear the lateral wire extending from the rear-lateral static pan framing.
Picture 30: The second 1-bend medial outer side pan wire is soldered to the forward- medial aspect of the first wire.
Note 1: The left Outer Side Pan is shown completed for reference.
Note 2: To define the medial edge of the outer side pans, the second ISP Rail wire, another piece of 0.039” wire and a strip of 0.25” wide brass are used as spacing.
Note 3: The rear edge of this wire is trimmed to ensure clearance with the second ISP Rail wire (that is being used for spacing).
Picture 31: The third 1-bend medial outer side pan wire is soldered to the medial aspect of the first wire and the rearward end of the second wire (ensuring clearance with the second ISP Rail wire).
Picture 32: The fourth/final straight medial outer side pan wire is soldered to the lateral aspect of the second wire and the rearward end of the third wire.
Picture 33: Both outer side pans complete.
Pictures 34 – 36:
Inner Side Pan (ISP) Rails (Part 2 of 2):
Picture 34: The third 1-bend ISP Rail wire is tack soldered to the end of the first wire, allowing for clearance with the IMR wires and the outer side pan wires.
Picture 35: The second 1-bend ISP Rail wire (fashioned in Picture 27) is trimmed to fit and soldered in place.
Picture 36: The fourth straight and short ISP Rail wire is soldered to the rear aspect of the forward length of the third wire.
Pictures 37 – 41:
Inner Side Pans: The Inner Side Pans consist of two 0.039” wires and six 0.024” wires each; they are optionally fabricated at this time, but are NOT attached to the ISP Rails at this time.
Picture 37: The two 1-bend 0.039” wires that define the perimeter of the inner side pans are fashioned to fit between the ISP rails and the outer side pans; they are tack soldered together at their forward and rearward points. Note: these should be made to allow a tiny gap between them and adjacent wires.
Picture 38: Two 2-bend 0.024” wires that supply cross-support are tack soldered into place.
Last edited by CMF3; 04-09-2014 at 10:51 AM.
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Picture 39: Two 1-bend 0.024” wires that reinforce the forward and rearward points of the 0.039” wires are tack soldered into place.
Picture 40: Two straight 0.024” wires are tack soldered in place along the remaining inner sides of the 0.039” wires.
Picture 41: The 0.039” wires and 0.024” wires are soldered together around the entire outer perimeter of the inner side pans. The two inner side pans are placed aside; they will not be installed until Picture 86.
Picture 42: The front axle rail down-stops are installed. Two pieces of 0.032” wire are soldered side-by-side for a distance shorter than the distance from the front spanning wire to the center-line of the front axle. Carefully these are soldered atop the foremost portion of the front-axle rails (only!), ensuring they rest atop but no solder gets onto the front spanning wire (or adjacent IMR’s). A wire is soldered atop each of the forward edge of the two angled portions of the front spanning wire. These wires act as lateral movement restrictors for the guide and the front axle rail down stops.
Note 1: It is easier to make the down-stops longer than needed, and to cut the forward excess length off after installing (see Picture 43).
Note 2: The forward front-axle upright will be placed atop the down-stops at a later step.
Picture 43: Four small 0.024” bump-wires are soldered to the forward floating portion of the IMRs (1 each) and to the adjacent connecting IMR rail (1 each), along the front axle line. These bump-wires will abut against the underside of the spanning up-stop wire for the center-guide section / center-guide flanking pan rails / IMR’s (see Picture 61); the “bump-wires” are added as spacing to the connecting IMR wires where the spanning up-stop wire will soldered in place to keep it at the same level as the bump-wires. (Note: No bump-wires are attached to the front axle rails.)
Picture 44:
Center-Guide Flanking Pan (CGFP) Rails: These each consist of two 1-bend wires soldered together at their forward and rearward lengths, and soldered to the rear of the adjacent front axle rails.
Note1: The forward edge of the CGFP Rails are spaced approximately 0.30” behind the front spanning wire.
Note 2: The space between the two forward-medial ends of the two CGFP Rails is spaced approximately 0.20” (enough for 5x 0.039” wires).
Pictures 45 – 51:
Center-Guide Section (Part 1 of 2):
Pictures 45 – 51: Center-Guide section framing
Picture 45: The center-guide section is started with two straight wires tack-soldered together perpendicular to each other; the first short wire is parallel and just behind the center length of the front spanning wire and is 0.047” wire (0.047” wire is used to give the guide tongue a slight upward tilt later); the second wire runs rearward from the first along the chassis center-line, and is longer than needed to ease installation (and is trimmed to size later). No portion of the center-guide section is attached to any other part of the chassis framing until later (Picture 59).
Picture 46: Two 1-bend wires are soldered to the first two wires to complete their connection. Note: The length of these wires parallel to the center-line wire is only about 0.75”, and not the entire length of the structure.
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Pictures 47 - 49: Three 1-bend wires are soldered to each side of the forward center-guide section to complete the guide tongue attachment platform.
Picture 50: A 2-bend wire is soldered (only) to each L-shaped wire. Note: A piece of 0.039” wire (not shown) is used to space this wire from the center-line wire.
Picture 51: A 3-bend wire is shaped to fit from each of the spaces along the rear of the center-line wire, paralleling the 2-bend wire from Picture 50, and beyond the rear axle tube; the excess length is used to make a rear axle tube upright later (Picture 58). It is soldered to the center-line wire and the 2-bend wire from Picture 50 only.
Pictures 52 – 56:
Center-Guide Flanking Pans: The center-guide flanking pans consist of two 0.039” wires and four 0.024” wires each.
Picture 52: The two 1-bend 0.039” wires that define the perimeter of the center-guide flanking pans are fashioned to fit within the space between the center-guide section framing and the CGFP rails; they are tack soldered together at their forward and rearward points; note: these should be made to allow a tiny gap between them and the surrounding wires.
Picture 53: A 2-bend 0.024” wire that supplies cross-support is tack-soldered into place.
Picture 54: A 1-bend 0.024” wire that reinforces the rearward point of the 0.039” wires is tack soldered into place.
Picture 55: The final two 0.024” straight wires, are tack soldered into place. The 0.039” wires and 0.024” wires are soldered together around the entire outer perimeter of the center-guide flanking pans.
Picture 56: The center-guide flanking pans are soldered to the front of the CGFP rails. Four small 0.024” bump-wires are soldered to the forward CGFP rails(1 each) and to the medial side of the center-guide flanking pans (1 each), along the front axle line. These bump-wires will abut against the underside of the spanning up-stop wire for the center-guide section / center-guide flanking pan rails / IMR’s (see Picture 61). Forward of the bump-wires, four small pieces of 0.039” wire are soldered on as medial-lateral movement restrictors.
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Pictures 57 – 51:
Center-Guide Section (Part 2 of 2):
Picture 57: Guide tongue installation
Pictures 58 – 59: Center-Guide section installation
Picture 60: Center-Guide section bump-wires
Picture 57: A piece of 0.025” brass plate is tinned and soldered atop the front of the center-guide section (it is easier to make this piece larger than needed and trim it to fit). The guide tongue (Slick 7 S7-25) has been narrowed to ensure it will not contact the front-axle rails, tinned and then soldered in place.
Picture 58: The rear axle tube upright bends are made on the center-guide section.
Picture 59: The center-guide section is soldered into place, attaching to the rear portion of the adjacent CGFP rail wires, front axle rail wires and the rear axle tube.
Picture 60: Two small 0.024” bump-wires are soldered atop the framing of the center-guide section along the front axle line.
Picture 61: The 2-bend spanning up-stop wire for the center-guide section, CGFP rails and IMR’s is soldered in place; it is placed along the line of the front axle, which will be suspended above it, and rests atop the bump-wires.
Pictures 62 – 65:
Motor Box Extension framing:
Picture 62: The excess length of the center-guide section center wire is trimmed off.
The motor box extension is started with two wires tack-soldered together. The first is a 1-bend wire just behind rear of the center-guide section, and is made to allow a tiny gap between itself and the adjacent center-guide section wires. The second is a straight wire running from the angle of the first rearward along the chassis center-line; and again longer than needed to ease installation (and is trimmed to size later).
Picture 63: A 1-bend wire is soldered to each lateral length of the first wire and the rear length of the adjacent center-guide section wires; it too should fit with a tiny gap between itself and the forward portion of the adjacent center-guide section wires.
Picture 64: A 2-bend wire is soldered to each side of the center-line wire and to the adjacent rear length of each wire from Picture 63.
Picture 65: A 1-bend wire is soldered to each of the two forward lengths of the wires from Picture 64. A 1-bend wire is soldered to each of the two forward lengths of the wires from Pictures 63.
Pictures 66 – 67:
Motor Box framing
Picture 66: The excess length of the motor box extension center-line wire is removed.
The 1-bend (with rear axle tube upright bend) inner motor box wires are soldered to the rear axle tube and to the rear of the motor box extension wires.
Note 1: This motor box is sized for FK-type motors; as a matter of spacing, I use a 0.5” wide piece of 0.064” brass flanked on each side by a length of 0.047” wire, for approximately 0.6” spacing.
Note 2: Where the IMR’s, front axle rails and center-guide section rear axle tube uprights attached to the front of the rear axle tube, the motor box rear axle tube uprights attach to the rear of the rear axle tube.
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Picture 67: The straight (with rear axle tube upright bend) outer motor box wires are soldered to the rear axle tube and inner motor box wires.
Picture 68: The excess lengths of all the wires connecting to the rear axle tube are removed.
The 4-bend (2-plane) gear-guard wire is shaped and soldered to the rear portion of the inner motor box wires (behind where the motor bracket face will be placed).
Picture 69: The 2-bend rear axle tube spreader wire is soldered atop of the gear-guard and to the ends of the rear axle tube.
Picture 70: The center portion of the rear axle tube is removed. The motor bracket (JK-D3F122) is modified.
Picture 71: The modified motor bracket is positioned so the motor will be angled such that the shaft of the motor will be perpendicular with the rear axle while keeping the front of the motor flush with the bottom plane of the chassis, and soldered into place; this allows for a better gear mesh than with an offset, or “hypoid”, motor mounting gear mesh, while keeping the mass of the motor as low as possible.
Picture 72: A short wire is soldered atop each side of the motor box; this helps to cradle the motor and affords easier points to solder the motor in place.
Picture 73: Four pieces of 0.010” brass sheet are cut to fit the two lateral pan sections of the IMR wires and the two quadrangular pan sections of the motor box extension, and soldered in place.
Picture 74: The control box for the variable spring-wire tension (VSWT) system for the front axle rails is soldered atop the center-forward wires of the motor box extension; the control box is a 1/8” square brass tube cut 5/8” long with a 1/16” hole drilled in one side 5/32” from the front of the tube. (A FK-type motor mounting screw will be tapped into the drilled hole and used as the adjuster for the VSWT.)
Picture 75: A 2-bend 0.047” bracing wire is soldered to each side of VSWT control box, atop the motor box extension and to the back of the chassis; this wire helps to stiffen the motor box extension, counteracting the forces exerted on it by the VSWT spring wire.
Picture 76: The outer side pan movement restrictor box is soldered to each lateral edge of the rear-lateral static pans framing; the restrictor box is 1/8” square brass.
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Picture 77: A short 1-bend piece of 0.055” wire is soldered to each of the outer side pans so they extend into the movement restrictor box; they should just make contact with the inner side of the square brass tube.
Picture 78: The rear of the outer side pan restrictor box and wire are trimmed to allow for clearance with the rear tires.
Picture 79: A 0.024” spring wire is soldered to the center-guide section so that it rests atop the spanning wire up-stop. Note: This spring wire is set to “zero-tension” when in its “static” or at-rest position.
Picture 80: A 0.024” spring wire is soldered to each CGFP rail so that it rests atop the spanning wire up-stop. Note: These spring wires are set to “zero-tension” when in their “static” or at-rest position.
Picture 81: A 0.024” spring wire is soldered to each forward floating section of the IMR’s so that it rests atop the spanning wire up-stop. Note: These spring wires are set to “zero-tension” when in their “static” or at-rest position.
Picture 82: This picture shows the five spring wires installed in Pictures 79 – 81.
Picture 83: A total of four 0.024” bump-wires are soldered to each forward-lateral corner of the motor box extension and to the ISP Rails.
Picture 84: A total of four 0.024” bump-wires are soldered to each medial and lateral edge of the inner side pans.
Note: The bump rails in Pictures 83 and 84 are all aligned.
Picture 85: A total of four 0.039” lateral-medial movement restrictor wires are soldered to each rearward medial and lateral edge of the inner side pans.
Picture 86: The inner side pans are soldered in place, attaching at the front of the ISP Rails.
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Picture 87: A total of four 0.039” lateral-medial movement restrictor wires are soldered to each forward medial and lateral edge of the ISP Rails
Picture 88: A 1-bend up-stop wire is soldered to the motor box extension and rests atop the bump-wires on the ISP Rails and inner side pans.
Picture 89:
a) A 1-bend up-stop wire is soldered to each side of the chassis main framing and extending over the rear of the IMR and the rear of the inner side pan.
b) A 0.024” spring wire is soldered to each of the two rear floating portion of the IMR’s, to rest atop the rear up-stop.
c) A 0.024” spring wire is soldered to the rear-medial side of each of the two inner side pans, to rest atop the rear up-stop.
d) A 0.024” spring wire is soldered to the forward portion of each ISP Rail, to rest atop the raised forward up-stop.
e) A 0.024” spring wire is soldered to the forward portion of the lateral side of each of the two inner side pans, to rest atop the raised forward up-stop.
Note: All spring wires are set to “zero-tension” when in their “static” or at-rest position.
Picture 90: Front Axle Spanning Uprights: The two 4-bend (2-plane) front axle (FAX) uprights are shaped and soldered in place; the front FAX upright is soldered atop the front axle rail down-stops; the rear FAX upright is soldered atop the front axle rails.
Picture 91: A 2-bend wire is soldered atop the base of the rear FAX upright.
Note: This spanning wire should not contact the center-guide section spring wire and two CGFP Rail spring wires below it. (This wire is to allow contact points for the VSWT spring wire.)
Picture 92: Two small (0.125”) pieces of 3/32” square brass tubing are soldered to each side of the rear FAX upright base spanning wire. These are the forward contact points for the VSWT spring wire.
Picture 93: Each rear body mount pin tube (1/16” brass tube with collar) is soldered atop a 1-bend (L-shaped) 0.032” wire that is soldered to the outer side pan.
Picture 94: Each middle body mount pin tube (1/16” brass tube with collar) is soldered to the outer side pan just behind the front wheel wells.
Picture 95: Each front body mount pin tube (1/16” brass tube with collar) is soldered atop the front wing assembly forward of the front wheel wells.
Picture 96: The 5-bend 0.032” VSWT spring wire is formed and inserted into the VSWT control box and brass tubes atop the rear FAX upright base spanning wire. An FK-type motor mounting screw is tapped into the VSWT control box to adjust the VSWT spring wire tension.
Addendum:
And some of you thought my old stuff was overly-complicated… Lots of pages of notes before I even thought about starting this build (yes, I use notes, ‘cause I ain’t no real scratchbuilder…).
But honestly, this was a lot of fun to build…
Any questions? You know what to do…
Rick
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