Corrosion resistant, light weight TJ frame
- Thread starter rowen01960
- Start date
OP
Last nights efforts ... Notional (JK) Bracketry is mostly located ... it will be adapted for clearances and bonding surface definition .. then finally I can start FEA meshing ...
The TJ Series consists of a STD geometry frame (TJOE) allowing a straight re/re of TJ Body and systems, the TJ25 provides new Rod mounts for 2.5” Lift, while the TJ40 will provide new Rod mounts for 4.0” lift.
The LJ Series Series consists of a STD geometry frame (LJOE) allowing a straight re/re of LJ Body and systems, the LJ25 provides new Rod mounts for 2.5” Lift, while the LJ40 will provide new Rod mounts for 4.0” lift.
Both of the above series will have options to extend Frame Rails before and after the Axle.
The TJ Series consists of a STD geometry frame (TJOE) allowing a straight re/re of TJ Body and systems, the TJ25 provides new Rod mounts for 2.5” Lift, while the TJ40 will provide new Rod mounts for 4.0” lift.
The LJ Series Series consists of a STD geometry frame (LJOE) allowing a straight re/re of LJ Body and systems, the LJ25 provides new Rod mounts for 2.5” Lift, while the LJ40 will provide new Rod mounts for 4.0” lift.
Both of the above series will have options to extend Frame Rails before and after the Axle.
OP
Colours are pure product differentiation ... for both Frame Series Type and variants within the series ... I would appreciate feed back/suggestions as I am creatively colour blind ... 
... of note ... the pigments will be imbedded in the matrix ... not painted ... the frames can be recoated with Polyurthane Colour Coats.
... of note ... the pigments will be imbedded in the matrix ... not painted ... the frames can be recoated with Polyurthane Colour Coats.You appear to be missing the crossmember for the rear shocks and front lip of the gas tank skid. Looks interesting so far though. A big concern for a trail jeep along with the Inability to weld on long arm brackets is the impact and abrasion resistance of the frame. On the trail I fairly regularly land hard on frame rails or the tcase skid. I then drag that rail over the rock it landed on. How. Would this material stand up to that kind of treatment?
—
There must have been a time
when we could have said no.
—
There must have been a time
when we could have said no.
OP
I normally leave secondary design elements such as non-crash/impact XMBRS until the HDPTs (Suspension Locating Points) are “warm & fuzzy” , the “Dot Connecting” surfaces such as suspension brackets are then defined the strain contours to either the initial Frame Rail Geometry (shown) or modifications of same.
The JTOE/JT25/JT40 are complete frame assy as “mostly” imaged. The suspension geometry/Engine/Trans/Steering mounts will be predefined (as per drawing) and not modifable by the end user ... the intent is to be a “Bolt-on build”
For End-Users that wish the JTOE/JT25/JT40 to have other than the pre-specified geometry, Special adapters for all brackets will be installed lin lui of, to allow Machined Metal Fittings to be attached to the Composite Frame. This ensures that the Frame is allways receiving Forces/Moments in the correct locations up to the defined limits of the Frame/Brackets/Adapters.
The Lower Frame between Axles will have a User Replaceable Cover/Layer for Sliding/Scraping/Gouging ... 2-3G GVW “Loadings” onto single Frame Rails will be simulated and if required demonstrated, 1.5G (GVW) scaping will present no structural damage but obviously the Cover will not look pretty...
I will be posting Additional Images as I Freeze TJOE designs for Rails/XMBRs, and bracketry over this weekend. Initial FEA Static Deformation Plots will be be uploaded early next week ... Followed by the TJ25 and TJ45 Design/Simultaion Packages.
I was thinking to have a Drawing/Static Simulation for the TJOE Steel Frame ready first ... however the increased effort to create the additional weldments convinced me to delay that effort ... most users are fully aware of how much flex they already have ....
The LJOE/LJ25/LJ40 design will start after upload of the TJ series
Full Disclosure: I have over the years accumulated a lot of specific acronyms ... and I admit to using them far too often ... I am lazy in that respect ... apologies ... pls call me out on my overly gratuitous use of them! .... r/
The JTOE/JT25/JT40 are complete frame assy as “mostly” imaged. The suspension geometry/Engine/Trans/Steering mounts will be predefined (as per drawing) and not modifable by the end user ... the intent is to be a “Bolt-on build”
For End-Users that wish the JTOE/JT25/JT40 to have other than the pre-specified geometry, Special adapters for all brackets will be installed lin lui of, to allow Machined Metal Fittings to be attached to the Composite Frame. This ensures that the Frame is allways receiving Forces/Moments in the correct locations up to the defined limits of the Frame/Brackets/Adapters.
The Lower Frame between Axles will have a User Replaceable Cover/Layer for Sliding/Scraping/Gouging ... 2-3G GVW “Loadings” onto single Frame Rails will be simulated and if required demonstrated, 1.5G (GVW) scaping will present no structural damage but obviously the Cover will not look pretty...
I will be posting Additional Images as I Freeze TJOE designs for Rails/XMBRs, and bracketry over this weekend. Initial FEA Static Deformation Plots will be be uploaded early next week ... Followed by the TJ25 and TJ45 Design/Simultaion Packages.
I was thinking to have a Drawing/Static Simulation for the TJOE Steel Frame ready first ... however the increased effort to create the additional weldments convinced me to delay that effort ... most users are fully aware of how much flex they already have ....
The LJOE/LJ25/LJ40 design will start after upload of the TJ series
Full Disclosure: I have over the years accumulated a lot of specific acronyms ... and I admit to using them far too often ... I am lazy in that respect ... apologies ... pls call me out on my overly gratuitous use of them! ....
r/
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UnrestrictedPilot
New Member
If this did go through, I suspect the best route is to go with a frame that supports a long arm suspension by a reputable company to ensure going to a fabrication shop to get the kits on doesn't have to happen anymore. However this will require many people to agree what is the best, overall company to use this on.
Personally I would want to see how the jeep handled over a year before I ever purchased a brand new frame. Its much more than just producing and selling it. The value needs to be shown correctly and that will require a lot of time driving, going to shows, etc...before a seed round can be put in place to get a lot of the frames sold. i.e. Your going to be sitting on your frame investment for over two years before money starts coming in to replace what was spent on development.
Personally I would want to see how the jeep handled over a year before I ever purchased a brand new frame. Its much more than just producing and selling it. The value needs to be shown correctly and that will require a lot of time driving, going to shows, etc...before a seed round can be put in place to get a lot of the frames sold. i.e. Your going to be sitting on your frame investment for over two years before money starts coming in to replace what was spent on development.
OP
I am currently reviewing the bushings used in various long arm kits ... a minority of the kits get resized (>OEM) Bushings/Pins ... accommodation of the larger rod ends (Baseline Brackets) for extreme modders should be straight forward, adding material (Bushing Retainer) for undersized Rods in the Baseline Brackets also straight forward.
The Test Progam (DEM/VAL) includes Material Characterization (partially complete), Critical Item (components), 4Post NVH, Abuse (200k cycles) and Durability (10 articles, 5Spectra, 50k miles), Cold and Hot/Wet will be done during the critical components and Material Characterization Test Programs.
Please note that the TJ/LJ applications are Technology Demonstrators, compliant with current Safety Requirements (FMVSS/NCAP).A business model cannot be made for the TJ/LJ as stand alone products. However a business model can be made for a Cross-Product application of the Design-Build technolgy demonstrated in this excercise ...
You are correct, this is not a Quick or Fast Program 18-24 months after Kick-Off will have the 10 Durability Test Articles ready for vehicle buildup. However Static/QStatic, Critical Component and Abuse Test Data will be available ... to interested entities ... 12-18 months later the 500k mile durability test data becomes available to fully validate the application ... and mitigate the cross-product appication concerns ... everyone needs to feel “warm and fuzzy”
to take risks ...
35y and 26 structural composite elements on every EC135 (>1300 flying Airframes) have resulted in 3 non-critical FAA SDRs .... I am a happy fellow! ...
OP
Ok after a reread of my last post ... I release I could have been less obtuse ... So ... here is the elevator version ... My product has and will always be “fit for use” Technical Data Packages (TDP). These TDPs are Build/Test/Manufacturing Guides (IP) to manufacture structural composite product that will conform to the Simulation Results contained in the TDP. I offer/sell and license the TDPs to Product Developers and sometimes Production Manufacturers that have demonstrated capability to follow instructions and conform to the Drawings/Build Process, or can convince me and others of their capability to do so ... I enjoy reviewing NCRs
So application investment on my part is high ... but after 35y I should have learned a few things ... my 2cents ....
So application investment on my part is high ... but after 35y I should have learned a few things ... my 2cents ....
So...to do list
#1 hit lottery
#2 Buy this here frame, LJ of course.
#3 mount one of those hand built aluminum bodies on it.
#4 LS and tons build
#5 Smiles for Miles! (while weighing in at...2700#s?!)
#1 hit lottery
#2 Buy this here frame, LJ of course.
#3 mount one of those hand built aluminum bodies on it.
#4 LS and tons build
#5 Smiles for Miles! (while weighing in at...2700#s?!)
OP
For those curious about an assembled JK Frame, especially the weight, I have attached a mass analysis I did some years ago ... 166kg/365# including structural detachables ... and still missing some pieces ...
... so I spent most of yesterday and today on the TJOE frame sizing for control rod attachment .... lots to choose from .. too many ... so I decided to max the Rod Frame Ends and thread the axle ends of the with 1-14 UNF and 1 1/4-12 UNF ... builders can then install fabbed Axle Bracket Ends or Rod Ends of their choice. The Frame End utilizes a modified/internally greased CE-9110P-xx. The “Standard” Control Rods therefore become part of the Frame ASSY and maintain frame loading.
The Extended TJ25/45/65 Control Rods (38”/24”) will be a similar concept, but come in Handed Upper/Lower Pairs with a single Frame-Side End.
So the “standard” adjustable control rods (CROD.445.405) become the first Part Numbers of this excercise ...
OP
Ya I am working on the cost ... it is not a matter of if I want to drop a point or 2 of margin ... the low rate of production, the constituent materials, the Tooling required to mould the parts, and the complexity limits/effort of manual labour vs robotic programming are what drive the cost of converting every kg of material into something fit for its intended use ... thankfully this is not my “first rodeo”
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OP
C-ROD.445.405 c0
Yea I know ... its green and it’s ugly ... but it does it’s job .... colour combo suggestions appreciated ... I’m an old fart and I am only guessing at what the younger generations find attractive ...
Weight is still hovering around 1.5kg with the Frame End Bearing ...
The C sized PDF drawing file will be uploaded later this week for those interested in that sort of thing .. need to add the C-Rods and their Mounting Brackets to the TJOE model
r/
Yea I know ... its green and it’s ugly ... but it does it’s job .... colour combo suggestions appreciated ... I’m an old fart and I am only guessing at what the younger generations find attractive ...
Weight is still hovering around 1.5kg with the Frame End Bearing ...
The C sized PDF drawing file will be uploaded later this week for those interested in that sort of thing .. need to add the C-Rods and their Mounting Brackets to the TJOE model
r/
OP
C-Rod Load Spectra and Load Case Derivations ... the Spectra is pretty typical for Safety and Robustnss, the Cases are my first shot at important Loads that can be used to determine/compare goodness between similar products with different materials ... other suggested Cases are welcome ...
OP
Ya I am working on the cost ... it is not a matter of if I want to drop a point or 2 of margin ... the low rate of production, the constituent materials, the Tooling required to mould the parts, and the complexity limits/effort of manual labour vs robotic programming are what drive the cost of converting every kg of material into something fit for its intended use ... thankfully this is not my “first rodeo”
I also should have added that, as having my own Bond Shop ... many moons ago ... a 20% Gross Margin for Manufacturers is something that I will always build in during the design ... efficient shops with minimal Non-Conformities deserve 20%! Average shops will struggle to survive on 20% ... so do I allow an inefficient shop to pass their shortcomings onto the end customer as a cost of mfg ... no! ... lower the NCRs and I will revisit them in 6 or 12 months ... one should note that even inefficient shops can have ISO certification ... but without a CARS (Corrective Action Reporting System) Formal or Informal and a responsive leadership ... continual 20% Margin will be be insufficient ... sad considering the quality improvement will mean a lower cost of mfg, and increased market competitiveness ... oh well ... on to “that which I can change”
As to. Composite control arms that's got even more issues with rock damage than the frame. (I like the frame slider thing by the way, I have no idea if 3G loading is enough or not. I can tell you I regularly see dents in 1/4 plate rock sliders or 1.75".120 wall Dom tube steps if it helps)
On my lower control arms I have massive gouges from sliding on rocks. They also regularly take massive impact loads from falling off rocks.
For long arm brackets have a look at TMR Customs 3 link and 4 link kits, something like that could probably be acomedated.
—
There must have been a time
when we could have said no.
On my lower control arms I have massive gouges from sliding on rocks. They also regularly take massive impact loads from falling off rocks.
For long arm brackets have a look at TMR Customs 3 link and 4 link kits, something like that could probably be acomedated.
—
There must have been a time
when we could have said no.
OP
So ... if ya want to bake a scratch cake ... you need to break some eggs ... right
After a week reviewing the various Rod Ends and “Strut” designs available for establishment of a performance “Baseline” ... I came across COR. Reasonable metallic designs and available data made it an easy decision to reference as structural baselines.
The correlation method I will use does not utilize the “as-installed” loads or paths. The simulations will correlate to a set of part-specific load paths as applied to a virtual “Test Fixture” that compares the deformation values of the Steel and Composite articles at their material limits (DSL, DLL, DUL).
The first article is the Front Track Rod/Strut ... ASTM A513 T5 1026DOM steel with published min Tensile Strength of 75ksi was used to iteratively determine the 3 moments (Axle) and 2 axial loads (Frame) required to reach material DUL. The DSL and DLL cells still need to be populated, but deformations at DUL are published. Once the remaining 10+ solves are completed, I will populate and republish this dwg with the first of 4 Composite Strut Profiles ... and their 5 Deformation Contour Plots (1 for each Case).
Of note ... the Steel Strut is working efficiently in Axial Loading ... however the Bending Moments at the Ends are fairly sensitive to “Bottoming” of the Articulated/Bushed Ends ... lots of potential strut plastic bending and fatigue issues in high angles of incidence ... my 2cents ...
After a week reviewing the various Rod Ends and “Strut” designs available for establishment of a performance “Baseline” ... I came across COR. Reasonable metallic designs and available data made it an easy decision to reference as structural baselines.
The correlation method I will use does not utilize the “as-installed” loads or paths. The simulations will correlate to a set of part-specific load paths as applied to a virtual “Test Fixture” that compares the deformation values of the Steel and Composite articles at their material limits (DSL, DLL, DUL).
The first article is the Front Track Rod/Strut ... ASTM A513 T5 1026DOM steel with published min Tensile Strength of 75ksi was used to iteratively determine the 3 moments (Axle) and 2 axial loads (Frame) required to reach material DUL. The DSL and DLL cells still need to be populated, but deformations at DUL are published. Once the remaining 10+ solves are completed, I will populate and republish this dwg with the first of 4 Composite Strut Profiles ... and their 5 Deformation Contour Plots (1 for each Case).
Of note ... the Steel Strut is working efficiently in Axial Loading ... however the Bending Moments at the Ends are fairly sensitive to “Bottoming” of the Articulated/Bushed Ends ... lots of potential strut plastic bending and fatigue issues in high angles of incidence ... my 2cents ...
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OP
So 3G static loading merely mean 3xGVW (3x1400-1700kg) ... balance the factored weight on 1 rail? or 2wheels? ... single wheel/Strut contact with a rock will require dynamic simulation due to the initial pulse followed by rotation of the vehicle mass. Planning on dropping more than 10m? ...
Now about the potential damage mechanism with rocks ... there are 2 issues involved ... a Kinetic Energy (KE) which is managed by the structure itself ... to a limit ... and an abrasive/scouring action which will definitely damage the structure ... so like ballistics ... one creates an outer selvidge layer which plastically deforms while protecting the substructure ... UHMWPE is perfect for this ... and is easily molded at reasonably thicknesses ...
4 Link Long Radius Rods are being looked at as a follow-on to the “short” Rods ... the issue is that if the frame is ordered with Short Rods ... an upgrade to Long Rods is not possible as the Frame Brackets for the Rods are not easily removed ... one of the downsides to structural bonding ... the Frame/Suspension will need to be mostly determined at order time. Perhaps “Dumb” solid models will be uploaded to On-Shape ...
Wow... It's hard enough to decide on a build plan, when you do have the flexibility to change mid build. I can't image a guy (like me) who is building a Wrangler for fun having enough foresight to know whether he wants long arms or short.
And if one were to want longer arms, where exactly should they go?