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Finished design of front suspension Rx7 FC to 323 sub-frame

So I threw out the original design as I didn't like a few aspects of it, mainly being that it was overly complicated, not as flexible with the position of the steering rack to the Lower Control Arms(LCA) and not as strong. To address some of these design flaws i re-designed it around some 25X50X2.5 rectangular stock I had in the shed. I also changed the design of the brackets for the power steering rack to make them easier to position providing more flexibility during construction. I've made the height of both the the LCA's and the steering rack adjustable by 60mm in three 20mm increments. The I've sent the parts of to the laser cutters to be cut in 3mm mild steel with all the files available here . Once they are back I'll mig weld them together as I don't posses a TIG welder at this time. New Sub-Frame Design Old Sub-Frame Design I built the old design in cardboard after printing it on paper sticking it to the cardboard and cutting it out. This...

Suspension Design Solid works

To assist with integrating the Mazda RX7 S4 FC front suspension into my Mazda 323, I've decided to see if I can create a solid works model for the suspension and then one for the Mazda chassis to see what fabrication work is need to integrate it. Looking online into engineering tutorials I found a site called Grab CAD community and a tutorial on there around spring design in solid works which looks fairly strait forward. https://grabcad.com/tutorials/tutorial-how-to-model-a-suspension-spring-in-solidworks-and-show-design-intent The main issue I have is the Lower Control Arms (LCA's) are a rather complex shape and will require me to up-skill in SolidWorks to be able to reproduce them. I'm in the process of sandblasting the part and taking some better images from which to model it. *UPDATE -- 1FEB17 nearly finished sketching the LCA and spindles

Mazda_323

Mazda_323 The above link is for a suspension model I measured from the stock Mazda 323 suspension and setup in  the model creating tool at Racing ASP to assist in mapping the stock Roll Center and predicting the new roll center with the RX7 FC Suspension.

Adapting FC front suspension to a 323

Having come across a Mazda FC shell cheap that still had a majority of the suspension components less the struts, I've decided to embark on swapping the whole front sub-frame over. This means creating new guards as the old ones won't cater for the increase in the track width and either adapting the sub-frame to suit the 323 chassis or vise-versa, which ever is the easiest. To accommodate the track width of the  FC will require several modifications: the center of the strut tops to be moved outward by 38.5mm The Frame rails need to be moved outward by 57.5mm Here's the comparison: Mazda 323 FA4US Vs FC Dimensions Vehicle 323 Mazda - FC Wheelbase 2,311 mm (91.0 in) 2,431 mm (95.7 in) K ingpin Inclination 8.3 deg 13.45 Length 3,820 mm (150.4 in) 1986-88: 4,290 mm (168.9 in) Width 1,595 mm (62.8 in) 1,689 mm (66.5 in) Curb weight 812 kg (1,790 lb) 1,223–1,413 kg (2,696–3,115 lb) Wheel size 175/70R13 205/55R16 ...

New Work Bench

Recently I brought myself a BOSS MIG-186 some disposable Ar75%/CO25% for mild steel and Strait Ar Gas for Stainless. I've welded up a small movable welding bench with some 10mm plate for the table top. I wanted to make some more bench space so I've designed and fabricated a bench to go along the side-wall of the shed to marry up with the existing stainless bench and incorporate a sink. Eventually the plan is to put some cupboard doors on this to keep things looking a bit neater under the bench. It's made of 40mm Square tube with a 2mm wall thickness and utilising two struts(orange) from some pallet racking for the under bench support, allowing for a 2600mm span. The steel was $160 the pallet racking pieces and sink where free.

Bigger Brakes III

I spent some time in Solid Works designing a sheath to go over the existing Spindles as they are tapered and only have a maximum diameter of 20.5mm and the RX7 FD brakes require 33mm. Standard 323 Spindle: Solid Works Drawings for Spindle sheath Next will be to design some brackets to go mount the new brake calipers to the existing location. The backspace between the strut and the new disc brakes should only be around 6mm more than std due to the thickness of the disc centre where it fits over the new Hub.

Bigger Brakes II

After getting the std brakes off the car it is obvious that the std spindle is going to be way to small being 17.4mm at the front and 25mm at the rear with two flat sections and a taper in between. The std FD HUB is a uniform 32.5mm so a sleeve will need to be made up to fit over the 323 spindle. To this end I've been working in Solid Works to CAD up a design for the sleeve. I will use an M33 3mm thread on the end to secure it and will be TIG welded to the standard Spindle.