Amazon: Brake System Upgrade

[Colonel Froth]

The method of using the ball joint in that picture isn't ideal unless you have reason to be confident you can adjust for maximum positive camber without the thread being at risk of bending. The camber adjustment on the standard mounting point is pretty good.

[dheming]

The stock camber adjustment scheme is indeed much stronger mechanically. My goal is to get away from having to use shims. What I'm thinking at this point is making some tubular A-arms similar to these ones. Strong, adjustable and simple.

[rrktmn]

The pictured A-arm is sold by Canley Classics UK and used on Herold based suspensions( Spitfire, Lotus7 etc). I have had them installed on my Triumph GT6 for several years without incident. It's just another approach to ease of adjustment.

[Colonel Froth]

Yes if you often need to quickly alter camber and you can be confident that the thread size is large enough to deal with the loads generated by the vehicle then the Herald design is useful. If the exposed threaded section is checked regularly for corrosion and fatigue the risk of catastrophic failure can be minimised.

The second design doesn't involve applying massive bending moments to a threaded bar which is a wee bit mechanically safer. The only advantage the second design has over a solid wishbone using shims is that caster can be adjusted and you don't have to open the bonnet to adjust camber. If you have to make a large negative camber adjustment the camber gain and probably the roll centre end up being better with a shimmed wishbone.

[Bartezz]

Happy new year all!

I'm def following this thread. Wish I had the tools and knowledge to do this to my 122s! Envy envy!

Cheers from the Netherlands!

[Bartezz]

Here's some threads from my favorites which you might not have seen;

Andrew's 122 project
http://forums.turbobricks.com/showthread.php?t=266523

KA-T Powered 1967 Volvo 122s
http://www.ka-t.org/forums/viewtopic...b6f865ee2a98ce

1965 Volvo 122 Project "Old Balls"
http://www.stanceworks.com/forums/sh...ad.php?t=22268

Adjusted control arms for Honda coilovers use
http://forums.swedespeed.com/showthr...=1#post2017351

MikeJr's 1967 122 Project (Cupped control arms and 4 link rear)
http://forums.swedespeed.com/showthr...67-122-Project

Project Canuck - 1966 Canadian Build Thread ... Finally
http://www.calgaryvolvoclub.com/foru...php?f=1&t=2227

Mostly pics on lowered Amazons
http://www.turbobricks.com/forums/sh...d.php?t=266490

Added bonus Sickest Amazon build I've seen (Google translate helps), Murres 69a
http://amazon.forum.bilia.se/phpbb3/...hp?f=18&t=6927

[dheming]

Thanks for all those links Bartezz. That last one with the build by Murres is the thread I was referring to earlier about the front coilover mod. I will have to sit down sometime this weekend and methodically go through every one looking for ideas and inspiration.

[dheming]

None of the steel suppliers around here carry 4130 chrome-moly. Apparently it's too specialty for them to bother. So I've been searching for a single online supplier that carries tube as well as flat stock and plate. Ordering one thing from three different suppliers starts to add up in shipping. Turns out Aircraft Spruce has a nice variety of 4130 steel and they also have reasonable shipping rates: http://www.aircraftspruce.com/catego.../me/steel.html

I just ordered some 0.25" x 1.25" (6.35mm x 31.75mm) flat stock and a small 9" x 9" x 3/16" (22.86cm x 4.83mm) piece of plate so I can finish the upper coilover bar. Time to get this show on the road.

[dheming]

Small update. The 4130 chrome-moly plate showed up late last week:





Over the weekend I made the brackets that will be bolting to the frame rails. Since 4130 is tough on blades I decided to use my shop mate's plasma cutter instead. I have almost no experience using a plasma and in hindsight I should have made the wood template a little larger to avoid the gouging that happened with my unsteady hand:







Here you can see the various small gouges on the bottom curve and the big slip on the bottom right corner. Being a perfectionist I'm deciding what I want to do about these:





Sitting in position on the right side frame rail:





As for the actual design of the upper coilover bar itself I've changed it a bit from the last design (Mk3.3) shown back in post #136. Decided to make it simpler in that the two cross tubes will now just be welded directly to the brackets instead of bolting to the brackets, basically making it all one piece now. This necessitates careful fitup of the tubes and tack welding it all together with it in position between the frame rails. Here's a quick mockup of this new Mk4 design:

[dheming]

Been doing a lot of research on what filler rod to use for 4130. There's quite a lot on info on the net about welding this alloy. Bottom line is that it depends on the thickness of the material and if the part will be heat treated afterwards or not. For my application I decided on using Oxweld 32 rod.

When it comes to welding new metals I always like to do a few tester pieces first before jumping into making parts from it. Some metals like copper and Inconel are difficult to weld so it pays to practice a bit on scrap to learn how the puddle forms and flows. With that in mind I cut a small piece from the tube:





I had some scrap plate left over from making the frame rail brackets. From that I cut out a shape that might be used as a bracket of some sort:





With 4130 that's over 0.12" (3mm) thickness a preheat of about 400° is recommended. I don't have any of those fancy temperature crayons yet so I just winged it with the MAPP torch for this simple tester piece. I always have trouble welding around small diameter tube like this. It's difficult to follow the small radius with the torch at the proper angle so the beads end up looking inconsistent, often with some undercutting as well.





The other thing I wanted to check with making this part is if the plate would warp at all. Looks like the preheat completely prevented that. After welding this thing measured just as flat as before. Slowly moving forward on this multi-year long build project.