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Old 02-11-2013, 05:08 AM
  #346  
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Originally Posted by InspGadgt
He is making his own shocks and springs
Okay, I didn't know that. They look very similar to the Losi Micro-T shocks. I'm using those for side springs and dampers on my F1, and they work pretty well.

Originally Posted by protc3
That is correct. Losi springs are way too soft. Borderline pen springs.
Yes, I've been cutting the springs to get a higher spring rate, but they're still pretty soft! If your springs will fit the Losi shocks, then they woud be perfect for my application. Can you tell us the ID and length? If your shocks are aluminum, they would make an excellent upgrade, too!
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Old 02-11-2013, 06:05 AM
  #347  
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Actually, for the front shocks, they are the losi shocks. I am making spring to fit that are stiffer. Sorry if I mislead anyone. The losi shocks work extremely well.
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Old 02-11-2013, 06:21 AM
  #348  
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Hey J,

Car looks great cant wait to see one in person.
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Old 02-11-2013, 09:31 AM
  #349  
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Originally Posted by protc3
The one i was referring to is a panhard type 4 link suspension.
Like the Schumacher Supastox?
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Old 02-11-2013, 09:45 AM
  #350  
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Jason, I've been looking at this suspension quite a bit and I absolutely dig what's going on here. But I have some questions / ideas.

For Camber gain, the short/long arm options I see on the aluminum bulkhead - how do those compare with something like the CRC or associated short and "long" options for upper arms as far as distance from the hub. Hard to get an idea of scale in these pics.

Also caster - is caster going to be handled via hubs (C Hubs?)? Since the single pivot ball inboard mount wont allow for specific caster adjustments. Also having some additional inboard mount points for the screw (fore and aft) will give the ability to keep the upper arm aligned with the hub if you do have different angled hubs for caster changes.

After doing some testing I found how important even minor changes in caster can be.

Durability is something that I am curious about (as you stated as well), you able to incorporate fore/aft brace bars to link the bulkheads so in a hard hit you don't need to worry about tweaking those? I know Delrin is strong and has some flex to it, so the aluminum bits are what I am worried about the most. One wear area I am looking at is the area that the arm goes into the delrin lever for the shock, I am wondering how much play will develop there over time.

Excellent work man!
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Old 02-11-2013, 11:13 AM
  #351  
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Originally Posted by protc3
This week I am going to try to make the steering blocks, C hubs and steering spindles. That will be it for the front end, Then it is on to the pod. I cant wait to try this thing out.
Think you could use AE R5 trailing Spindles and Inline Spindles? Might reduce costs and it would be nice to have the inline option for the WGT car eventually.
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Old 02-11-2013, 01:49 PM
  #352  
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Originally Posted by AdrianM
Think you could use AE R5 trailing Spindles and Inline Spindles? Might reduce costs and it would be nice to have the inline option for the WGT car eventually.
It is going to be inline. The trailing spindle is used to tone down the strut front ends as they are crazy aggressive with it having drastic roll center change throughout its suspension travel. The steering geometry I have is going to need new spindles made so I need to make them in order for the geometry to be correct.
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Old 02-11-2013, 02:11 PM
  #353  
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Originally Posted by Clegg
Jason, I've been looking at this suspension quite a bit and I absolutely dig what's going on here. But I have some questions / ideas.

For Camber gain, the short/long arm options I see on the aluminum bulkhead - how do those compare with something like the CRC or associated short and "long" options for upper arms as far as distance from the hub. Hard to get an idea of scale in these pics.

Also caster - is caster going to be handled via hubs (C Hubs?)? Since the single pivot ball inboard mount wont allow for specific caster adjustments. Also having some additional inboard mount points for the screw (fore and aft) will give the ability to keep the upper arm aligned with the hub if you do have different angled hubs for caster changes.

After doing some testing I found how important even minor changes in caster can be.

Durability is something that I am curious about (as you stated as well), you able to incorporate fore/aft brace bars to link the bulkheads so in a hard hit you don't need to worry about tweaking those? I know Delrin is strong and has some flex to it, so the aluminum bits are what I am worried about the most. One wear area I am looking at is the area that the arm goes into the delrin lever for the shock, I am wondering how much play will develop there over time.

Excellent work man!
The length of the arm on a double wishbone as opposed to a strut are quite different as far as handling goes. Mine are shorter than a long arm CRC or AE. You need them to be. You are working with 2 pivoting arms and camber gain is different.The camber gain on a double wishbone is increased when you have a shorter length upper arm than lower arm. It also increases with just short pivot points. It is less touchy of an adjustment on a double wishbone than on a strut. It is not nearly as abrupt.

You want less camber gain on a strut to tone it down. As your suspension compresses on a strut, 2 things happen, you get camber gain and also roll center change. As the kingpins angle relative to the upper arm changes, your roll center changes. Going to a longer arm will minimize this. That is why everyone is going to long arm on the strut. Double wishbone, you dont need to do that.
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Old 02-11-2013, 02:15 PM
  #354  
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I forgot to answer the question about for and aft turnbuckle adjustment on the arm mount for the turnbuckle. There isnt going to be and for and aft movement. As of now I am looking to make 2,4,and 6 degree hubs. The angle of the spindle will change in the hub as I am making the cutout in the hub at an angle and not the hub itself. This will keep the pivot ball location the same on all 3 C hubs. I hope that makes sense.
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Old 02-11-2013, 02:28 PM
  #355  
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Originally Posted by Conrad
Like the Schumacher Supastox?
exactly
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Old 02-11-2013, 02:54 PM
  #356  
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Originally Posted by protc3
The one i was referring to is a panhard type 4 link suspension.
Darn, I was trying to envision a Watts link on a 1/12..

-B
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Old 02-12-2013, 02:27 AM
  #357  
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To be honest, that would protrude down past the bottom of the chassis if i tried to keep the pivot point where i have it now. I also want the pod to tilt as it compresses to free the car up through the corner. If the pod stays flat during compression, it generates too much rear traction and makes it hard for the car to rotate. I will see how everything goes during testing. If rear traction becomes an issue, i will look into some sort of 4 link setup if it is needed.

It is cool being able to share the build and progress of the car with you guys.

Last edited by protc3; 02-12-2013 at 02:53 AM.
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Old 02-12-2013, 10:25 AM
  #358  
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Originally Posted by protc3
exactly
Thanks for the clarification . It does work really well on the supastox but as it runs on the same width of tires front and rear I can see why you need that style of setup for extra side bite as you've already mentioned. The GT12 class is becoming really popular in the UK just now.
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Old 02-12-2013, 02:14 PM
  #359  
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Yeah, that setup might work well for outdoors on a dusty track with a pan car. Its just not that much of a call for it. Most want to free the car up.
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Old 02-12-2013, 03:32 PM
  #360  
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Originally Posted by howardcano
Okay, I didn't know that. They look very similar to the Losi Micro-T shocks. I'm using those for side springs and dampers on my F1, and they work pretty well.



Yes, I've been cutting the springs to get a higher spring rate, but they're still pretty soft! If your springs will fit the Losi shocks, then they woud be perfect for my application. Can you tell us the ID and length? If your shocks are aluminum, they would make an excellent upgrade, too!
Cutting a spring does not increase its rate!! (retired Mechanical engineer that applied springs)
When a spring is wound it's rate is fixed and is based on the wire diameter, winding diameter and the space between coils. Shortening a spring only does just that other than reduce the dimension at which coil bind happens.
Another myth that r/c racers employ. Cranking down the collar to make it stiffer. This is only increasing preload and changing the ride height, it does not make the spring stiffer!!
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