RPM Steering and Suspension

[Crawl2Camp]

3 hours ago, fiend said:

Ugh. Looks like that smittybilt crap. I never liked that look but it’s a matter of personal preference.  Like the grumpers 

Yeah I wasn't much of a fan of it myself, but I just wanted to pass it along.
I can see doing rear corner armor once they get beat, otherwise I want to keep all that extra weight off my Jeep. 

[Jetlau3]

On 2/24/2023 at 10:43 PM, Crawl2Camp said:

Fender delete armor. 

I’ve always liked the side and rear quarter armor . The front fender look is horrendous . 

[Gruff]

On 2/25/2023 at 1:43 AM, Crawl2Camp said:

Fender delete armor. 

 

 

Seems he's taking all the stuff he did for Rde2rok's jeep years ago and decided to market it. I practically begged him t make me the high steer setup he did for him but he quit returning calls & emails. Shame. All his stuff looks nice

[Crawl2Camp]

On 2/25/2023 at 10:11 AM, AJK said:

Good plan you got, what thickness arms you going with?

 

Yeah I'll hit up Don when the time comes. I dont like to bug people unless I plan to buy or in the process of buying. This wont happen till after June at least.

 

Also, I really like what Brian has for the front and rear mount to go with RPM rear.

I went with 2.25” diameter links for the front that I ordered.

Yeah I was always apprehensive and a bit shy to reach out and talk to people.  After almost two years stuck on basically bed rest, I’ve learned I can only find and learn so much on the interwebz, and most people are excited and willing to tell you about their products etc..   

Brian has some really nice products, I definitely agree.  I really like his rear triangulated 4 link brackets as well as his rear coilover tower. Unfortunately the last time I was talking to him, I was focusing on keeping the stock gas tank.  We ended up talking about his high clearance and rear 3 link and not his triangulated rear. 

 

[Crawl2Camp]

14 hours ago, Gruff said:

 

 

Seems he's taking all the stuff he did for Rde2rok's jeep years ago and decided to market it. I practically begged him t make me the high steer setup he did for him but he quit returning calls & emails. Shame. All his stuff looks nice

I know he did some work on Rde2rok’s Jeep, but I don't know much back story to be honest.  Don did talk to me about him a little the last time we talked, but it was more about coilovers and the challenges to run the longer lengths up front.  

Yeah, I did read your post/response on Eddie’s website about the custom steering you wanted, him eventually ghosting you and your eternal love for aluminum links etc..   That’s a bummer as I’ve had a few similar experience with other companies.  At least here we can all leave honest feedback. 

Well I guess I will see how things go on this front 3 link.  I’ve had nothing but good interactions with him so far and he’s even called me on evenings and weekends to answer questions etc..  

 

[Gruff]

4 hours ago, Crawl2Camp said:

I know he did some work on Rde2rok’s Jeep, but I don't know much back story to be honest.  Don did talk to me about him a little the last time we talked, but it was more about coilovers and the challenges to run the longer lengths up front.  

Yeah, I did read your post/response on Eddie’s website about the custom steering you wanted, him eventually ghosting you and your eternal love for aluminum links etc..   That’s a bummer as I’ve had a few similar experience with other companies.  At least here we can all leave honest feedback. 

Well I guess I will see how things go on this front 3 link.  I’ve had nothing but good interactions with him so far and he’s even called me on evenings and weekends to answer questions etc..  

 

 

Don and the rde2rok (I forget his name) seem to be pretty tight. And they both seem like good guys. His build thread over on the other site is pretty good. I think RPM may have been going by something different at that time. Maybe not - Its been quite a few years. But I've always loved that setup. His Jeep may be a little tall but man it sure works. 

 

I'm sure this will work out for you. Looking forward to seeing pics. 

[AJK]

7 hours ago, Gruff said:

 

Don and the rde2rok (I forget his name) seem to be pretty tight. And they both seem like good guys. His build thread over on the other site is pretty good. I think RPM may have been going by something different at that time. Maybe not - Its been quite a few years. But I've always loved that setup. His Jeep may be a little tall but man it sure works. 

 

I'm sure this will work out for you. Looking forward to seeing pics. 

Yeah meet him out at KOH last year. Nice guy and really nice rig in person.

[AJK]

Ok so considering I bent my evo lower control arm ever so slightly, how does the aluminum arms stand in strength comparison. 

[Gruff]

The idea of the 7075 is that it will flex but return to it's original shape. Two reasons why I went with DOM: I bent two 7075 tie rods. Good ones made by Bubba. And they get gouged really easy. 

 

You can weld so no reason why you can't make your own DOM arms up. 

[Weebz]

I went with aluminum.  I also have two bent Evo long arms sitting here as paper weights now.  By the time I factored in making DOM or buying, the price delta wasn’t enough for me to not go aluminum.  My experience with aluminum is rather different than Jerry’s.  I’ve held my rig up on my tie rod many times and it has always rebounded perfectly.   Weight savings, longevity in my experience, and overall maintenance (granted they don’t look as nice now but better than painting them constantly).  

[AJK]

 

4 hours ago, Gruff said:

The idea of the 7075 is that it will flex but return to it's original shape. Two reasons why I went with DOM: I bent two 7075 tie rods. Good ones made by Bubba. And they get gouged really easy. 

 

You can weld so no reason why you can't make your own DOM arms up. 

I dident even think to make my own and you're right , it would be easy.

3 hours ago, Weebz said:

I went with aluminum.  I also have two bent Evo long arms sitting here as paper weights now.  By the time I factored in making DOM or buying, the price delta wasn’t enough for me to not go aluminum.  My experience with aluminum is rather different than Jerry’s.  I’ve held my rig up on my tie rod many times and it has always rebounded perfectly.   Weight savings, longevity in my experience, and overall maintenance (granted they don’t look as nice now but better than painting them constantly).  

 Ping Pong, I love it.

[Gruff]

4 hours ago, AJK said:

 

Ping Pong, I love it.

 

Jeff wears pink sweaters, so.....

[Gruff]

7 hours ago, Weebz said:

My experience with aluminum is rather different than Jerry’s.  I’ve held my rig up on my tie rod many times and it has always rebounded perfectly.   Weight savings, longevity in my experience, and overall maintenance (granted they don’t look as nice now but better than painting them constantly).  

 

I concede the TR's from Bubba are not as big in dia as the Fusion/Rare Parts ones we're running now. More than likely why I bent 2 

[AJK]

43 minutes ago, Gruff said:

 

Jeff wears pink sweaters, so.....

LMFAO....hahahahahaba

[Weebz]

45 minutes ago, Gruff said:

 

Jeff wears pink sweaters, so.....

How rude.  It’s Salmon!!!!

[Crawl2Camp]

17 hours ago, AJK said:

Ok so considering I bent my evo lower control arm ever so slightly, how does the aluminum arms stand in strength comparison. 

Alan what kind of answer are you looking for?  

Do you want me to get technical or are you just looking for an opinion?  I can do either, my paper on the wall is in Materials Science and I've got 25 years experience in aerospace materials testing and quality control.  I’ve specifically worked a TON with 7050 alloy among others over the years (very similar to 7075), as it’s what makes up a majority of the structural aluminum in modern aircraft besides a few 2000 series alloys.  

 I honestly have no idea what Evo makes their arms out of (1010, 1026 or 4130 chromoly?), or if they even do any normalizing treatment after welding to remove welding stresses.  All of those things are important.  

And yes, I’ve also had the front of my jeep fully supported by my 1.75” 7075 tie rod on multiple occasions with zero deformation.  Unfortunately I bent my steel unit that I got with my axles from ECGS the first shakedown run I did.  I’ve already ordered a 2” 7075 bar to replace it.

 

[Crawl2Camp]

8 hours ago, Weebz said:

I went with aluminum.  I also have two bent Evo long arms sitting here as paper weights now.  By the time I factored in making DOM or buying, the price delta wasn’t enough for me to not go aluminum.  My experience with aluminum is rather different than Jerry’s.  I’ve held my rig up on my tie rod many times and it has always rebounded perfectly.   Weight savings, longevity in my experience, and overall maintenance (granted they don’t look as nice now but better than painting them constantly).  

Sorry, I quoted the wrong post.  

[AJK]

46 minutes ago, Crawl2Camp said:

Alan what kind of answer are you looking for?  

Do you want me to get technical or are you just looking for an opinion?  I can do either, my paper on the wall is in Materials Science and I've got 25 years experience in aerospace materials testing and quality control.  I’ve specifically worked a TON with 7050 alloy among others over the years (very similar to 7075), as it’s what makes up a majority of the structural aluminum in modern aircraft besides a few 2000 series alloys.  

 I honestly have no idea what Evo makes their arms out of (1010, 1026 or 4130 chromoly?), or if they even do any normalizing treatment after welding to remove welding stresses.  All of those things are important.  

And yes, I’ve also had the front of my jeep fully supported by my 1.75” 7075 tie rod on multiple occasions with zero deformation.  Unfortunately I bent my steel unit that I got with my axles from ECGS the first shakedown run I did.  I’ve already ordered a 2” 7075 bar to replace it.

 

Technical answer. Evos are made of 1.75' OD x .313 Wall DOM tubing is what I am finding, and honestly never though I would damage these. It just a slight bend enought you can see if I point it out. 

[Crawl2Camp]

1 minute ago, AJK said:

Technical answer. Evos are made of 1.75' OD x .313 Wall DOM tubing is what I am finding, and honestly never though I would damage these. It just a slight bend enought you can see if I point it out. 

Yeah I checked EVO’s website last night also to see if they list the actual material details etc..  They don't list the grade of the tube that they use.  DOM just represents the manufacturing process the tube went through when it was manufactured.  It was “drown over a mandrel” to have better dimensional control, basically eliminate the weld seam and increase strength (more on the surface) from the cold work performed during the drawing process.  I’ll assume it’s either 1010 or 1020, but let me dig into that a little.  The aluminum is easy, I already have all that data. (7075 bar in the T6 temper)


 

[Crawl2Camp]

OK Alan here is the comparison. I used 1026 grade DOM as both Synergy and Icon state that grade is used by them in their links.
Just look at the yield strengths and that tells you what you want to know.  
73 KSI for 7075
45 KSI for 1026

 

 

 

[Crawl2Camp]

Here is an example of a tensile test stress strain diagram so you can better understand why the yield and more importantly the elastic limit behind the yield (the strait line where the material can return to its original form without deformation) is important. Been trying to pull this all off the net, as all of my reference books are in my office at work. 

[Gruff]

Ok, but where's all the data from the scratchy tests? 

 

 

[Jdofmemi]

On 2/27/2023 at 7:32 PM, AJK said:

Ok so considering I bent my evo lower control arm ever so slightly, how does the aluminum arms stand in strength comparison. 

I went with aluminum arms for the White Jeep, and built my own DOM arms for Vengeance. 

 

If you go aluminum, make sure it is 7075, not 6061, and make sure it is thick enough to hold up. 

 

If you go DOM, you can buy the steel local, and get the weld in bungs for the rod ends. I got mine from GenRight. 

 

I have the tap, both RH and LH thread, in case welding them in causes any issues. 

 

The DIY version is cheaper and easy to build to whatever length you need.

 

My uppers are 1.75" diameter 0.120 wall.

The lowers are 2" diameter 0.250 wall. 

This gives both a 1.50" ID, which is what the weld in bungs are made for. 

 

Uppers only see tension and compression load, unless something is way wrong. They don't need to be as strong. 

 

Lowers see that loading, as well as impact loading when you hit things with them. 

 

I started this this morning, then work got in the way of finishing, so there is more added above already. 

 

I am actually surprised that you found the EVO arms to be 0.313. 

It is an odd size, and seems like more than needed. 

I did not cut a lower arm, but did cut one of the uppers to use the front piece. It was 1.5" OD, as it slipped into the DOM I used, and it wasn't any thicker than the 0.120 wall tube I was using. 

 

Picture is of the cut off pieces from the upper and lower links I built. 

 

[Crawl2Camp]

4 hours ago, Gruff said:

Ok, but where's all the data from the scratchy tests? 

 

 

Scratchy tests?  LOL
Rubbing it down with a 3M pad every once in a while works pretty well I’ve found. I used the heavy maroon pad followed by the fine grey (going with machine marks) and it came out great in just a minute of work.  

I also use Tef-Gel on any aluminum to steel connection like this (and my beadlock bolts etc) to prevent galvanic corrosion due to the dissimilar metals of the aluminum center bar and the steel ends. 

https://www.ultratef-gel.com/tef-gel/


 

[Crawl2Camp]

You guys that want to use steel, why not go to 4130? That’s a lot stronger than 1026 DOM and you can run a much thinner tube (less weight) and have higher strengths.  Best of both worlds, but you’re going to pay for it .   I’ve seen more than one company making custom chromoly links for people.