Why aren't there aluminum radius arms? (1 Viewer)

[Delta VS]

before this site were refreshed, there is a thread talking about the radius arms.
deltavs who is a vendor in here did say about something, he need the actual radius arm in order to make a pair.
i was on the list, but i couldnt take off mine yet. you can email @Delta VS

You're talking about the 70 series arms?

 

[Tsvigo]

You're talking about the 70 series arms?

yeah , i was about to send mine to you for sample,suddenly all my parts came in . i couldnt take it off yet.

 

[mudgudgeon]

I think I'm going to make two sets, one for me and one for a friend

Do you need a friend?


Sounds like it could be a cool product.

If you can demonstrate its strength and durability is no less than steel, cost is similar, and you can provide good customer service and meet demand with timely delivery, go for it, there's probably no reason it won't succeed.

The weight saving is somewhat appealing even if it's debatable whether it's advantageous

 

[cody c]

Interesting comments in this thread, making arms sounds so simple.

Did anyone price out a 4x8 1.5” thick sheet of 7075 yet to easily fab up a bunch of arms yet? I think that’s where the plan will end.

As for type 3 anodizing protecting the arms when being dragged over rocks, that sounds like a fairytale to me. If I remember correctly, 7075 doesn’t take coatings as easily as say 6061 either.

Also, not sure if there is any truth to it, but someone said they thought radius arms maybe be heat treated more similarly to spring steel to handle forces better. Not sure on that though.

But, if you want to do it, certainly do, it may work well, proof is in the pudding! However, a three link kit with existing brackets and some new ones pre fabricated seems more attractive for the dollar to me, and helps with caster issues better and at different lift heights.

 

[mudgudgeon]

3 link is not without it's downsides either.
Not everyone wants to go to all the trouble of welding in a not so easily reversed three link to fix caster, and introduce a bunch of other issues in the process

 

[landtank]

Do you need a friend?


Sounds like it could be a cool product.

If you can demonstrate its strength and durability is no less than steel, cost is similar, and you can provide good customer service and meet demand with timely delivery, go for it, there's probably no reason it won't succeed.

The weight saving is somewhat appealing even if it's debatable whether it's advantageous

doing a carbon copy of the stock arm is pretty simple, but who is going to buy that?

The real prize would be an arm that also corrects for caster and doesn't induce drive line vibrations.

For that you need a keen sense of geometry and drive line dynamics.

 

[PIP]

Did anyone price out a 4x8 1.5” thick sheet of 7075 yet to easily fab up a bunch of arms yet? I think that’s where the plan will end.

As for type 3 anodizing protecting the arms when being dragged over rocks, that sounds like a fairytale to me. If I remember correctly, 7075 doesn’t take coatings as easily as say 6061 either.

Also, not sure if there is any truth to it, but someone said they thought radius arms maybe be heat treated more similarly to spring steel to handle forces better. Not sure on that though.

Yes, maybe you missed it, but I stated at least twice in this thread that 7075 is not that expensive when you buy aluminum in bulk. Or maybe expensive is just relative? I don't buy thick aluminum plate by the sheet, I just buy it sawed to the sizes I specify. If I buy a whole sheets worth or not it doesn't really matter. The cost to saw a large plate up is not anything much.

7075 is more complex to anodize than 6061 because of how the alloying elements effect the solution. I do not know exactly what this entails with a 7075 part this large so that is a concern I will be discussing with my anodizer. I know that type 3 has significant current requirements when you get into larger part sizes and that requires really solid connections in racking so the current can pass into the part effectively. When I bring a sample arm to the anodizer I will discuss options and will propose I make titanium inserts that fit one of the bushing bores for racking purposes. They will know better than I and I will follow their recommendations.

The stock radius arms are forged from mild steel. I could speculate they were something like 1018 or 1020 steel, but it doesn't really matter. The description of "mild steel" nails it down as steel that doesn't have any spectacular qualities that would respond to heat treating. The factory arms are forged and trimmed followed by shot blasting, then they are fixtured in a large HMC where the bushing bores are bored and chamfered. Somewhere in there they are painted/coated. Probably before machining. That's it. No magic, just some big forging presses with dedicated tooling do most of the work.

 

[use2bn83]

If I had free time and an open mill, I’d be running down a robust and clean mechanical CDL. I’ve spent too much time chasing down wiring, replacing connectors, and contemplating pulling the trigger on $1k actuator.

Side note, 7075 type III anodizes well, usually a deep gray. It will not hold up to rocks scraping it. It’s very very wear resistant when abrasion is distributed over a large area or up against softer materials. However, it fractures easily because it’s so hard and the surface it’s covering is so soft relatively speaking. Think of an M&M. The surface that don’t make rock contact should hold up great.

 

[PIP]

doing a carbon copy of the stock arm is pretty simple, but who is going to buy that?

The real prize would be an arm that also corrects for caster and doesn't induce drive line vibrations.

For that you need a keen sense of geometry and drive line dynamics.

Reading through the troves of conversations about castor VS lift is almost information overload. My take away so far is for your typical 3" lift there is a very small window of castor where you can have good handling and no vibes with a standard front driveline. I am not a big fan of double cardan joints and would prefer NOT to utilize one on my own 80. Finding that sweet spot is what the development stage will be centered around. Machining the arms is very basic stuff.

 

[PIP]

Oh yea... if you’re rocking a mill made somewhat recently, I would interpolate the holes and call it a day. The bushings are very forgiving, and TOP is not terribly important here (with respect to the general accuracy of a modern mill vs the application ).

I just saw this bit you added while reading back through the thread again. Kind of gaging interest/collecting ideas.

I do have a couple nice CNC mills that would interpolate the bores well. My reasoning for boring them would be to use a fixture with expanding bosses to hold the arms on the second op. If the bores are dead nuts every time they will fit the fixture perfect every time. Fixturing off the bores helps to "self check" the parts. If something is wrong in the first op then it won't fit the fixture on the flip and it gets fixed before bad parts are made (important with expensive materials). I use this tactic with a few different part families I make and it seems to work well.

 

[FMC80]

I like your approach and desire to do something. I agree that competition is a good thing and more products out there for us is also a good thing.

Lots of different perspectives on this topic in particular and of course some naysayers have cropped to the surface. I consider those people like my mom, she ain’t happy unless she’s bitching and I can almost ignore her after all these years.

Ahem anyway, what’s the timeline look like?

 

[Dusten]

I like your approach and desire to do something. I agree that competition is a good thing and more products out there for us is also a good thing.

Lots of different perspectives on this topic in particular and of course some naysayers have cropped to the surface. I consider those people like my mom, she ain’t happy unless she’s bitching and I can almost ignore her after all these years.

Ahem anyway, what’s the timeline look like?

I think a lot of the naysayers are looking at this from the perspective of a business that's not setup to make these.
This guy clearly already has facilities and access to everything.

 

[FMC80]

I think a lot of the naysayers are looking at this from the perspective of a business that's not setup to make these.
This guy clearly already has facilities and access to everything.

You think so? I wouldn’t assume the guy is just some dude off the street with aspirations to make aluminum radius arms for the 80 but didn’t have the desire, capability, and opportunity. Either way, I support.

 

[Dusten]

You think so? I wouldn’t assume the guy is just some dude off the street with aspirations to make aluminum radius arms for the 80 but didn’t have the desire, capability, and opportunity. Either way, I support.

I do.
While you and I may not assume, a lot of the comments suggest otherwise

 

[PIP]

I don't want to set a timeline for a radius arm product. Lots of things to do before we are at that point. I will likely be making the first arms in February, but I'm not rushing into it. I like steady progress. I'm going to do lots of 80 series castor measuring right now, then design and build a fixture to machine them. Once we see some results then we can start talking about the product aspect.

Having the right machines and skills to make these helps, but it boils down to putting in the work to get it there.