PrInSu Design Studio Roof Racks BS Thread

I'm the same way with my RTT. It's a PITA for one person to do it, not to mention if you even tap my truck its damn alarm goes off. So I don't worry about it, more people ask me wtf it is

 

I'm looking at getting that viper remote start/alarm system it's got a two foot invisible fence around the vehicle to warn people to back away then if you touch it it goes off and your key fob reaches a mile and it will tell you on your key fob if the alarm goes off

 

Hey Zach sent you a pm.

 

If I were to order one of these in raw aluminum and paint it myself,(to save some$) what paint would you guys recommend. I know that powder coating is more durable, but its not like the thing is going to rust if the paint wears off over time. Just trying to weigh my options. I'm 99% sure I'm going to order one by the end of the week, just trying to decide it I want to paint it or have it painted.

 

Best thing to do is to scuff it up with a scotch pad and then use an aluminum specific primer. From there, I really like the rustoleum professional spray can stuff. It holds up well. Prep is everything though with these racks cause the aluminum is smooth and if you just try to go straight with paint it will come off quickly.

I personally am a fan of powdercoating anymore. I got tired of touching up painted items so I try to Powdercoat anything I can.

 

Agreed, if it isn't a wear item like sliders or bash plates then off to the powder coater it goes.

 

Any updates on the wind noise issues previously discussed in that video or design changes? The option of "turning the music up" isn't going to work for me as this is a DD and family vehicle too.

 

Has anyone mounted a toprac on a Raider Vagabond?

 

There wont be any design changes. Without being able to replicate wind noise on my own rack I can't make changes to eliminate it. I am using the edge trim with all new racks which seems to help but otherwise the only time I get wind noise is on days that it is really windy. Like this morning we had 60-70 mph gusts and I could hear it whistling through the rack while I was running errands. Yesterday though, there was nothing.

I did think at one point that having more crossbars eliminated noise but I am back down to 6 bars and havent noticed a difference.

 

Have you thought about reaching out to a local college who might be able to assist in reducing the noise? I'm not an expert in it obviously, so I'm not even sure where to start (other than the Physics dept). You do have a great looking design though.

 

Dude, you're putting something on the top of truck... It's gonna mess up the stock aerodynamics no matter what. I don't think anyone can expect no wind noise with any type of rack.

 

I'm aware of that and would definitely expect some noise, yes. I think Zach is doing what he can, and he's doing a good job trying to replicate the problem.

 

I agree with you Zach. There is some noise that is expected when you are changing the aerodynamics of the roof line when installing a rack. I've had my rack on almost a year now. With or without gear on the rack,not really any noticeable changes in noise levels. I also put the edge seal on the deflector plate and it made no noticeable changes in noise either. I rode in other people's trucks that have OEM racks on, and they have about the same noise level. Wind noise changes as well depending on what you place on top of the rack. If you place certain items close together, they can cause a whistling affect that will drive you crazy. SO of course you're fixing that right away. I have my windows down, going 70 MPH on the freeway and can still hear a normal conversation inside the cab. I've never joined any conversations here about noise bc I've really never had a problem with loud noises coming from my roof rack, except the occasional crosswinds on the freeway. You have to get acustomed to the increase of noise once you installed a roof rack. You are modifying your rig, expect some noise changes.

 

This is a good idea. The biggest problem I see is there are just so many variables. I am about 99% sure that the majority of the noise that people complain of comes from specific directional winds. I have had my rack on the roof for over 2 years now in various configurations and violent head and side winds are the only times that the noise is noticeable.

 

Do you have any 3d model of the current version of the rack? I have a moderate amount of flow simulation and aerodynamics experience through mechanical engineering and access to the student version of Solidworks Simulation. I could take a look to see if there's anything glaring that could be tweaked. (After the GB of course,a little too late to be changing the design haha)

Edit: I do have an idea adapted from a friend who worked for Rocky Mounts last summer. It's definitely not proprietary, and it could be added to existing racks

 

A 3D model of the rack is easy its the vehicle 3D model that I don't have. I would imagine that most of the turbulence occurs due to the windstream coming off the front and side of the vehicle so simulating it would require an accurate model of the truck as well.

 

I finished installing my Toprac on my tonneau cover. Thanks Zach for all your help. Zach's customer service is 2nd to none. I'm really pleased with how it turned out.

 

Thanks for the quick reply, I went ahead and ordered it with the sides and wind deflector powder coated, figured it'd be better to have it done professionally. Can't wait to get this thing on my truck.

 

(Not trying to nag, just throwing some thoughts out, don't let me slow you from manufacturing racks )

You're right in connecting the turbulence of the rack (or any fluid flow system) to noise, as they're directly proportional. I don't have a rack currently (soon hopefully) but it sounds like people are attributing most of the noise to the front portion (possibly because it is right over the driver's head). But from what I can tell by looking at it, your design is very aerodynamically similar to wind deflectors on baskets and whatnot from other big companies (Thule, Yakima).

One thing that isn't really addressed is fluid turbulence around the aluminum extrusion crossbars. They're not inherently aerodynamic, and are designed for static use (framing etc). Without being able to purchase aluminum extrusions in the shape of an air foil (which is what Thule uses), the best bet is to improve what is already in place.

I think the "T" slots really throw a wrench into the fluid dynamics of the rack as a whole. My bet is that the slots create a small clockwise turbulent flow, that could easily be corrected by filling it. 6 bars x 2 slots each side x 2 sides x 47 inches per slot means theres 94 feet of less than aerodynamic slots on the racks. My first thought was laying tape, but that'd leave a nasty residue if removed. But then the idea came to me about using rubber extrusion similar to the quick drawing below to plug the channels. Air would flow around the bar while creating less turbulence. The strips could be cut to length around points where bolts are thrown into the channels.

Not saying this is an undertaking you need to address yourself (@zscott ) as you're already busy enough, but for anyone who would like the rack a little quieter keep this in mind. The rubber could even be made a little thicker/wider and it would result in a grippier surface on the top of the rack.