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Discussion Starter #1
I've been working on designing and building a bumper for my truck since last summer. I started doing all of the design work on CAD software. In February I finally had something I like and made a mock-up out of cardboard. I made a few changes to the design and sent all of the drawings off to a buddy to get cut out for me. I got the pieces back last weekend and started welding. So far I have tacked my center section together, both sides of the bumper, and got my mounts fabbed up. Next weekend I hope to get the center section mounted on the truck, then I should just need to finish welding. I really only have time on my weekends and the shop I have access to right now is only open till 4:30 on Saturdays so its taking longer than I would like to get everything finished. Here are some pics of the process and the build so far.

Cardboard Mock-up:


Revised CAD Image:


Center Section:


Passenger Side:


Driver Side:


Mount:


Everything built and either on or in front of the truck:


I created a separate photobucket album to keep track of my build. There are a bunch more pics there. Bumper pictures by Bear9350 - Photobucket
 

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holy balls that's incredibly nice fab work man.
 

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Discussion Starter #3
Fea

I am also working on a FEA analysis of the bumper. I am currently a Mechanical engineering senior and was able to work this analysis into a school project. I will be looking at the stresses and deflection in the bumper, mounts, and frame in several impact type situations. I want to design the bumper and mounting system so the weak spot is an easily replaceable strap in the mounting system. I don't want this strap to give when in an animal type crash, am aiming to make it yield shortly after to avoid frame bending issues. This is just an initial test on my system while troubleshooting the model:

 

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I bet you could sell those, they are beautiful. What does the green mean on your analysis? And the little speck of red?
 

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Discussion Starter #6
I bet you could sell those, they are beautiful. What does the green mean on your analysis? And the little speck of red?
I am thinking I might try and sell them. I am trying to go for a bumper that isn't that much larger than the stock bumper (it doesn't stick out a foot in front of the truck) and flow well with the lines of the truck.

The green area in the analysis is the amount of stress in the area. There is a legend in the corner of the pic relating the color to the stress level. That image is an analysis of 170 psi applied to the plate seen as mostly green. That is a very rough estimate of what would happen if you hit a 200 lb deer going 55 mph. I am actually setting up a simulation with the bumper and frame assembly and a separate part representing a an animal. I can give the "truck assy" a velocity and simulate it hitting the deer at different speeds and different positions on the bumper.

The red dot is just the where my cursor was when I captured the image.
 

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Confidence Antler
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The green is the locale of stress. He's using Von Mises to figure stress in his FEA which is for yield strength in ductile materials. The blue is non stressed areas and the green is stressed (looks like he was simulating an animal impact), but it is below yield strength. The red looks like it could be a failure but being a tiny point like that it is negligible and due to a simulation error (in the program, not his error). Bear what CAD program are you using? SolidWorks?
 

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Discussion Starter #10
would that be able to fit a winch behind it ?
I don't know. I didn't design it with an intent to be able to place a winch behind it. I had to put a lot of thought into how I wanted to design the mounting system because of the limited amount of room between the frame and bumper. There is a little more room in the center of the truck though. I will have to take some measurements when I get everything mounted to determine how much room is back there.
 

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Discussion Starter #11 (Edited)
The green is the locale of stress. He's using Von Mises to figure stress in his FEA which is for yield strength in ductile materials. The blue is non stressed areas and the green is stressed (looks like he was simulating an animal impact), but it is below yield strength. The red looks like it could be a failure but being a tiny point like that it is negligible and due to a simulation error (in the program, not his error). Bear what CAD program are you using? SolidWorks?
I used Pro-E to do all of my CAD work. I was able to get it installed on my computer. I am using HyperMesh to import the models and mesh them and Abaqus to run the FEA. The red dot is just the node I had selected when I took the screen shot. I am actually sitting here waiting for an analysis to run right now. Only 10 days into the month and I all ready listened to 38 hours of Pandora, all running analysis and troubleshooting for the FEA.
 

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Confidence Antler
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The red dot is just the node I had selected when I took the screen shot.
Oh yeah that would be the obvious explanation :rofl

I had SolidWorks with the Weldments (among others) add in on my comp, and was in the process of designing a bumper and then the stupid thing crashed on me and the new educational addition of SW doesn't come with Weldments. I really don't want to spend any more time in lab than I have to, I'm sure youu know how that goes :rof

So you have your weakest point set as your mounting strap? That's a good idea, have you clearanced the bumper so when if it fails it won't shove into your cooling stack?
 

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Slave to the Interwebs
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That looks nice man. I want to do something simular to mine
 

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Confidence Antler
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Only 10 days into the month and I all ready listened to 38 hours of Pandora, all running analysis and troubleshooting for the FEA.
If you have a smart phone listen to Pandora on that, no time limit :rockin

Hey at least you aren't rendering also! (well, yet :rof )

Once spent 5 hours running a single render on an adjustable kickstand we designed, gotta love school computers :rolleyes:
 

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Discussion Starter #15
Oh yeah that would be the obvious explanation :rofl

I had SolidWorks with the Weldments (among others) add in on my comp, and was in the process of designing a bumper and then the stupid thing crashed on me and the new educational addition of SW doesn't come with Weldments. I really don't want to spend any more time in lab than I have to, I'm sure youu know how that goes :rof

So you have your weakest point set as your mounting strap? That's a good idea, have you clearanced the bumper so when if it fails it won't shove into your cooling stack?
Not yet. Once I actually get everything mounted on the truck I will be able to see where everything actually is in relation to the truck. Its hard to get good measurements to build one of these things with just CAD. Nothing is straight and there is never a good place to measure from.
Once it is on I will be somehow limiting the amount of deformation in the mount to make sure the bumper doesn't cause damage to anything when it moves.
 

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Discussion Starter #16
If you have a smart phone listen to Pandora on that, no time limit :rockin

Hey at least you aren't rendering also! (well, yet :rof )

Once spent 5 hours running a single render on an adjustable kickstand we designed, gotta love school computers :rolleyes:

Every time I log in a get a message saying I am over my limit for space. I am currently working on a CAD project and this FEA project. I have deleted everything else from my profile but I am still over our allowed limit.

When I run out of time on Pandora I can just switch over to my slacker account. No limit there either.
 

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Confidence Antler
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Not yet. Once I actually get everything mounted on the truck I will be able to see where everything actually is in relation to the truck. Its hard to get good measurements to build one of these things with just CAD. Nothing is straight and there is never a good place to measure from.
Once it is on I will be somehow limiting the amount of deformation in the mount to make sure the bumper doesn't cause damage to anything when it moves.
I know exactly what you mean :rolleyes:

Seems like a sweet build so far man! Keep up the good work!
 

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nice work! make me one for my truck. i would like a heavy bumper but not a fat lip on my truck.
 

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Discussion Starter #20
nice work! make me one for my truck. i would like a heavy bumper but not a fat lip on my truck.
If I can find access to a NBS truck I am hoping to design a bumper for it. Aiming for a similar style as this one.
 
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