: fabing a rear bumper, a few ?
jpenrose 08-08-2006, 11:10 PM I'm making a rear bumper for my rrc that is pretty simple, 3x4 with the 4 inches facing back. Tapered to 2.5 inches at the outside to 2.5x2.5 tube forward to rear tire.
I'm cutting the frame horns that the stock bumper mount to, at vertical, and welding a 4"x1/4" plate across the two frame rails. My idea is to bolt the bumper to the plate, using 4 bolts spread evenly between the frame rails, which are 31" outside to outside. I'm adding some simple support tubes from the frame to the bumper portion just behind the tires. Keeping the stock trailer receiver, I tow regularly
It will take a 4.5" bolt to bolt from the outside of the bumper through the plate. Is this too long to bear the weight of the vehicle that will occasionally be draggin its arse up rocks. I am thinking 0.5" grade 8 bolts. Should I sleeve the bolt holes through the bumper?
Should I feel comfortable with drilling the holes through the bumpers with a floor standing drill press, and a long bit. Going to tack weld the mounting plate to the back of the bumper for drilling and welding nuts on the backside then remove and install on truck. Or does anybody have a "tool" like the drill centering guide that rovertym provided with their rock slider that would work on the 3" square tube?
Back to the hitch receiver, I have always used a Dring block in the receiver, so I wasn't going to put on any Dring tabs on the bumper for recovery. I would like to put something on to hook safety chains to though (and would look cooler, but cost more money and have to be mail ordered) or should I just make some chain inserts in the bumper, the kind that look kinda like skeleton key holes (kinda flatbed truck look).
PTSchram 08-09-2006, 06:37 AM Build it the way you see fit and see what you end up with. Bumpers are one of the hose things where nobody but you is gonna like everything about it and everyone will say they could do better, but never do.
Definitely sleeve it if you don't want it to collapse.
As for the drill guide, make one or see what ENCO might have to offer, but I doubt you'll find an affordable off-the-shelf drill guide 4" long.
Build it and post pics so we can all copy yours!
PT
revor 08-09-2006, 10:10 AM For a drill guide in place, drill a hole in a thick piece (1/2"+)of steel, tack weld it to the spot you want to drill and go to it, once you are done knock it off and smooth it up.. You should pilot with a small hole in this fashion then open it up without the block to the final size.. We do this on some of our equipment when we can't fit a Mag base drill.
Like PT said Sleeve it..
The "skeleton" chain notches are generally desiged to be used with a chain in tension, this might be a problem with loose safety chains..
I like the design though... Sounds like what I am doing, bent up the steel last weekend, now if I can ever get around to welding it up!!!
cptyarderho 08-09-2006, 10:21 AM the factory hitch setup is really strong, no need to reinvent the wheel unless you want to be creative. Bumpers are like assholes, oh wait- wrong idea. If it covers what you want, then do it. Many tie into the area just behind the rear tires to protect that area but you can always just cut away the metal there.
cptyarderho 08-09-2006, 10:24 AM Rovertym made this one for me since I am sans welder- but you can see how the bumper offers some side protection.
jpenrose 08-09-2006, 11:24 AM Okay, i will go back and pick up some sleeving material, makes since, even with 3/16".
as for safety chain key holes, thanks keith, i could see the chains yanking right through
yeah, I don't expect everybody to like it, hell, I hope i like it!
I may be cheating by using box tubing but it makes it a lot quicker, I don't have access to a break and the time/money to make a big metal table to booty fab some sort of bender or take sheet in and have it cut and bent and then come home and weld it all together.
Yes the factory hitch is really strong, thats why I am keeping it. But, if you tow regularly then I highly recommend checking the weld onthe top of the hitch regularly, where its welded to the rear crossmember, mine was cracked and for how long who knows but with some of the loads I pull it would have sucked if everything let go, second one I have seen like that.
Agreed on the sleeving. That's what I did when I built new frame horns for my RRC. Also, the metal in the frame at the back of the truck is really thin. Be careful when welding on it that you don't constantly blow holes in it from too much heat!
Regarding the bolt, here is a good doc to read. I think you'll be fine, expecially since you won't ve towing or doing any recovery from the bumper.
http://www.pirate4x4.com/tech/billavista/NutsandBolts/Nuts&Bolts_signed.pdf
However, I would not put the safety chains on the bumper if it were me though. If the hitch fails and the safety chains are needed that could potentially be a whole lot of sudden stress that your bumper won't likely be designed for. But that's just me.
Oh, and this thread is worthless without pics!! :flipoff2:
Junkyddog11 08-10-2006, 05:01 AM just seeing if I've finally figured out how to send fawkin' pictures.......it is at least a bumper on an RRC:flipoff2:
just seeing if I've finally figured out how to send fawkin' pictures.......it is at least a bumper on an RRC:flipoff2:
That's pretty slick looking. Great departure angle!
BeachBum 08-10-2006, 11:03 PM LWG I have your old one, I bought it from Paul Reyes a couple of years ago. Still working out well. Can't figure out how to post it though.
Later, Paul
Junkyddog11 08-11-2006, 04:00 AM That's pretty slick looking. Great departure angle!
It's better with the exhaust run out through the bumper (as on my shop heap) but this fella didn't want to run a new system. That's OK though 'cause he'll tear it off soon enough....hehehe.:D
Nomar 08-11-2006, 06:04 AM Junkyddog, can you show a pic of leading edge/fenderwell area?
jpenrose 08-11-2006, 08:27 AM I spent some time improving my design lastnight, after seeing junkyd's junk i figured I could make it look a little better with minimal material and time.
Ready to do some cutting today and hopefully welding up this weekend or early next week. I will have some pics and specifics (measurements) if anyone is interested next week.
Larry, what do you have on the rear now? I was going to review your design but I can't...
What kind of shop would have a CNC sheet metal bender, if this bumper thing turns out decent I may tackle some sliders but I don't want to use two pieces of angle iron to connect to the sill. So I need to find someone who can bend some sheet up for me. I used a sheetmetal shop to make some stainless steel backsplashes for someone, I will start there but I am afraid to know how much they will want for four bends, they mostly do creative signage and display work for the casinos and restaurants.
LWG I have your old one, I bought it from Paul Reyes a couple of years ago. Still working out well. Can't figure out how to post it though.
Later, Paul
Send me the pics and I'll post em for you. I have some pics of it from years ago I could post. That is one heavy ass bumper though!
Larry, what do you have on the rear now? I was going to review your design but I can't...
Here's some pics of my latest bumper.
http://pics.montypics.com/lwg/2006-03-26/1143424201_dsc00543__medium_.jpg
http://pics.montypics.com/lwg/2006-03-26/1143424216_dsc00544__medium_.jpg
What kind of shop would have a CNC sheet metal bender, if this bumper thing turns out decent I may tackle some sliders but I don't want to use two pieces of angle iron to connect to the sill. So I need to find someone who can bend some sheet up for me. I used a sheetmetal shop to make some stainless steel backsplashes for someone, I will start there but I am afraid to know how much they will want for four bends, they mostly do creative signage and display work for the casinos and restaurants.
While the arguement can be made that a CNC bent piece will be stronger, I don't think it really matters for this application. It would costs quite a bit more than just welding up 3 pieces of plate and calling it good. Plus you'll never see it down there.
ProsQtor 08-11-2006, 08:54 PM Larry, how did you route your exhaust? I don't see it anywhere in those pictures. Did you cut it off short?
UPOVR 08-11-2006, 09:55 PM look directly under OU badge on the tailgate and below the bumper.
Junkyddog11 08-12-2006, 04:49 AM Junkyddog, can you show a pic of leading edge/fenderwell area?
Similar bumper. The other one has gone away with the owner.
look directly under OU badge on the tailgate and below the bumper.
Boomer Sooner! Good eye.
ProsQtor 08-13-2006, 05:13 PM look directly under OU badge on the tailgate and below the bumper.
Ahhhh.....nice. :grinpimp:
| |