Bumper/air tank

[KY Chris]

Hey, I know that some of you guys have built bumper/airtanks. What is the best way to prep/clean the inside of the bumper after welding?

[robs]

Doh! You're suppose to prep them!!! =)

Actually... I didn't do boo... just made 'em thick... and gave it a drain...

[JJ13]

If you are concerned with rust and what-not getting in your air supply, Eastwood has a product that is made for restoring the inside of fuel tanks that works great. You pour it in and rotate the tank around so the liquid covers everything on the inside and it cures to "seal" the inside. May not be a bad idea, especially if you aren't going to filter your air on the way out.



http://www.eastwoodco.com/department.asp?dep_key1=spc&SKW=FSPEC

[KY Chris]

Ok...here's somemore questions. I am using 11gauge 3x3 box. Should I be concerned with the safety of this as a tank? I am confident in my welds and the thickness of the steel, but are there other issues? I already have my Sanden compressor changed over from AC and I have run it for about three years now with an old scuba tank, so I will have a pressure switch and safety valve in place. The tank will not fill over ~130 psi, tops. I have figured I can get almost 7 gallons out of the bumper so it will be a slight improvement over the scuba tank. Any tips?

[JJ13]

Even if the bumper failed it would probably just make some noise for a few seconds.

[Beezil]

don't worry about "prep"....

just do a fine job welding and you'll be good.

I find its easier to do an endcap that slides into the tube, so you can do a fillet weld in the 90-degree corners, rather than trying to seal the tank with an endcap that goes over the outside of the tube. you can always put a "decorative" endcap over the ends afterward.

[2xtreme]

Originally posted by KY Chris
Ok... I am using 11gauge 3x3 box. I have figured I can get almost 7 gallons out of the bumper

I am in the process of designing my front bumper/air tank also. i just made a mock up out of wood and was going to use 3/16 3x6 box tube. My caluclations estimate I can get very close to 4 gal out of it. I would re-check your 7 gal estimate.

Michael

[KY Chris]

The bumper is 3x3 box, 9 feet long + another 5 foot section underneath. My rear quarters are cut, so the bumper is mitered and actually wraps around like a U. Beneath this 3x3 is another section of 3x3 that is 5 feet long. It's hard to explain, I'll have to take a picture, anyhow, it's roughly 14 feet of 3x3 which is 6.54 gallons.

Chris

[KY Chris]

Ahhhh, it took me a couple of reads to get what you were saying with the end caps. That makes sense.

Originally posted by Beezil
don't worry about "prep"....

just do a fine job welding and you'll be good.

I find its easier to do an endcap that slides into the tube, so you can do a fillet weld in the 90-degree corners, rather than trying to seal the tank with an endcap that goes over the outside of the tube. you can always put a "decorative" endcap over the ends afterward.

[Rufies97XJ]

Can I see some pictures of these bumpers... new to XJ scene... very interested in learning what you guys are doing...would be interested in making drawings on CAD if anyone wants them.

[2xtreme]

Originally posted by KY Chris
The bumper is 3x3 box, 9 feet long + another 5 foot section underneath. My rear quarters are cut, so the bumper is mitered and actually wraps around like a U. Beneath this 3x3 is another section of 3x3 that is 5 feet long. It's hard to explain, I'll have to take a picture, anyhow, it's roughly 14 feet of 3x3 which is 6.54 gallons.

Chris

I see how you get that estimate. I did not realize there was an extra 5ft under neath. I am doing my front first. and will be building the rear afterwards. I would be very interested in pic's of yours (particually mounting and such). I was going to build the rear out of 3x6 also but still not sure, my quarters are cut also so it will continue around the front also. Are you supporting the ends (right behind the wheels) to the frame or not??

Thanks,
Michael