Fabrication questions

[dzzz]

1) Anyone see oval steel tube used for bullbar and other armor? I believe I have, but I can't find a pic or a source for the raw pipe.

2) Will I regret smooth painted under bed boxes (as opposed to chromed diamond plate). Is there any advantage to a particular material or finish?

3) Anyone have a source of synthetic material to replace oak between frame and subframe? Any suggestions for quiet metal to metal contact in the frames?

 

[chasespeed]

The oval stuff, is lightweight, like exhaust tubing...

Under bed boxes.... Hmm... tough one... I say an aluminum box, will last a HELLUVA lot longer in that case, than steel ones.... just use steel to mount it, and protect them. A lot of stuff being tossed around under there, and painted steel basically gets sand blasted, and will rust pretty fast.....

The bed.... Hmmm, I think oak really is your best bet, but, there is always Trex... expensive, heavy, and not very strong. But, its synthetic.

Chase

 

[FlatlinesUp]

1. oval looks cool and has good properties when used in the correct alignment for the application, however, it's kinda a pita to work with as you can't bend/form it easily without distortion, nor can you cut angles in it and weld it and have the ellipsis line up without gaps (or a LOT of engineering)

2. diamond plate offers the thickness of the diamond, with only a slightly heavier weight of the flat thickness that the diamond rests on (make any sense?) ie sliding over something leaves you sliding on the diamonds, not the flat under them

3. can you use simple HDPE? cheap and available, or use Delrin/acetal which is also very strong (45k+ psi compression) self lubricating, and pretty much element proof. You can find chunks of either as cutoffs on ebay etc

 

[jeepdreamer]

1) Anyone see oval steel tube used for bullbar and other armor? I believe I have, but I can't find a pic or a source for the raw pipe.
This stuff is usually pretty thin walled. Depending on what you were making you could find some prob. pretty cheap. Its used a lot on factory "Nerf bars" and is usually being given away. Also some Futons and odd furniture can be found made with it. No idea where it comes from as I"ve never seen it in any of the places I buy my new steel. Scrap meatal yard or junkyard would be a source if you don't mind recycling?

2) Will I regret smooth painted under bed boxes (as opposed to chromed diamond plate). Is there any advantage to a particular material or finish?
-I would find the best quality for the least price. Steel ones will usually be less expensive. Yes the paint will go away fast so...Scuff them up, coat them with heavy Rustoleum enamel primer, let fully cure, then hit it with spray on bed liner in a can inside and out! Done deal.

3) Anyone have a source of synthetic material to replace oak between frame and subframe? Any suggestions for quiet metal to metal contact in the frames?

What is the application for this oak? 1/2 ton vintage truck or some kind of comercial 5500 type jobbie? They use oak for it resistance to compression in the big trucks. Imagine a piece of pine or whitewood doing the same job!?!:Wow1: If you are just replacing some missing/worn/ or rotton chuncks, try locating some oak pallets behind your local HD/Lowes (ask first) many of these are made of oak for just the same reason. ANd it should be free.
Or, barring that you could try some of the more exotic woods like Ipe. Its from Brazil and is growing in popularity in the states due to its hardness (like Balistic grade...stuff is spooky hard!) and its inherent resistance to rot and bugs. Should be cheaper than oak (new oak) and able to be special ordered (if not on hand) at a real lumber yard.I doubt you will find any synthetic that will perform the same. Not to say it doesn't exist...I just have never heard of it. All the Man-made decking products are far to "soft'' for anything structural.
What kind of metal to metal contact? Can you offer a pic or discription? How much area, what kind of shape, etc...It may be as simple as applying some antisieze every now and again or you may have to think outside the box? Stuff like skateboard rails, tails, and nose parts are pretty good for making a friction reducer...?
Hope this helps?

 

[dzzz]

It's an Alsakan camper and secondary platform on a Unimog.

The Alaskan frame has solid attachment only at the rear, so the camper frame can separate momentarily from the truck frame. The body builder says the oak will last about ten years. He orders exactly the size he needs from a local saw mill.

I will have a couple bolt-on pieces. A crane in the front, and non-folding stairs in the rear. I'm wondering how to keep those types of items from rattling. The builders does nice, complex work truck. With those a big clank when going over a bump is normal. I want no clank.

 

[jeepdreamer]

hmm...

Its past bedtime here in the sandbox so I will think about it and try and get back in the am, ok?
Though first idea without thought is airbags...?

 

[R_Lefebvre]

I've seen aerofoil shaped tubing for aircraft and race car parts, but it's very light gauge. I've never seen oval available anywhere, though I'm sure a manufacturer could do a custom mill order.

 

[ntsqd]

Only consistent place that I've seen oval tube used is in 'Winston' Cup car exhausts. Can buy bends etc., but it's not structural.

I'd choose an acetal ("Delrin" etc.) over HDPE based on the potential for cold flow. There is also a material known as "Jobrock" (sp?) that is highly abrasion resistant and it might work well in this application.

If you do use aluminum boxes be aware of the galvanic corrosion potential where it is bolted to steel and take steps to eliminate it.

I do not see any gain in using diamond plate for anything except step treads (foot traction is it's reason for being) and perhaps panels where you do want 'desert pinstriping' to be obvious. Most are not chrome plated, but rather an acid generated bright finish that is then clear-coated in some manner. Once the clear is penetrated water will get under the clear. Then the finish slowly goes to hell and short of striping the clear, polishing, and re-coating there is no way to fix the appearance. If you are worried about rock chips look into 3M "Helicopter tape." It is used on the leading edges of carbon fibre helicopter rotor blades to keep airborne grit from damaging them.

 

[dzzz]

I do have a deck area behind the cab where I will need to use stainless or aluminum. I would like to use stainless checker tread plate if I can find in and afford it. An alternative would be a sheet of stainless or aluminum painted with bed protector.
As far as the finish on the boxes, I'm drawn to regular paint as it's so much easier to renew than powdercoat. I could do bed liner on the underside
I like this product, which capt'n Eddie says is treadplate: