Need opinions. Hot rolled vs cold rolled???

[petawawarace]

I'm building a welding table / chassis table and I'm going to go with the 6" flat bar on top with 1" gaps between. I would love to use cold rolled,but not sure the 500+ extra dollars is worth it ($300 for HR or $850 for CR). I just want the top to be flat, I'm not going to get it ground or anything like that, just need it close. Has anyone built one of these with HR? If so how do you like it?

 

[BD1]

What size table ? How thick is the top material ?

 

[vtec?lol]

I used to work in manufacturing and we would get something called PO'd steel. It's hot rolled steel and then dipped in acid to remove mill scale and such. Then it's oiled to protect the finish from rust. To me it looks better than cold rolled steel.

Cold roll usually cracks with heavy heat/cool usage. maybe it was just ours.

For durability I would get hot roll especially for the price. If you want the looks, get it dipped.

 

[petawawarace]

Sorry it's going to be 1/2" thick top. Table is going to be a T shaped 4'x8'

I really don't care too much about looks, and I know I can clean the scale off of the HR

 

[dr_clyde]

It depends, mostly on how nice of a surface you want. I'm kind of suprised that there's that much of a price differential. Are you sure you didn't get quoted a different alloy? For that kind of money you could get a solid plate.

Anywho, if I was doing the slat table thing, I'd think cold rolled would be preferable, but not at that price. I'd shop around.

 

[dr_clyde]

If you can get picked and oiled HR, do it. You won't need the metallurgical benefits of CRS. Sometimes it's hard to find P&O steel in certain sizes.

 

[petawawarace]

I am waiting for a few more quotes back as I have a large order for other jobs as well. They are very competetive on aluminum, but perhaps not on the CR

 

[toddoky]

I just had a 48" x 48" x 1/2" plate quoted locally in both hot rolled and hot rolled P&O and the price difference was only 20 bucks (both were less than $240). It would cost you more than that for the electricity and consumable grinding/surfacing discs to produce the same result and you'll spend half a day doing it. Half a day of my time is worth far more than 20 bucks.

 

[kazlx]

If you aren't doing anything special, the layer on the HR actually resists the weld *************.

 

[RivennHewn]

If you aren't doing anything special, the layer on the HR actually resists the weld *************.

I've always wondered why people remove the mill scale on a work surface.

 

[Richard D]

Check out my table, 6"x5/8" hot rolled. I spaced mine 1 3/4" apart, you may consider that.
http://www.garagejournal.com/forum/showthread.php?t=225206

 

[pepi]

Sorry it's going to be 1/2" thick top. Table is going to be a T shaped 4'x8'

I really don't care too much about looks, and I know I can clean the scale off of the HR

The scale actually helps keep the splatter from sticking, if welding a lot on the table could be something to ponder.

 

[chattacuda]

I made mine of 3/8 hot rolled. The mill scale actually protects the table. The few places on it where I had to grind off welded on jigs rust so easily and the rest looks as good as it did when I built it. I considered 1/2", but the 3/8" is more than enough for my needs. I would not use cold rolled.

 

[Xtremetalworks2]

We have made several fabrication tables similar to what Richard D's table looks like but we use C-Channel instead of flat bar I think the channel was 4" and we spaced them about 4inches apart gives less flat surface to work off of but gives you the benefit of clamping to the edge of the channel for vertical pcs. Guess alot depends on the type of fab work your doing !

 

[Xtremetalworks2]

Added note the C part is standing up just like the letter C

 

[muibubbles]

Added note the C part is standing up just like the letter C

Pics?

 

[Kevin54]

If you don't plan on having the table top blanchard ground, go for cold rolled steel. It is way flatter than hot rolled. In making dies and fixtures, I had to use hot rolled on occasion and in doing so I would maybe cut a piece 12" x 12" and the hot rolled would be out of flat by maybe .050 or more. A piece of Cold Rolled, maybe out .010. Huge difference between the two.

 

[Xtremetalworks2]

If you don't plan on having the table top blanchard ground, go for cold rolled steel. It is way flatter than hot rolled. In making dies and fixtures, I had to use hot rolled on occasion and in doing so I would maybe cut a piece 12" x 12" and the hot rolled would be out of flat by maybe .050 or more. A piece of Cold Rolled, maybe out .010. Huge difference between the two.

Big problem alot of people make though Kevin is have blachard ground then weld it to a frame which kind of defeats the precision blanchard ground. Have also worked with guys that will bolt a blanchard ground to a twisted frame rather then shim up and then bolt.

 

[Kevin54]

Big problem alot of people make though Kevin is have blachard ground then weld it to a frame which kind of defeats the precision blanchard ground. Have also worked with guys that will bolt a blanchard ground to a twisted frame rather then shim up and then bolt.

Very true. A perfectly flat piece of metal is only as good as what it's fastened to.