Is malleable cast iron on for clamps?

[Stephen White]

OK building up inventory of pipe clamps.

These are specifically for gluing up cutting boards but will be using for other projects as well including furniture. I am using Bessey 3/4 pipe clamps and went to Lowes last night and got some pipes for four of them and they were $16 bucks a piece for threaded 3 footers. I went to order another set of 4 Bessey clamps and found a set of 4 36" black malleable cast iron pipes for $10 ea. I know malleable cast iron is not as strong as galvanized but never worked with it b4, anyone have these kind of pipes for their clamps? Would love saving a few bucks but if it bends then would just be a waste of money.

Been on the lookout forever for some good used pipe clamps but no one seems to ever sell them

[Tom Trees]

The only thing that would make a difference in strength is the gauge or wall thickness of the pipe,
galvanised is just a hot dipped coating of zinc, its does not mean its any sort of alloy.

I presume all those pipe lengths would be produced from regular mild steel, and not cast iron, so would do a check to see if its legit.
Although pipe fittings might well be cast, I'm not going to pretend I know anything about that,
but it might explain the title.

Tom

[Mel Fulks]

The black is ,I think, is the usual shop preferrence. The galvanized tend to slip a little more .

[Rich Engelhardt]

I know malleable cast iron is not as strong as galvanized but never worked with it b4, anyone have these kind of pipes for their clamps? Would love saving a few bucks but if it bends then would just be a waste of money.

You had me running for Google with that & from what I could find, the black is actually the stronger because it's made without a seam. (according to what I read).

Either way, I use black - mainly ecause of what the others are saying about slippage.

[glenn bradley]

To maximize my buying dollars I bought 10' sticks of 3/4" pipe at the BORG and had them cut at about 60:40. They threaded the ends for free. People talk about galvanized pipe slipping but, I have been using the same pipe for nearly 20 years and never had an issue. Pick up a few 3/4" couplers to have on hand for hooking pipes together. I keep mine on a piece of wire that hangs from the pipe clamp rack.

[Stephen White]

The only thing that would make a difference in strength is the gauge or wall thickness of the pipe,
galvanized is just a hot dipped coating of zinc, its does not mean its any sort of alloy.

I presume all those pipe lengths would be produced from regular mild steel, and not cast iron, so would do a check to see if its legit.
Although pipe fittings might well be cast, I'm not going to pretend I know anything about that,
but it might explain the title.

Tom

Ya know I am no expert on steel or iron. From surfing around it appears galvanized pipe (steel) is stronger than cast iron pipe and 'malleable cast iron' is the lowest strength of the 4 cast irons. No one talked about pipe thickness.

The 4 galvanized steel pipes I bought at Lowes last night seem just fine in my pipe clamps but cost $70 for the 4 of them and the malleable cast iron ones I found on Amazon cost $43 for 4 so the price is right.

[Stephen White]

To maximize my buying dollars I bought 10' sticks of 3/4" pipe at the BORG and had them cut at about 60:40. They threaded the ends for free. People talk about galvanized pipe slipping but, I have been using the same pipe for nearly 20 years and never had an issue. Pick up a few 3/4" couplers to have on hand for hooking pipes together. I keep mine on a piece of wire that hangs from the pipe clamp rack.

Ah bummer, lowes had 3/4 black pipe for $8 ea but was not threaded and didn't think to see if they would thread it for me. What is BORG?

[Bill Dufour]

I very much doubt any modern pipe is a malleable iron. Hard to cast long thin pipes for threading. Overkill for sewer pipe. Malleable threaded fittings yes. I bet they meant the pipe clamp castings were malleable iron.
Galvanizing has nothing to do with the underlying metal and adds nothing to hardness or strength. That is like saying painted pipe is stronger then powder coated.
Bill D

[Bill Dufour]

As a clamp I suppose malleable iron would be less likely to crack in two then cast iron when tightened up. But I bet malleable will end up cracking after some use.
Bill D

[Stephen White]

I very much doubt any modern pipe is a malleable iron. Hard to cast long thin pipes for threading. Overkill for sewer pipe. Malleable threaded fittings yes. I bet they meant the pipe clamp castings were malleable iron.
Galvanizing has nothing to do with the underlying metal and adds nothing to hardness or strength. That is like saying painted pipe is stronger then powder coated.
Bill D

Hey Bill, I think my original post and my replies are poorly written, I know nothing about pipes. Amazon sells 3/4 inch malleable cast iron pipes for $10 each in a package of 4, made by Pipe Decor. They are intended for furniture design. They are black, threaded 36" 3/4" pipes and look like they would work fine in my pipe clamps (a couple folks in the Amazon comments say they use them that way).

The pipe clamps I bought separately did not come with any pipe at all. I bought 36" 3/4 inch galvanized steel pipes last night for 4 of my pipe clamps at Lowes and it was expensive but they seem fine and I am pretty sure they are stronger than the iron pipes at Amazon. I was trying to figure out if the Amazon iron pipes would work.

[Stephen White]

As a clamp I suppose malleable iron would be less likely to crack in two then cast iron when tightened up. But I bet malleable will end up cracking after some use.
Bill D

yeah you are prob right, will just stick with the steel pipes I found at Lowes, seem like they will last longer than me.

[Lee Schierer]

Despite its name, black iron pipe is actually made of a low-grade "mild steel" compound. This gives it much better corrosion resistance than traditional cast iron piping. Black pipe is made of steel as is galvanized pipe. The difference is that galvanized pipe is coated with zinc, while black pipe is not. ... Black pipe is best used for gas lines, not for water lines because it rusts easily, while galvanized pipe is the safer pipe to use in water lines, but it cannot be used to convey gas.

There are sometimes problems using galvanized pipe with pipe clamps that utilize the tilted steel plates for locking the adjustable end in position. The older style clamps with the toothed cam do not generally care which pipe is used.

Pipe fittings can be cast or forged. Forged fittings are generally stronger.

[Rich Engelhardt]

Ah bummer, lowes had 3/4 black pipe for $8 ea but was not threaded and didn't think to see if they would thread it for me. What is BORG?

In the old Star Trek the Next Generation TV show, there was an alien entity known as - The Borg. They cruised through the universe assimilating everyone they encountered into this big giant collective.
Internet slang assigns the home centers - Lowes, Home Depot, Menards the handle of - The Borg - for there way of descending on a market - destroying to local small stores - and replacing all the decent goods and materials with sub-standard junk.

[Bruce Wrenn]

I don't think the actual pipe is malleable iron, just the fittings.

[Jerry Wright]

Been using pipe clamps for 50 years....and I am a real steelmaking and foundry metalurgist by profession. Never cared what the pipes were made of or the clamp jaws or threads were made of. I have whacked them tight with a hammer and never broken or bent any of them.....certainly not the pipes. To me they are the best for clamping any carcase or top.....unless you need deep jaws. Remember, all the clamp does is hold surfaces together. If they aren't square, parallel, or flat... the clamp can't help you. Source your pipes on price/availability and get into the shop.