pipe clamp slips on galvanized

[Tom Adger]

I use the common Pony pipe clamp for 3/4" pipe frequently. It slips quite a lot on galvanized pipe. I know you are supposed to use black iron, but where I am it is almost impossible to find. Does anyone have a solution for stopping the slipping?

[mike holden]

Tom,
To stop the slipping you need to either increase the diameter of the pipe or decrease the diameter of the locking plates. Neither is practical - although in a pinch I would try some shim stock shoved between the locking plates and the pipe.
Suggest you look into ordering some black pipe from one of the Borgs online, or the shiny pipe from Rockler.
Mike

[Chuck Wintle]

I use the common Pony pipe clamp for 3/4" pipe frequently. It slips quite a lot on galvanized pipe. I know you are supposed to use black iron, but where I am it is almost impossible to find. Does anyone have a solution for stopping the slipping?

I have the same problem and when it starts to slip I squeezed a little bit on the piece that is supposed to bite into the pipe. Once it catches then it could be tightened.

[Dave Sweeney]

Just take some sandpaper to the pipe and sand away the galv. coating. Galvanized pipe is nothing more than black pipe with a coating on it so you're not really dealing with two different pipe outside diameters here.

[Peter Quinn]

Tom,

Suggest you look into ordering some black pipe from one of the Borgs online, or the shiny pipe from Rockler.
Mike

I have a set of those shiny pipes from Rockler, they are 'Light Duty', not schd 40 iron, the ID is greater than black iron, the od is the same, the tube material is much thinner. I broke 4 of them at the last thread under a heavy clamping load. They work well for less demanding operations, don't slip and don't stain the work. Just not as strong as real gas pipe, so be aware of that. You won't get the 1200# a pipe clamp is capable of producing with those pipes.

I'd order some black iron. Sanding every galvi pipe sounds like no fun at all. If you are patient you might be able to get a supplier to get you some with there next shipment to avoid special shipping charges, don't know on that one. Might be a minimum quantity issue too? Worth checking.

[rob mason]

The Home Depots around here (MS) have racks of black pipe and I think they have already been threaded on one end.

[Lee Schierer]

Just take some sandpaper to the pipe and sand away the galv. coating. Galvanized pipe is nothing more than black pipe with a coating on it so you're not really dealing with two different pipe outside diameters here.The zinc coating is quite soft, so it should rough up rather easily with some sand paper or really stif wire brush. I have galvanized pipes on some of my pipe clamps and they don't slip, but the clamps use a toothed cam for gripping not the angled plates. I use only schedule 40 pipe, not EMT or tubing.

[David G Baker]

The older American made galvanized pipe does not have the problems that the newer stuff has. The older galvanized coating seems to be much harder and does not mar or smear as badly when using tools on it.
Black pipe is available where ever natural gas is used, check with your local plumbing and heating supply houses.

[Tom Esh]

Are you sure it's the pipe and not the clamp(s)? I've never had an issue with galv vs black, but I do have a couple clamps lying in the junk pile because the plate edges became dull or rounded. The plates simply could not have been up to hardness specs to begin with. I guess that shouldn't be big surprise given the other QC issues I've seen from all the leading brands.

[Howard Acheson]

I use the common Pony pipe clamp for 3/4" pipe frequently. It slips quite a lot on galvanized pipe. I know you are supposed to use black iron, but where I am it is almost impossible to find. Does anyone have a solution for stopping the slipping?

The solution is to use black pipe, not galvanized. Galvanizing is a surface applied coating and does not provide a good grip for pipe clamps.

The long time rule is to use black iron pipe for pipe clamps. They will not slip.

[Dave Lehnert]

Black pipe is impossible to find in Florida? Is it against code or something?
Around here black pipe is everywhere.

[Tom Adger]

Dave,

Here's how it is: If you read my post again, it says almost impossible to find. There is an industrial supply company in the next town that sells it in 21' lengths. After I pay for the cutting and threading, it is not worth it. Also, your post said that "around here" it is easy to find. I see you are from Cincinnati. Check your road atlas and see how far that is from South Florida. As one of the other posters said, it is used with natural gas. Down here, we have electric, and propane. Please focus on my original question, which was for a solution to slipping on galvanized.

[Don Eddard]

The long time rule is to use black iron pipe for pipe clamps. They will not slip.

I guess I missed seeing that page of the rule book. :rolleyes: I don't like black pipe, as it can stain the wood it's clamping. I have both, but I reach for the galvanized pipe clamps first.

To the OP, you might try a stiff wire brush on a drill motor to give the pipe a bit more "tooth" for the clamp to grab.

[Lee Schierer]

Dave,

Here's how it is: If you read my post again, it says almost impossible to find. There is an industrial supply company in the next town that sells it in 21' lengths. After I pay for the cutting and threading, it is not worth it. Also, your post said that "around here" it is easy to find. I see you are from Cincinnati. Check your road atlas and see how far that is from South Florida. As one of the other posters said, it is used with natural gas. Down here, we have electric, and propane. Please focus on my original question, which was for a solution to slipping on galvanized.
No need to get testy! In your area there are 12 within 50 miles and double that within 100 miles. There are also at least 1/2 dozen plumbing supply houses in the Ft. Pierce area according to Google. They all carry or will order black iron pipe. Also most True Value or Ace Hardware stores carry black iron.

Your solution for slipping on galvanized pipe is to (1) rough up the pipes you have a bit or (2) buy black iron pipe or (3) buy better clamps. The zinc coating (galvanize) on pipe is very thin and should sand off easily.

[Steve Clardy]

I have the same problem and when it starts to slip I squeezed a little bit on the piece that is supposed to bite into the pipe. Once it catches then it could be tightened.

Yep. Ditto that.

[Gene O. Carpenter]

Dave,
. Please focus on my original question, which was for a solution to slipping on galvanized.

Plug both ends then dip it in Muriatic acid for a few minutes then neutralize with Baking Soda and water rinse,dry thoroughly to prevent rust..
Back prior the 50's BIP & GIP came in 21' lengths was threaded both ends with a coupling on one end..BIP used to be coated with varnished to prevent rust and if they still use that type of protectant then that Varnish will fill the serrations on the Pawl in the sliding foot..
BIP was for gas and GIP was for water..And Brass pipe came in 10' lngths and was used by the elite..Then late 40's they started using copper tubing as we know it today..
So if you buy by the full length you might have to remove that layer of Varnish..
Gene

[Peter Quinn]

Belt sand that stuff?

But honestly, I reread your OP and you seem to be having a problem with galvi pipe, you yelled at a guy whose simple solution was don't use it, I'm lost. I understand the galvi pipe slipping, been there, don't buy galvi myself for clamps. I have a threader and a pipe cutter, but the borg near me cuts and threads for free, so i don't use it much, but as a kid working for my grandfather I threaded more black iron by hand then i care to recall. So GET A THREADER AND A CUTTER OR A SAWZALL, GET SOME THREAD CUTTING OIL, AND GET TO WORK! GAS PIPE IS CHEAP HERE, THERE AND EVERYWHERE, CHEAPEST GOOD CLAMPING DEVICE AVAILABLE.

Sorry if you don't like that answer but it seems the most logical answer to your query. Find good source for black pipe that won't rape you on cutting/threading charges and get back to working wood.

[glenn bradley]

This is interesting. I have seen this discussion before. I use Jorgie model 50's and can really crush things with them. No slippage on galv 3/4" pipe. Are these Jorgies?

[Loren Hedahl]

This is getting to be "fun".

You obviously haven't been enlightened to the myriad uses of drywall screws. Applications for their use have only had a surface scratching, as of yet and fine woodworkers are still back in the dark ages, for the most part, of using those nasty old pipe clamps that slip, stain and dent the nice piece they are building. What's more they are just temporary. Drywall screws are the answer to all these problems and offer a permanent clamping solution that I'm sure you will be most pleased to know about.

How about trashing all your pipe clamps with a good dose of vengeance and promise to never clamp anything again.

Then go to your local Borg and invest in a large selection of drywall screws and a drill set-up to match.

Use drywall screws to hold things together while the glue sets up.

If you don't like the finished appearance of the screws, you could either recess them and plug the holes, or remove them and putty the holes.

Oh! Too bad you are so far away, but I would be glad to take all your pipe clamps off your hands. You know, there ain't such a thing as too many clamps. But that comment is just for folks who haven't been enlightened to the use of drywall screws.

This has been fun, but to put this back into perspective, I do use quite a few drywall screws. Even though I have a deep appreciation into those who are purists in their woodworking hobby or craft, I'm not much into showcase woodworking. I build stuff to work and to hold up. I have a couple of pipe clamps, but I only use them to "square up" a cabinet occasionally. I have never had a problem with slipping on galvanized pipe.

Did I forget to mention, "This has been fun?"

[Dave Lehnert]

Dave,

Here's how it is: If you read my post again, it says almost impossible to find. There is an industrial supply company in the next town that sells it in 21' lengths. After I pay for the cutting and threading, it is not worth it. Also, your post said that "around here" it is easy to find. I see you are from Cincinnati. Check your road atlas and see how far that is from South Florida. As one of the other posters said, it is used with natural gas. Down here, we have electric, and propane. Please focus on my original question, which was for a solution to slipping on galvanized.

No need to get all worked up. I was shocked it was hard to find in your area. The reason for the question is it against code or something their. No harm in trying to learn something.
It is widely known that galvanized is not the best for pipe clamps. Black pipe is cheaper and better to use.

[Wayne Cannon]

It's been a long time (over 20 years), but the paperwork with Pony clamps used to specifically call for black pipe saying that galvanized pipe was slightly smaller in diameter, causing the slippage.

I have all black pipe (and some of Rockler's chrome pipe), but no galvanized, so I can't measure it to verify.

[Thomas Williams]

As mentioned earlier, you can kind of squeeze the clutch disks into the pipe as you tighten. You might also try turning the clutch disks around or rearranging their order.
Also, I measured the galvanized and black pipe I have. They are the same diameter.

[Peter Quadarella]

Loren, I'm not really sure if that post was serious or not, and there seemed to be some underlying humor that I missed, but if you are really using screws, wood screws would do a much better job of "clamping" than drywall screws due to their unthreaded shank.

Not that I would clamp stuff with screws except in a very few situations.

[glenn bradley]

This is getting to be "fun".

You obviously haven't been enlightened to the myriad uses of drywall screws. Did I forget to mention, "This has been fun?"

I just blew coffee onto my monitor . .. boowha-ha-ha-ha.

[Jules Dominguez]

I have several 3/4" Pony pipe clamps which are probably 20 or more years old. I've always used them on galvanized pipe and have never had a slipping problem with them.
I also have some 3/4" Craftsman pipe clamps which are even older - some of my first clamps - which have a spring-loaded toothed cam lock - and they do slip. I give the cam a firm tap with a hammer when I set the sliding jaw in position and they then hold with no problem.

[Bob Genovesi]

This is the reason I don't use galvanized pipes with pipe clamps.

I got a couple of lengths of scrap galvanized pipe and thought what a great find. They work with lite pressure but slip when more is needed. The ended up back in the scrap pile and I replaced them with black iron pipe from Lowes.

[Randy Cohen]

i've used both for a long time without any problem. i like galvanized more because its cleaner. i'd hate to have to buy it and then pay for shipping.

[Paul Saffold]

I have used conduit with no problems. It is soft so the clamps get a good grip. Yes, I know that many will say they bend under pressure, but I have had no problems with them with 3/4" clamps. If the wood parts fit together as they should a lot of force is not needed to hold them together. I'm not suggesting to use them in an application like steam bending, where you need a lot of torque.

Also you don't get black stains on the wood from conduit like you can with black iron.

Plus it is readily available, even in Florida! :eek:

[Dave Lehnert]

I have used conduit with no problems. It is soft so the clamps get a good grip. Yes, I know that many will say they bend under pressure, but I have had no problems with them with 3/4" clamps. If the wood parts fit together as they should a lot of force is not needed to hold them together. I'm not suggesting to use them in an application like steam bending, where you need a lot of torque.

Also you don't get black stains on the wood from conduit like you can with black iron.

Plus it is readily available, even in Florida! :eek:

Thats a great idea. Like you said I would be concerned with it bending but may be the answer clamping smaller work. The clamp will not be so heavy.

[Harley Reasons]

At the HD BORG I work at, we carry both 1/2" & 3/4" black iron pipe. I've cut and threaded lots of it for guys to use with Pony pipe clamps. We have never charged anyone for cutting and threading. With the Ridgid threader it only takes a few minutes to do it.
I have tried to use galv. pipe before and had slippage problems. I now only use black pipe. Just keep it wiped off and throw some johnson's paste wax on it every once in awhile and it works great.

[Seth Poorman]

I just blew coffee onto my monitor . .. boowha-ha-ha-ha.

LOL !!!!!!!!!!!!!

[Alan Schaffter]

I hate to say this, but I believe everyone missed the mark on this one!! It is like telling someone who is having trouble cutting bread to get different bread instead of sharpening his knife!!!

The black pipe or black "iron" pipe available in home centers and used for plumbing gas is actually steel pipe. Galvanized pipe is steel pipe that has been "hot dipped" plated with Zinc. Zinc is softer than steel. Your pipe clamps should work with either type of pipe, but actually better with galvanized.

Your problem is that the "grippers" are no longer grabbing the pipe because the edges of the gripper holes are no longer sharp. (They are likely made with a cheaper and softer grade of steel these days)

Most Jorgensen Pony style (orange) pipe clamps (and similar models from Grizzly, Irwin, Rockler, Stanley, Woodcraft, Bessey, etc.) have three gripper plates. The edges of these grippers actually dig into (by spring force) and are wedged against (by clamping pressure) the pipe and prevent the fixed end of the clamp from moving. What has happened is that the corners at the top and bottom of hole where they are supposed to grip the pipe are no longer crisp and sharp, having been dulled by use and from sliding the fixed end without retracting the grippers.

These grippers are held in place by a spring and can easily be removed (they just slide out) after removing the unit from the pipe. A little touch up of the gripping edges with a file should take care of your problem. Also, the spring which causes the plates to initially engage the pipe, may be weak or compressed. I have never replaced the spring but that may be easy also.

Now, if you have the Sears style of pipe clamp (red) (or the Shop Fox and Fuller), you have an entirely different animal- it has a single serrated arm gripper that is not easily removed- you must drill out a rivet. If you retract the arm to its limit, you can get a file on and sharpen about half of the serrations.

Try your hand at filing the grippers on your worst clamp- what do you have to lose.

Better yet, start saving up for some Besseys.

[Harley Reasons]

The black pipe or black "iron" pipe available in home centers and used for plumbing gas is actually steel pipe. Galvanized pipe is steel pipe that has been "hot dipped" plated with Zinc. Zinc is softer than steel. Your pipe clamps should work with either type of pipe, but actually better with galvanized.

Try your hand at filing the grippers on your worst clamp- what do you have to lose.

Better yet, start saving up for some Besseys.

Alan, I beg to differ on your statement that the clamps should work better on galvanized pipe. If so, then Pony would recommend the galvanized. Here is a quote from their website description "The PONY Pipe Clamp Fixture is one of the handiest tools in any shop. One set of PONY Pipe Clamp Fixtures can be used to make any number of different length bar clamps simply by using the fixture on different lengths of pipe. Heavy-Duty black pipe is recommended." (Adjustable Clamp Co. (http://www.adjustableclamp.com/cf50.htm)) (Link for reference purpose only).
Additionally, pipe clamps have their place in the great scheme of clamping. Especially if you need to clamp very long pieces. I have used up to 20 ft of pipe when building decks to pull a board or joist in line. Also, I seem to remember that pipe clamps had even greater clamping pressure than the parallel jaw clamps. I own both type and use the clamp appropriate to the job at hand.
As to the slippage problem, galvanization is a smooth surface that prevents the gripper rings from getting a bite. I've had clamps to slip on galvanized pipe but transfer the same clamps to black pipe and they work as expected.
I think the advice given to use black "steel" pipe is dead on accurate to cure the OP's problem.
I did learn one thing from your post though, I hadn't ever thought of disassembling the gripper rings and filing on those. Thanks for that tip.

[Alan Schaffter]

Alan, I beg to differ on your statement that the clamps should work better on galvanized pipe. If so, then Pony would recommend the galvanized. Here is a quote from their website description "The PONY Pipe Clamp Fixture is one of the handiest tools in any shop. One set of PONY Pipe Clamp Fixtures can be used to make any number of different length bar clamps simply by using the fixture on different lengths of pipe. Heavy-Duty black pipe is recommended." (Adjustable Clamp Co. (http://www.adjustableclamp.com/cf50.htm)) (Link for reference purpose only).
Additionally, pipe clamps have their place in the great scheme of clamping. Especially if you need to clamp very long pieces. I have used up to 20 ft of pipe when building decks to pull a board or joist in line. Also, I seem to remember that pipe clamps had even greater clamping pressure than the parallel jaw clamps. I own both type and use the clamp appropriate to the job at hand.
As to the slippage problem, galvanization is a smooth surface that prevents the gripper rings from getting a bite. I've had clamps to slip on galvanized pipe but transfer the same clamps to black pipe and they work as expected.
I think the advice given to use black "steel" pipe is dead on accurate to cure the OP's problem.
I did learn one thing from your post though, I hadn't ever thought of disassembling the gripper rings and filing on those. Thanks for that tip.

They give no reason or justification for their statement, maybe they want to save customers money? Frankly, I think the operable words in their statement are "Heavy-Duty" and not the "black pipe" first, since they capitalized both Heavy and Duty, and the fact that you can buy pipe in a wide variety of thickness with 1/2" or 3/4" NPT on them. Many are thin-walled, not rigid, and not suitable for pipe clamps. The galvanized covering on the pipe at my local Borg is not smoother and in fact rougher than the black pipe. The black pipe is also often covered with smooth scale which can chip off. Look at the difference in Rockwell hardness between Zinc and steel- the grippers will dig into Zinc much more easily and not dull the grippers as quickly. Remember the grippers are steel also, but are (supposedly) hardened enough to dig into the pipe. That is what they are designed to do, I can show you spots along my pipe where the grippers have left ridges in the pipe after an especially tight clamping. As I said, regardless of pipe type, the key to this problem is dull grippers and/or weak springs.

Of course we haven't discussed wax, glue, or finish contamination of the pipe or grippers either. How many folks wax their pipe to protect it or to protect their project from pipe stains? They are increasing the chances of the tail stop slipping by doing this. Also, how many folks slide the tail stop forward without holding the clutch (grippers) so the grippers don't wear down? How many folks whose clamps are slipping are using their father's or grandfather's pipe clamps whose grippers are likely to be worn down or that have weakened springs?

I use both types of clamps too, but given the choice, for anything less than about 50", Besseys though expensive (and even more so now!) are my overwhelming clamp of choice.

[Tom Adger]

Whew!

Thanks for all the replys. Especially those that addressed the original question.

If I had to judge the most useful replys, it would be to: 1. sand or grind off the zick coating. This, however, has inhalation problems. Use a good mask. 2. Hold the rings in place when attempting to tighten. Simple, but effective. 3. Take the retaining spring out, turn the rings over to have a fresh, sharp edge.

Tom

[Jim Kountz]

Actually if you're getting alot of slippage you might want to check your joinery. A properly fitted joint just does not or rather should not require much clamping at all. When you have to really lay on the pressure to close a joint, its not a good joint to start with. Not trying to offend anyone here just stating facts.

[jack duren]

Actually if you're getting alot of slippage you might want to check your joinery. A properly fitted joint just does not or rather should not require much clamping at all. When you have to really lay on the pressure to close a joint, its not a good joint to start with. Not trying to offend anyone here just stating facts.

Perfect jointery still requires good pressure.

[Alan Schaffter]

Whew!

Thanks for all the replys. Especially those that addressed the original question.

If I had to judge the most useful replys, it would be to: 1. sand or grind off the zick coating. This, however, has inhalation problems. Use a good mask. 2. Hold the rings in place when attempting to tighten. Simple, but effective. 3. Take the retaining spring out, turn the rings over to have a fresh, sharp edge.

Tom

#3 sounds like a good quick fix. I would be interested knowing how this works. Please keep us updated. #2 should be a normal procecure, but not always easy to do because of possible separation of the two parts.

[Jim Kountz]

Perfect jointery still requires good pressure.

Adequate pressure yes, but alot of pressure? Absolutely not. In some cases too much pressure can actually make a joint weaker by squeezing out too much glue causing the joint to fail. If you're talking about everyday glue ups like mortise and tenon joints, making up panels and such, the pressure required on good fitting joints of these types should not require so much pressure that clamps start slipping on the pipe, be it galvanized or not. I use both and have for years and mine dont slip. Your mileage may vary of course. Honestly, I wouldnt lie to you!! LOL :D:D

[Rich Engelhardt]

Hello,
I clean the galvanized with lacquer thinner and shoot a light coat of aerosol hair spray on.
Problem solved.

Technically speaking, zinc is a lubricant to steel.
Steel will not gall zinc.

The hair spray (which is really a lacquer) provides the same type of surface black pipe has.
Black pipe is simply lacquered steel.

[Howard Acheson]

Actually if you're getting alot of slippage you might want to check your joinery. A properly fitted joint just does not or rather should not require much clamping at all. When you have to really lay on the pressure to close a joint, its not a good joint to start with. Not trying to offend anyone here just stating facts.

Both adhesives manufacturers and the US Forest Service Wood Products Lab recommend 200-250 psi for clamping hardwood joints. As most 3/4" black iron pipe clamps can exert about 1,000 psi when fully tightened it required one clamp, fully tightened every 5-6 inches to get a full strength joint and minimum glueline on 3/4" stock.

I agree though, that you should have good, close fitting joints to start with and not rely on clamp pressure overcome poor joinery.

[Will Blick]

> Perfect joinery still requires good pressure.

Yep, just talk to a wood glue maker... very few people apply enough pressure, even on perfectly cut joints.... as the rating is PSI, and when you add up the sq. inches, you see how much total pressure is required, then when you consider that each clamp delivers way less than than you think, i.e. 600 lbs of force vs. 1000 lbs of force, we all tend to be short. However in most cases, the joint is still strong enough for its intended purpose, BUT, your glue line may be more visible than it could have been.... this is the other purpose of adequate pressure....



> Adequate pressure yes, but alot of pressure? Absolutely not. In some cases too much pressure can actually make a joint weaker by squeezing out too much glue causing the joint to fail. If you're talking about everyday glue ups like mortise and tenon joints, making up panels and such, the pressure required on good fitting joints of these types should not require so much pressure that clamps start slipping on the pipe,


Its too bad there is not some permanet stickies up on this subject, as its re-visited over and over. It's almost impossible to provide too much pressure with hand tightened clamps. Yes, there is that rare situation when you can over clamp, such as very thin sheet goods with clamps spaced every 2". But at the same time, many joints such as M&T provide all their strength via the joinery itself, not the glue. So, of course, some common sense must be applied here. There is many applications where there is no visible glue line that you are trying to conceal and there is no extreme pressure at the glue line, in which case, clamp pressure is almost a non-issue.... blue tape would provide sufficient pressure :-)





To the OP....sometimes threads go off on small tangents, not such a bad thing...this was stayed on course pretty well IMO....


As for the Galvanized issue, or pipe clamps in general.... I bought some of the Galv. with new Rockler pipe clamps...and they slip like crazy. Rocker suggested removing some of the inserts.... clearly, a smooth surface is hard to bite into. Many people think their pipe clamps do not slip at all..... I put a pressure meter on mine, at different distances....and in some areas the slippage was very consistent, each few minutes, I lost another 10 - 30 lbs of clamp pressure....other areas it may have lost the same pressure over 30 minutes. It was not uncommon to start at 800 lbs of pressure, and 30 minutes later, bet at 1/2 that force. Without a gage, this fools all of us. The black iron pipe slips to, but at levels that are very acceptable. Steel has mostly iron in it...


This is an overlooked advantage of a well designed parallel clamp.... almost none of them slipped in my testing...