Can I do it to Conduit?

I know for septic systems, a box with heater strips is used to create minor sweeps. Hopefully Bruce Bergman will pipe up. If not, I'll query my brother who is a master electrician. Maybe he has an opinion or can ask around.

I've made impovised metric tubing by warming inch tubing and either shrinking it in a ring or shoving a turned piece of metal inside so it would fit those push fittings.

Wes

I have heated 2 inch electrical conduit with a torch. Buggered some pieces but then got the hang of it. At the time I did not have a heat gun. Should work fine on 2 inch, I don't know about 4".

Ivan Vegvary

Yes, and NO! :-) Assuming you are running an electrical circuit in this electrical PVC (? SCH 40) conduit the new 2008 NEC says that "field bends shall be made only with bending equipment identified for the purpose." This would exclude an industrial heat gun. Art. 352.24; Bends - How Made.

However, I think the "key" to the situation is in the sentence just before the one quoted above . Bends shall be so made that the conduit will not be damaged and the internal diameter of the conduit will not be effectively reduced.

It shall not be used where subject to ambient temperatures in excess of 50*C (122*F).

My thoughts: This conduit melts at close to 122 degrees F, I think. IF it is going to be exposed so an inspector can see that the diameter is not greatly reduced, and that the chemical characteristics have not been effectively changed by heat; i.e. burned, crystallized spots, etc. and the ambient temp is acceptable grab the heat gun and go to work.

Keep it mind: Minimum radius for that conduit. Keep the gun at a distance and keep it moving . Keep the pipe rolling so you heat all the way around and for the needed distance to make a gentle bend. Wear gloves (? welding gloves). If you have an attachment to help spread / flare the flame it would help heat a larger area more evenly. You may want to angle the gun about 15 - 30 degrees off parallel to avoid burning spots and leaving others cold.

I know someone who heated some over a large burner on his electric range, but it was only 3/4" or 1" conduit and much easier to handle. It will seem as if you're getting no where and all of a sudden it is flopping around if you get the heat too close. Be ready to back off on the heat distance to maintain needed heat as in delicate brazing. Be prepared to hold the angle you want while the pipe cools again. I would not douse it with water to cool it as you may crystallize the pipe.

Let us know how it works out.

Plan B: Determine how much off set or bend you need. Find someone with the proper equipment, usually an electrical contractor, and have them make you the bend or offset.

I DO NOT recommend this and DID NOT recommend it to the other fellow referenced above with the smaller conduit. "It is illegal"! per above reference - but it can be done (with smaller conduit) just not easily. When you finish you may wish you'd spent the money for the sweeps. ;-)

Hope everything goes well, regardless of which route you choose.

Al

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jusme wrote:

"Ivan Vegvary" wrote: (clip) I have an industrial heat gun. (clip) ^^^^^^^^^^^^^^^^ If you mean an electric heat gun, like an industrial strength hair dryer, it won't do it. I would recommend an oxy-acetylene torch with a medium size rosebud tip. You need to reach close to red heat, evenly distributed over the length of the bend.

With a smaller tip, you can do wrinkle bending by going to red heat halfway round and then pulling in the bend--one wrinkle at a time.

Sounds like bending *metal* conduit. He's talking PVC.

Second Thought: Do NOT get back on here and confess that you did it in a non-compliant way or with non "identified for the purpose" equipment.

Your inspector might read this newsgroup! ;-)

Al

For slight bends in the 4-degree to 22 degree range you can bend it yourself, or for long sweeping bends just dig the ditch in a long curve and force the bend in as you drop in the pipe.

But for 45 or 90 bends you are much better off buying the sweeps pre-made - depending on whether this conduit is for LV electric, MV electric (semi-conductor jacketed cables) telephone or fiber-optic cables they all have minimum bend radius requirements. And the inspector from the power or phone company is going to be very picky if you don't meet the requirements they asked for.

If your homemade bend is smaller than the minimum bending radius of the cables, or has a kink in it that reduces the ID past the OD of the cable and the pulling grip, the cable will be difficult or impossible to pull through the conduit. And you'll have to dig it all up and do the whole job over, this time with the right factory made sweeps.

If this is plastic Schedule 40 conduit you certainly can heat bend it yourself, but a heat gun is not the best choice of tool - not enough energy for the large stuff, and even heat distribution is critical if you don't want to scorch the plastic. And if you distort the plastic at the ends of the length, you'll never get standard conduit fittings on it.

They make heat bending boxes that are 3' to 5' long with several long Calrod IR elements inside, a hinged top to retain the teat yet allow drop-in access with the conduit, and steel "skate wheel" rollers so you can keep the conduit spinning by hand (rotisserie style) till you reach the 'plastic stage'.

Then you remove the conduit from the box, bend it into the desired shape, and set the bend with a spray bottle of cold water.

There are also 'heating blanket' style bending heaters, but they are much slower and a pain to work with.

You could improvise a heat-box bender of your own with a clean gas barbecue, a set of steel caster rollers to carry the conduit as it spins and warms up, and a block so the partly closed BBQ lid leaves a gap for the conduit to hang out at the ends as you spin it by hand.

And you can adjust the heat a lot easier than a heat gun, and the length of the heated zone by how many burners you light.

-->--

Yes, you can. Job benders for PVC are nothing more than a heat box you lay the pipe in.

I think..with 4", Id (carefully) use a rosebud on your torch, if you have one.

And if possible, bend it around something like a drum or whatnot.

And wear gloves, its gonna be HOT

Gunner

"Pax Americana is a philosophy. Hardly an empire. Making sure other people play nice and dont kill each other (and us) off in job lots is hardly empire building, particularly when you give them self determination under "play nice" rules.

Think of it as having your older brother knock the shit out of you for torturing the cat." Gunner

} this electrical PVC (? SCH 40) conduit the new 2008 NEC says that "field } bends shall be made only with bending equipment identified for the } purpose." This would exclude an industrial heat gun. Art. 352.24; } Bends - How Made.

All ... could you *please* configure your newsreader to fold outgoing lines at perhaps the standard 72 characters? I'm having to scroll the window sideways and back several time to read what you post, or at least I did until I gave up on it as not worth the trouble.

Note that I've folded the one line I bothered to quote, preceding the extra sections with a '}' instead of the traditional '>', and it wound up occupying four and a quarter lines.

Thanks, DoN.

On Sun, 06 Apr 2008 03:44:44 +0000, DoN. Nichols wrote: ...

Try the W key; in slrn that toggles wrap_article. What happens next (ie, what gets wrapped) depends on wrap_flags. See section

6.134+ in

DoN,

How about this. I've selected 60 characters to allow for quotes, etc. I'll make this paragraph several lines long so you can tell me if it wraps as it should. Is anyone else having a problem with my lines not wrapping?

Thanks,

Al

============

D>

Works for now.

Scott

Good advice on GP, however...

Hit W and slrn will wrap your display for you. No scrolling necessary. Also configurable in .slrnrc

% What to wrap when wrapping an article: % 0 or 4 ==> wrap body % 1 or 5 ==> wrap headers, body % 2 or 6 ==> wrap quoted text, body % 3 or 7 ==> wrap headers, quoted text, body % The higher number indicates that every article will be automatically % wrapped. set wrap_flags 4

Most readers can be configured to automatically wrap long lines....

That's what I thought. Mine is configured that way, but I recall a time or two when I'd get a msg. that just didn't wrap. Possibly I'd hit a wrong key somewhere and caused it myself. I also have many TSR's running so one or more of them may have had a conflict. There is a program or two that work great alone, but I have to shut them down to work with others ..... conflicts.

[ ... ]

Thanks! I'll try that.

But it still could be a problem if I decided to followup to the article in question. My preferred editor (jove) truncates the file it is reading in the first time it hits a line longer than 1024 characters, and truncates that line to the length of 1024 characters too. So a followup with full text to quote would require saving to a file, folding the lines in the file with another tool, and then reading it in when the editor truncated.

I could get around this by using emacs instead, but I like jove for so many reasons. :-)

Thanks, DoN.

It does exactly as it should. Actually, the suggested length of

72 is to allow a certain amount of quoting anyway, because the typical screen width is at least 80 characters (what was present in hardware terminals which could not be changed), and is often the default width on windows on other systems.

It will depend on what software they are using as a newsreader. I just received a suggested command to turn on wrapping in my newsreader (not yet tested). But it still could create a problem if I opted to follow-up to one of your articles before the change, because my editor truncates at the first line with more than 1024 characters in it. That would be typically somewhere around twelve lines on your screen if not folded in outgoing.

Thank you, DoN.

Done now. I'm not sure whether it will work on this version yet, since it was not included in the sample .slrnrc file (while a lot of other things were), so I may have to chase down the source and compile a newer version than what came pre-compiled with Solaris 10.

It will be interesting to see what this does when an article is sent to the editor for a followup. If the folded lines are sent folded, I will be fine. Otherwise, I may occasionally hit problems with lines over 1024 bytes long -- unless I switch from jove to emacs. Yes, I know that emacs is more powerful, but I'm very familiar with jove, having used it since about 1985 when I ran it on systems too small to handle emacs properly. :-)

Thanks, DoN.

Your version number is identical to mine. One would think it should have all the same options regardless of platform. The .slrnrc that comes with both the FreeBSD and Debian ports both have the wrap option template... actually, I just checked the old .slrnrc that I was using on Red Hat 6.2 and even that had the wrap option included. I'm guessing it was 0.9.7.x.

I use nano because my first unix MUA was Pine, so I got used to pico. Even though nano was smaller, it actually had more features. The one that sticks in my mind was the "search & replace all instances of x with y" Pico still doesn't have that feature even in the latest release... and nano is still smaller than jove. ;-)