Reconstructing a Cracked Radiator

gliptitude

This radiator has one badly cracked section. I cut the four tie rods and removed the bad section, along with the four good sections in front of it.

Unfortunately the bad section took all four of the joint push nipples with it.

I thought I could cut this radiator section up with a saw zaw to get the push nipples out, but I haven't tried this yet.

.. I notice that these fittings are different lengths, (see last photo). Is this something I need to pay attention to and keep in order?

.. What steps should I take to reassemble the radiator?

BobC

You can buy new push nipples, hopefully someone will contribute the name because I can't think of it off the top of my head but a search turned up this -

" You can get replacement push nipples from Oneida County Boiler Works if needed."

Bob

Fred

I think those nipples are the same. Are you sure one isn't just pulled out more than the other, when you seperated the sections? I don't know about trying to reuse those nipples. They will likely leak???

Paul48

Clean them up, use some form-a-gasket, and reuse them.

gliptitude

Yes i had never considered buying new nipples. I hadn't heard that mentioned in the video i watched or in the old forum threads i read.

Maybe the longer ones are just pulled out from the separation. IDK. I guess I assumed they were slightly tapered for some reason, but i guess they are just straight so there is no perfect length alignment?

.. The other stuff I read says it shouldn't be necessary to use sealant but they do it anyway. One used black dope another used a "light bead of pure silicone" and Paul48 says form-a-gasket. Could I just as well use the Rectorseal no. 5 that I already have handy?

vaporvac

There were a couple of in depth threads on the subject last year. I'll try and search for them.
p.s. I think it's funny you consider Cincy a wasteland for hydronics. I live there too and consider it a goldmine of old steam and HW systems.

gliptitude

vaporvac said:

p.s. I think it's funny you consider Cincy a wasteland for hydronics. I live there too and consider it a goldmine of old steam and HW systems.

Hey, you must have read my other thread.

Well maybe my point of view is skewed as far as Cincinnati and the rest of the world goes. I'm just rehabbing my own home in my spare time and observing other more successful rehabbers in my neighborhood and other neighborhoods that have lots of development going on. Many of these old homes have hydronic systems but the process of transforming a 20K distressed building into a 200K home seems to always automatically entail forced air heating, (and central air).

If my plan was to flip this house I probably would have taken a much different direction by now.

KC_Jones

gliptitude said:

Many of these old homes have hydronic systems but the process of transforming a 20K distressed building into a 200K home seems to always automatically entail forced air heating, (and central air).

And a HUGE decrease in the comfort of the home. I grew up on forced air and if anyone thinks a "typical" forced hot air is even close to hydronics I would argue that point to my death. People in this country have been buffaloed into stupid when it comes to this topic and I can't stand it. I have a friend that recently downsized their house because the kids are going off to college. They went from a 4500 sq ft forced hot air (very high end house) to a 1500 sq ft hot water baseboard (built in 1949). He said after one week of heating he will NEVER EVER own another forced hot air house. He decided that in one week. I find that very telling. I have steam and my house is the only one my mother doesn't wear extra layers in. She is always cold, except when she comes to my house. Sorry for the hijack I get pretty passionate when I read about people tearing out these systems...makes zero sense to me.

Paul48

@gliptitude

Check out high temp RTV. The push nipples are tapered. Keep in mind, the casting of sections may be from different years, and the holes may have been finished by different machinists. One may have been using new tooling and one old, and they both were within tolerance. Worn, re-sharpened tooling makes a smaller bore.

gliptitude

Thanks for the suggestions. I'll keep in mind.

I have removed and cleaned the four push nipples, according to my intended method. .. They do appear to all be identical, so i'm not going to worry about one having stuck out further than the others.

I knicked one of them pretty good, but i think i only need two of the four anyway.

.. KCJones, i agree with you, however i am a pretty stingy **** myself. Hydronic is definitely what i wanted but had i had to start from scratch it is doubtful i would have been able to bring myself to make the initial investment. .. And as it is in the current situation it was a pretty tough decision to go this rought when most indications are that this probably actually detracts from the value of my home in this market. .. Maybe it wouldn't if i really made a show of it and designed a model system. But that is way beyond my means and abilities right now.

vaporvac

I have never heard of a hydronic system as a "detract" in this market. However AC is the issue. There are many options for adding that and keeping the HW. It's really the best of both worlds. Since you're living in the house, it's your comfort that matters.
HW is very common in certain areas, particularly the NE. My Dad installed it in his new build in Maine because it's a comfort issue. Of course, he was able to design and install himself. There's also a cleanliness factor to consider. Dust flying everywhere with FA. Friends with allergies always wonder why, even with a long-haired cat, they're never bothered when visiting. It's up to us to inform others. it wasn't such a problem not too long ago, but now total gut jobs seem par for the course. I don't get it.

KC_Jones

gliptitude said:

And as it is in the current situation it was a pretty tough decision to go this rought when most indications are that this probably actually detracts from the value of my home in this market. ..

If that is indeed true I would have to assume every realtor in your area has an IQ lower than Forrest....wait all the ones in my area praise the worst builder I have ever seen. Must be an epidemic. lol

gliptitude

There's a lot to be said on this subject and i think we're mostly just going to agree with eachother.

.. But we need to get my radiator put back together first!

KC_Jones

Apologies for the hijack, maybe this will actually be useful.

http://forum.heatinghelp.com/discussion/152123/where-to-get-push-nipples-for-cast-iron-radiator

or if you don't feel like reading this.
oswaldsupply.com/boilers-heating-supplies/nipples/radiator-push-nipples.html

Even if it isn't useful at this point still good for anyone that might stumble upon this.

gliptitude

I think i'm fine with the old push nipples, but that could be useful to others. .. I do hope this is successful and that a pretty clear documentation of the process remains here for others to review if they try to do this.

.. i think i should have tipped the radiator on it's side for initial assembly. Instead i just had the middle sections on blocks. I'm really not sure how i could have tipped this one over though, even if i had an extra hand, let alone tip it back up afterwords.

Also for the loose nipples, i think this might have gone easier if i had completely installed each one on one side. Instead i just kind of inserted it between two sections and assumed it would tighten up enough as I cranked the tie rod bolts.

The end section with legs, which i had removed by itself, inserted most of the way fairly easily, very early in the tightening process.

I think i'm going to need some better tools to finish this.

gliptitude

Having a hard time getting it all the way together.

kcopp

you may need a hydraulic jack...

gliptitude

.. Well I think I've worked it out, as far as tightening up the radiator assembly.

I changed several variables, but I'm pretty sure that the critical one was changing the hardware. I got better, thicker washers and I salvaged the four original nuts. (Still using four hardware store nuts on one side because my bolt is threaded on both ends unlike the original).

The original nuts are kind of unique, or at least different from what was available at either Home Depot or the local hardware store. The outer dimensions of the original nuts are larger than typical nuts with that same inner threaded dimension.

The holes that the bolt goes through on the radiator are almost big enough for the nuts i was using to fit through, and the washers were getting deformed.

BobC

There are different classes of nuts, the originals were probably heavy hex nuts.

http://www.mikesenese.com/DOIT/2011/10/visual-glossary-of-screws-nuts-and-washers/

Bob

JUGHNE

Someone may know for sure, but do you keep those tie rods tight after everything is drawn up? I thought I read about boiler sections that you loosen the nuts to allow for expansion of the sections....Much higher temps in boiler, but the CI rad will want to expand somewhat......FWIW.
I have never done either assembly myself, so just thinking.

KC_Jones

I haven't done a radiator, but have done a fair amount of press fit operations such as this. The difficulty (because of plugs) on these rads is you can't get down the center line of what you are trying to assemble. The perfect way to do this operation would be to put a rod down the center of the connection with heavy steel plates on either side. Pulling down the center line will always go smoother because you are loading the push nipple equally on all sides. The other advantage is you could use a very heavy rod and nut for strength and allowing the use of much larger wrenches for leverage. The problem with the old rads is those damn plugs are in the way so it makes life difficult. Oh and BobC hit the nail on the head those appear to be extra heavy nuts. Need to find a real hardware store or fastener supply company, the big box won't usually have specialty stuff like that. Looks like you are doing a great job BTW my hats off to you!

gliptitude

Maybe I will swap in heavy hex nuts in the future then. I think it's fine for now though. The thick washers made a huge difference. The original assembly had no washers.

JUGHNE said:

Someone may know for sure, but do you keep those tie rods tight after everything is drawn up? I thought I read about boiler sections that you loosen the nuts to allow for expansion of the sections....Much higher temps in boiler, but the CI rad will want to expand somewhat......FWIW.
I have never done either assembly myself, so just thinking.

Hmm. Good thought. Makes sense to loosen them i think. I'd like to find confirmation first from someone who has done it though.

In the mean time i've got some work to do getting this plumbed back up.

I am concerned about heat expansion and the bolts. I'll fill cold and check for leaks first. I guess i really don't know if any of this worked yet and the plumbing is going to be pretty tricky the way i'm trying to it, (using the old fittings).

gliptitude

.. And i definitely understand about the ideal press fit setup, which was impossible in this case. I tried to zig zag between the bolts, and be as even as possible throughout the process. But it is (just barely) observable that the inner portion of each joint (closer to the bolt) is tighter than the outer. I'm afraid to tighten any more at this point because it's mostly just going to put more pressure on the inner portions.

Fred

Makes you wonder why no one has developed a silicone nipple to replace those old nipples. Something that would compress and conform to the mated structures. I even wonder why, in years past, those nipples weren't brass or some other softer metal that would conform.

ChrisJ

Fred said:

Makes you wonder why no one has developed a silicone nipple to replace those old nipples. Something that would compress and conform to the mated structures. I even wonder why, in years past, those nipples weren't brass or some other softer metal that would conform.

Why don't you Google "silicone nipple" and click on images. I dare ya.


I assume there's a reason, modern boilers still use steel push nipples and basically the same setup. Maybe it's cost.

Fred

ChrisJ said:

Fred said:

Makes you wonder why no one has developed a silicone nipple to replace those old nipples. Something that would compress and conform to the mated structures. I even wonder why, in years past, those nipples weren't brass or some other softer metal that would conform.

Why don't you Google "silicone nipple" and click on images. I dare ya.


I assume there's a reason, modern boilers still use steel push nipples and basically the same setup. Maybe it's cost.

LOL, Wrong Nipple, BTW WM, They use a rubber O-ring of some type but you already know that.

gliptitude

.. Can any one else weigh in on whether or not I should loosen the rods/nuts before heating it up? I expect to be testing it out tomorrow afternoon.

ChrisJ

gliptitude said:

.. Can any one else weigh in on whether or not I should loosen the rods/nuts before heating it up? I expect to be testing it out tomorrow afternoon.

@Steamhead Can you help?

Paul48

I forgot to mention that the RTV would act like a lubricant.

BobC

I have read cautions against over tightening the rods but I have no idea what the proper tension is. I know my rods are tight but how tight is tight?

Bob

Boiler wrestler

I've split and reassembled several, reusing nipples with just pipe dope and never backed the nuts off and haven't had an issue.

gliptitude

.. Plumbing the shortened radiator up was tricky but it seems to have worked out. No leaks in the radiator or the pipes. I loosened the nuts only a tiny bit.

.. Unfortunately another radiator, which i attempted to patch with JB Weld, failed horribly. (Finally burst after the radiator got really hot.)

I feel good enough about the section removal/reconstruction process (and bad enough about the JB Weld patching) that I'm going to go ahead and break down two more radiators. Not sure how i will orient them yet. I think that i could shorten the longer one to replace the smaller one without modifying the plumbing, (which is concealed in a closed crawl space).

Jamie Hall

The danger with the tie rods comes when you are tightening them up in the first place. They heat at almost the same rate as the radiator, so differential expansion is not a problem.

It is possible to break or strip them if one is a bit of a gorilla when you are tightening them, though.

gliptitude

.. Ok, so maybe i won't worry about the rods and loosening the nuts anymore.

.. I just read through this whole thread again. Small thing i forgot to mention, (this is mainly for any amateurs that might read this thread some day looking for directions on how to do this), i did NOT cut the old nipples out with a saw zaw. I used an angle grinder. Saw zaw would have taken forever and been an even sloppier job.

gliptitude

Well i really lucked out with the two failed JB Weld repaired radiators. They were compatible with each other so i was able to make one good one out of the two bad, exactly the same size so i didn't have to change plumbing. Even the push nipples came out / didn't come out, exactly the way i needed them to so that there was no extra nipple extraction to do.

Boiler has been running for almost six hours now, without incident.

It is so warm in here, i can't believe it! This is wonderful!

gliptitude

.. One interseting thing i noticed on these radiators, which was not the case on the first one that i broke down, is that the push nipples are two different sizes. The channel at the bottom is larger than the one on top.

Fred

Great!