Sheet steel tender tank sealant

This forum is dedicated to the Live Steam Hobbyist Community.

Moderators: cbrew, Harold_V

User avatar
milwiron
Posts: 156
Joined: Sun Jun 07, 2020 1:52 pm
Location: Flanagan, IL.

Sheet steel tender tank sealant

Post by milwiron »

With the horrendous cost of brass it's time for me to start considering building a tender out of steel sheet, possibly galvanized. I have worked a lot with stainless but it's hardly an economical alternative.
I've read through the archives and there doesn't appear to be a consensus on sealants. Any successes out there on a coat-and-forget modern sealant?
Please don't mention Phil Swift and Flex Seal, I've tried it around the house, it doesn't work well for anything.
Thanks much,
Denny
"Measure twice, curse once."
User avatar
SPSteam2491
Posts: 271
Joined: Tue Feb 21, 2017 2:30 pm
Location: Mukwonago, WI

Re: Sheet steel tender tank sealant

Post by SPSteam2491 »

I have used gas tank sealant (from KBS) in the past on a tender and it's starting to peel after 10 years of use. It took a solid 8 hours of preparing the metal and applying the sealant and will likely take 4+ hours to remove the sealant. I wouldn't do that again if I was starting a tender from scratch.

I'm building a new tender now in which the exterior shell will be sheet metal with rivet details, edge rounding, etc. The inside will be a separate welded aluminum water tank. This skips the need to find a robust waterproof coating that holds long term coverage for submerged water coated metals and allows common paint methods to be used for the exterior of the tender.
Thanks
John LaFavor
Pacific Design Shops
Pontiacguy1
Posts: 1566
Joined: Thu Apr 26, 2012 10:15 am
Location: Tennessee, USA

Re: Sheet steel tender tank sealant

Post by Pontiacguy1 »

There is a gas tank sealer called Red-Kote that I and some of my friends have used and it seems to work extremely well.
Soot n' Cinders
Posts: 983
Joined: Wed Jun 27, 2012 5:24 pm
Location: Marietta, Georgia

Re: Sheet steel tender tank sealant

Post by Soot n' Cinders »

milwiron wrote: Mon Feb 20, 2023 3:13 pm With the horrendous cost of brass it's time for me to start considering building a tender out of steel sheet, possibly galvanized. I have worked a lot with stainless but it's hardly an economical alternative.
I've read through the archives and there doesn't appear to be a consensus on sealants. Any successes out there on a coat-and-forget modern sealant?
Please don't mention Phil Swift and Flex Seal, I've tried it around the house, it doesn't work well for anything.
Thanks much,
Denny
I built the tank on my shay out of galvanized and I sealed it with good old fashioned plumbing soldered. It cant flake off or let water get behind it, and with good flux it will wick into the joint and help structurally as well. I did have to clean and redo a few spots after burning the flux but it was a fairly easy job.
If I had to do it again I would use that method again without hesitation.
-Tristan

Projects
-2.5" scale Class A 20 Ton Shay

Steam Siphon: https://www.shapeways.com/shops/leavitt ... tive-works
Glenn Brooks
Posts: 2930
Joined: Mon Nov 10, 2014 1:39 pm
Location: Woodinville, Washington

Re: Sheet steel tender tank sealant

Post by Glenn Brooks »

The big question is: how long do you want the tank to last? Almost every coating is water soluble to some degree. The sealers that last the least are ones that are designed to occasionally repel water from external surfaces. So look for a coating (or actual seam sealer) that is made for 100% submersion. Once you protect the surface of the tank, with an impervious primer and topcoat for longevity,all you need do is make sure any and all seams and inspection plates are water tight. I personally prefer marine seam sealers, such as Dolphinite to seal inspection plates and lap joints that are are bolted or riveted.

Glenn
Moderator - Grand Scale Forum

Motive power : 1902 A.S.Campbell 4-4-0 American - 12 5/8" gauge, 1955 Ottaway 4-4-0 American 12" gauge

Ahaha, Retirement: the good life - drifting endlessly on a Sea of projects....
User avatar
Greg_Lewis
Posts: 3014
Joined: Wed Jan 15, 2003 2:44 pm
Location: Fresno, CA

Re: Sheet steel tender tank sealant

Post by Greg_Lewis »

I think Jack Bodenmann has said that he makes an inner tank out of PVC or some similar plastic. The advantage of that is that you can do whatever you want with the outer tank for aesthetics and not worry. The plastic is easy to work with and will last forever.
Greg Lewis, Prop.
Eyeball Engineering — Home of the dull toolbit.
Our motto: "That looks about right."
Celebrating 35 years of turning perfectly good metal into bits of useless scrap.
User avatar
Dick_Morris
Posts: 2841
Joined: Sat Jan 04, 2003 2:09 pm
Location: Anchorage, AK

Re: Sheet steel tender tank sealant

Post by Dick_Morris »

I have worked a lot with stainless but it's hardly an economical alternative.
I have the front of a stainless steel fridge that I saved when the fridge failed. I think it will be adequate for tender sides and possibly the top and bottom if I use some care with internal supports/baffles. Dishwasher fronts are another source of SS sheet.
FKreider
Posts: 338
Joined: Fri Feb 02, 2018 8:44 pm
Location: Massachusetts

Re: Sheet steel tender tank sealant

Post by FKreider »

Last year I thought I would save some time by using marine sealant on my (brass) tender body. I followed the directions with regards to cleaning the surfaces and waiting the appropriate amount of time for it to dry before putting in any water. It leaked like a sieve and I spent the next couple of weeks with an assortment of scrapers, wire brushes and flat head screwdrivers removing the nasty stuff from the tank!!

After I finished scraping ALL of the gunk off I then soft soldered the whole thing and now its perfectly water tight. Next time I will go right to soldering and save a lot of time and frustration.

P.S. I cant remember which marine sealant that I used but it was available at the big box stores, in my case Home Depot.
-Frank K.
User avatar
Bill Shields
Posts: 10460
Joined: Fri Dec 21, 2007 4:57 am
Location: 39.367, -75.765
Contact:

Re: Sheet steel tender tank sealant

Post by Bill Shields »

Devcon flexane.

Clean and prime and paint it in.

Prep with fine carbide blasting #80 grit) and prime with the two recommend primers

you cannot tear it off the brass...gotta cut it off with a razor blade....or blast it off with the grit.


Lifetime solution...don't care how long you live.

I have a brass tender I did 40 years ago that is still tight. A steel tender done 20 years ago.
20220726_172932.jpg
20220726_172932.jpg (98.35 KiB) Viewed 2214 times
Because it is two parts you do not have to worry about drying...you can also paint more on if you have a leak.

Ain't cheap, but you get what you pay for.
Attachments
20220726_172922.jpg
20220726_172922.jpg (96.72 KiB) Viewed 2214 times
Last edited by Bill Shields on Tue Feb 21, 2023 12:28 pm, edited 1 time in total.
Too many things going on to bother listing them.
Pontiacguy1
Posts: 1566
Joined: Thu Apr 26, 2012 10:15 am
Location: Tennessee, USA

Re: Sheet steel tender tank sealant

Post by Pontiacguy1 »

One of the most important things to making a tender last, in my opinion, is having a way to be able to completely drain all the water out of it. I have started putting a low spot right in the middle of my tender tank floors. Sometimes two spots if it is a bigger tender. I basically took a 6" piece of pipe, set the tank on it, and then used a rubber mallet to beat the floor down inside of it so that it was about 1/4" lower in the middle than the surrounding floor. I made sure my small depression would fit in between the tender frame rails. I then silver soldered a 1/4" fitting I made into the bottom of that depression, and drilled it through into the tank. Now, a simple valve or petcock will drain the tender tank very well. I then leave it open and try to get as much out as I can while I'm prepping to load. A lot of people drain their tenders through the valves that go to the locomotive, and most of those will leave about 3 /16" to 1/4" of water standing on the floor of the tank. Like a boiler, just getting it dried out after use will extend its life tremendously, so put some thought into how to easily and completely drain it.
hoppercar
Posts: 616
Joined: Sun Jul 22, 2018 4:09 pm

Re: Sheet steel tender tank sealant

Post by hoppercar »

I have always built my tenders from brass, regardless of the cost....after fitting, riveting and soldering....you will have a lifetime tender...with no need for glues and goos, that eventually leak, and are in constant need of repairs
User avatar
gwrdriver
Posts: 3439
Joined: Mon Jan 06, 2003 10:31 am
Location: Nashville Tennessee

Re: Sheet steel tender tank sealant

Post by gwrdriver »

Some years ago, when looking to find the latest & greatest sealant for a tender tank, a chum suggested I look into what the auto and motorcycle restorers were using to seal their gas tanks. He figured they would always know what the latest & greatest was.
GWRdriver
Nashville TN
Post Reply