Olfelt

[Mike Rometer]

If the wood is ply then the oil could destroy the glue. I've seen it with some plys.

Not what you wanted to hear I'm sure.

[DetroiTug]

Quote: "cut back two layers of laminations and it's still oil soaked"

Yea that's not good. Coincidentally, I ran in to the same problem recently. I'm restoring a 1900 Conrad steam car with a wood body. One side of the body inside was soaked with oil probably from engine exhaust. 115 year old oil to be exact and it was still oily. I had the side off the vehicle and laid it flat, then I covered the area with oil dry and left it for a few days. and kept sweeping it around over the area to rearrange the contact points of the grains to the oil. It dried it out pretty good, it still dark looking, but it's not oily anymore. Not sure how well it will hold Epoxy seal coat.

Seems as though mineral spirits would mix with the oil and evaporate, but I haven't tried that. I don't think oil and acetone will mix - maybe they do.

-Ron

[RGSP]

Acetone is not bad as a grease solvent, but trichlorethylene is better (if you can get it), and methylene chloride is cheaper and is sometimes slightly more effective. None of these should significantly affect the phenolic adhesives used in marine ply and good grade exterior ply (except for temporary softening), though some cheap plys will literally fall apart after trichlorethylene (via bitter experience), though of course hot water would be just as destructive.

[TahoeSteam]

So, Ron's boiler is FINALLY in! We had to wait till almost noon for it to "warm up" and once we got out there it went so well we had time for a lovely walk and tour of the neighborhood! Thank you Ron and Roxanne for the great food and your wonderful hospitality... AND putting up with us! Hope you're staying dry!

[DetroiTug]

Planning to do the same to the tug. I'm sold on Ofeldts. My buddy builds them with copper coils and they do just fine - gasoline fired. Brazes the copper to steel nipples in the center drum.

He came up with a new boiler design based on the Ofeldt, so far, so good. It results in a square boiler, would be great for a steam bike. Two sets of high and low headers that the coils connect to.

PS I know that head is not fitted correctly to that drum and he and I go around and around about it.


-Ron

[TahoeSteam]

Your friend's boiler looks similar to a Blackstaffe Boiler, but with a vertical drum.

After looking a the great job Ron as done on his boiler, I'm determined to build one for my dad's launch "George H. Sandin" to replace the existing Semple VFT40

[Lopez Mike]

I find those photos terrifying. I can't imagine doing any repairs. I sometimes think of a water tube boiler as a future replacement for my VFT if it ever comes to that but the complexity is very daunting.

To quote Captain Ball in one of the Glencannon episodes, it's a enough to give you, ". . . the wahwahs complete!"

[DetroiTug]

Quote: "I can't imagine doing any repairs."

That brings up a great topic and not one I've seen discussed here. I keep reading about retubing a VFT and it's always skimmed over as not being a big issue. I've never had to do it yet, but I have to believe getting a rusty crusty tube out through a hole in a crown sheet that is sized within a few thousandths to what the tube was when it was new, would not be easy. In my VFT like many others, the tubes are welded in, which means a large chamfer tool would need to be used to cut out the old weld and retaper the hole.

I think a water tube would be much easier to replace. I've never done either repair so I'm assuming and simply basing it off other projects I've done of similar nature. Those tubes gotta be difficult to get out. In Locomotive boilers - watching the old British transport films of retubing Locomotives, those tubes had a swaged/enlarged diameter on each end, which would help greatly upon removal. All the hobby boilers I've seen use constant diameter flues/tubing.

What's the trick here or is it just a lot of drilling torching and pulling? I can see slitting the tube with an acetylene torch and collapsing it as it comes out, but what a pain that must be especially when there are 50 or 60 of them. Probably less work to build another boiler.

-Ron

[fredrosse]

"I have to believe getting a rusty crusty tube out through a hole in a crown sheet that is sized within a few thousandths to what the tube was when it was new, would not be easy. "

Removing old boiler tubes is difficult, often requiring the tube to be collapsed within the boiler shell, very difficult. For our small sized firetube boilers there are some options that can work well:

Solvent wash the boiler interior to remove all oil/grease if there is any, often found on systems where engine oil found its way into the feed pump. Flush out all scale, etc. Mask any screw threads on the boiler with iron (or plastic) plugs and pipe dope.

Acid clean the boiler interior, with concentrated Hydrochloric acid. This is sold at all swimming pool supply houses for a couple of $ per gallon. After about 1 hour, all rust will be GONE from the interior of the boiler. Wash out thoroughly, with a strong alkaline solution, I use tri-sodium phosphate to neutralize the acid, and there are several other cheap chemicals that will also work well.

Drill, then ream the tube ID to the original tube hole reamed diameter, to the depth of the tubesheet, this removes the expanded portion of the tube without damaging the tubesheet.

Slide the old tubes out.

Please note that this path is wrought with potential danger, and safety procedures must be followed. Also environmental considerations are relevant, and environmental compliance regarding discharge of wastewater must be considered. If steel is left in the strong acid overnight, the tubes may be completely dissolved. During this process the boiler shell will also experience thinning. Removing all rust and and a few thousanths of steel is OK for most shells, removing 1/8 if an inch (3mm) is not OK!

If the tubes are seal welded into the tubesheet, then this weld must also be machined out, and with proper previous fabrication, the tubesheet holes will still have a good amount of unwelded surface for rolling in the new tubes.

[Ethelred]

Why is it most VFT boiler tubes are welded in and not just expanded?
It would make replacement much easier.