A tender subject.....

View previous topic View next topic Go down

A tender subject.....

Post by DaveLathrop57 on Sun May 12, 2013 1:50 pm

The tender frame is in fairly good condition. The tank needs the bottom third replaced. The trucks need rebuilding. So, let's think about how to replace the bottom third of the tank, how to make the tank last longer once repaired and reinstalled, and potential roller bearing retrofits to the tender trucks. I'm not sure about the oil tank.....so there's more to come.

DaveLathrop57

Posts : 242
Join date : 2013-04-14
Location : North Carolina, USA

View user profile

Back to top Go down

Re: A tender subject.....

Post by Overmod on Sat May 18, 2013 8:51 pm

Waterjet or plasma cutting, then welding for the tank. That may be the approach for all the tankage, and things like the oil heat chambers, coils, etc.

Rollers on the tender will be different from those on the engine truck. I would do exactly what NS has done and go straight to modern freight-car journals complete with rotating caps -- cover 'em for 'historical appearance' when that is wanted.

We should decide eariy whether we want to provide 'assisted guiding' for the rear of the chassis, by providing an alternate pivot point that puts the truck further forward and designing a spherical-face Franklin-style buffer, etc.

Think about modern brake rigging for the tank, to help perfornamce of the independent. Modern slack adjusting, etc. Brake rigging hardpoints calculated to simplify shifting the truck position from 'stock' to 'performance' if that approach is used.

Is there budget for more advanced brake valve tech -- say even 26RL? I would be tempted to design this system to be "PTC-ready" -- it costs little more to fabricate it that way, and there are potential great benefits from taking that approach...;-}

Overmod

Posts : 110
Join date : 2013-05-17
Location : Memphis, Tennessee

View user profile

Back to top Go down

Re: A tender subject.....

Post by DaveLathrop57 on Sun May 19, 2013 11:11 am

Brake system covered in the brake section. 6ET is what we have and know. It's also already donated for the project.

Off the shelf conversion makes sense, and is an easy thing to ask for as a donation - no need to try to explain to a donor some odd custom idea. The tank itself....well, it's what you'd expect it to be - a steel frame with plate riveted on. The frame itself is in bad shpe, not only the plate....so, welding new steel on to the remaining top third of the tank, followed by the plate, followed by rivets for esthetic rather than mechanical benefit, followed by.....some sort of sealing / preservative coating? Such a coating must adhere not only to the new clean parts of the tank, but to the older top third as well.

Dave




DaveLathrop57

Posts : 242
Join date : 2013-04-14
Location : North Carolina, USA

View user profile

Back to top Go down

Re: A tender subject.....

Post by Overmod on Sun May 19, 2013 1:24 pm

If you have good welders -- are you dedicated to historical construction for the tender? Easy to make it a water-bottom, perhaps semi-monocoque, and just put ledger strips on the side to simulate the frame siderails...

There are good coatings -- didn't RyPN recently have a couple of threads about roof and bridge paint systems? -- but they are expensive. I would advocate using one of the two-part systems used for refurbishing vehicle fuel tanks, and arranging some way to tumble the tender body (as with the boiler for treatment) so that every part is coated. Preheat the thing to the equiivalent of rail neutral temperature to ensure the stuff flows into every little nook and cranny and won't develop seams or cracks in service?

I think I'd powdercoat the exterior, perhaps using very high voltage to ensure good contact of the resulting coat. Can you 'reflow' powdercoat with something like a glorified heat gun it if develops cracking?

Overmod

Posts : 110
Join date : 2013-05-17
Location : Memphis, Tennessee

View user profile

Back to top Go down

Re: A tender subject.....

Post by wilkinsdm on Fri May 24, 2013 11:11 am

If mainline access isn't an issue here, why rollers for the tender?

wilkinsdm

Posts : 5
Join date : 2013-05-17

View user profile

Back to top Go down

Re: A tender subject.....

Post by DaveLathrop57 on Fri May 24, 2013 12:50 pm

Elimination of maintenance when the time is ripe to eliminate it. This is probably the only heavy work the tender is likely to have peformed until something critical happens in the future....so why not make it as robust as possible while we can? The effort to tear down and replace bad seals in otherwise healthy trucks prevents a lot of bad seals from being addressed.

Dave

DaveLathrop57

Posts : 242
Join date : 2013-04-14
Location : North Carolina, USA

View user profile

Back to top Go down

Re: A tender subject.....

Post by Overmod on Fri May 24, 2013 2:10 pm

From comments made in a different thread here:

Might make sense to put a lining of some sort in the tank, for example one of the two-part systems used to fix auto gas tanks, or use one of the fiberglass systems used to make pools, adjusted for a high-vibration environment. That would preserve much of the original structure without risking lots of little leaks with rubber-washered screws in them...

I also wonder whether retrucking completely, rather than adapting the existing trucks to take roller-bearing wheelsets, might be a less expensive option -- seems to me that old boxcars can be bought cheap with perfectly serviceable bearings and wheelsets, and just changing the trucks over, modifying the springing if necessary, would get a number of jobs done with minimal expense...

Overmod

Posts : 110
Join date : 2013-05-17
Location : Memphis, Tennessee

View user profile

Back to top Go down

Re: A tender subject.....

Post by DaveLathrop57 on Fri May 24, 2013 2:51 pm

We've already been inside the tank with a fine tooth comb, and the most logical option is replacement of the bottom third (or was it two thirds) of the tank . The bottom sheet, lower parts of the side sheets, interior framing and bracing and buffers are badly deteriorated in the few places they are not actyually gone. There's really not enough there to try to repair. The coating was to fend off future deterioration as best we can.

Wayne did mention there may be roller bearing trucks off container flats with smaller diameter wheels that might work.

As Dave Dick indicated in the general information section this afternoon, the formal public part of the process is getting ready to start. Part of this will be forming a sort of troop of networkers to solicit specific in kind donations from regional industries and suppliers. Tank fabrication is certainly one of the items we should be able to find a supplier to do for us. There's no lack of fabricators in NC and at least one of them must like steam locomotives enough to help us out.

It will be interesting to see what condition the trucks are in once we get them out and torn down. We can take a more informed look at those options once we know that.

Dave

DaveLathrop57

Posts : 242
Join date : 2013-04-14
Location : North Carolina, USA

View user profile

Back to top Go down

Re: A tender subject.....

Post by Overmod on Fri May 24, 2013 3:12 pm

DaveLathrop57 wrote:
Wayne did mention there may be roller bearing trucks off container flats with smaller diameter wheels that might work.


My impression was that the stack cars have larger, rather than smaller, wheels. Perhaps some of the spine cars have low-wheel trucks, but again I'd think the added weight-carrying capacity would dictate larger wheels.

What I think he means is automobile carriers. Those can have very small wheels, as the load is relatively limited, and with the required bottom continuous deck, there are valid reasons to reduce vertical running-gear height as much as possible. In addition, the springing won't be as substantial as for artic cars, and probably has a lower rate and perhaps even added compliance to make the ride better for the automobiles...

If you can tolerate treads worn a little fine for interchange service, I'd bet you could get a pair of those trucks very cheaply, if not indeed donated (the donation value, tax-deductible, exceeding the scrap or "rebuildable-core" value of the trucks entirely). If you are going to convert the existing trucks, those wheelsets with bearings and boxes might be the thing to use -- if you don't mind modifying the box seats in the frames.


Overmod

Posts : 110
Join date : 2013-05-17
Location : Memphis, Tennessee

View user profile

Back to top Go down

Re: A tender subject.....

Post by wilkinsdm on Tue May 28, 2013 3:59 pm

Auto racks and 89' flat cars use 28" wheel sets, as opposed to 33" wheels which are standard.

I have the most recent Car and Locomotive Cyclopedia at home and will peruse for some dimensional data that may be of use.

wilkinsdm

Posts : 5
Join date : 2013-05-17

View user profile

Back to top Go down

Re: A tender subject.....

Post by DaveLathrop57 on Tue May 28, 2013 4:03 pm

The tender trucks are speced at 30" diameter wheels......with a 4.5X8 journal. I'm not sure how easy it would be to retrofit modern freight car roller bearing wheelsets made to replace at least a 5X9 journal.

Dave

DaveLathrop57

Posts : 242
Join date : 2013-04-14
Location : North Carolina, USA

View user profile

Back to top Go down

Re: A tender subject.....

Post by wilkinsdm on Tue May 28, 2013 4:06 pm

If you used modern trucks at worst, you'd have to replace the center plate on the tender. Not impossible. I imagine the brake rigging is shot as well.

wilkinsdm

Posts : 5
Join date : 2013-05-17

View user profile

Back to top Go down

Re: A tender subject.....

Post by Overmod on Tue May 28, 2013 4:22 pm

You need to measure the contact height on the existing trucks, and compare it to whatever modern equivalent you have. This should certainly be close to the height for a modern 28"-wheel truck. I don't know if there are many contemporary trucks that use 30" wheels.

If you wanted to replace the wheelsets alone, you would have to modify the truck frames. This is nontrivial considering the amount of material being removed. It will probably be better to replace the entire sideframe unless it's cast -- and perhaps even then.

If you cannot mill the recess larger, you'd be looking at fabricating new ends, or cutting them from an existing modern truck and machining them down to more prototypical appearance if necessary, and then welding them onto what you have. This is almost certainly more trouble than it's worth, and damages historical integrity (to say nothing of regulatory safety!) in the process.

I would go straight to 28" modern trucks, and modify what is on the truck bolster to fit the existing tender centerplates if that is practical.

My opinion is that full historical authenticity in brake rigging is not a major priority. Others may of course differ with that opinion. I would use components compatible with the new trucks for the linkage, and perhaps even use air-brake components from the 'donor' car, again modifying the components to fit the historical structure rather than vice versa.

Overmod

Posts : 110
Join date : 2013-05-17
Location : Memphis, Tennessee

View user profile

Back to top Go down

Re: A tender subject.....

Post by JJG Koopmans on Tue May 28, 2013 7:52 pm

Do you mind if I throw in my experience restoring historical trams?
Modifications should be applied in such way that they could be undone, reversible. So remove the old trucks, keep 'm intact in storage and modify the replacements in such a way that they fit the present tenderbody. Just don't destroy history!
Kind regards
Jos

JJG Koopmans

Posts : 62
Join date : 2013-05-17

View user profile

Back to top Go down

Re: A tender subject.....

Post by Overmod on Tue May 28, 2013 8:04 pm

JJG Koopmans wrote:
Modifications should be applied in such way that they could be undone, reversible. So remove the old trucks, keep 'm intact in storage and modify the replacements in such a way that they fit the present tender body. Just don't destroy history!

I could not agree more with this statement.

Overmod

Posts : 110
Join date : 2013-05-17
Location : Memphis, Tennessee

View user profile

Back to top Go down

Re: A tender subject.....

Post by DaveLathrop57 on Tue May 28, 2013 8:37 pm

We're not about destroying history, although we are the place where worn out centercabs go to die. This isn't about evil diesels, though......

I see a lot of merit in keeping the old trucks and adapting the center plates / side bearings / brake rods to fit new ones. I've done that work on other pieces before and it is an easy job compared to adapting the trucks themselves, and easily reverseable. Just looking at a couple photos of the new paint job and display site, and the cast truck frames are probably not an easy thing to adapt.

I think we could even retain the majority of the brake rigging by simply making new pull rods to fit the new trucks.

Dave

DaveLathrop57

Posts : 242
Join date : 2013-04-14
Location : North Carolina, USA

View user profile

Back to top Go down

Re: A tender subject.....

Post by Wayne Laepple on Tue May 28, 2013 9:29 pm

I have seen an engine that has smaller wheels on the truck closest to the engine. It looks a bit odd with the rear end noticeably higher than the tender apron. The question is whether 33-inch wheels are easier to turn down to provide 30-inch wheels, or does it make more sense to use 28-inch wheels and perhaps shim the center plate on the truck bolster and the side bearings. Personally, I'm inclined toward shims.

Wayne Laepple

Posts : 6
Join date : 2013-05-17

View user profile

Back to top Go down

Re: A tender subject.....

Post by Overmod on Tue May 28, 2013 10:18 pm

Wayne Laepple wrote:The question is whether 33-inch wheels are easier to turn down to provide 30-inch wheels, or does it make more sense to use 28-inch wheels and perhaps shim the center plate on the truck bolster and the side bearings. Personally, I'm inclined toward shims.

The thing to get, in this particular case, would be a set of 33" wheelsets nearing their wheel-wear limits but with good remaining bearing life. That would greatly reduce machining cost, and the anticipated further wheel wear to condemning limit would take a long time to develop in the anticipated service for this locomotive, I think.

Respringing will probably need to be done to get the trucks at proper ride height. This allows some further scope for adjustment of deck height, including with 28" trucks which may come very close to the actual desired #s when adjustment is made. I would advocate strongly that either the existing elliptic springs, or a set made to replicate their characteristics, be the approach actually taken, whatever the other truck components may be. (As noted, the new material would be adapted to fit the historical material...)

Overmod

Posts : 110
Join date : 2013-05-17
Location : Memphis, Tennessee

View user profile

Back to top Go down

Re: A tender subject.....

Post by Overmod on Fri Oct 04, 2013 6:43 am

Posted over on RyPN this morning was a reference to the following line of products:

http://www.cohesantmaterials.com/Products.aspx

This might be something to consider when approaching tender restoration, even though heavily relying on it would smack of a kludge...

There are probably other fully-waterproof coating systems, some of which might be better or less expensive. Here' at least, is a known source and a starting point for further research and consideration.

Overmod

Posts : 110
Join date : 2013-05-17
Location : Memphis, Tennessee

View user profile

Back to top Go down

Re: A tender subject.....

Post by DaveLathrop57 on Fri Oct 04, 2013 10:16 am

The current plan (subject to reconsideration as we forge ahead) is to replace the bottom third of the tank and repair the remainder. Certainly some form of interior protective coating would be desirable......when we get closer I think we will have to do some research and make a choice as to what product we need to use.

Dave

DaveLathrop57

Posts : 242
Join date : 2013-04-14
Location : North Carolina, USA

View user profile

Back to top Go down

Re: A tender subject.....

Post by st947spm on Fri Mar 28, 2014 8:43 am

I am fairly certain that I heard one of the truck drivers at one of our facilities talking about a spray on product that they do in-situ to tank trucks to coat them and protect them. It sounded very similar to the spray on truck bed liner process. Way may need to shot blast the inside of the tender to prep the surface but it may be an option. I will see if I can come up with some more details. It would probably save cost to have it done either where the repairs are made or right at our site vs. double shipping the tank.

A side note. I work for a company that makes glass blasting media (among other things). If we ever need to do any cleaning or surface prep, I am very certain I can get the necessary grades of material from our SMOG (slow moving off spec goods) for free.

st947spm

Posts : 4
Join date : 2013-05-17

View user profile

Back to top Go down

Re: A tender subject.....

Post by DaveLathrop57 on Fri Mar 28, 2014 5:51 pm

Never run out of need for blast media, thanks. I'll forward this to the project manager. Right now, efforts are pretty much devoted to the FRA annual and prep work for the opening of the season on April 12. 17 will be under steam all day, all are welcome.

Dave

DaveLathrop57

Posts : 242
Join date : 2013-04-14
Location : North Carolina, USA

View user profile

Back to top Go down

Re: A tender subject.....

Post by Sponsored content


Sponsored content


Back to top Go down

View previous topic View next topic Back to top

- Similar topics

 
Permissions in this forum:
You cannot reply to topics in this forum