# Smoke box insulation?



## Jim Schulz (Aug 10, 2009)

I'd like to insulate an Accucraft Legend 4-4-0 smoke box. Suggestions on what I should get, from where, and what to expect to pay?


----------



## zubi (May 14, 2009)

Jim, use ceramic sheet. It is not very expensive, I guess most live steam dealers in the US should be able to supply it. In the UK, David Bailey sells square foot for 3.50 GBP, in Japan you can get it from Aster for 1600 yen. Best, Zubi


----------



## Charles (Jan 2, 2008)

Jim
You can get the insulation at a good price from McMaster Carr

McMaster-Carr


----------



## thumper (Jan 31, 2009)

Here in the U.S. you can buy Ceramic paper in several thicknesses starting at about $2.50 per square foot from almost any stained glass manufacturing studio. It withstands the heat of molten glass, can be folded, layered, cut with scisors and it is flexible like regular paper. It's great for lining the inside of smoke boxes and the outside of boilers! My source is:

Custom Stained Glass
14755 Northline Rd.
Southgate, MI 48195
Phone: 734.281.1511

http://www.csgstore.com/contact-cus...-glass.htm

You may be able to find a studio in your area so you can check out the various types.

Good luck,

Will


----------



## Jim Schulz (Aug 10, 2009)

Remind me again why I would want to insulate the entire smoke box? I've got front insulated to better protect a new number plate (see photo), but what about the interior walls? How will this improve performance? I'm hoping that it will eliminate or reduce the snapping and popping of burnt steam oil. Is that right? As you can see in the second photo, there are openings on either side of the smoke box saddle where the steam lines connect to each steam chest. It is there that oily condensate pools and as it heats up snap, crackles, and pops, spattering hot water/oil on passers-by.


----------



## David Leech (Dec 9, 2008)

Jim, 
I hate to point out the obvious, but it would appear that whilst you have added insulation to the front, the brass screw is not protected, so it will transfer the heat to your number plate, and to the smokebox door anyway, making it not do what you hope. 
Likewise the outer ring of the door will feel the full effect of the burner heat, so everything will heat up. 
I would try and lay in another piece of insulation the full width of the door, over the screw, with just the wings of the brass clip poking through a couple of slots. 
Still not perfect insulation for the number plate, but better. 
All the best, 
David Leech, Delta, Canada


----------



## Jim Schulz (Aug 10, 2009)

Hi David, my Forney number plate is set up in a similar way (screw, JB Welded number plate, insulation under brass plate) and has held together so far. I was hoping this would hold true for the Legend as well. Will insulating the smoke box walls reduce the popping condensate?


----------



## HMeinhold (Jan 2, 2008)

A classic insulation material, which is also cheaper than the stuff from McMaster is fibrefrax: 

http://www.aircraftspruce.com/catalog/appages/fiberfrax.php 

Regards


----------



## Jim Schulz (Aug 10, 2009)

I got mine from a local stained glass studio.


----------



## David Leech (Dec 9, 2008)

Jim, 
I know very little about GAS fired locos. 
Is there no exhaust pipe on this loco? 
Obviously the metal of the smoke box will get very hot. 
If the steam from the exhaust is allowed to condense and fall onto the hot metal it will spit and pop. 
Covering the metal with insulation should help - perhaps. 
It will certainly protect the outside of the smokebox from heat. 
Not sure that I can add any more. 
All the best, 
David Leech, Delta, Canada


----------



## Jim Schulz (Aug 10, 2009)

The exhaust pipe extends into the large part of the smoke stack, blowing most of the exhaust out of the stack. However, there is still some condensate making its way back into the smoke box. I would think that adding insulation can't hurt. I suppose I'll just do it, then see if it improves performance. I'm hoping that by having opened a bigger hole in the bottom and to the back of the smoke box will allow better drainage of condensate to the back and away from the hot steam lines, which are on the outside of the smoke box and uncovered between it and the steam chests. Perhaps I could wrap those steam lines in insulation...


----------



## Jim Schulz (Aug 10, 2009)

I think I'll pass on insulating the entire smoke box. It looks like opening a bigger hole in the bottom of the smoke box did the trick for drainage of the condensate. There's no more "snap, crackle and pop" of hot, oily water; the number plate stays firmly in place with the JB Weld; and the G-Scale Graphics printed vinyl transfer "278" holds fast and firm.


----------



## trainmax (Feb 16, 2008)

You should look at installing a Barkbox No more snap, crackles, and pops, spattering hot water and or oil on passers-by


----------



## Jim Schulz (Aug 10, 2009)

I tried a Summerlands Chuffer (Ruby version, which fits the Accucraft Forney), but I think it closed off too much air to the burner because it kept going out. Maybe now that I've got a bigger hole in the bottom of the smoke box that won't be an issue. I also tried the original exhaust pipe from the Forney, which is crimped on the top and blows out the side and into the smoke stack, but the problem I think was that it made more condensate drip down the stack and pool in the area between the smoke box saddle and steam chests, heating up to the snap, crackle, and pop. Again, now that there's a bigger hole in the bottom of the smoke box, which solved the problem with the original Legend exhaust pipe.... I've got some more experimenting to do.


----------

