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(DIR) Return to: Restorations
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#Post#: 53107--------------------------------------------------
Look Ma, No Heater: Restoring a B31 with no "Fire in the Be
lly"
By: Paula Date: September 12, 2022, 1:38 pm
---------------------------------------------------------
After restoring the Quality Brand (Empire) B30 horizontal
engine, I began to fancy a B31 vertical engine. Though different
in configuration, these two models share many of the same parts.
About a year ago, a nice B31 came up on eBay, and it appeared to
be pretty much intact, requiring very little effort to make it
like new:
[attachimg=1]
All the parts seemed to be there, even the normally busted-off
whistle topper. The stack had a hole drilled through it, no
doubt to insert a pin or rod for added torque when the thread
seized. No matter, I already had a nice original to replace it
with.
[attachimg=2]
I should have paid closer attention to the following picture, as
it gave a clue as to a problem I would only discover later:
[attachimg=3]
Notice the dark discoloration towards the rear of the base? This
should have been my cue to ask the seller to post a picture of
the bottom of the engine. Trusting soul that I am, this didn't
even occur to me. I figured that an engine that nice, should
probably still have a working heater. Even so, the seller's
description included the words, "Untested, no clue if complete,
selling as is, no refunds." That didn't faze me none, and I
proceeded to turn in the high bid.
Imagine my disappointment when I received the engine only to
discover that it was completely naked below the base: no bottom
cover, no heater, no heater clamp, no nothin'! The terminal pins
were still there, as could be seen from the top side, but
everything past that point was AWOL. I felt like an idiot for
not having been more diligent about evaluating the engine's
condition before bidding. I could have contacted the seller, and
probably should have, but he was very clear in stating his terms
of the sale. I doubt he had any clue about it either way. I
needed to own my negligence, suck it up, and move on. Besides, I
had an idea of how to solve the problem, and it could even turn
out to be a fun challenge.
I disassembled the engine to begin the restoration process. You
can see from this bottom view of the base, that the heater must
have died a violent death:
[attachimg=4]
...though not as obvious from the top side:
[attachimg=5]
Nevertheless, the base got a good blasting to remove all traces
of the heater's spectacular demise. I also blasted the engine
frame:
[attachimg=6]
I needed to replace the missing bottom cover, so I cut a piece
of stainless sheet metal to size and spotted and drilled a
couple of holes for the screws:
[attachimg=7]
[attachimg=8]
So far, so good. Next: Paint for the base and engine frame. Stay
tuned! :D
Paula
#Post#: 53134--------------------------------------------------
Re: Look Ma, No Heater: Restoring a B31 with no "Fire in th
e Belly"
By: Paula Date: September 13, 2022, 8:39 am
---------------------------------------------------------
Moving on...
Once the base and engine frame were blasted, I sprayed on
several coats of hi-temp primer. When that dried, I wet-sanded
down some of the high spots, and sprayed several coats of red
engine paint. I used Rustoleum, since I had some left from the
last project, though I'm not exactly in love with the stuff. It
takes forever to dry, and loses some of its gloss over time. The
shine can be brought back with polishing compound, but it
shouldn't be that way. Will try the Krylon next time. Here's how
the base turned out, after mounting the heater terminals, etc.:
[attachimg=1]
[attachimg=2]
Before painting the engine frame, I took the time to counterbore
the mounting faces for the various steam connection points for
o-rings. I like to do this just to eliminate hassling with
gaskets, which often don't seal very well, and even if they do,
if you take it apart, they may not seal when you put it back
together. Here's what it looked like after painting:
[attachimg=3]
[attachimg=4]
While the base and frame were drying, I turned to cleaning and
polishing the various parts as needed. The plating on this
engine wasn't bad at all. A few worn spots here and there, but
well into the "acceptable" range. Here is what the finished lot
looked like before any polishing or painting:
[attachimg=5]
I wanted to make a new boiler sight glass, so I purchased some
1/4" O.D. borosilicate glass tubing off of eBay. I usually file
a small notch with a triangular needle file where I need to
break it, and it usually breaks pretty cleanly. If not, it can
be trued up on the belt sander. Make sure the length is long
enough to go well beyond where the seals will be, but not so
long that you can't angle the tube into the fittings. I have
found that 1/4" ID x 3/8" OD o-rings make a reliable seal for
the 1/4" dia. tubing. You need at least 2 rings at each end to
get sufficient sealing pressure:
[attachimg=6]
[attachimg=7]
I have found that the 2 threaded joints where the sight glass
fitting attaches to the boiler are best sealed with Loctite 542
(It's a brownish liquid.) Be sure to let is set up for 24 hours
before steaming.
(To be continued)
#Post#: 53143--------------------------------------------------
Re: Look Ma, No Heater: Restoring a B31 with no "Fire in th
e Belly"
By: RichSteamTx Date: September 13, 2022, 10:44 am
---------------------------------------------------------
[member=538]Paula[/member] , you do SUCH a better job than me, I
haven't the proper tools or the patience. I love your little
power insulators you make, I'd wished I could make those (saw
that in a different posting of yours). And you idea on the
"counterbore the mounting faces" what a great idea and you are
spot on about the gaskets. I have gone though a number of
different types and don't like any of them. I more or less have
given up finding a perfect fit.
#Post#: 53148--------------------------------------------------
Re: Look Ma, No Heater: Restoring a B31 with no "Fire in th
e Belly"
By: Paula Date: September 13, 2022, 1:23 pm
---------------------------------------------------------
Thanks for the kind words. I've been doing this kind of work for
a long time, so I've accumulated a lot of tricks and tools.
On the insulators, I've lately gotten away from the Garolite G-7
material, in favor of PTFE (Teflon). The G-7 material is
brittle, weak, and abrasive, and has a maximum temperature of
425 degrees. The PTFE is non-brittle, abrasion resistant,
machines beautifully, and has a max temp of 500 degrees. It's
also good for making hi-temp seals, like sealing washers for
boiler caps.
#Post#: 53189--------------------------------------------------
Re: Look Ma, No Heater: Restoring a B31 with no "Fire in th
e Belly"
By: Paula Date: September 15, 2022, 4:45 pm
---------------------------------------------------------
Replacing the Original Heater
In my day job, we frequently work with cartridge heaters, both
for hot-melt glue application, and 3D printers. So, being
somewhat familiar with their ins and outs, I decided to try
cartridge heaters to replace the missing B31 heater unit. Mind
you, this was long before the recent solutions had been worked
out, namely improvising the 35MM Chinese band heater, or simply
winding a new heater with nichrome wire, as pioneered by
Junkologist (Mike). In my case, even with those approaches, I
would have to come up with a way to hold the heater in place,
since my engine didn't even have the internal expanding clamp.
Given all that, I went ahead with designing a cartridge heater
solution. It turns out that cartridge heaters are not all that
well-suited to this application. The only length that will fit
is a 1" long heater, and the largest diameter in this length is
3/8 inches, which is rated at only 150 watts. If I used two of
them (300 watts), this would be somewhat less than the 350 watts
of the original heater. If I used three of the 150 watt heaters,
I would be well above the original rating at 450 watts. I was a
bit leery of exceeding the nameplate wattage, even if
performance might suffer as a result. As it turned out, I wish I
had went with the three heaters.
Here is one the heaters that I purchased. It's a Tutco #CH15766,
rated at 150 watts, 120 volts:
[attachimg=1]
Due to the cramped quarters beneath the boiler, I would need to
bend the heater's leads at a sharp right angle. To be able to
see what I was doing, I decided to remove the factory-installed
hi-temp sleeving. Here's what the heater looks like with the
sleeving removed, and the heater wires bent:
[attachimg=2]
I used some PTFE heat-shrink tubing to re-insulate the heater
wires where the bends were made. I then dressed the leads to
length, and crimped some ring terminals to the wires. Here is
the cartridge heater pair, ready for installation:
[attachimg=3]
For best performance and life, cartridge heaters should be
installed in a close-fitting hole, preferably in a aluminum
block which can conduct the heat efficiently to the target
medium (in this case, the boiler sheath, and the water within.)
I decided to make an aluminum plug to fit the I.D. of the
opening in the bottom of the boiler. It would be split into two
parts, each with a reamed hole for a heater cartridge. A set
screw between the plug halves would force the two halves firmly
against the sides of the opening.
Here is a what the plug looks like after turning to size on the
lathe:
[attachimg=4]
A rear-mounted parting tool was used to cut off the plug:
[attachimg=5]
Reaming the drilled holes to size for the heaters:
[attachimg=6]
A set screw hole was tapped using a 5/16-18 taper tap:
[attachimg=7]
I clamped the plug to the bed of my cutoff saw to split it down
the middle:
[attachimg=8]
Here is the finished plug assembly and heaters, ready for
installation:
[attachimg=9]
(Stay tuned for more...)
#Post#: 53196--------------------------------------------------
Re: Look Ma, No Heater: Restoring a B31 with no "Fire in th
e Belly"
By: St Paul Steam Date: September 15, 2022, 9:12 pm
---------------------------------------------------------
Lots of nice machining there Paula ,interesting approach to the
burnt out/missing heaters for these units.
#Post#: 53198--------------------------------------------------
Re: Look Ma, No Heater: Restoring a B31 with no "Fire in th
e Belly"
By: RichSteamTx Date: September 15, 2022, 9:27 pm
---------------------------------------------------------
Wow - lookie there - who needs Chinese crap when you have an
American Machinist! Sooooo jealous! I literally been day
dreaming about equipment like that... though even if someone
dropped one off on my driveway I wouldn't know how to operate
it!
I am not surprised the two 150w guys didn't give you enough. I
assume v2 of the heater is coming with 3 cartridge heaters? I
am so excited to see that!
#Post#: 53200--------------------------------------------------
Re: Look Ma, No Heater: Restoring a B31 with no "Fire in th
e Belly"
By: Paula Date: September 16, 2022, 9:14 am
---------------------------------------------------------
[quote author=St Paul Steam link=topic=5906.msg53196#msg53196
date=1663294328]
Lots of nice machining there Paula ,interesting approach to the
burnt out/missing heaters for these units.
[/quote]
[quote author=RichSteamTx link=topic=5906.msg53198#msg53198
date=1663295274]
Wow - lookie there - who needs Chinese crap when you have an
American Machinist! Sooooo jealous! I literally been day
dreaming about equipment like that... though even if someone
dropped one off on my driveway I wouldn't know how to operate
it!
I am not surprised the two 150w guys didn't give you enough. I
assume v2 of the heater is coming with 3 cartridge heaters? I
am so excited to see that!
[/quote]
Thanks for the acknowledgement, guys! I suppose the question of
what is "enough" is an open one. I will wait and see how this
one performs under load before deciding. Going to a 3-heater
design wouldn't be that difficult -- I already have an extra
cartridge -- I would just need to make a 3-segment plug. We'll
see how it goes. If she starts up and runs halfway decent, I may
call it good enough. It's had a hard life, and maybe deserves an
easy retirement! ;D (I know I do!)
#Post#: 53238--------------------------------------------------
Re: Look Ma, No Heater: Restoring a B31 with no "Fire in th
e Belly"
By: Paula Date: September 19, 2022, 9:56 pm
---------------------------------------------------------
Ok, let's wind this up...
Just before assembling the B31, I managed to get all the parts
together in one place for a "group shot":
[attachimg=1]
Everything went together pretty easily. I installed the 2
cartridge heaters in the bottom of the boiler, using some boron
nitride paste on the heaters and the plug. Here's what it looked
like with the heaters installed:
[attachimg=2]
I cut out a piece of insulation for the bottom of the heater
plug... :
[attachimg=3]
...and a thicker piece to go between the heaters and the bottom
plate:
[attachimg=4]
Here are some pictures of the finished engine (I added a small
pressure gauge at the last minute):
[attachimg=5]
[attachimg=6]
[attachimg=7]
As I suspected, the performance of the finished engine is not
exactly overwhelming. It works, but it's kind of like me... only
able to go flat out for less than a minute. :-\
Here's a short video of it pulling a modest load (for a modest
amount of time!):
(HTM) https://youtu.be/rS1XtWbZ3E8
I think this engine could definitely benefit from a third 150
watt cartridge heater. I haven't decided yet if I'm going to add
a third heater, but I will most certainly use three heaters on
any future applications of this type.
Thanks for watching! :D
#Post#: 53239--------------------------------------------------
Re: Look Ma, No Heater: Restoring a B31 with no "Fire in th
e Belly"
By: RichSteamTx Date: September 19, 2022, 10:22 pm
---------------------------------------------------------
I'd say she is running pretty good and she looks good doing it!
So darn shiny and new looking - fablous!
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