Back to Steam

[steamboatmodel]

I am really impressed with how well this citric acid works as a pickling solution for cleaning up parts that have been silver soldered together. I had tried mixtures of vinegar and hydrogen peroxide before (as recommended by somebody on one of the forums) but it didn't seem to be very effective. Now I'm wondering about something else--I see that builders of model steam engines don't seen to use flux on their parts which they are silver soldering together. Instead they soak the items being soldered in a pickling solution before they silver solder them, and don't appear to be using any flux. I have always used flux on the parts I am going to silver solder. Who can shed a bit of light on this subject?

I have been silver soldering since I started in high school in 1964 and have always used flux, sometimes just borax but my preference is Tenacity 5. Currently I have WOLVERINE ULTRAFLUX which I picked up at a welding supply, It is not as good as Tenacity. Harris also makes a good flux.
http://www.harrisproductsgroup.com/en/Expert-Advice/tech-tips/silver-brazing-flux.aspx
Regards,
Gerald.

[Brian Rupnow]

No work on this project for a couple of days. I have a severe case of Sciatica and the pain in my lower back keeps me from standing at my machines. Fortunately it doesn't bother me when I'm setting down, so I can still do cad work. I did buy material for the engine base, but haven't done anything with it yet. I am anxious to get the last stand finished and move on to machining the base.

[Ye-Ole Steam Dude]

Hope you get to feeling better real soon.

Thomas

[gbritnell]

Brian,
The biggest problem with the soldering/brazing job is that all the heat was being absorbed into the piece of bar stock.
You would have had an easier time cutting the trunk free and soldering it like that.
To do more machining you could have turned a recess into the end of a piece of stock that matched the trunk flange and clamped it with a couple of screws.
gbritnell

[Twizseven]

Brian,

I have watched a number of your inventive builds over the last couple of years and admire the way you develop solutions to the problems/issues that arise.

I had a wander round a charity bookshop today and came across a two volume set of books which I think would keep you entertained for hours.

The books are entitled:

Ingenious Mechanisms for Designers and Inventors. Volume 1 and 11. It is an American book copyrighted in 1930 by The Industrial Press of New York City. The copy I have dates from 1946 (Seventh edition).

Topic titles include,

Cams and their applications
Intermittent Motions
Tripping or Stop Mechanisms
Reversing Mechanisms
Overload Relief Mechanisms
Interlocking Devices
Reciprocating Mechanisms

and so on.

There are over 1000 pages in the two volumes.

I'm sure if you could find a copy over there you would find lots of new and interesting mechanisms you could possibly build.

Regards,

Colin

[Brian Rupnow]

I have a couple of books of that type. They are quite inspiring, and I have built a few of the mechanisms.---Brian

[Brian Rupnow]

Brian,
The biggest problem with the soldering/brazing job is that all the heat was being absorbed into the piece of bar stock.
You would have had an easier time cutting the trunk free and soldering it like that.
To do more machining you could have turned a recess into the end of a piece of stock that matched the trunk flange and clamped it with a couple of screws.
gbritnell

George--Thank you for the advise. I'm sure you are probably quite right. There were more things to do after the silver soldering that required the assembly to still be connected to the main round piece of bronze. I'm not entirely happy with the way it went, but all of the solder joints are quite sound, if lumpy. I will machine/file/sand away the lumpy silver solder and remember this lesson for next time. Thank you for stopping by and saying Hi. I consider you to be one of the masters in this small engine world, and I appreciate your help.---Brian

[Brian Rupnow]

And now we have two!! The second stand turned out a bit nicer than the first one, mainly due to using a larger torch tip when soldering the joints. Although my solder joints on the second piece I built were quite lumpy, I also had enough build up of solder that when I machined/filed/sanded away the solder I didn't want, I had very few "craters" left below the finished surface. These two stands were probably the most difficult pieces to build. I'm looking forward to machining the aluminum base in the coming week so that I have something to mount these two pieces on.

[Stuart]

Brian

I quick tip for you

if you want to keep your citric acid mix for later use ad One drop of household bleach to the bottle/container

this will keep it fresh

[crueby]

So two bases made. Are you going to build a pair like Jo usually does? Or make 3...?

[Brian Rupnow]

So two bases made. Are you going to build a pair like Jo usually does? Or make 3...?

Chris--Not really sure what you mean here. Those soldered assemblies are not bases. They both fit on a common base, which I haven't made yet.

[crueby]

So two bases made. Are you going to build a pair like Jo usually does? Or make 3...?

Chris--Not really sure what you mean here. Those soldered assemblies are not bases. They both fit on a common base, which I haven't made yet.

My goof, base was the wrong word. I had forgotten that this is a twin cylinder engine too. Too many paint fumes from the shop that day!!

[Jo]

So two bases made. Are you going to build a pair like Jo usually does? Or make 3...?

  I can see I am getting a bit of a reputation for parallel builds. The only engine that I have more than one of is the triple Orphans. The 5A and Swan are different (but in some ways the same  )

Most of my castings sets are singular from now on

Jo

(Did you spot the .... "most"  )

[paul gough]

Colin, (Twizseven), keep your eye out for Vol. 3 & 4, you will find them interesting as well, pic below. Regards Paul Gough.

[Brian Rupnow]

The base for this engine is going to be Ahhhh---Interesting. Nothing horribly complex, just a lot of milling and drilling. I am going to make a simple jig to hold the soldered "towers" in the correct position and mark thru with a transfer punch to establish the 8 tapped holes which hold the towers in place. I find it a bit strange that the pillow block bushings for the crankshaft are mounted 'upside down' to what I consider normal practice.  I still have not fully recover from the sciatica pain in my lower back, but at least I feel improved enough today to do a bit of CAD work. I was supposed to be working in my office on the other side of town today, but I phoned over and begged off for today.