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The Regular Stuff: Chat, Buy, Sell, Off Topic, etc. => General Discussion - Model & Toy Steam Engines – Stirling Cycle – Flame Lickers – Small Antique Originals => Topic started by: RedRyder on February 28, 2026, 03:26:13 pm

Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: Jim on March 01, 2026, 05:05:40 pm
Good luck with it Gil
Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: RedRyder on March 01, 2026, 03:33:45 pm
A stirling cycle engine like this experiences very low pressure and vacuum

Extreme Heat JB Weld will withstand up to 800 PSI if properly applied and cured..
Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: komet163b on March 01, 2026, 02:38:49 pm
  Provided the area sealed by the JB is not under pressure it just might work.
Fingers crossed!

  I used the Hi Temp JB on the leaky bottom of a Weeden 'steel boiler' pumper
engine.  It was just building pressure when it started leaking again. 
I run it on air, now.

  On a personal note...
  Steel boilers on toy engines.  What were the designers and managers of Weeden,
Marx, and Ind-X engines/boilers thinking!  Probably bending the knee to the penny
pinching accountants.  God saves us!

Good Luck,
Wayne
Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: RedRyder on March 01, 2026, 01:43:03 pm
I agree getting someone to weld or braze is the right move.

However I am first trying a simpler fix.

I have applied Extreme Heat JB Weld which is rated for 1,000 degrees F continuous and up to 2,000 F for short durations.

In addition it will be easy enough to grind it away if it doesn't work well.

Gil


[attachimg=1]
Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: Fullraceflathead on March 01, 2026, 12:54:51 pm
Welding does take practice but you'll definitely get the hang of it with time but looking at what you're trying to weld I personally would pay somebody to tig weld it I would imagine that could be welded for probably 50 bucks somebody that's a tig welder with experience it'll look beautiful when it's done.
Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: Stoker on March 01, 2026, 08:14:40 am
Not up to speed with a TIG welder, I have a MIG welder that's takes either gas or gasless wire and it works 110% better using gas and I can weld pretty thin material ie car body.

I would be brazing that though Gil.

By the look of the price of the item, I'd personally take it to a couple of metal fabricator shops and see what they say and get a pro to do the job.

Think I'd have to agree with Jim on this one .... looking into professional service might well be the best idea for such a job!
Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: cheepo45 on March 01, 2026, 08:14:29 am
With the various other materials on that, it may be easier to fabricate a new part.
The old solder, etc. will contaminate the area and you will never get good adhesion.
 Scott
Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: Jim on February 28, 2026, 11:50:47 pm
Not up to speed with a TIG welder, I have a MIG welder that's takes either gas or gasless wire and it works 110% better using gas and I can weld pretty thin material ie car body.

I would be brazing that though Gil.

By the look of the price of the item, I'd personally take it to a couple of metal fabricator shops and see what they say and get a pro to do the job.
Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: Stoker on February 28, 2026, 10:55:40 pm
Well, there is different types of brazing. I was thinking of brazing with a brass or bronze brazing rod and borax flux, though a good silver braze should be fine and may even be better. I don't really know which has the higher temperature tolerance but suppose that would be easy to look up?!?!
Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: RedRyder on February 28, 2026, 09:34:32 pm
Thanks, Daniel. I think it was originally brazed an I tried to put some silver solder on it but it didn't take well.
Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: Stoker on February 28, 2026, 07:59:00 pm
Looks like someone has tried to solder that, which will need to be scrupulously cleaned off before attempting any further repair.

Think I would consider brazing instead of welding on that situation.
Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: RedRyder on February 28, 2026, 07:40:53 pm
I need to weld here

[attachimg=1]




For this engine

[attachimg=2]
Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: RedRyder on February 28, 2026, 07:24:53 pm
I agree.

I need to get good enough to lay a bead over about 1.5" to repair the heated end of a Stirling Cycle engine.

Picture coming.
Title: Re: Need To Weld to Repair a Stirling Cycle Engine
Post by: cl350rr on February 28, 2026, 04:25:33 pm
On thin material like that it might be better to do a series of spot welds rather than try to run a continuous bead.
Title: Need To Weld to Repair a Stirling Cycle Engine
Post by: RedRyder on February 28, 2026, 03:26:13 pm
I got a very basic 120 volt Tig welder 125 amp from Harbor Freight called the Titanium 125.

It doesn't require an inert gas but uses .030" flux core wire.

I thought I would practice on some unimportant steel to get the hang of it.

I watched a couple videos and after the first to attempts (pictures below) I am convinced that good welds require training and experience.

Here are the welder and my first 2 attempts:

[attachimg=1]

[attachimg=2]

[attachimg=3]

[attachimg=4]

[attachimg=5]