Author Topic: Need To Weld to Repair a Stirling Cycle Engine (Read 174 times)

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:

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cl350rr · « **Reply #1 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.

RedRyder · « **Reply #2 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.

RedRyder · « **Reply #3 on:** February 28, 2026, 07:40:53 pm »

I need to weld here

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For this engine

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Stoker · « **Reply #4 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.

RedRyder · « **Reply #5 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.

Stoker · « **Reply #6 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?!?!

Jim · « **Reply #7 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.

cheepo45 · « **Reply #8 on:** 9 hours ago »

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

Stoker · « **Reply #9 on:** 9 hours ago »

Quote from: 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.

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!

Fullraceflathead · « **Reply #10 on:** 4 hours ago »

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.

RedRyder · « **Reply #11 on:** 4 hours ago »

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

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komet163b · « **Reply #12 on:** 3 hours ago »

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

RedRyder · « **Reply #13 on:** 2 hours ago »

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..

Jim · « **Reply #14 on:** 40 minutes ago »

Good luck with it Gil

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Author Topic: Need To Weld to Repair a Stirling Cycle Engine (Read 174 times)

RedRyder

Need To Weld to Repair a Stirling Cycle Engine

cl350rr

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RedRyder

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RedRyder

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Stoker

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RedRyder

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Stoker

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Jim

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cheepo45

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Fullraceflathead

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RedRyder

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komet163b

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RedRyder

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