ANSWERS : Workshop

I am trying to make a Stirling engine, for the displacer piston I need to weld an aluminium tube to some aluminium plate and possibly bar but I don't have any welding equipment, so any suggestions?

Comments

[rickharris]

Epoxy will work fine unless directly in the flame.

Otherwise you can get aluminium rod that will work at very low temps - i.e. with a gas torch.

[The MadScientist]

Do you mean gas torch as in a blow torch?

If so will oxidisation be an issue?

[The Skinnerz]

From what I've seen, that low temperature aluminium rod is perfectly workable with a medium/small propane torch, and seems to be capable of making a clean join, even if re-melted a couple of times.

[seandogue]

Based on what I've read both in your query and the followup, I'd say that you should consider looking up a shop in your area and asking them how much it would cost to have them weld it for you. You might find that it's less expensive than you think, and having it break due to over temping the epoxy is just a waste of your time...and your time is worth money.

[jj.inc]

JB weld, It will work great and I use in on aluminum all the time in HHO generators. I use the putty, but you should be able to use the more liquid stuff if you have to flat surfaces.

[steveastrouk]

The hottest expoxy I know is good to around 200 C. Would that do ?

There are plenty of designs out there for "glued" stirling engines !

Steve

[The MadScientist]

Well I just did an experiment and I found mentholated spirits (my most likely heat source) burning at above 700C so that means that the potential heat inside the engine is above 700C (however doubtfully).

I will probably go to a specialist store that may have super high heat super glue, today I had a look at a general hardware store and the best I found was also 200C.

[The Skinnerz]

Unless the joint is going to get quite hot, most adhesives designed for metal should be fine, although a bolted join would look far better. If you insist on welding, I hear that with practice, aluminium can be welded with a hydrogen flame using normal acetylene equipment.

[The MadScientist]

It may get quite hot inside the engine so regular super glue probably won't hold.

[The Skinnerz]

You may have more luck with 'liquid weld' style adhesives, especially those intended for automotive repair. What sort of engine are you building?

[The MadScientist]

Stirling engine.