Using brazing rod for small parts - good idea? ..and what about the flux?

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VicHobbyGuy

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I'm new to model building - I got a lathe just a few months ago.
I've read mentions/suggestions about using brazing rod for parts requiring small diameter brass/bronze rod.
Is this common, or would I be better to just buy brass rod ($$) from a hobby supply place.

And if using brazing rod - what about the flux? Is it easy to remove? Most of the brazing rod I see at PrincessAuto (my local Canadian equivalent of HarborFreight) is coated with flux.

Thanks!
 
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I have no experience of machining anything, yet, but I can tell you that here in the UK I bought from my local DIY superstore a 1M length of 4mm dia brass rod for £6. To me, that makes using anything else a false economy
 
I have used brazing rod for small suff I have (almost gone) some 6mm bare rod works for me
Gary
 
I'm new to model building - I got a lathe just a few months ago.
I've read mentions/suggeations about using brazing rod for parts requiring small diameter brass/bronze rod.
Is this common, or would I be better to just buy brass rod ($$) from a hobby supply place.

And if using brazing rod - what about the flux? Is it easy to remove? Most of the brazing rod I see at PrincessAuto (my local Canadian equivalent of HarborFreight) is coated with flux.

Thanks!
I buy brazing rod without flux for parts. It is lower in cost
 
Sometimes it's just handy to pick-up a piece of 1/8" brass filler rod and the welding supplies section of the store. This doesn't have flux.
 
I've used Tobin bronze as steam chest studs, in 4 and 5mm sizes. TB doesn't usually have flux. In fact, the majority of brazing rods i use do not have flux and in this, i think of the 45% silver I routinely use. I have 45% in both 1.6 and 3.2mm rods. The flux-coated rods have their uses, for sure, but most of my brazing is done without coated rods and that includes welding with TB., for which i usually use a powdered flux.
 
I've used 1/16" and 1/8" brazing rod for small parts but I think it is not as soft (harder) as 360 brass rod. Can anyone comment or verify?
 
I agree with the post above. You can machine brazing rod but it cuts more like bronze than brass. The flux coating comes off easily - often when you want it to stay on.
 
I'm new to model building - I got a lathe just a few months ago.
I've read mentions/suggestions about using brazing rod for parts requiring small diameter brass/bronze rod.
Is this common, or would I be better to just buy brass rod ($$) from a hobby supply place.

And if using brazing rod - what about the flux? Is it easy to remove? Most of the brazing rod I see at PrincessAuto (my local Canadian equivalent of HarborFreight) is coated with flux.

Thanks!
i haven done stick brazing in many years . Some rod may be bronze rod as that as used to repair cast iron . I generally just purchase what I need on Amazon of from McMaster Carr. Some of this has become very expensive . You should be able to get bronze TIG rod at a welding supply . They often will only have 1/16- 3/32 and 1/8” rods in plain but there may be stick in thicker that you can strip the flux off. PMResearch steam has some round and flat stock too . They have been very good to deal with they have some small metric taps and dies As well as scale steam fittings . If you buy on Amazon check your orders very carefully I’ve received the wrong size several times it’s usually not worth the trip to send it back unless you are close to a return center.
 
Bentwings has mentioned sources of very small taps and dies and my experience is that the internet is very hard to beat. Of course, you'll be buying stuff from the land of gleat manuflactures, but I don't have an issue with that when the prices are right. Just today, I took delivery of five of each 1.4mm and 1.6mm dies, I think for the princely sum of just over US$40 the lot, I think it was.
 
Bentwings has mentioned sources of very small taps and dies and my experience is that the internet is very hard to beat. Of course, you'll be buying stuff from the land of gleat manuflactures, but I don't have an issue with that when the prices are right. Just today, I took delivery of five of each 1.4mm and 1.6mm dies, I think for the princely sum of just over US$40 the lot, I think it was.
I too search the internet. And reviews some stuff has poor reviews I try and stay away from or quality . I did have one good experience I wrote a poor review and received a new product that was what I wanted in the first place. At no charge another sent me the correct part and said keep the mistake. So I have a part I’ll probably never use gathering dust LOL
 
Yes, brazing rod in the 1/4 inch size and larger make good punches and to make small pins for gunsmithing work....
 
The reason 1/8" brass rod is handy is that's the size you need for 5-40 thread. Not exactly the most common thread form these days, but still a handy size especially if you work on any PM Research kits.
 
Yeah, your US/UN form threads aren't as common as they once were and a particularly irritating one use is the 4-40 used on DB25 breakout connectors. Gawd, i frittered hours away trying to find screws to suit. i now have some on order - ex internet. I have, in the past, re-fitted those connectors for 3mm metric, but I'd rather not do that. And i haven't found much to grumble about in the quality stakes of taps and dies.
 
The reason 1/8" brass rod is handy is that's the size you need for 5-40 thread. Not exactly the most common thread form these days, but still a handy size especially if you work on any PM Research kits.
I don’t have much in bronze rod anymore. I have a little iv ordered for small parts but that’s about it bronze is great fit steam stuff over brass. Steam gets after brass after a while especially if very hot
 
If you think 4-40 is hard to source, try finding taps over here for the BA hardware Stuart supplies in their kits. :)

I've found it's usually cheaper for me, even with postage, to order the small taps and dies directly from England for some of the more esoteric threads.
 
If you copy and paste this phrase "Copper Aluminum Weld Flux Cored Wire Low Temperature" into the eBay search box, or Google, you'll find lots of suppliers. The sellers call this product "Welding rod" but in truth I believe it's just another brazing rod. I've seen diameters of 1.5mm to 2mm. The flux is inside, same as flux cored solder, in fact, at first glance it looks like common solder. I've been using this product for several years, and although it's sold to "weld" aluminum, I've found that it bonds to mild steel, tool steel, stainless, copper, brass, bronze, and of course aluminum. The melting point is spec'ed at 360 to 400 centigrade, so a common propane or butane torch can be used.

It's biggest drawback for me is that the flux is very hard to remove; I usually use sandpaper or a heavy wire bush.
 
Be careful what you use re brazing rods as these come in several grades and some may not be suitable for what you want and are not easily identified in the loose bare wire format without the box with the id on it.
the most common ones were Silicon bronze. Manganese bronze. Nickel bronze. Aluminium bronze. all these had different mechanical properties, so some could be ok for making say studs and others not so good.(note these were for oxy fuel brazing using powder flux ) there are quite a few other alloys out there that are used for TIG

Paul
 

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