Oxy-acetylene at home

Hi All,

Ive moved out of the hussle and bussle of central london into a house with a small outbuilding that I intend on using for workshopping purposes. Ive managed to get myself a lathe (that Im quite chuffed about) and am looking for a mini mill (if anyone has a Warco RF-30 sized machine for sale, Im interested).

While the excitment of the new gaff plus the new machine hasnt yet died down, I would quite like a way to stick metal together and Oxy-acetylene is by far my favourite method. I have a setup I can use at work, but that isnt ideal for long term and want something at home. I was wondering if anyone has ever attempted to do the same and know the pitfalls. I am aware I will have to inform my insurance, but thats a small hurdle. I was also going to inform the local fire department, as it seems like the correct thing to do.

If its all too hard, I'll get better at tig, but it doesnt have the same romance about it. Plus Im crap at tig welding. And I hate it.

After speaking with a pal, turns out I can just get an oxy-propane setup, and still use a gas inline fluxer, which is ideal. So Ill do that.

Tell us more about the oxy-propane setup? I'm hoping to be in a similar situation soon.

Would love to hear your experience of an oxy-propane set-up once you're up and running. Looking to do the same thing myself in the near future

Subbed.

I have oxy propane at home. It's easier and safer to store the propane so seems like a no brainer for the home workshop. It burns a little less hot than acetylene but this just means it takes slightly longer to get the work up to temp.

Which is probably a good thing for a novice brazer right? Less chance of overheating things?
Referring to myself here, not the OP.

No you can still very easily cook it 😁 I think it's probably a little easier using acetylene, you can maybe get away with a smaller flame which is easier to focus the heat with.
In any case, propane is fine for the hobbyist and will braze just fine

Oxy-Propane + [multijet tips](https://www.thewelderswarehouse.com/Welding-Supplies/Multi-Jet-Nozzles.html#:~:text=Superb%20Oxy%20Propane%20(or%20Propylene,Oxygen%20%2B%20Propane%20or%20Propylene%20gases.) = as close to acetylene as you need to be.

I used to struggle with heat control with a single jet nozzle, got these and was able to neaten things up considerably.

@Ph1ll1p if you do take up tig, knowing how to braze and having the kit will be beneficial for doing wee brazeons and such.

Things have escalated.

In an attempt to keep my insurance an close to the same as it is now, I've been pointed in the direction of a medical oxygen condenser. According to velosalon, 5lpm does fine, and they seem to pop up on eBay for okay money but go quite quickly. You can still use a gas inline fluxer too, which is my preference as they just are fascistic.

My new plan is to use one of those- my partner isn't at all keen on having bottles of gas in my small workshop so less of better. As it's only 4.5m x 2.5m and has to store all my bikes space is already at a premium.

I've only ever used propane for a massive wide tip for brazing forks as I had to do a few at once and a pal recommended it. All I can say is it worked well and it was loud, so I'm excited.

Ideally, in the future, I'll get a small Tig too, I really want to try silicon bronze rods (for dissimilar metals) but it's way down the list of cool stuff to get. Maybe next year.

Has anyone had any experience with one of those laser cut welding table? My preference would be one of those rhino carts, but they run 2k new and it's just way out of my budget.

It's basically the same as acetylene, but a little cooler and if I've read correctly the hottest point of the tip is slightly further away from the cone.

Should be good as getting acetylene down my drive would be a nightmare and after speaking to my insurance company it's not an economically viable choice for me.

You can use the same torches but a multi jet tip is recommended as it's easier to extinguish a propane flame.

Nice one, I'm excited to get a torch of my own! I think Tig is invaluable in most situations, it might even be the better option for a home/hobby shop but I just find brazing more.... Elegant? Maybe a stupid reason but oh well. I can do it, I'm just rubbish at it.

Shout as I have a half height acetylene bottle we could discuss sharing;)

Do you have a brazing kit?

I would avoid buying one of those lasercut fabrication tables and order the lasercut parts yourself - and do the cad if you have the time, add 0.1mm overall tolerance for each tab (0.05 all round) and it will need a knock to go together, maybe a slight fettle. 0.1 all round makes it a bit easier to go together though.
The Mac industries ones are very expensive for what they are, I think.
I did a basic 6mm thick 1x1m table with 100mm sides and reinforcement ribs and it cost me £170+vat to be lasercut. Its on a sturdy base frame and is flat within 0.2mm all over.
If you order S355 grade sheet it's more durable too.
If you go down that route, don't be tempted to fully weld the tabs through the slots, just tack it together, they're plenty strong enough and it'll be flatter with minimal heat into the top 🙏

For tig-brazing, try the side #8 filler rod. It's a phosphorbronze and I find it welds nicer. Really simple to weld with, ideal to fit gaps and plug holes before powdercoating, I use it if I want to weld a cosmetic seam with less distortion and it needs to be powdercoated. But it's not a particularly strong weld.
Saying that, my friend Tig brazed a fork with #8 rod and hasn't broken it yet! I wouldn't feel so brave!
Hope it all comes together 🌞🤞🍻

Hi Phil H :),

What Fish says. I've ALREADY DONE THE CAD and can get you a lasercut table in any size you want for a fraction of the price of one of the bought ones. I want to order one myself and the more you order the cheaper they get. Hit me up.

Re: Medical oxygen concentrators
Andy Armour suggests 7lpm. Be aware of the chinese ebay jobbies that are listed as 0.5-7lpm or similar. Quite often on these the amount of oxygen goes down significantly as the flow of gas goes up. i.e there are junk ones that are to be avoided, beware!

Re: Multijet tips
This is the way to go and was a gamechanger due to the flame stability when brazing. Avoid using acetylene tips, these don't have a countersink and the flame will extiniguish itself in use (a pain in the butthole). Propane tips work well, but are still not as good as a multijet tip. Multijet for life.

Re: Propane in use.
1) propane doesn't burn as hot.
2) the highest BTU of heat happens further down the flame, it is NOT the hottest point of the flame at the end of the cone. If you braze like you're brazing with acetylene you will make ugly blobby brazes. Because you'll be brazing with a wider part of the flame the technique to use is to flick the flame on and off the joint for heat control and to work FAST! Keep the braze right on the edge of the liquidus at all points.

I swear I've seen a video of Tom Ritchey brazing with a rosebud tip on his acetylene rig. That's the technique you want even if it's a different gas being used.

@Fishfabs

Its on a sturdy base frame and is flat within 0.2mm all over.

Is this from measurements of the finished table, or assumed from the lasercut tolerance?

The lasercut parts will arrive curved after all the holes are cut into them, but my 1x1 table ended up very flat (checked with feeler guage) once welded together. It took some time clamping to ensure all tabs are fully located all the way down. Rutland's sell some cheap sash clamps that help with that.
Attached a picture of the cheap 1x1 table we made (used for grinding and mig work), then one of the MAC industries trestles to show how they tab. Then the Siegmund table stuff we use all day every day.
Siegmund have bought out a new table which is about £1200 - 1200x800mm - worth the money if you use them alot, they pay for themselves.

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@Fishfabs thanks for the information, I'm guessing from the size of the tables in your images at one point you had a small workshop? I'm Very size restricted, and was wondering if it makes sense to get a 1m X 1m table then make myself a frame jig when I get to that point, rather than taking up about 50% of my space for just the table?

I'll have to keep everything super clean all the time (all tools will have wall mounts) but it's about the only way I can work it out. Or sell most of my bikes, but I don't really want to do that.

Yeah, I started with a smaller buildpro table (individual plates got annoying) bought with a business loan! Ha.
I'd definitely recommend starting with a 1.2m long table if you can, as a frame jig is a bit tight to squeeze into 1m

Sorry for screenshots from social media.
Peter verdone has been working on lay-flat fixtures that look fancy.
Siegmund also have these towers that support your own lasercut tube supports - but could be done nicely and much cheaper in other ways of course. Having lasercut parts that are tailored for different tube diameter while still keeping the frame Centreline would be really simple and accurate way of making a flat jig I reckon.

I did an upright frame jig but ended up spending a small fortune on fixtures to support everything on the table.... And I don't think upright is really needed? You can get some good tack welds quite far around a tube just from one side can't you.

The Taylor brothers and old school builders used to just sit tubes in v-blocks with bags of lead holding them down.

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Acetylene gives a much more concentrated point of heat, which is a big advantage if you’re welding rather than brazing. I have no issues storing a decent size bottle in my garage. In fact the first one came with a rig I bought, 3/4 full and untouched for 30years. I took it (somewhat gingerly) down to the welding supply store and they had a look and said to use it.

Keep a bottle of leak tester handy and check all the hoses and fixtures periodically and you’ll be all good.

That said, propane is a metric shit ton cheaper, so if you’re not welding, that’s a good option. The in line fluxers look amazing, they’re bloody expensive over here though. Be interested to hear if you find a more affordable option!

Oh, on the milling front, a friend gave me one like this recently. Much smaller footprint than the RF30 clones but really very capable. Has the huge advantage of not having to tram the head everytime you move it up and down. Worth a look…

https://www.arceurotrade.co.uk/Catalogue/Machines-Accessories/Milling-Machines/SIEG-SX27-Mill/SIEG-SX27-HiTorque-Mill

This is all extremely helpful info. I've been eyeing up the Mac Industries table for years but never pushed the button. Going to go down the laser cut route and build it myself.

Quick question, did you go for 16mm holes when ordering it laser cut or did you add any tolerance. I've got nightmares of filing every single hole to help clamps fit.

I think I went for 16.1mm.... I'll have to check.

I did one in 6mm but I think 8 would be better really, mainly because the clamps put alot of force through the holes when you do them up tight.

Most of the ball clamping bolts are designed around stops and table thickness of 12mm each, so are sometimes sold with spacers.

It helps to use a countersink and chamfer the back of each hole - so when the balls expand in the bolts they push against the chamfer instead of a sharp edge. Such a boring job, and I was too impatient!

Any good laser cutter business should be able to tell you their tolerances on the cut. I have been using accujet for years at work with excellent results, but have never costed anything personally.

I nearly won the Warco equivalent recently but missed the end of the auction.

I have managed to get my hands on a Warco Major milling machine plus tooling for a tidy price (which I'm quite happy about). I'm currently stuck in the feedback loop of I need to fix the shed to hand the bikes to make room for the bench so I can fix the lathe so I can make handles for the mill so I can get the table cut so I can buy the brazing setup. Basically it all starts with needing to spend money and that's a little tight at the minute.