Welding Equipment & Welding Supplies since 1993
Call Us On
0845 899 4400
01908 699802
0845 899 4400 | 01908 699802
Tel 01908 699802
(9am-5pm Mon-Fri)
Milton Keynes, United Kingdom
« Back to blog homepage

Model O Torch

Thursday, 19th March 2020
Graham (Tech Advisor)
The Welders Warehouse Online Shop

Model O – a little bit of History

We’ve been selling the original Model O Torch for some Years now.  It’s always been a popular torch, especially among Roofers, who use it for Lead Welding and LOVE the feel of the torch and the precise flame adjustment that can be achieved.

Now, after over 30 Years of the above model O, we’ve updated the design to incorporate some tweaks that customers have expressed a desire for.

Model O – the Next Generation

The first thing to say is we haven’t changed much!  After all, if a Torch is as popular as the Model O it would be stupid to re-invent the proverbial wheel 🙂

So what have we changed?

We’ve now made the Oxygen Inlet from a single forged piece of Brass, rather than two pieces brazed together.  This increases the strength and durability of the whole Torch, plus improves Oxygen Gas Flow.

We’ve tweaked the geometry of the valves to provide even better and more precise flame adjustment.

We’ve increased the angle of the Neck Bend as LOADS of customers, old and new, told us the angle on the old torch wasn’t tight enough.

Model O Nozzles

The original Model ‘O’ Nozzles are designed for Oxy/Acetylene or Oxy/Hydrogen.

Model O Nozzle (Oxy/Acet)
Model ‘O’ Nozzle for Oxy/Acetylene

These original Model O Nozzles are VERY small.  They’re numbered 1-5 with 5 being the biggest.  Having said “Biggest” it’s worth noting that the number 5 is only slightly bigger than a conventional torch No1.  So the term “Biggest” is somewhat subjective!

The most popular Oxy/Acetylene Nozzle is the No3, which Roofers use for Code 4 Lead Welding.  Although all the nozzles sizes  are popular.

No1 nozzle produces such a tiny flame I’m pretty sure you could weld a KitKat wrapper with it 🙂

Oxy Propane/Propylene Nozzles

Launched in 2020, our Pro-Jet dedicated Oxy/Propane or Propylene Nozzles.

These feature a small ring of tiny nozzles, surrounding a central main flame.  The purpose of this design is to allow the greater volume of fuel gas that’s necessary for liquefied gases, to flow and burn efficiently.

Model O Oxy Propane or Propylene Nozzle
Pro-Jet Model O Nozzle

Pro-Jet Nozzles are available in numbers 1, 2 & 3.  (3 being the biggest).

Customer feedback has been excellent, with Roofers telling us the No1 nozzle is ideal for Code 4 Lead.

Using the standard Oxy/Acetylene Nozzles for Oxy Propane or Propylene is ok, but the torch is difficult to light and the flame blows out REALLY easily.  This is because Propane and Propylene are liquifed gases that burn a lot slower than Acetylene.

Pro-Jet Nozzles overcome these problems and are much easier to light, especially in windy conditions!

Using the Model O

The single biggest problem that customers report with using their Model O Lead Welding Torch is difficulties with flame adjustment.  This usually means the flame blows out too easily when lighting, or the flame pattern changing on its own.

In 95% of cases, this is caused by too much gas pressure being set on the Regulator.  When customers report problems and we ask what pressure they have set, we invariably get figures around 1.0 to 1.5 bar.  The correct pressure is between 0.15 and 0.2 bar!!!!  This is barely off the Zero Pin of a Regulator!

Gas Regulator Selection

The problem of setting too higher Gas Pressure derives from one of two things

The operator thinks that 1.0 – 1.5 bar is the correct pressure IT IS NOT!

The operator has a 0-10bar Oxygen Regulator.  Trying to set a STABLE pressure of between 0.15 and 0.2bar on a Regulator with up to 10bar of pressure is virtually impossible!!!

Here at The Welders Warehouse, we offer a 0-4bar Oxygen Regulator for lower pressure applications, which is actually MOST applications!  A 0-4bar Oxygen Regulator is far better for setting and maintaining the stable low pressure needed for using a Model O Lead Welding Torch.  A 0-4bar Oxygen Regulator is suitable for most Welding and Light Cutting Torches.  A higher output Oxygen Regulator would only be necessary for Cutting Nozzles above 5/64″.

All our “Standard” Oxy Acetylene and Oxy Propane/Propylene kits are supplied with the 0-4bar Oxygen Regulator.

Even More Low Pressure Control

For even more control, we also offer a 0-2bar Multi Stage Regulator. This Regulator comes with or “Premium” Oxy Acetylene Kits

I’ve written a separate article on the difference between Single and Multi Stage Regulators

I’ve also produced a Video

Lighting a Model ‘O’ Torch

There is no real difference between lighting  Model ‘O’ Torch to lighting any other kind of Oxy Acetylene Torch.  It’s just more important to make sure the gas pressure on the Regulators is set correctly and only turning the Torch Valves by very small amounts at a time.  The key thing to remember is that with such small nozzles, small changes can make a big difference, so changes have to be made gradually.

Conclusion

The Model O Torch is still the first choice for Lead Welders and the new Torch fine tunes all the things Lead Welders loved about the original.  As long as the Oxy Acetylene Kit is set up correctly, the new Model O will provide Years of trouble free Lead Welding.

Visit our Model O page, where you will find prices and can order.

I hope you found this blog article useful, if things work out well for you, please feel free to post some pictures of your achievements on our Facebook Page

Please let me know what you thought of this article by leaving a comment.  Don’t worry, your email address won’t be added to a database or shared and you won’t receive any unsolicited email.

Cheers

Graham

24 comments

  1. David Winstanley says:

    Hi Graham, many thanks for getting back to me regards pacemaker and arc welding, safer so far to stick to oxy propane brazing, which kit I do have and use regularly.On the subject, I may well progress into oxy-acetylene.This brings me to your model o torch, can you supply me with the torch, and suitable propane nozzle please, I understand from your blog that the same torch can be used eventually for acetylene, and i would buy all conversion kit from yourselves at the time. My kit comprises of a cutting torch, which is a bit cumbersome for brazing.Many thanks, Dave Winstanley

    1. Graham says:

      Hi David
      Model O is available with Oxy/Propane (or Propylene), Nozzles and Oxy/Acetylene Nozzles. So whichever you buy, you simply need to swap Nozzles to swap fuel gas!
      HAVING SAID THAT, depending on the physical size of your work, the Model O may not be the best Torch for you as it’s a Micro Torch, mainly for Lead Welding and Jewellery work.
      Consider our Lightweight Oxy Propane (or Propylene) Torch this can also be used with Oxy/Acetylene Nozzles if you swap gas later!
      Can I suggest that before you place an order with us, you give me a call for an informal chat about your applications, that way we can make sure you buy the right Torch for you!
      You can call me on 01908 699802 Mon-Fri. It’s best to call after 11:00 as I’m often out of the office or on foreign Zoom calls until then.
      Hope I’ve helped
      Kind Regards
      Graham

  2. David Winstanley says:

    Hi Graham, I have welded for56 years with my Oxford 110 arc welder, but, have recently been fitted with a single cell pacemaker, and the common concensus is that arc welding is now a no no because of the EMI given off by this type of welder.This is akin to having all fingers removed for me.Do you know of any protective clothing which will allow me to continue. Many thanks.

    1. Graham says:

      Hi David
      I regret I don’t know of any suitable clothing.
      It might be worth doing a bit of digging on the EMI issue. Doctors tend, necessarily, be over cautious.
      Tig Welders often use High Frequency to start the main arc, as do some Plasma Cutters, and I can certainly see how these could be problematic for Pacemakers.
      I am unsure how a Stick Welder or Mig Welder would cause a problem as they do not use high frequency to start the arc. But I am no expert on Pacemakers!
      Sorry I can’t offer any real answers, but I definitely think it’s worth contacting someone better qualified. If you can find out the make and model of your Pacemaker, I would approach the manufacture for advice on this specific matter.
      Best wishes for your health going forward!
      Graham

  3. SImon Lunn says:

    I Graham, sorry, another query. Your hoses seem to only go down to 5mm bore. I’ve recently seen some very small and flexible hoses with 3mm bore from TM Technologies in the US for use with their Meco torch. Are you able to supply anything similar in the UK for use with the Model O, it’s all very pricey to import? In general I’m looking for greater flexibility and less ‘pull’ on the torch.

    Thanks, Simon

    1. Graham says:

      Hi Simon
      As we’ve now spoken on the phone, I won’t repeat myself 😀
      Cheers Graham

  4. Simon Lunn says:

    Hi Graham, I’ve come across what I believe is an old Model O body, which I’d like to use. Do you have a parts diagram so I can work out exactly which parts I need to refurbish the torch? Are all parts still available for the old Model O body, and do you offer a refurb service?

    I’ve been using my acetylene set up with Propylene for about 10 years. Is it too late to switch to Acetylene (and abandon Propylene) now with this set up or do I need to replace them. I’ll be getting a low pressure Oxy regulator anyway, as per your suggestions.

    Thanks for the very informative blog, really excellent.

    All the best, Simon

    1. Graham says:

      Hi Simon
      As we’ve now spoken on the phone, I won’t repeat myself 😀
      Cheers Graham

  5. Hi would you ship the model O gun to New Zealand, i would need 3 number

    1. Graham says:

      Hi Stephen, thanks for the question. YES, we can ship the Model ‘O’ to New Zealand. If you use the Contact Us form on our website to let us know your address we will let you know the shipping cost. Be sure to state that you want 3 Torches.
      Hope that helps
      Graham

  6. Jeff Terrell says:

    Hello Graham,
    Thanks for your prompt reply. I bought a general purpose triangular shaving hook (Toolstation, 58907, £2.92) to clean up the joints and the welding sticks before starting to weld and all my problems disappeared. Many thanks for your help.
    Regards,
    Jeff.

    1. Graham says:

      Your very welcome Jeff, glad all is OK now.
      Best Regards
      Graham

  7. Jeff Terrell says:

    Hello Graham,
    Last week, I bought a lead welding kit from you. It’s a very nice tool, but I haven’t found it that easy to produce a professional finish. In spite of cleaning the joints thoroughly with wire wool, I can’t get the solder to flow properly and I’ve therefore resorted to using flux. What do you use to clean the joints? Also, do you make your own welding rods from spare lead? I’m using a roll of lead which is probably used more for soldering than welding. Thanks. Jeff.

    1. Graham says:

      Hi Jeff
      Good to hear you’re pleased with the quality of your kit.
      Most pro Lead welders scrape the edge of the lead with a scraper tool to expose clean, bright lead. Essentially, you need to remove the dull grey oxide layer. Wire wool should also work, as long as you end up with clean bright material.
      Most pro lead welders will cut a thin strip off the lead they need to weld, to use as a filler wire. This guarantees the lead is exactly the same as the material to be welded, it’s also cheaper than buying cut lengths for filler wire.
      As long as both the lead to be welded and the filler rod are clean and bright (Oxide layer removed), you should not need flux.
      After that it’s down to technique!
      The Lead Sheet Training Academy in Kent offer some very good courses and also have some YouTube videos that might be worth you watching (search “Lead Sheet Training Academy” for within YouTube).
      Other Lead Welding course providers are also available, including some local Colleges.
      Hope I’ve helped.
      Kind Regards
      Graham

  8. John says:

    How do you set an oxy propylene set up but using the same oxy/ acetalyne setup

    1. Graham says:

      Hi again John
      You must not use Acetylene kit with Propane or Propylene!!!
      Propane & Propylene will corrode the inside of Acetylene Hose and internal parts of Acetylene Regulators and Flash Arrestors. You must use a Propane Regulator, Propane or “Fuel” Flash Arrestor and Propane Hose.
      Sorry that it’s probably not what you want to hear! but you need to stay safe, so I hope it helps.
      Cheers Graham

  9. John says:

    Can an oxyturbo kit be converted to take a model o torch or the lead master torch

    1. Graham says:

      Hi John
      Thanks for the question.
      YES, you can.
      You will need to cut the Oxy/Turbo Torch off and fit a Gas Hose Nut and Tail set to the Hoses. You will need a “5mm RIGHT Hand ¼” Thread” for the Oxygen and “5mm LEFT Hand ¼” Thread” for the Fuel Gas.
      Either the Model ‘O’ or LeadMaster will then fit onto those fittings.
      You can find the fittings via the following Link and using the “Options” Drop Down Menu.
      Gas Hose Nut & Tail Set
      Hope I’ve Helped
      Cheers Graham

  10. John Hall says:

    Hi, is it possible to use the model 0 with propane instead of acetylene?
    Cheers John

    1. Graham says:

      Hi John
      Thanks for the question. Yes, it is possible to use the Model O with Oxygen + Propane. You can use the standard Nozzles, but will need a bigger one than with Oxy/Acetylene. Oxy/Propane with a No4 or 5 Nozzle will work fine. Oxy/Propane is a bit harder to light and will be more prone to blowing out, this is because Propane is a much slower burning gas than Acetylene. But other than that, all will be OK.
      Hope I’ve helped
      Cheers Graham

  11. nicolas castro says:

    hi graham
    what is acetylene pressure for model 0 torch

    1. Graham says:

      Hi Nicolas
      Thanks for the question.
      Both Acetylene and Oxygen should be around 0.15bar (2.2psi), depending on Nozzle Size. You should certainly not exceed 0.25bar (3.7psi) for any nozzle as too much pressure will make the Torch valves VERY finiky to adjust.
      Our Next Generation Model ‘O’ Torch has the pressure for each Nozzle on the box.
      Hope I’ve helped.
      Cheers
      Graham

  12. Richard Fenwick says:

    Very useful and informative. Please could you do an article for beginners like me trying to use and oxy/propane torch but without a lot of success particularly with regard to nozzle sizes, lighting and adjusting to the correct flame type. Many thanks.

    1. Graham says:

      Thanks for the Comment Richard. There is already a blog article that covers some of what you’re seeking, called “Setting up Oxy Acetylene Kit“. I will endeavour to add to this so that Nozzle Sizes and Flame types are covered.
      Cheers
      Graham

Leave a comment

Your email address will not be published. Required fields are marked *