TIG flowmeter opinions?

I've just started getting set up with a small TIG outfit and I need an argon flowmeter. I can get Victor, Harris and Smith in the local area,
I'd just like some user opinions before spending money. The price range is pretty wide, about $60 for a single-stage on up to $250-300.

plastic flowmeters, other makes use glass. Supposedly, Smith has a special design so the ball doesn't stick. Any reason to go with one over the other?
Harris has a dual flowmeter that looks like it'd be handy for back-purging tubing and the like, that's something I'd be interested in. Somebody in an old post said you could retrofit most any flowmeter with a tee and an additional meter tube and valve segment. Has anyone done that with any of the makes above?
I guess the main question is do you get any extra performance as far as work quality for the extra dough at the high end or should I just get the cheapest model I can?
Delivery pressure is another thing, I've seen otherwise identical models with different preset delivery pressures, 35 psi and 80 psi seem to be popular, I've seen some with 50 psi. Any reason to go to higher or lower pressures, other than solenoid valve and torch pressure ratings?
Are there flowmeter tube protectors available? I envision something similar to a gauge glass protector like they used on portable steam engines, boilers and locomotives, a thick-wall metal tube with strategic slots milled in it so the ball level can be viewed, maybe with a mirrored back(LED lighting for dark spaces optional). Maybe it's an answer to a problem that doesn't exist, but that flowmeter tube looks a little fragile for an industrial environment.
Nothing like a few wide-open questions...
Stan
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@prolynx.com wrote:

I don't think you will see a difference in the weld quality. You might see a difference in the argon usage though. With a single stage regulator, the output pressure will creep up as the cylinder pressure drops. Unless you re-adjust the flow rate occasionally, it will creep up over time. If you were to T the argon line for backpurge, you might want a two stage regulator because they do a better job regulating with flow variations that you are likely to see with a backpurge setup on the same regulator. I use a separate tank and regulator for backpurge so I can't say for sure.
I use the single stage Victor with the plastic flow meter. I picked it up off the "bargain" table and had to replace the sight glass since it had had the end popped off it. I have only been using this one for a few years, but have never seen any signs of the ball sticking.
Good Luck, Bob
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
snipped-for-privacy@prolynx.com wrote:

I prefer the Smiths with the glass tube. I added a Tee fitting on mine for back purging. I just added a second flow tube from an old flow gauge.
For a while I used a tank splitter that allowed me to use 2 flow gauges on one tank, but it was a pain to remove for tank change overs.
--
"I love deadlines, especially the wooshing sound they make as
they fly by" - Douglas Adams
  Click to see the full signature.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
There has been discussion of flowmeters, TIG and arrangements for backpurging on s.e.j.w. before. What worked well for me: (first, let's assume all flowmeters have both a column showing the flow and a needle valve for adjusting flow) -- a single stage regulator on the cylinder, set to a bit higher pressure that gave the necessary flow through the torch and backpurge with the flowmeter valves wide open - maybe twice the flow. Off this one incoming line, feed both the torch and the backpurge through a Y-fork. On the branch to the welding machine you have just a flowmeter. The TIG welder has an internal solenoid turning on and off the gas. On the backpurge supply you have a flowmeter with its needle valve, but then, near where you are working, you have an on/off valve with a big handle. You fine-adjust the flow at the backpurge flowmeter, but you can set the argon flowing only when you are about to weld - and shut off when you are done, while leaving the flowmeter alone. With welding being usually stop/start, you are better off with a decent flow when the valve is open and then shut it off, ratehr than have an inadequate flow all the time. The reason you set the regulator on the cylinder to a slightly higher pressure than absolutely needed is so that if you adjust the flow on one of the flowmeters it doesn't noticeably affect the other one. That pressure in the delivery pipe to the Y-fork and into the flowmeters is very low. There is no issue of pressure rating of the flowmeters. Is that advice OK with everyone?
Richard Smith
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
I just bought an emergency replacement flowmeter from harbor freight tools for $35. it works great. I dont know how long it will last but would probably be fine for occaisonal use.

Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload
In Britain I paid about that for a British-made brass-bodied flowmeter - and usually things in Europe cost more than in the States. Maybe get to know your local welding supplier. By the way - Argon is very "leaky". It will find leaks where compressed air won't find a way out. It probably isn't worth getting "inert gas proof" pipe, but those fully-wrapping-around crimped fittings around the "barb" of your brass pipe fittings are worth-while. Turn off your bottle valve when you have finished work unless you find that the hose will hold Argon pressure for days without any observable loss. Well, you should do that anyway...
Richard Smith
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
<%-name%>
Add image file
Upload

Polytechforum.com is a website by engineers for engineers. It is not affiliated with any of manufacturers or vendors discussed here. All logos and trade names are the property of their respective owners.