Welding

[Pond Life]

Now you've realy let the frogs out of the basket. Sounds like you like to keep busy !

Couple of questions for you.

You do any TIG welding, or ever get involved with Tig Units they sell in Thailand ?

You mentioned wind generators, what motor/generators have you used in them ?

Ta

[Maizefarmer]

Now you've realy let the frogs out of the basket. Sounds like you like to keep busy !

Couple of questions for you.

You do any TIG welding, or ever get involved with Tig Units they sell in Thailand ?

You mentioned wind generators, what motor/generators have you used in them ?

Ta

Pond Life

I can TIG weld and I do weld - and I have an inert chamber - but no, welders are not part of my inventory - althtough if you want some rods I have a few boxes of different types lying around.

Wind Gennies - I build my own motors - make the comutators in the workshop - right down to laying out the magnets and winding the colis - would you like some pictures?

Last year I built and sold 4 units - 3 x 3.5KW and 1 x 5Kw unit - though I can wind up to 12Kw. They can all be configured for High Amp/Low Voltage or Low Amp/High Voltage. Outputs are AC. AC/DC conversion and Inverters I do not make - they are serial produced producst which which there is no way I could make as one offs cost effectively.

MF

MF

Edited April 19, 2007 by Maizefarmer

[Pond Life]

Sounds good MF, couple of TIG questions for you.

I just bought myself a neat little TIG/Arc set up, bought in Thailand, I think the brand name is Weldpro & its a 180 A inverter type. Cant find it on the Net, Im teaching myself to weld with the aid of a book & the internet.

Unfortunatly the manual that came with it was just a few pages, photo copied mainly Thai & just basicly nameing the controls on the front panel, it didnt even do a complete job of that.

So can you or any of our other listeners tell me what a 2 position switch labeled 2T & 4T would do.

Also a rotateing knob labeled "downslope" ?

I've mainly been concentrating on the Arc side first to get me up & running & construct work benches in my new workshop. But did have a little play with the TIG.

Once I got over the suprise of it looking, sounding & acting like a flame instead of an arc I then ran into the same problem as I did when trying my hand at gas welding as a kid, namely I'm completely unco-ordinated with my left hand doing the filler rod, to make matters worse the weldpool is tiny.

How can I make the weld pool bigger without upping the power & blowing a hole in the metal ?

I've got tungstens of 1/16 & 3/32, followed the welding book I bought & made them long sharp points ground length ways, but also tried blunting them down a bit to fatten the flame, but not much success.

Any sugestions ? I'm trying to weld 1" square tube 1.6mm wall.

Onto the generators, unfortunatly no wind at my place, but i've been playing with the idea of water power, so was interested by the mention of home wound motors, the best ones I've seen on the net were based on car disc brakes & axles, yours anything like that ?, id definatly be interested to see some pics.

Im presumeing if you produce AC at high Amp & low Volt you can put it through a wheatstone bridge to convert to DC for battery chargeing, what do you do with the output from your turbines ?

Anyone else with welding or generating experience is very welcome to throw in their penny's worth.

Think I should start a new thread ?, not exactly farming tho is it ?

Thanks

[chownah]

One method to make the weld pool bigger is to up the power and then to keep the heat moving around more....either back and forth across the line of the intended weld to make a wider puddle or forward and backward to preheat the area ahead of the puddle and then back up onto the puddle...the idea is that if you spread the heat a bit you will get a wider or longer puddle without it being much deeper....too deep and you burn through. Sometimes it is suggested that beginners lay down a heavier bead so that it can act as a heat sink or safe spot so that you alternately back off onto the thicker bead material behind where you are working and then quickly move ahead again to advance the puddle....the bulk of the puddle is on the thicker weld bead so there is less chance of burning through...but the result is a thicker bead which is not so neat looking but the idea is to give the beginner practice in controlling the puddle...as the skill develops you can gradually change style until you can make the small puddle work fine giving nice tiny welds.

In welding the tubing if you get a good fit so there is no gap between the pieces to be welded then the gas shield around the tip can be adequate but if there is a gap then the best thing is to purge the inside of the tube with your shield gas and then keep a small trickle of shield gas going into the tube to keep it air free inside.

I'm going to guess about the meaning of the "downslope" knob. When you initiate the arc it is beneficial to have more heat at first to get the pieces heated to welding temperature quickly and then the heat can be reduced....my guess is that your unit does not have foot pedal control of the heat so this is a way to give you a bit more heat for preheating and it is variable via the knob so you can adjust for the amount of preheat to match the thickness of what you are welding.....this is a guess so I might be off the mark. Its been awhile since I did any welding but I don't remember a 2T or 4T adjustment.....also the stuff I did was pretty basic and I never did use most of the possible controls on the various machines I used.

As to the left hand......practice...also for me it helps if I arrange stuff so my left hand (holding the filler rod) has something to rest on to steady it.

Also do you know about polarity...direct and reverse? Seems like you want reverse for most stuff and direct for aluminum....or am I getting it backwards?...its been a few years but this really does make a difference with the heat.

Also, where I learned they teach gas welding first to give the idea of how the puddle works...if you're having problems you might want to try some gas for awhile to get familiarized.

Chownah

[Maizefarmer]

You're right Chownah - you are guessing ... if you were taught to weld you'd know exactly what "downslope" means: because it is ONLY used at the end of a weld - not at the start!

Pond Life - adjustable upslope and down slope.

Upslope ramps up the current to assure for a smooth current draw and less demand from primary current supply when you initiate welding. By smoothing the weld intitiation process you reduce sparking. All this happens in micro seconds. In practical terms: it is the time taken for the welding current to rise from "crater level" (meaning standby or idle level) to "welding value" and occurs in those micro/millisecs as you bring the tip of the tungstun electrode onto the piece of steel you are welding.

Well a Chownah type explination doesn't tell you much practical, does it. The question should be - just when do you use, and how?

You use it if you are getting a lot of sparking as you start the weld - INCREASE your Upslope.

Okay - now Downslope

Downslope is used at the end of a weld - in simple terms it is the amount of time taken for the welding current to drop from welding value back to crater level, and is helpful in ensuring/establishing a good end weld/weld finish. You need to find a balance in using it - to little and you will have a "sharp" end weld and increased likely hood of cracking. to much and you may well find the weld extends further/deeper than you want it to.

It has a 3rd purpose - it is a circuit well suited to Inverter type welders, helping to protect those rather large power rectifiers you can see inside the casing from current spikes (but that is another issue).

2T and 4T is terminology used for different types weld "switch on" and Weld "switch off" modes known as "tact modes".

2T (two tact) - means welding current will flow when the current button is depressed and is intitated by one press of the current button on the torch.

4T (four tact) - means welding current wil not flow as soon as the current button is depressed - it will require a second press or extra/deeper press.

Question - the button on the torch - when you press it, is it a single or 2 stage press? - if it is only a single stage press, then you should leave your Inverter set to 2T. Change to 4T if you get a 2 stage torch or remote foot peddle to accomodate the extra stage. Dont worry about this stage in the beginning.

Weld Pro - they have a large show room on Sukhumvit around Soi 30 or 40 - heading towards the new airport it's on the right hand side. Whats the model number - if any - or does it just have 180A in the model id.

They're fine - nothing worng with them, there a clone of the Lincoln and Miller Inverter types. What is important is your torch - and torch tip. While learning you are almost certainly going to mess up a few tips. Don't worry, I still mess them up after 20 years - you'll get the hang of it.

SEnd me a pixcture by PM of the front panel of this machine - and I'll tell you which Licoln or Miler manaual is applicable - that will be the manual to get and use.

MF

[Pond Life]

Thanks for the info both of you,

I'm in Dubai at the moment, so separated from my new toy, but I do have a good net connection which is why I'm sucking in info at the moment & will try to put it to use when I get back to Thai (27 days).

I dont remember there being an upslope knob, only downslope.

Cant remember the model (4letters 180 3letters) is the best I can do.

I'll go & look at the Lincoln & Miller sites to see if I can spot it.

In my first 30 min attempt with the TIG I messed up 4 tips, so bought a box full.

I bought thoriated tips for steel, they have a colour marking (cant remember what) whats the colour code for aluminium (un thoriated I think). I'll be sticking to steel until I get the hang of it, but I am aware of the polarity change for Aly.

I think the switch is single stage, no sign of a conection for a foot pedal.

I found out the hard way that pipe joints have to be ground to a good fit before you start, TIG doesnt seem to good for filling gaps. I've read about moving to torch around to spread the heat, but it all seems to happen rather fast at the moment. Practice practice practice.

Thanks again

MF, I had a re-think about the wheatstone bridge rectifier, I'm guessing with the high output youre produceing it would be hard to find diodes that could take the current.

What do you do with your output ? any battery storage ?

[Pond Life]

The closest model I can find is the Lincoln V160-T, mine doesnt have quite so many controls.

The 160 is DC only, I'm pretty sure mines AC/DC, I certainly hope so or I've cocked up.

Downloaded the manual, minus the 10 pages of safety warnings.

MF, Thanks for the tip.

[Maizefarmer]

PL

Aaaah - the dreaded tip experiance has already been experianced ..... make sure you use the right tip for the right steel or alloy - get your colors right.

Yes - that is possible: you will have Down Slope capability on a welder before Up Slope is added - UP been added as an advanced feature, while DS is a basic feature found on many units.

DS & US features come into play with non-ferrous and hard to weld steels (Ti Stainless, tools steels, alloys ect) .... not so much an issue with the sort of mild steel you buy in Thailand for repair and construction work (which is what I guess you are going to be doing).

Some tips:

180Amp sounds a lot, but as I'm sure you know buy now - it ain't. Thats a peak output figure , not a constant service output - I guess a duty cycle of around 60/40 (but this speculation on my part). So - when it comes to pipes: chamfer the edge but not to deep and get it steep as poss (i.e. not wide), and although there is no rule per say, I'd say a 60-70degree chamfer starting from the od towards the id, but only around 25% - 30% of the thickness - not right through and certainly not any deeper than halfway through the thickness of the pipe. That should give you enough space to get the tip into the the area that needs to be welded, but also not been so small as to have to have it around in the gap to create enough heat and flow and then blowing right through and landing up with a hole.

Start for with a high DS setting and slowly wind it down as you get used to using it (using a high DS setting constantly will just help you chew through tips).

You'll get used to it and pick it up the skill quickly.

IR (International Rectifier) are in Thailand - you can get from them whatever you want - right up to 40K Amps !!!!!!!! - nulcear power station levels!!

I use old submarine batteries I bought in Australia many years ago - huge things rated at about 6k Amps! I only used stored power for the house. For everything else I use a diesel gennie, and the diesel gennie is tied into the dc storage, so it can be used to fill up the batteries. Still, I seldom run out of battery power for the house as the stove, water heating, house heating (yes Loei is Thailands coldest province in winter, and frost is regular in early morning winter) is bio-gas from cow <deleted> (there is a thread elswhere on the farming forum - I don''t want to re-hash it here).

I use 2 half wave class b's - easier to smooth out the ripple at high current than using a single full wave Class A - and if there is a spike it's confined to only half the cycle which in my case is important as all my comms run off an old Hughs V sat Network system that is touchy when it comes to ac supply (telephone, fax, TV, broadband - all goes through the V sat - I have no land line - will at last, after nearly 2 decades be getting a landline in October courtesy of Thai tel authorites!).

Sound like you have some background in electrical engineering (?)

MF

MF

[Pond Life]

Sound like you have some background in electrical engineering (?)

MF

No, quite the oposite, I'm a mechanical engineer (helicopters) & I detest electrics.

But like you said earlier its sometimes just easier/better to do it yourself. So I've learned the bare minimum I need to get a job done & go & learn some more when I hit a brick wall.

I've installed myself a 200w/48v solar system with 200 AH batteries running an 1000w inverter/charger, this was barely enough to run my tiny house especialy when I added a tiny fridge. I now have mains electric for when the batteries get low (& to run the welder) but plan to build a new house in an off grid location soon, I was hoping to suplement the solar with hydro.

Im thinking a 1000w would be plenty, so your units are to big for me & I doubt I have the power to run them.

But I'd be interested to get a look at one. Have you seen the brake disc models I mentioned ?

Im off to read up on rectification, I think I know the difference between 1/2 & full but never heard of class A & B.

Maybe we should start a mad inventers forum

[Maizefarmer]

Half wave is just that - in simple terms it rectifies only half the sine wave of the ac cycle - either the neutral side or the live side, but not both. Class A rectification is very clean, but is not efficient as it generates alot of heat.

1000w will not be enough for a house - my experiance says, that for most houses you need to have at least 2500, but idealy 3500watts avalible to draw on on a 60% duty cycle. Thats a fair figure for a 2 bedroom house - and it assumes you have a well insulated hot water tank and/or even better use gas.

Solar is brilliant for Thailand - has to be the best clean energy source and is usable year round in this climate - the problem is: cost of panels!

[chownah]

I found this link:

http://www.bmf.hu/conferences/saci04/borbely.pdf

It has a bunch of good info on tig welding....and specifically it shows plots of current vs. time that show how the current upgrade and current downslope work in relation to starting, welding, and finishing currents.....and it tells about the 2T/4T setting both with and without remote control (aka "torch pot" or "foot control")....and it talks about 8 operational modes and how the 2T/4T selection works in each.

I have always used welders that had remote control and I recommend it as it really gives you alot more control over heat of the arc and so it helps to control the puddle.

Chownah

[Maizefarmer]

Can't see dot how that will help someone learn to weld - is this another of your web searches full of impressive theory but little of practical help - or is it that you are just keen to repeat what others have said but in a fancy looking way impressive sounding way - but, yes I'll agree with on one thing - a foot switch is an excellent addition.

Chownah - keep it simple, keep it practical

Go to:

www.millerwelds.com/education/tech_tips/TIG_tips/index.html

Watch the video, then work through the other 5 in the series - a great intro containing pretty much everything I can see one would need to understand and practise the basics.

MF

[Pond Life]

So A class = full wave rect & B = 1/2 wave ?

Just been looking at wikipedia & they seem to be sugesting that half wave rect is basicly throwing away half your power, but I know what you mean about the heat, I fitted a bridge rect to an outboard engine, at first I didnt bolt it to the engine block & it melted. So got to wasteing alot.

Are your wind generators 1 or 3 phase ?

House will be very efficient, solar hot water/heating, gas cooking, LED & flourescent lights.

My first house has been a (small) experiment for this purpose, the biggest power consumers I've found are the inverter (20w no load) & the refrigerator.

On that note, has anyone out there ever converted a domestic chest freezer to a chest refrigerator by swapping the thermostat ?

Yes, solar panels are very expensive & so are good batteries.

Thanks for the link Chownah, will have to read it later as I have to go to work soon.

I dont think I have the option of fitting a foot control, the lincoln website talks about a 6 pin plug & I think mine only has a 2 pin for the torch switch. It also does a good job of explaining the use of 2t/4t.

[Maizefarmer]

Pond life

Yes, you are correct you would loose half your power - but go back and read again what I worte - use 2 (two) halfwave rectifier circuits - one for each half of the cycle (making sense now ...?)

Can be either - 3phase or single phase (it's just a different way of wiring up the circuit, and in some cases a change in the number of coil/magnet pairs - depending on output VAC/Amp required or wanted)

3 phase is more complicated to wire up but more efficient as its able to generate higher currents at lower trubine rpm's - and will run cooler (which means you can cut down costs be using smaller gauge copper wiring).

MF

Edited April 21, 2007 by Maizefarmer

[RamdomChances]

I've split this out of the "well pump" thread and deleted a few comments, MF and Chownah could you both try and remain civil towards each other.

[ozzydom]

I've split this out of the "well pump" thread and deleted a few comments, MF and Chownah could you both try and remain civil towards each other.

Perhaps water pistols at 10 paces

[chownah]

Can't see dot how that will help someone learn to weld - is this another of your web searches full of impressive theory but little of practical help - or is it that you are just keen to repeat what others have said but in a fancy looking way impressive sounding way

Chownah - keep it simple, keep it practical

Maizefarmer,

Thanks once again for putting me in my place and showing me how pitiful my actions are and how totally inadequate are all my attempts to help people here. I thought that the link I provided addressed Pond Life's concerns about the 2T/4T options and how it is used and did so in simple language that was easy to understand.....I guess I just don't have the common sense that you have in differentiating between what is useless impressive theory and what is practical help.

I think everyone here joins me in a heart felt THANK YOU SO MUCH for pointing out how deficient I really am since the posters and casual observers here are clearly not able to discern this for themselves.

Your dedication to the difficult task of informing everyone about these matters is a rare thing in life and should be cherished by all,

Chownah

[Khonwan]

Can't see dot how that will help someone learn to weld - is this another of your web searches full of impressive theory but little of practical help - or is it that you are just keen to repeat what others have said but in a fancy looking way impressive sounding way

Chownah - keep it simple, keep it practical

Maizefarmer,

Thanks once again for putting me in my place and showing me how pitiful my actions are and how totally inadequate are all my attempts to help people here. I thought that the link I provided addressed Pond Life's concerns about the 2T/4T options and how it is used and did so in simple language that was easy to understand.....I guess I just don't have the common sense that you have in differentiating between what is useless impressive theory and what is practical help.

I think everyone here joins me in a heart felt THANK YOU SO MUCH for pointing out how deficient I really am since the posters and casual observers here are clearly not able to discern this for themselves.

Your dedication to the difficult task of informing everyone about these matters is a rare thing in life and should be cherished by all,

Chownah

Chowna

You are clearly off-topic (as is now my post in consequence). You ask others (myself included) not to air personality clashes on the forum but rather request members to PM you with their issues. Why then are you not following your own advice? RC has (quite correctly) already removed such comments from this thread (including your own post, which you have now simply replicated). You've posted on several threads within minutes of each other in what seems, to me, to be an attempt to arouse further annoyance. I'll PM this message to you also (before this this & your off-topic post are hopefully removed).

Not impressed

Khonwan

[Gary A]

Getting back to the welding, , I wish you luck. I guess I'm just not coordinated enough to get the hang of TIG welding. I have a little buzz box arc welder and my welds look like chicken droppings. I spent more time trying to fill burn holes than anything else. Having failed at TIG welding years ago I decided that a MIG welder may be the answer for me. Even with that, I have to get my wife's nephew to come over if I have something that has to look decent. I use .8 mm solid wire and the next roll I buy, I'm planning to buy .6 mm. I use plain CO2 gas. With my limited coordination and welding only fairly thin mild steel I may not have to bother her nephew if I change wire size.

[Pond Life]

Thanks Gary, its good to know Im not the only one with 2 left hands, shakey ones at that.

MF, aha, i think Im with you now, so can I presume from the fact that you use 2 rects & not 6 that you are currently wired up single not 3 phase ?

You mentioned chamfering the ends of tubes, would you still chamfer tube with wall thickness 1.6 mm ? or thin enough already ?

I'll go & watch some Miller weld video's.

Has anyone seen those fighting fish that Thais sometimes keep in jam jars ?

They have to be kept in individual jars with cardboard sheets between them,

so they cant see each other & beat themselves to death on the glass walls trying to attack each other,

Is there such a thing as Cyber Cardboard ?

Thanks, all advice appreciated.

[Maizefarmer]

PL - aaaaah, I see one has been doing ones' homework!

Neg, I wasn;t refering to any particular example - it was a general statement in reply to the Wheatstone full wave comment -simply that instead of rectifiying through one circuit, my personal preferance is to use 2 seperate half wave circuits - but to answer your question, yes, the house is single phase. The workshop and dairy parlour draw power from a 3phase gennie.

Back to welding - chamfer the edges of a 1.6mm pipe? No, I wouldn't bother with steel that thin - just take a file to the edge any remove rust and dirt (and galvanising - which may well be on a pipe that size) that could get in the way of the electrode, and wipe the area it afterwards with a cloth with some tinners to remove any residual grease/oil - that should be sufficient. If you are going to be welding RSJ's and similar - yes, then a chamfer would help a lot.

MF