Spot welders......

[Bob Carriere]

Advice from those who have used one.....

Bought a Miller hand held spot welder.... model 52 ...works on 220 volts..... can do 3/16 thick combination.....

Tried it for the first time last weekend..... it is a tremendous and fantastic 3/16 hole punch.

Can't seem to make it work right.... even read the instructions.

Tends to burn holes. Played with the settings such as pressure...tip alignments.... and duration of applied power..... same poor results.

The welder has a momemtary toggel switch to apply power...... just need to tap it on off for a fraction of a second..... and it still burns holes...

Phil... I know you have one and you used it on cab sheet metal around 18 G

What is your secret..? how do you control the duration of power...?

One of the obvious solution is to go back to the vendor and purchase an expensive $400 in line timer that will control heat to the fraction of a second... would rather spend my $$ on CMP trucks....

Will do some pictures this weekend...

Bob

[Phil Waterman]

Hi Bob

I'll check the Miller web site to see I can figure out what is going on. Try and figure out how or if model 52 is different from mine. My welder always seems to work well with fresh steel. Or with steel that I have cleaned all the surfaces have been cleaned real well. Best tool for cleaning the steel without grinding away material are the 3m abrasive pads for the air grinder.

Funny you should ask this question now as two weekends ago we had our MV club's annual welding seminar at my place and one of the things we spent a lot of time on was spot welding. and the metal prepping.

Cheers Phil

[Phil Waterman]

Hi Bob

Want to check I've got the correct model. LMSW-52 220 not the LMSW-52T 220 W/WELD TIMER

http://www.millerwelds.com/products/...__air-cooled_/ I'll start reading

Here is the web site for the spot welder I have http://www.htpweld.com/products/spot...quickspot2.htm


Hi Bob

Just found that I need the serial number to be able to down load the manuals.

[Phil Waterman]

Hi Bob

Was able to down load the current version of the manual and read through it. Couple of points:

1. I wouldn't run out and buy the timer unit. Think the problem is not lack of auto timer. Half the time I do the welds almost by ear and eye. Sound of welder changes as metal heats.
2. Try some sample welds after cleaning all four sides of the metal and post some pictures (or e-mail them to me)
3. Do you have a AC volt meter that one of the guys could read the voltage of the 220 voltage going to the welder. I had problems with mine when I built the barn as it was fed from the house to garage to barn to much line drop. While your at it check both legs of the power panel. I have to turn off the halogen shop lights when I'm weld sheet metal to angle iron with the spot welder.
4. Can not over empathizes need to clean/polish the steel.
5. I've made up some sample combination sheet metal thicknesses to put between the tips when setting the tip pressure. On them I've written the weld time and heat setting.
6. Just as with any other type of welding when you have not done it for awhile you have to practice, I have to force myself to practice until I get good again time.
7. The manual is correct about shape and size of tip contact area being important.
8. Holding the pinch pressure until the metal is no longer red hot is also important and a problem that I had trouble with until I remembered that you have to hold the pressure after releasing the trigger. Some thing like a three count should do it.


Await the results of further test.

Cheers Phil

[Bob Carriere]

Hi Phil.....

1. I wouldn't run out and buy the timer unit. Think the problem is not lack of auto timer. Half the time I do the welds almost by ear and eye. Sound of welder changes as metal heats.***How long do you leave the power on...?
2. Try some sample welds after cleaning all four sides of the metal and post some pictures (or e-mail them to me)....that maybe my problem...I used scrap metal with some surface rust bloom......
3. Do you have a AC volt meter that one of the guys could read the voltage of the 220 voltage going to the welder. I had problems with mine when I built the barn as it was fed from the house to garage to barn to much line drop. While your at it check both legs of the power panel. I have to turn off the halogen shop lights when I'm weld sheet metal to angle iron with the spot welder.....I have a 200 amp service dedicated to the barn as a seperate service.......
4. Can not over empathizes need to clean/polish the steel........ will do new samples with new clean steel....
5. I've made up some sample combination sheet metal thicknesses to put between the tips when setting the tip pressure. On them I've written the weld time and heat setting......Good suggestions....
6. Just as with any other type of welding when you have not done it for awhile you have to practice, I have to force myself to practice until I get good again time.
7. The manual is correct about shape and size of tip contact area being important.....I have new tios and spare tips.... how often do you redress..as in how many cycles/spot welds between dressing
8. Holding the pinch pressure until the metal is no longer red hot is also important and a problem that I had trouble with until I remembered that you have to hold the pressure after releasing the trigger. Some thing like a three count should do it. .....never had to do that..... I barely cycle the switch on for a fraction of a second and it burn a hole and throws sparks all over... the metal prep may be my single biggest problem

Will cut some new strips in new clean metal....degrease.... various gauges primarily 18 G and 14 G at this time...

Stay tuned...

Bob

[Phil Waterman]

Hi Bob

Sounds like good starting points, after you try some more experiments and send photos we should know more.

I'll check the actual cycle time on mine welding at different settings.

When you take your pictures include on of the tips. I have differ size tips and the small ones will burn through more easily than the big rounded ones. I'll take some photos of the tips I have.

Glad to here you have a separate power service to the barn, when I redid ours to install the generator transfer switch I separated house, garage, and barn. Which solved a lot of my problems. I've still got a problem in the barn that I've got to shift around, all the lights ended up on one side of the circuit.

Cheers Phil

[Anthony Main]

The metal you intend to spot weld needs to be clean, No rust or paint
as this stops the welder making a proper electrical conection between
the metal & Blows holes instead of welding!

[Mike Kelly]

I live in a rural location and the mains voltage drops down each afternoon , around 4-5pm. Welding jobs after 5pm are hopeless.

Has anyone successfully spot welded aluminium sheet panels ? I've seen it done by a chap here who makes new Land Rover body tubs.
Mike

[cantankrs]

Oooooohhhhhh, might explain some issues I had many years ago on a job I was doing using a spot welder Dad had dragged out of his shed and got insulation tested before he'd let me touch it. Need clean clean metal on all surfaces. I also noticed there's not much time between a smick spotweld, and something that looked like a rough impact crater.

BTW, on a side note the welder had no arms or points so I first tried making steel arms and copper points but too much resistance (from the steel) of course. So Dad to the rescue again when we were visiting my late Grandfathers place and he ducked into the old garage and from some hidey hole brought out two offcuts of almost 1" brass rod about 15" and 20" long that Grandad had 'rescued' from the scrap wagons at the submarine base at Albany during the war! He saved them for a rainy day...

Regards

Alex
--
M3 Grant, Val, Ferrets, WM20, CMP's

[Bob Carriere]

Well Mother's day reduced my barn time but the progress was NIL !!!!!

I sheared a whole bunch of one inch wide strips in 18 guage...14 gauge ... and some 40 thou satin coated......

I cleaned the surfaces and held them tight at 90 degrees with wisegrips....
...also cleaned the tips...... readjusted for exact alignement and flat filed the contact to mate perfectly.....

Blah...... sparks all over and another crater.....

Seems that the top electrode erodes and throws out a perfect circle of sparks... the result is a cratered top weld and a smooth bottom surface where the spot weld is clearly visible but not distorded.

I tried various combination of light gauge together and mixed thickness.... same results....... and I am just cycling the switch on/off for what can't be more then half a second if not shorter.

also to be noted...... I have to twist the sample sheet metal as they are held fast fuzzed to the top and bottom electrode.

when I twist the spot weld to see the penetration the top peice being more cratered shears of on the outside of the button leaving apecfectly round 1/4 hole in the top piece.....tips at 3/16 at the tip......

According to the Miller "tekkie support" in Wisconsin ( he was more like an athletic support)..... his suggestion was to use a longer extension cord to reduce the amperage to the spot welder.....

Pictures..... I was so p****d I never bothered with pictures.....

The local distributor has offered to line up the travelling Miller sales person to lookover my spotwelder and run some demo in the Linde Gas training centre....... awaiting news....

I cannot understand why Miller would sell a spotwelder that needs to have the power cycled so fast that it becomes almost physically impossible to do.

Phil claims that he can literally see/feel the metal welding so I assume that he is holding the switch and counting "one thousand an one...." "one thousand and two..." and getting good results.....

Unless my China made Miller is defective or needs soya sauce....

Bob C.

[Phil Waterman]

Hi Bob

What you are describing sounds like something else is going on. Tomorrow I'll video some spot welding and post so that you can see how my unit works maybe from that we can figure whats up with yours. Almost sounds like it is putting out to much power.

If you can get a demo out of the Miller rep using your gun it might be worth the time and effort in tricks of the trade.

HTP has (with my permission) referred prospective equipment purchasers to me to actually see their stuff in operation. Results in a sale for them in the three people who have actually come out. Funny thing is the people always seem to buy equipment one or two notches up from what I have.

Cheers Phil

[cantankrs]

Hi Bob,

Sure doesn't sound right. I'd be testing it at some power source elsewhere just to eliminate that (like across town, or in town - depending where you are), and then get it checked out by a service person unfortunately. I seem to recall about 2-3secs on the switch on our old model.

Regards

Alex

[Phil Waterman]

Hi Bob

Didn't spend a lot of time making this pretty or really explaining it figured I'd start with sound and video. You will hear two different welding sounds one is the regular weld mode the other is a pulse mode.

In looking at the manual for my unit which is different company I was looking at the wiring diagram it has about 6 or so different taps on the transformer for 220, 440, single phase three phase 50cycles 60cycles. Manual is also in I think seven languages. But one of the points it does make is that you must be sure to connect the power leads to the correct taps. Mine came from the company with the 220 cord and plug no problem. I assume that yours came from the dealer with the correct cord and plug as well. I wonder though if they connected the cord to the correct taps if yous is likewise made for the world market.

Video is at http://www.canadianmilitarypattern.com/CMP%20Videos.htm bottom of the page.

Cheers Phil

[Bob Carriere]

...if I left my spot welder ON that long I would melt a hole to China....

Your is behaving like what I would expect and what I have seen in sheet metal fabricating plants......

Either something is wrong with my Unit or it is wired wrong.....

Can't wait to take it back to the dealer and have the sale rep try it out.... which will also check it out from a different power source.

The Miller came with a standard 15 amp 220 volt plug which is like a 110 plug except both spades are flat like two _ * _ the asterisk being the ground prong...... I had to build an adapter section using 24 inches of 10 gauge 3 wire rubber cable.... it has a female outlet in a metal box and the other end is wired to a standard 220 large welder 50 amp plug..... which in turn is plugged in a commercial 25 foot 220 extension cord which I use regularly with the Mig welder......

This is no good with out pictures..... will try a photo shot tomorrow evening if the political hassle at work does not keep me in til 6:30 like tonight.

???? how large are your tips contact area in the first samples....??

I am using the specified pointed/tappered coppe tips at 3/16 wide at the contact area.

Man this is frustrating....... particularly when the teckkie from Miller suggests using a long extension cord to drop the amperage.... ????

Bob

[Phil Waterman]

Hi Bob-

I'll comment on the rest of the e-mail a little later. But could not resist commenting on ".... particularly when the teckkie from Miller suggests using a long extension cord to drop the amperage.... ????" did he give you any idea of how long the cord should be? Or around whose neck it should be coiled? If it had been the salesmen saying this the answer would be easy how far to the next sales district.

If every thing is wired correctly on your unit sounds like you should be able to spot weld two sheets of 1/4 inch plate. As to reducing the amperage how about a big a variack would you need?

Tips in the first image is 15/32nds rounded these seem to last well and are less critical of miss alignment. The funny U shape tip unit is for welding fender lips they are cone shape with a flat that start off new at 1/8th but fairly quickly flatten/burnoff down to 13/64ths when they seem to stay constant and weld well for a long time. I only use the fancy shaped tips on auto sheet metal which use a fairly low power setting and time. For most if not all the CMP spots I'm using the round tip as they can take the heat and just don't seem to wear/flatten/burnoff. I'll try to post some more still photos and detail explanation on my site let you know when they are up.

[Bob Carriere]

Finally connected with the Miller sales rep this afternoon.

As can be expected I was totally "humidated" when he showed me how it worked.........

First for the tickness I was using..... it is not explained in the miller manual.... the copper tips of the are toooooo small a surface area and burn holes..... tips brand new are meant to fit the low amperage 110 and the 220 spot welders...... the tips are about 1/8 new... they need to be burned down... or filed down to 3/16 to a 1/4 inch wide.......

Next issue...... they told me I was using too much pressure.... in fact even when I was first using it I was not using enough pressure.... again the manual says.... do not pressure too much or copper rods will bend......

Well it seems that with good decent pressure.... enough to hold, compress, and see some flex in the copper rods....... you Zap the switch for a slow second and....voila..... very good welds.

I even simulated the door skin combination..... one 40 thou (19 gauge + -)
plus one 14 gauge (for the door frame) and one more 19 guage for the door skin fold over...... about 4.2mm.... and perfect welds all the way through the 3 pieces with very little surface damage.

....and this 3 layers were done without readjusting/lowering the pressure to account for the extra thickness of the 3 parts. Only difference I kept the switch on for about an extra 1/2 second...... total 1 1/2 sec.

They have recommended using a flat surface tip for the lower electrode when doing the good side of door skins.

Left with a smile..... now I know how it works and free new tips.

In time I will experiment with using a perfectly spherical copper tip as opposed to pointed to see if it will work for me as suggested by Phil W. As soon as I get a tip too worn out.......

Now the proof is in the puddin' or the doing the practice, practice, practice...

Thanks for all the help, support, comments, suggestions.....hope it can be of some help to others.

Boob

[Phil Waterman]

Hi Bob

Glad to hear you are now going to be able to use what is a really handy tool. Now the next step is to look at the original 60 year old CMP spot welds and file your tips so they will match the shape of the original worn tips used in producing the truck in the first place.

Keep us posted on any trick you learn now.

Cheers Phil

[RHClarke]

Originally Posted by Bob Carriere

Finally connected with the Miller sales rep this afternoon... In time I will experiment with using a perfectly spherical copper tip as opposed to pointed to see if it will work for me as suggested by Phil W. As soon as I get a tip too worn out...Now the proof is in the puddin' or the doing the practice, practice, practice....Thanks for all the help, support, comments, suggestions.....hope it can be of some help to others. Boob

Bob, Feel free to try welding up a few of the one gal POW can holders - they are in the barn attic (the can is on the wooden shelf nearby). Congrats on sucking it up and going to the experts for help (we were running out of scrap test metal).

[Stewart Loy]

Originally Posted by Bob Carriere

Now the proof is in the puddin' or the doing the practice, practice, practice...

Boob

Bob,

Save some pudding for me!


Stewart