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Rubens
12-15-2012, 06:43 PM
Hello,

I posted this under another thread but I think it might deserve it's own.
I am shopping around for a welder. I learned to weld using an arc welder years ago but I haven't done it for quite some time now.
Budget and lack of proper electrical installation are pushing me to one of those 120V, 70A units (something like this: http://www.princessauto.com/mobile/p...ductID=8169385 (http://www.princessauto.com/mobile/product/productDetail.jsp?productID=8169385)).
So my question is: can I build bikes with it?
Thanks!

Radical Brad
12-15-2012, 08:02 PM
others here have used these 120v welders with great success. I used one once and found it worked well, but there were more false starts (sticking).

Brad

trikeman
12-15-2012, 08:38 PM
I think if it were me, I would find a cheap used Lincoln or Miller stick welder on Craigslist. The big welders make things easier because they just have more ooomph, but they do require 230v. Failing that, I would also look into one of the little 80A inverter welders that Harbor Freight sells (not sure about Canada). I've never used on of the inverter welders but several members here have.

http://www.harborfreight.com/80-amp-inverter-arc-welder-91110.html

http://www.youtube.com/watch?v=bujvEHMcnEE

Rubens
12-15-2012, 09:45 PM
Thanks Brad and trikeman,
Well, it is possible to find an used Lincoln AC-225 within a 100km radius from where a live for around $200 (which wouldn't be too much off my budget). However, the biggest problem is to have a 230v/50A outlet available to hook it up. The dryer or the stove plugs I currently have are rated 230V but 40A max. Even if I decide to try the 40A, it's hard to find an extension cord rated at that current (I believe they do exist but have no idea how much they would cost).
The electrician I consulted would charge some $300 (material included) to connect a 230V/50A line from the electrical panel in the basement up to my garage.

Rubens
12-15-2012, 09:48 PM
I haven't heard of those 80A inverters before. They look interesting. I will see if I can find a distributor up here.
Thanks.

Radical Brad
12-15-2012, 09:56 PM
Remember, that a 40a requirement is rated for full output at 225 amps. You will probably never push past 100a until you weld material over 1/4 thick.
Although I would recommend against doing so, the following will prove my point...

When I first setup my 225a AC welder, I ran a standard length of interior house wire all the way from the garage and into a makeshift stove plug, where I ran both 120v poles into the hot and neutral, feeding 240 volts all the way back to my welder on wire that is normally used for 15 amp connections. I unplugged it when not welding, but did this for 2 years. In fact, every bike from the original Bike Bonanza book (including Marauder V1) were made using this makeshift connection. There was of course a voltage drop, so a 75a setting on the welder dial was more like 65a. Oh, and a year after that, I did the same 240 split hack using just a hardware store extension cord!

So, don't worry about temporarily plugging your welder into a stove or dryer socket, it will be just fine. Purchase a proper length of 240v 40a wire and it will work perfectly without any voltage drop. Much less $$$ than a real welder capable extension cord. Either way, never leave such a rig plugged in after you are done using the welder.

Brad

TexasTuff
12-15-2012, 10:30 PM
I get along fine with my 120v 70a wire feed. I just finished welding my Brush Hog back together. Took 2 days but I got it done. Even on 10 ga or 12 ga I hit it with the grinder and put a little bevel on it before welding.

Rubens
12-15-2012, 11:28 PM
True. Operating at half that max power would drain half the amps...
You've made a good point there, Brad. I guess I should not discard the 240V unit yet :-)
Thanks again, guys.
Rubens


Remember, that a 40a requirement is rated for full output at 225 amps. You will probably never push past 100a until you weld material over 1/4 thick.
Although I would recommend against doing so, the following will prove my point...

When I first setup my 225a AC welder, I ran a standard length of interior house wire all the way from the garage and into a makeshift stove plug, where I ran both 120v poles into the hot and neutral, feeding 240 volts all the way back to my welder on wire that is normally used for 15 amp connections. I unplugged it when not welding, but did this for 2 years. In fact, every bike from the original Bike Bonanza book (including Marauder V1) were made using this makeshift connection. There was of course a voltage drop, so a 75a setting on the welder dial was more like 65a. Oh, and a year after that, I did the same 240 split hack using just a hardware store extension cord!

So, don't worry about temporarily plugging your welder into a stove or dryer socket, it will be just fine. Purchase a proper length of 240v 40a wire and it will work perfectly without any voltage drop. Much less $$$ than a real welder capable extension cord. Either way, never leave such a rig plugged in after you are done using the welder.

Brad

trikeman
12-16-2012, 08:19 AM
Since I sold my MIG a few years ago, I am down to only one 230V welder (my ancient Miller Thunderbolt AC/DC) and my beloved oxy-acetylene rig. . I have always run the 230v welders off my 40A dryer outlet using a 50 foot extension cord I built by buying a 30A 110v recreational vehicle cord (made to connect to RVs to the power source when camping) and cutting the ends off and replacing them with 230 v connectors. I think I paid $30 at Harbor Freight for the cord, and probably $10-$15 each for the connectors. Its been a number of years so don't hold me to those prices.

I run the cord out the window of my utility room and weld in the backyard with the Thunderbolt. As Brad says, you will probably never crank it up above 100 Amps on the welding side, which means it won't draw more than about 20A on the house side. The cord has never even gotten very warm, since I don't tend to weld hours at a time. There are not enough welds on a bicycle to even warm up a good welder. I did once crank it up all the way just to see what cutting 1/4" plate was like with it - that was exciting if you like lots of sparks and smoke and a sound like a jet engine lol. Miller says to use a 50A breaker on the Thunderbolt, but I have never thrown the 40A breaker, and as I say the 30A cord seems to work fine. If I did overload the 30A cord for long enough, I suppose it would smoke it, so I used to keep an eye on it just to make sure. Obviously, if you do this, the risk is your own.

If you do decide to go with a 110v welder be sure you have a good circuit to hook it to. I started out with a Hobart Handler 110V wire feeder. It was a good welder, but the circuit in my garage was so weak, I was never happy with it. When I finally hooked it to a circuit right next to my mains junction box, it was like a different welder. I think a lot of the blame for people who aren't happy with 110V welders goes to to-small wiring in their houses. People probably don't all have good 230v wiring either, but there is so much power available from a 230v outlet, that it doesn't matter as much.

trikeman
12-16-2012, 09:05 AM
By the way, if you do decide to go with one of the little 80A inverter welders, Freddy and others that have used it seem to recommend that you use the smaller 1/16" rods with it, rather than the 3/32 rods.

http://forum.atomiczombie.com/search.php?searchid=412392

sandman
12-16-2012, 01:04 PM
Hello,

I posted this under another thread but I think it might deserve it's own.
I am shopping around for a welder. I learned to weld using an arc welder years ago but I haven't done it for quite some time now.
Budget and lack of proper electrical installation are pushing me to one of those 120V, 70A units (something like this: http://www.princessauto.com/mobile/p...ductID=8169385 (http://www.princessauto.com/mobile/product/productDetail.jsp?productID=8169385)).
So my question is: can I build bikes with it?
Thanks!
Hi , my answer has to be yes, with 16swg rods more than enough, and if you want to weld thicker metals than 16 or 14 gauge then there is a method call vertical up welding, a bit tricky but it allows thicker materiels to be welded with low amps, in fact it needs low amps or you blow holes,theres always more than one way to skin a cat and correct rod/flux coating plays a big part, some rods strike easily others need pushing into the weld to maintain an arc, the bottom line is yes it will be fine but as Brad said, you might get rods stuck and have a porcupine for a bit, its not the end of the world, every journey starts with a first step and if we fall over thats all part of that learning experience, waffled on too much
good luck
john

Rubens
12-16-2012, 10:24 PM
Thanks guys for all those invaluable inputs.
Good to hear from your experiences about this and they will definitely help me make a more informed decision when buying my welder.
Cheers,
Rubens

Tradetek
12-17-2012, 12:19 AM
If you go with a 110/120v model, you should also check the AMP rating on your Plug Receptacle, in addition to the circuit breaker.

My garage had a Receptacle that was only rated for 15 AMPs, on a Circuit Breaker rated at 15 AMPs, but the wiring my house is all 20 AMP wiring, and some circuits in the house had 20 AMP breakers where I know that I didn't need them, so I swapped my breakers around, and got a 20 AMP GFCI Receptacle and increased the capacity of my TIG. Interestingly enough, my brothers MIG would not weld on the same circuit...

Rubens
12-23-2012, 12:24 AM
Brad,
I was looking at the streetfox project and the axle mounting tabs are made from 2x 1/4" tabs welded together. What was your welder setup (amps) to weld those 1/4" pieces? Perhaps this is something the 120V welder can't handle?

Ticktock
12-23-2012, 06:59 AM
Should be no problem--just make more than one run to fill the Vee--but get rid of the slag on each pass.
Steve G

Rubens
12-31-2012, 06:24 PM
Hello again,
I ended up buying this one: http://www.canadiantire.ca/AST/browse/6/Tools/WeldingSoldering/Welders/PRD~0588193P/Mastercraft+Arc+Stick+Welder.jsp?locale=en
I gave it a try in the last couple of days and I've noticed that setting it up to min amps (50A) and using the 6013 1/16" rods, I can generate an arc easy to maintain. However, with 6013, 3/32" rods and max amps (70A) it is very hard to maintain the arc, sticking all the time.
Maybe the 70A is not enough for those 3/32" rods?
Thanks in advance and Happy New Year.

trikeman
12-31-2012, 10:22 PM
Rubens - that is pretty consistent with the results in FreddyTK's YT videos with the little Harbor Freight inverter. It just didn't have enough uumph to keep the larger rods going, but worked fine with the 1/16" ones. Its probably not that 70A isn't enough for the 3/32" rods, but rather that your welder may be able to put out 70A for a few miliseconds, but cant' sustain it. The open circuit voltage is probably enough to start the arc, but once a lot of current starts flowing, the voltage drop in the small windings have a pretty large voltage drop and take away from your voltage to the arc. That's why heavy duty welders weigh hundreds of pounds (lots of big low resistance copper wire) and small inexpensive ones don't weigh much. I'd just keep using the small rods.

trikeman
12-31-2012, 11:11 PM
It could also be that you are not connected to a strong enough circuit on the 120 side. As I have said before, puny household wiring is the bane of these little welders.

Rubens
01-01-2013, 12:59 AM
Thanks for your help, trikeman.

When I went to get those 6013, 3/32" rods, I noticed that the 6011 3/32" beside had a lower amperage range (something like 40 - 80 A). I was wondering whether worth giving them a try?
Another burning question would be whether I can have reliable (I mean strong) welds using 1/16" rods...

trikeman
01-01-2013, 01:05 AM
As a general rule, you don't need a rod thicker than the metal you are welding. To make Brad's bikes, you are generally going to be using 16ga tubing, which is very close to 1/16" thick. People weld really thick metal all the time by making multiple passes, but for our work here, you will probably never need to do it.

Putting a big fat weld on thin metal doesn't make anything stronger, because once you exceed the thickness of the parent metal by a whole lot, you are just wasting rod, and creating more warpage and alignment problems, assuming you have full penetration.

trikeman
01-01-2013, 01:38 AM
By the way, one of the best bargains in arc welding books is called, "The Procedure Handbook of Arc Welding." It was published by Lincoln and you can pick up old copies off eBay for between $5 and $10. My version is about 700 pages and was published in May of 2000 (first copyright 1934), but these things don't change much.

trikeman
01-01-2013, 02:49 AM
6011 rods are designed to give higher penetration than 6013 rods. The higher amp rating of the 6013 means it melts the rod faster, and you have to move along faster, but with lower penetration. The 6011 being a slower burning rod (less amps) gives it time to really dig in and achieve deep penetration.

For welding thin metal, such as 16ga zombie sized tubing, penetration is not your biggest problem - burning through is. Therefore 6011 rods are not really your best bet.

There are a lot of rods all designed with different characteristics, for different jobs. Unfortunately most of them don't come in 1/16 size so with a 110v arc welder you will probably have to stick to the the standard rods, such as 6011, 6013, etc. One of the easiest rods for beginners is 7018 which flows like butter and is very easy to light and keep lit. Another advantage of 3/32 rods is that they are much more common and therefore usually cheaper.

Rubens
01-01-2013, 11:21 AM
Thanks, trikeman.
I will burn more 1/16" rods today trying to move from straight beads of yesterday to join few pieces together. Let's see how things go.
Cheers,
Rubens

trikeman
01-01-2013, 11:29 AM
Thanks, trikeman.
I will burn more 1/16" rods today trying to move from straight beads of yesterday to join few pieces together. Let's see how things go.
Cheers,
Rubens

Don't be shy about posting some pictures of your welds. They won't be pretty, but we have all been there. We can probably give you some pointers about your technique etc from looking at your weld pictures.

Rubens
01-01-2013, 11:50 AM
Very nice, trikeman! That was very helpful.
I will post the pictures.... Thanks for offering to check them out.
Cheers.

Rubens
01-01-2013, 04:39 PM
Hi,
Here goes the first picture.This is my attempt to make a straight bead.
The whole thing is about 5" long and consumed an entire 1/16" 6013 rod. The welder was set to 50A.
Any thoughts? Thanks!
5891

richl
01-01-2013, 05:11 PM
Go much slower. Spend as much time as you can concentrating on the puddle (the very bright red spot in the area of the rod when it hits the metal). As you understand that and can see what it is doing the rest will become more obvious.

Lots of videos on the web to help you understand what that is and why it is important. Youtube is a treasure trove of info.

Keep going, they will only get better.

Rich

trikeman
01-01-2013, 05:12 PM
Doesn't look too bad for a first weld. Obviously you did some stopping and starting and either didn't chalk a line to follow, or had trouble following a line. its best when showing pictures of the welds to clean it off wheel with a wire brush, so you can see how well the sides tied into the base metal. How many amps were you running, and how thick is the metal?

Once you master following a line, the real test will come when you try to weld two pieces together. Leave about a 1/16" gap between them to ensure good penetration.

I think the hardest part of welding is training yourself to see and watch the puddle. not the bright light. Could you see the puddle ok with these first welds? Some rods have more flux on them than others, and that and the smoke and flash can make it hard to see what is going on.

richl
01-01-2013, 05:19 PM
Another thing to use as a reference, if your rod is red or very hot to the touch, you might need to turn the amps down.

Rich

trikeman
01-01-2013, 05:21 PM
I have this guys videos on arc welding.

http://www.weldingvideos.com/arcwelding1.html

They were very useful when I first started out because they helped me to know the puddle was supposed to look like and what it meant to control it. There a several videos o YT that show you what the puddle looks like, as well.

Rubens
01-01-2013, 06:40 PM
Thanks for the comments guys.
Rich, the rods didn't appear to be too hot...
Trikeman, I used 6013, 1/16" rods with my welder set to 50A (min. amperage - the max. is 70A). The metal bar is mild steel 1/8" thick. I was trying to follow an imaginary chalk line :-)
I am now browsing youtube for videos on arc welding...

trikeman
01-01-2013, 07:41 PM
If you flip the piece over, you can get some sense of penetration by observing whether any of the metal on the bottom appears to have melted (or at least gotten close). If not crank that puppy up all the way and as Richl says, going slower on that 1/8" metal. The only way you are gonna get complete penetration on 1/8" steel with that few amps is if you bevel the steel and do more than one pass.

Imaginary chalk lines never worked for me. I have a hard enough time seeing the real ones made with my welding marker.

Rubens
01-02-2013, 03:32 PM
Hi,
After another round of welds, this is my most recent bead (still using 1/16", 6013 rods on the 1/8" steel bar):
5896
I tried to slow down and wave the rod around a little bit following a line. It looks a slightly more uniform to me but I'd like you guys to please comment on it.
Thanks!

richl
01-02-2013, 04:01 PM
Excellent! 1000% better, the penetration seems to vary but you are getting something down that looks like a good solid start now. Keep at it, you will only keep getting better!
The bead that you laid down to the far righ, looks like 2-3" furthest right is what you want to aim for, it appears to be getting decent penetration. What setting did you finally use for that section?

Rich

trikeman
01-02-2013, 04:01 PM
The line definitely helped. Its looking better. I wouldn't worry too much about whipping the rod around too much right now. It looks like you started and stopped a few times. Did you intend to do that? If you want a continuous weld over the whole piece, you have to start close to where you stopped, and then move back to tie the last bead in before you go on. However, I can't remember any welds on AZ bikes that were longer than a few inches anyway. This is very good practice.

I agree with Richl that the last few inches looks 1000% better than your first welds.

Once you start welding two pieces together you will have to concentrate on moving the rod side to side to and watching the puddle to make sure you are getting penetration on both pieces, but that is the next step. Are you still using only 50 A?

Rubens
01-02-2013, 04:24 PM
Thanks guys!

I kept the welder at 50A during all these runs. The difference between left and right beads is that I tried to move slower on the latter. I tried to make both without stopping (which turned out to be harder than I thought).
One thing I noticed is that the 1/16" electrode consumes very fast (one is good for about 4" long bead).

richl
01-02-2013, 04:35 PM
What Trikeman says is good advise. For me, I would just keep practicing with that rod, on that metal for as long as you can, once you understand how to strike an arc and run the bead and control the puddle with 6013 on 1/8" steel, you will have a solid reference point for other rods, metals and welding positions. You picked this up too quick! :)

Good Luck!

Rich

trikeman
01-02-2013, 04:43 PM
Yeah, that 4" max with those 1/16" rods does make it kind of hard not to stop and start, but as I said, fortunately AZ bikes usually don't have any long welds anyway.

Rubens
01-02-2013, 04:50 PM
Thanks again for all the support, guys.
I will keep welding with the current setup and see if I can get more control over the bead.
One question: on my last picture, the right hand side bead looked with a deeper penetration because it looks 'flatter' ?

richl
01-02-2013, 05:03 PM
Ok, I'll leave it at flatter :), the rings you see are close together, they are flowing uniformly in one direction and the edges appear to be penetrating into the steel you are welding to. There are more technical ways to say that :) but I leave that for others to describe. You want things to be uniform: the width, the height, and the weld marks (rings).

trikeman
01-02-2013, 05:03 PM
There are other things that can make a weld bead flat, including moving too fast, having too steep and angle, etc, but its usually a good sign.

Once you start welding two pieces together, we will most likely ask you to cut through the bead on a perpendicular, polish up the weld a bit and see how much penetration you are getting. What does the other side of your steel look like?

Rubens
01-02-2013, 05:08 PM
Hmm. Hard to say how the other side of the steel is like as it is covered with welds as well :-)
I will do this again on another area of the bar that I can flip over and check on the back.
Thanks

darnthedog
01-03-2013, 08:47 AM
Another think you can do to verify your penetration is to cut the bar across the weld to see how well it is attached. I had to do this when I first started as my beeds start looking good. But was warned by a welding instructor to cut one of my beads to check it. Needless to say they did not actual melt the base metal. So be sure to do a cross cut to check out how well your penetrating the metal. The goal is to melt the base to form a new whole. That way it will be one piece instead of two attac hed pieces. I used Flux core mig to start out with. So I had no comment on your bead till now. They look good but just a bit of warning the make sure your getting good penetration. One Zombie on here had a bad weld on a Maraduer I believe and went riding when the Steering tube separated from the main boom. Fortunately he was not injured. So be sure of your penetration. Your looking good from the top side just keep on praticing.

Rubens
01-03-2013, 06:36 PM
Once you start welding two pieces together you will have to concentrate on moving the rod side to side to and watching the puddle to make sure you are getting penetration on both pieces, but that is the next step. Are you still using only 50 A?

I tried 70A today (using the 1/16" rod) just to see how it goes. By moving the rod at same speed I blew a small hole on that 1/8" steel bar. Also, after some time I tripped the circuit breaker and in my garage :-)
So it appears that the combination 50A + 1/16" rods is working better, at least for that 1/8" steel.

Rubens
01-04-2013, 11:06 PM
Yeah, that 4" max with those 1/16" rods does make it kind of hard not to stop and start, but as I said, fortunately AZ bikes usually don't have any long welds anyway.

I did more training on those 1/16" rods @ 50A today. I'm feeling more comfortable and in control of the thing...
The fact that I have to hold the welding mask with my other hand doesn't help :-) (perhaps investing in an auto-darkening helmet in the future)
A bit more training and I will venture into welding pieces together. Let's see...

I was wondering whether worth trying 5/64 rods @ 50A ?

Thanks.

Rubens

trikeman
01-04-2013, 11:22 PM
Whatever money you were going to spend on 5/64 rods, spend it on a auto-darkening helmet that you don't have to hold with one hand. Its essential that get as comfortable as you can be to do make nice welds. I can't even imagine trying to weld with a hand-held helmet. Once you get a helmet, you will be able to hold the stinger with both hands and get yourself steady.

Rubens
01-06-2013, 04:02 PM
Trikeman, I followed your advice and bought an auto-darkening helmet (pretty good deal as it was on sale). Wow, what a difference it makes! It is one less thing to worry about not having to hold that mask...

Taking advantage of my new toy, I tried I new exercise by joining two pieces together. Basically, I just took that 1/8" steel bar shown in previous pictures and cut it in two. Using the same setup: 1/16", 6013 rods @ 50A, I made the bead shown in the next two pictures (views from top and at an angle).
59545955
I'm showing the electrode here too to have an idea of scale. As I was laying the bead, I had to move the rod side-to-side to fill the gap. I tried to move slowly. Now I think that perhaps I should have slowed down even further as it appears the penetration hasn't been complete (please see next pic from taken from the other side).
5956
Any comment is appreciated!
TIA,

Rubens

trikeman
01-06-2013, 04:32 PM
Glad the helmet is working out.

The flatness of your weld in picture #2 suggests to me that you may be using too steep and angle (almost vertical). Almost vertical angles do help penetration some, but will not build up a nice weld bead with 6013. You probably need to start with something more like 45-60 degrees to let the rod build up some weld.

Here is some advice from ChuckE2009 on that

http://www.youtube.com/watch?v=Z2B36psoNQ4


That said, I think you are finding out that 50 A is probably not enough to fully penetrate that 1/8" steel in one pass, unless you bevel the joint. Try grinding a bevel on both sides so you can reach he bottom of the V and give it a go. You could also, of course crank up the amps to about 60, assuming your rod is rated for that.

If beveling the edges, turning up the amps a bit, and going a bit slower doesn't' do it, you may have to bevel both sides of your steel and weld the back and front.

Fortunately, this may be the thickest steel you will ever need to weld building bicycles. Its all good experience. There is no substitute for burning a lot of rod. I have said here in years past that I learned more about welding burning through (and watching the steels color and behavior) and patching it up, than I ever did just laying easy beads. Its pretty easy to lay down a pretty bead on top of a piece of metal, and get very little penetration, especially with a MIG welder. Professional welders sometimes refer to those as "Lawyers' Welds,' Its more difficult to get a pretty bead on top and full penetration.

Can you see the puddle? Rather than just weaving side-to-side you should be able to see the metal melting and tieing in on both sides, and not moving on until you do. Seeing the puddle is really the secret of all good welding.

Some people find value in counting how long they stay on a side before crossing back over, something like "one thousand one, one thousand two, crossover slowly, one thousand one, one thousand two, cross back over" etc.

Good work - you are getting there.

Rubens
01-06-2013, 09:10 PM
The flatness of your weld in picture #2 suggests to me that you may be using too steep and angle (almost vertical).


I got it. I will work on the angle.



That said, I think you are finding out that 50 A is probably not enough to fully penetrate that 1/8" steel in one pass, unless you bevel the joint. Try grinding a bevel on both sides so you can reach he bottom of the V and give it a go. You could also, of course crank up the amps to about 60, assuming your rod is rated for that.

If beveling the edges, turning up the amps a bit, and going a bit slower doesn't' do it, you may have to bevel both sides of your steel and weld the back and front.



The 1/16" 6013 rods I have are rated 20 - 45A. My welder is very limited as it offers only two settings for amperage: 50 and 70. I will bevel the edges, though, and see how it goes.



Can you see the puddle? Rather than just weaving side-to-side you should be able to see the metal melting and tieing in on both sides, and not moving on until you do. Seeing the puddle is really the secret of all good welding.

Some people find value in counting how long they stay on a side before crossing back over, something like "one thousand one, one thousand two, crossover slowly, one thousand one, one thousand two, cross back over" etc.


Yeah, I think I'm making the beginners mistake of rushing things... I have slowed down in comparison of what I was doing before but I think that it needs to go even slower...



Good work - you are getting there.

Thanks for your support and patience, man.

trikeman
01-06-2013, 10:43 PM
When I first started welding I had a little Hobart wire feeder. I always felt like the darn thing was rushing me, so I moved too fast. All that wire pouring out, and piling up in my mind, etc. etc. A fast burning rod can make you feel the same way. Its important not to let it rush you. Don't start moving until you see that puddle as wide and as molten as you want it. Can you make it bigger, can you make it smaller. Can you make too excited, or calm it down. Then don't worry too much about where you are going right now. Instead, concentrate on controlling that puddle and moving it around. Try to bun some holes n the metal and watch the puddle and surrounding steel closely. Learn to recognize what molten steel in and around that puddle looks like and what it looks like when its about to burn through. Its tempting to watch the arc - don't do it, its the puddle you want to watch. Look at the back and sides of the puddle to see how it is melting into the base. If you can become master of the puddle, the rest is easier.

Rubens
01-06-2013, 11:32 PM
Very true. I have the feeling that if I don't move the rod away, that puddle thing will become some kind of China Syndrome...
I will focus more on taming that puddle in my next runs.

You are right about a fast consuming rod: it appears all the time that, if not moved, the entire rod will dissipate in a single small puddle. The fact that 1/16" rods cost about 50% more than, say, a 3/32" does not help with that :-)

Cheers

Rubens
01-09-2013, 11:51 PM
Hello,
I did some more training tonight on 1/8" steel plates.
Although laying beads on the flat part is becoming easier with time, I noticed that a T join with two plates looks terrible.
I tried to drag the rod the same way (very slowly and at a angle) I was doing on the flat bar but there's no way I could have a nice bead. The beads looked lumpy and with the slag very hard to remove. Is this an indication that I need more amps (still using 1/16" rods @ 50A)? Or does it mean I'm running a longer arc (because of the T joint corner)?
TIA,
Rubens

richl
01-10-2013, 12:04 AM
By T joint are you referring to 2 pieces of metal laying flat and you are creating a butt seam (flat weld between the 2 pieces)? I think you said you welder only has 2 settings 50 and 70 amp? If you did what TT suggested by cutting a nice bevel on each piece, try slower. If you have more adjustments, try to go up 5 amps. Another choice, though it starts to get sticky here, a smaller rod will allow for more of what amps you have to get thru the rod to the weld area.
If none of those fork, you could always practice a T joint where the 2 pieces are perpendicular to each other, that should be easier to do, and should work at a similar setting.

When in doubt, show us a picture, it sometimes is easier to see what is happening, for me anyway, I learned the ole school way, in the field :)

Rich

trikeman
01-10-2013, 12:41 AM
T-Joints are more difficult than simple butt joints for many reasons. First you are trying to get the weld bead down into a 90 degree angle, while still concentrating on making sure both sides get melted. Second, that side sticking up is a great radiator of heat, so you have to angle the rod a bit down let the heat rise. There is a lot of slag with 6013, so you really have to concentrate on seeing the puddle and making sure you pause long enough on both sides to get fusion. In other words you are going to have weave back and forth between both sides and pause long enough.

You are also trying to weld 1/8" metal with a small rod, and you may not have enough heat to do it in one pass. You say you are dragging the rod, but 6013 really likes to have about an 1/16 to 1/8 gap off the metal.

There are a lot of variables here, so its tough to say exactly what you are doing wrong from the description.

Rubens
01-10-2013, 12:43 AM
Sorry, I should be more specific, the "T" joint I meant is actually 2 flat bars perpendicular to each other.
Yes, my welder has two settings for amperage: 50 or 70. I have been working with 1/16" rods @50A. This is actually a bit higher than the rated amperage range for it: 20 - 45A.

Rubens
01-10-2013, 01:00 AM
Thanks for the comments, guys.
All makes sense. I will give it another shot trying to heat up that joint. One thing that concerns me, though, if it's that welder is actually maintaining the 50A throughout my runs... Sometimes, I have the impression that, from bead to bead, the welder behaves differently with the slag getting harder to remove and a bit 'porous'.

trikeman
01-10-2013, 01:13 AM
Part of the reason the welds are porous is because slag is getting trapped in the weld. That is why you usually need to slant the rod and push the slag out with 6013. Unfortunately, on a T-joint with a small welder you may have to go almost head on into the joint to get enough heat in one pass. You are really pushing the limits of this small welder trying to do those 1/8" T joints with 1/16" rods in one pass. You could always try some 6010 again on this joint, since it cuts deeper and has a lot less slag.

Rubens
01-10-2013, 01:21 AM
Got it. I will try it again with the suggestions in mind. Then I will take a picture with the one I consider my best bead. Thanks again!

richl
01-10-2013, 09:30 AM
I have no experience with this personally, but I have read this on a couple of different sources. The HF (consider this any of the lower end China made welders) models of welders tend to fluxciate temp and amps they output, especially after periods of use. This may be part of the reason you are noticing a difference in the consistency of the welds. Typically this is not a problem for many novice welders, they just are so overwhelmed with all of the other things they need to watch for and control they do not yet understand the welder and its effect on the operation also.

Rich

Rubens
01-26-2013, 06:50 PM
Hello,
After a 2 week hiatus (life's got in the way...) I have resumed my welding training. This time, I decided to try my cheap 120V welder on a 16ga steel tube (since that's what I'd expect to see most of the time). I bought some scrap 1 1/2" 16ga mild steel tube and set the welder to 50A using 6013 1/16" rods. In my first run I joined two pieces (pics below) and the joint looks, to me at least, better than my previous attempts with the 1/8" flat plates.
Thanks,
60696070

trikeman
01-26-2013, 08:54 PM
That looks pretty good considering how long you have been at it. Welding round tube is more difficult than a flat piece, because you have to keep moving around the pipe. Now that you are welding something your welder can easily handle, I think it won't be long before you are making great welds.

richl
01-26-2013, 09:15 PM
think in terms of just tacking 3-4 spots evenly spaced around the tube. than go in to fill in later, that will give you less distortion in the metal.


rich

Rubens
01-27-2013, 12:46 AM
Thanks for the comments, guys.
The way I approached this was to make two tacks at opposite sides and then went on to fill the gaps. I'll try add more tacks along the diameter next time.
Yeah, I think the combination :

50A on the welder ;
1/16" 6013 rods;
16ga steel;

Might be the best for me at this point (all things considered). It gives me a 20% duty cycle and the 15A/120V receptacle in my garage can handle it w/o tripping the breaker. Hopefully, I won't need to deviate much from this configuration when I finally start building bikes....

richl
01-27-2013, 07:21 AM
arc welding thinned walled round tubing is not a trivial task, it takes a good deal of practice. i've seen skilled certified welders who did not know how (mostly due to lack of exposure to this type of material). you are well on your way!

darnthedog
01-27-2013, 08:05 AM
Welds do look like your getting there. Two things to remember- Wire brush vigorously after each stopping to get rid of flux from rod. The grinder is your friend. It makes even the newest welder look pretty good. Another hint. to keep from over grinding your welds you can use a flap disc instead. But that is only if your budget allows for them as they get expensive if you use them in place of a grind wheel.
Good job.

Rubens
01-27-2013, 11:20 PM
I ventured a bit further with those 16ga tubes and welded them at a 90 degree angle. I did the fishmouth cut (used the tubemiter to get the template) and tried to maintain the 90 degree as much as possible (which I was able to do).
60796080
I also used the grinder to help with the looks :-)
I realize there's a lot to be improved but I am feeling more confident as I lay more beads and get the hang of the equipment.
Thanks for all the support you guys have generously giving.
Cheers,
Rubens

richl
01-28-2013, 04:49 PM
Another tool to consider, If you have a decent sized air compressor (20 gallon and up, and at least a couple of horse power) Air die grinders are a *** send for round tubing, I have both air and an old craftsman electric I purchased 20-30 years ago, they really allow you to get in and cleanup the welded area without doing the damage that the flap disks and angle grinders will do.

As always, my suggestions all depend on your budget and the amount of money and time you want to throw into this hobby :D

HTH

Rich

Rubens
02-18-2013, 08:26 PM
Hi folks,

After some more training on mild steel 1/16" round tubes I decided to take few old bike frame tubes and build another frame for a new commuter.
Among those bike tubes I used a very thin-walled 32mm diameter Chromoly steel tube. Using my arc welder amperage setup to its minimum of 50A and 1/16" 6013 rods, I tried to weld that tube and, to my dismay, it blows a hole through it the moment the arc starts (please see pic below).
6258
The really annoying thing is that it doesn't even need to get really hot to blow holes. I tried to put the welder clamp a bit away from the area attempting to reduce the amperage, tried to give it a quick pass, wait until the tube is again cold, etc, but nothing worked.

Any ideas?

Thanks a lot.

richl
02-19-2013, 09:56 AM
What is the difference between this tubing and the tubing you were welding in post #66?
If this tubing is thinner, stick with the heavier tubing.
The welder not having many ranges to work with is a disadvantage for you... there are a couple of things for you to try though. I used to use a 220v Lincoln Tombstone welder back some 30 plus years ago... some of the things I would try to get better ranges
more cable, adding resistance by adding more cable will decrease the amperage that is in the arc
try a bigger rod, it will not transfer the amperage to the metal as well, that may help.
Another technique I have been having some luck with on the mig welder is to use a series of very quick tacks onto the weld area. This technique will only work if you are at least close to the amperage you need to be.
The one that will more than likely work for you is just using heavier tubing. The other techniques are offered as things to try..

HTH

Rich

Rubens
02-19-2013, 08:35 PM
The tube in that picture is thinner than the one I was practicing. I don't know its specs but I measured his thickness as approx. 1.1 mm whereas the tube in post #66 is 1/16".
Also, the 1/16" was a scrap piece of mild steel I got from my steel supplier. The thinner tube is a chromoly from a donor bike.

richl
02-19-2013, 09:29 PM
The tube in that picture is thinner than the one I was practicing. I don't know its specs but I measured his thickness as approx. 1.1 mm whereas the tube in post #66 is 1/16".
Also, the 1/16" was a scrap piece of mild steel I got from my steel supplier. The thinner tube is a chromoly from a donor bike.

according to a google search, 1.1mm comes to about 18ga... thats pretty thin especially for an arc welder with 2 coarse adjustments. You could play around with some of the things I mentioned or invert a couple of your own... but you would probably be better served to use 1/16" tubing and make your new cruiser from that.

If you are looking for some ideas bikecad has a neat online source for plans in their database archives, there are some cool designs in there that might give you some inspiration, they come with measurements also. Take the head tube and bb from the donor bike and have some fun.

HTH

Rich

Rubens
02-20-2013, 12:55 AM
Thanks, Rich.
I will give it another try with some combination of those suggestions. Let's see how that goes...

trikeman
02-20-2013, 05:35 PM
Yeah - 50A is really too much for 18Ga metal. You could try a very low penetration rod, such as a 7018, if you haven't already.

Rubens
02-21-2013, 01:00 AM
Well, I guess I don't have much choice while I'm stuck with that welder other than try a few tricks (or use a thicker tube). At any rate, I think I should stop by the steel supplier and buy few feets of the 16ga mild steel tube just in case...

richl
02-21-2013, 04:32 AM
Well, I guess I don't have much choice while I'm stuck with that welder other than try a few tricks (or use a thicker tube). At any rate, I think I should stop by the steel supplier and buy few feets of the 16ga mild steel tube just in case...

With a heavy ga tube, you can weld a thinner tube to it, you will use a weaving motion, concentrating your weld on the heavy ga and quickly weaving into the thinner tube. It works well and I am sure you will be able to pick it up quickly... You would be better with all 16 ga tubing, but it is good to experiment. Little by little I am sure you will find some tricks along the way that will help you cheat, we all do :)

Something else that may work for you, if you have another tube that can fit inside the the one you are going to weld, you only need a small piece at the weld area, this will help the metal from the top piece from melting under the amperage of the weld.

Try different size rods, bigger always worked for me, though it is always iffy. 7018 is great rod, melts like butter, pretty, clean welds... but the rod absorbs moisture and decomposes quickly if stored over long periods of time... so either use it up quickly ( a couple of months or so) or buy smaller quantities of it...

Hope some of this is helpful

Rich

bovax
02-21-2013, 03:36 PM
Somewhat related question:
when welding what is the difference between zigzag motion and a whirly motion of the electrode?
6293

Rubens
02-26-2013, 09:42 PM
Hello,

Over the last weekend I tried some of the tricks (couldn't find a 7018 rod, though) but had to resort to the thicker 16ga tube in order to finish this. Thank you all for those tips!

Anyway, I somehow managed to weld the frame together now. It is not entirely finished as I preferred to leave some joints tacked while I have everything double-checked (something I learned here :-)). I'm glad I did that now since the head tube looks a bit misaligned with respect to the rest of the frame (I made a picture to illustrate this):
6337
The angle of the head tube (in red) is exaggerated in this picture, but when you carefully look at the frame from the head tube, you can notice the slight misalignment.
So I'd like to know how you guys guarantee the alignment of the frame, assuming no jig is used?

Thanks again.

richl
02-27-2013, 07:27 AM
Rubens, I am not sure you can "guarantee" it being right without a jig. But a jig does not have to be something big and time consuming thing to make. I have built a couple of dt bicycles over the last couple of months with a very simple jig I put together from an old aluminum ladder and some aluminum tubing I had around the shop. I have seen a number of easy to make jigs that were nothing more than a few 2x4's and some axles to hold the front and rear dropouts.63466347
So a jig can be as simple as the first image, or more complex like the second image.
With downtube bikes you can also do it another way, if you have a flat surface to assemble the bike on before you start welding things and the frame is just a single tube, ignore the front and rear forks for now, assemble the top tube, the dt, and the seat tubes on the flat surface than tack them up solid, as long as all the tubes are the same size this system works very well (Headtube, Downtube, seat tubes should all be the same size or you have to shim the thinner tubes).
So you can put the front fork on the bike and lock the front and rear to a straight board in a straight line, than it is just a matter of using sight and a straight edge of some type...
Others may do it different, that is something I have seen many others doing and is working for me.

To help you with your situation, use a straight edge have the bike frame secure so that it does not move (preferrable in a jig, but you use your best judgement), place one end of the straight edge on the top of the seat tube where the seat stem goes in, tha follow the top tube across to the top of the head tube, if all 3 tubes are the same size they will all hit the edge of your guage, now slide the side that is against the head tube down so that it gos to the bottom of the head tube, there should be no air space, all tubes should hit the guage. This does not guarantee perfect alignment, but it should get you pretty close.

HTH

Rich

trikeman
02-27-2013, 09:40 AM
Rubens - I mispoke when I said you should find some 7018. What I really meant was 7014, which you can get a pack of at Harbor Freight in 1/16" size. They really do melt easy.