Learnin' The Ropes (A Thread for Newbie Scratch Builders)

[Tailwinds]

I just picked up one of those frequently loathed $100 Harbor Freight gasless flux wire welders, I do not know how to use it. I have never welded but I do not fear it. I'll get some practice over the next several days. I also scored one of those auto-darkening helmets on the cheap, My neighbor, awesome guy, brought over a smock, 2 pairs of thick leather gloves w/ extra long cuffs, another helmet, and a pair of pliers specifically designed for welders. He does not have a welder so he's hoping the gifts will get him a free pass to welder-ville, it will.

I already have a bunch of odds and ends to work on, BUT, in the long run I would like to be able to do so much as to add new tubes to existing frames, say, do gender changes on girls bikes, I have too many of those frames. So, a couple of simple questions. WHERE do you guys get tubing from? I read somewhere that it's nearly impossible these days.
Also, I have a drill press, if I were to get a couple of hole saws for cutting the tubing, which sizes would you get?

So, to recap, where do I get tubing? And, what size hole saws would you buy to cut the tubing?

 

[Uncle Stretch]

I already have a bunch of odds and ends to work on, BUT, in the long run I would like to be able to do so much as to add new tubes to existing frames, say, do gender changes on girls bikes, I have too many of those frames. So, a couple of simple questions. WHERE do you guys get tubing from? I read somewhere that it's nearly impossible these days.
Also, I have a drill press, if I were to get a couple of hole saws for cutting the tubing, which sizes would you get?

So, to recap, where do I get tubing? And, what size hole saws would you buy to cut the tubing?[/quote]





On the term Scratch Built , it refers to when you take a bunch of tubing and build a frame complete.

Most steel companies have a pretty good selection of tubing. Its pretty much standard sizes. Like 1'' 1 1/4'' 1 1/2'' They may have others too. I buy 20' sections of 1 1/2'' 18 gauge , for about $20. They cut in half free. On the hole saw , The only reason you would need one is to get the radius to fit one tube against another. Then you would buy the size of the tubing you were using.

 

[jerrykr]

make a run to Home Depot and get a couple of 1 inch wide x 1/8 inch flat stock steel strips.

cut into pieces 3 - 4 inches long.

Lay them side by side on something non flamable, with about a 1/16 - 1/8 inch gap between them, and practice running a bead welding them together. remember to tack both ends before you start the bead.

Then try some steel strips the same thickness as the tubing. thin stuff is a lot harder than something 1/8 inch thick.

practice.

once you get that down, get some tubing and practice with the round pieces. An old junk frame cut up would be perfect.

welding around the tubing is also a lot harder than flat stock lying right in front of you.

practice more, you will get it.

get a small disk grinder with wire brush and grinding disks to clean up your welds. get a cutoff disk to use to cut the tubing unless you have access to a chop saw. Harbor Frieght cheapies will do until you go pro.

have fun and good luck!

 

[Tailwinds]

The only reason you would need one is to get the radius to fit one tube against another. Then you would buy the size of the tubing you were using.

Do you not radius the tubing?

 

[stretch]

you could radius the tubing with something other than a hole saw, like a couple cuts to make a v shape at the end, that works good too.

 

[X-RAY]

if your neighbor had that stuff, id bet he also knows how to use it and could show you some tricks. my question is, is the welder ok for a beginer, or should a fellow save up for a better mig? ive heard a few bad things about flux-core, but maybe new stuff is better. i really dont know, and i was gonna ask tonite anyhow, so im just "borrowing" this thread. 8)

 

[bigredddaddy]

For radious fitting tube together I hack-saw a "V" and then use a barrel shaped carbite drill bit to "fish-mouth" the end and check fit it as I go. I've also used my 4" angle grinder to do the same. Also a vice is realy useful to hold your tube, or a piece of wood and a C-clamp on the end of your work bench. I use one of those $100 welders too and it welds pretty good but I find it's not so great at tacking parts together. It is a 110v and may not have the amps at the start to get the heat. I have a propane torch that I'll heat up the spot to tack first, it's better than the 5-7 trys before a tack finaly holds. A flux-wire welder is smokey so a fan is a good thing. Welp your on your way and as my welding instructor said,"Burn 'n Learn"!

 

[Tailwinds]

if your neighbor had that stuff, id bet he also knows how to use it and could show you some tricks. my question is, is the welder ok for a beginer, or should a fellow save up for a better mig? ive heard a few bad things about flux-core, but maybe new stuff is better. i really dont know, and i was gonna ask tonite anyhow, so im just "borrowing" this thread. 8)

Long story, my neighbor used to work at a place that did tons of welding, so, I think all that stuff came home with him unnoticed. He used it when the previous owner of the house I now own had a welder, and he's admitted repeatedly that he's a terrible welder.

That crappy HF flux wire feed welder was 87 bucks. That's a price I could justify to see if welding is a good fit for me. In a couple more years I'll part with the $450 for that ohh-so-nice Hobart 140 if I find that welding suits me.

Still haven't tried it yet.... Been busy renovating a couple of closets in the house.

 

[X-RAY]

i didnt mean to insult you or your welder, and i apologize if it came out that way. ive been interested in one myself, and you cant beat that price. the guys ive been talking to havent used anything flux core recently, so maybe their opinions are based on early versions that maybe werent as good? or maybe they dont like anything but their expensive stuff. one guy told me flux core wasnt strong enough for the stress a bike frame goes through. i see lots built that way here, so im all kinds of confused. i actually am thinking of doin just like you, if i like it upgrade later on. just lookin for some more input first.
again, im sorry if i offended anyone.

 

[Chainsaw]

If you ask a professional welder, 9 times outta 10 they'll you that flux core is junk, it won't hold together or something else that is negative. For starting out or for those who only have a 110 system, those cheap or inexpensive flux core welders are ideal. Many of the guys started out and sometimes stayed with a flux core. And many of them have one of the Harbor Freight versions!

I build various styles of bikes, I wiegh around 300 lbs. and I suck at welding but my bikes hold together about 99% of the time and I ride them for years. The couple of times my bikes have broke, it wasn't at the weld.

I've met several welders who thrive on complaining about other people's welding abilities or they constantly complain about the equipment. And ALL welders usually blame their own crappy welds on the equipment they're using, no matter how cheap or expensive it may be! It's never their fault. :lol:

Flux core isn't as clean as gas mig but then it's not as expensive either! If you're a good welder then you're a good welder, if you're crappy you're crappy .... the results will pretty much be the same no matter how much money you drop!

I use a 110v Harbor Frieght flux core and it suits it's purpose, but eventually I'll move and get a 220 gas mig, probably Miller. Don't complain about what you've got, be thankful you got it. A lot of the guys on this board don't even have a welder and are envious!

 

[scrumblero]

as far as the quality of flux core welds, this is what Lincoln has to say..

A 115 volt flux-cored machine using an electrode such as .035" Innershield NR-211-MP will generally allow you to weld steel up to ¼"thick. Note that this is more than double the thickness maximum of 12 gauge with MIG on 115 volts.

 

[Tailwinds]

i didnt mean to insult you or your welder, and i apologize if it came out that way. ive been interested in one myself, and you cant beat that price. the guys ive been talking to havent used anything flux core recently, so maybe their opinions are based on early versions that maybe werent as good? or maybe they dont like anything but their expensive stuff. one guy told me flux core wasnt strong enough for the stress a bike frame goes through. i see lots built that way here, so im all kinds of confused. i actually am thinking of doin just like you, if i like it upgrade later on. just lookin for some more input first.
again, im sorry if i offended anyone.

No offense taken, not in the slightest, but thank you.

 

[Uncle Stretch]

I'm pretty sure that a 220 welder will get hotter than a 110 welder. If your going to weld thick stuff together, you can go past the limitations of a 110 welder, and they also have a duty cycle. It means you can't take off welding a bead and go forever. The higher its set the less time it will weld. As far as flux core wire vs regular wire and gas , I think the only difference would be the slag left by flux core will be eliminated if you use gas. I have welded lots of stuff together in the last 20 years I have had my Miller 110 flux core welder and never had anything break. Not cars...not bike frames...nothing. If I want to build a trailer out of thick angle , I will go back to my stick weld cracker box. Saying flux core is bad , would be like saying the flux on the rods for stick welding will make for a weak weld. NOT!

 

[outskirtscustoms]

I've done a few custom jobs in my old days and one trick I have learned that will save a little coin and get you by when doing tube fitting. Kinda Redneck ingenuity at it's finest but it works well.

Step 1: Go to the local gas station and grab a handful of coffee straws.
Step 2: Place the straws around the tube that needs to be fitted and wrap a rubber band around them
Step 3: Hold tube in place where you want it and slide each straw down till it just touches where you need to weld it
Step 4: Now grab the whole mess of straws and slide them all up the tube till the last straw is on the edge of the tube
Step 5: Trace the outline of the straws onto the pipe with a marker, take over to the bench grinder and grind to the line, you'll at least be close, a little test fitting and adjusting will be required.

They do make a specialty tool that works off the same principal but it's rather expensive and only works on one size pipe. Not to mention the $40-$50 EACH price tag.

Hope this helps :mrgreen:

 

[bigredddaddy]

Who says flux-core is week? A few years back, I bought a 4 door Corsica to run in the demo-derby and used my HF welder to weld 4X3 metal plates on the door seems,(2 each,12 total) and welded a 3X3 metal tube on the B pillars behind the seats. I took 2nd in the mid-size and the next weekend, my buddy from the junk-yard took it and got 1st at another derby. NONE of the welds broke and those plates at the back were bent up from the car's rear end being totaly smashed in, the welds wern't even cracked. Most derby guys use either stick or flux-wire 'cause they're cheap and get the job done. I do have my eye on a TIG welder but that little Speedway welder is not going anywhere!

 

[DougC]

Where to get tubing: if you want good tubing, then look in the phone book of the nearest big city for "metals suppliers". The kind that you want is 4130 steel. Call them up, explain that you want to build bicycle frames so they have some idea of the sizes you want, and ask them if they have any drops that you can look through. If they will not sell by the foot, then tubing usually comes in 20-24 foot lengths, or sometimes in half-lengths. A "drop" is the cut-off piece that is left over when somebody doesn't buy a whole length of tubing.

Mild steel tubing can work well also, but is not as good as 4130.

If you buy 4130 or mild steel tubing, the max wall thickness for a frame tube would be maybe 1/16" inch. A 110V welder probably wouldn't weld much thicker than that anyway.

Electrical conduit,,,,,,, is "something resembling the leftover material from a cow's digestive process". It is VERY weak and flimsy, and yet is still relatively heavy. And it is galvanized besides, which is bad for welding (zinc fumes are toxic). Can you use it? Yes, you can. But it is very, very, very far from ideal.

How to fishmouth tubing: there are free programs floating around online to do this, on various sites. A hole saw is not required, just a way to cut/grind/file the tubing. The IHPVA site has a couple listed on there somewhere, one is tubemiter.exe, also linked here- http://www.ozhpv.org.au/shed/tubemiter.htm .......this produces a diagram that you print out and tape around the tube end, and the printout will have an outline that you cut/grind to to get the fancy curved edge. It is not perfect (like using a real milling machine or fishmouther would be) but it is WAY cheaper than either of those, WAY better than guessing and WAY faster than trial-and-error fitting.

Brass/bronze brazing will produce a better join than welding will--but brazing requires better fit-up, and more expensive rods.

Aluminum is more difficult to work with successfully, particularly for building bicycle frames. Gas tanks and fenders you can try, but I'd suggest don't even try to build a frame yet. For gas tanks and fenders, you want 5052-alloy aluminum. 6061 is the common structural alloy, but thin sheet of 6061 will crack during cooling if you try to weld it. 5052 is softer and will not crack during cooling.
~

 

[Tailwinds]

That's all great advice! Thanks Doug!

 

[daniels]

I know this is an older thread but I'm a newb and just found it. LOL Just a FYI I have a Hobart EX125 flux core welder and it'll weld 1/4 inch thick steel without a problem. I welded 1/4" thick tow hooks for my old Subaru and it was a strong weld.

Here is a couple of things I welded with it. Nothing fancy at all but you'll get the idea that it can do more than 1/16" steel.

http://michiganmotorcycle.blogspot.com/ ... -tool.html

http://michiganmotorcycle.blogspot.com/ ... acket.html

Excuse the sloppy welds, it was when I first got the machine. LOL

Also, I've used a lot of different brands of wire and in my opinion the Hobart brand wire is by far the best. I have some Lincoln wire in the machine right now because I ran out mid project and had to run to Lowes and I don't like it at all.

 

[Tailwinds]

Ahhh, blast-from-the-past thread. So, since I started this back in November I have welded a few things. I find that the crappy Harbor Freight $87 flux core welder is indeed crappy, but somewhat usable. My only gripe is that is seems to expend most of its energy creating weld splatter and not doing much real work, which creates tons of work for me after the weld. Five minutes welding and fifty minutes cleaning up the weld, grinding, brushing, etc.

Seriously, I spent 3 hours welding that seatpost binder on and all of 10 minutes of it was actual welding, the rest was grinding and sanding.

Here's a before/after....

 

[daniels]

If you get the chance to use some Hobart wire I think you'll be surprised at the lack of splatter. I get a ton of splatter with the Lincoln welder I'm using now but almost zero with the Hobart.

Looking good man.