I realize I need the neck tube and crank tube already threaded but what about the other tubes? What kind of steel does it have to be? Can I just go to my metal supplier and get it? I'm interested in making my own frame for my next build. Any help would be great. I have mig and DC Tig. I will practice with both on some scrap before welding it up so not sure what I'd use yet.
what kind of tube to weld frames?
- Thread starter Henry Sanchez
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Depends what you want in the bike...
You can get away with plain mild steel seamed tubing, this is what most lower-end frames are made from these days anyway. (recommend 16 gauge wall)
You can also step up to DOM tubing from most steel suppliers.
High tensile tube is pretty cheap and matches most Mig wire for tensile strength, that is what I personally like to use, most suppliers will have, or can get it in for you, but you may have to buy in full lengths.
CroMoly is available from speciality suppliers usually, good if you want to go lighter wall and therefore lighter bike, but then you will be better off with the Tig to weld it up.
If you really want to go cheap, even old recycled fence pipe can be used, just sand the galvanising off first... It will be a heavy bike, but great for the beginner welder (easily weldable with even the very cheapest stick machine) or those with very strict budgets.
Luke.
You can get away with plain mild steel seamed tubing, this is what most lower-end frames are made from these days anyway. (recommend 16 gauge wall)
You can also step up to DOM tubing from most steel suppliers.
High tensile tube is pretty cheap and matches most Mig wire for tensile strength, that is what I personally like to use, most suppliers will have, or can get it in for you, but you may have to buy in full lengths.
CroMoly is available from speciality suppliers usually, good if you want to go lighter wall and therefore lighter bike, but then you will be better off with the Tig to weld it up.
If you really want to go cheap, even old recycled fence pipe can be used, just sand the galvanising off first... It will be a heavy bike, but great for the beginner welder (easily weldable with even the very cheapest stick machine) or those with very strict budgets.
Luke.
thanks. that helps a lot. I've found another thread on head sets and the part that holds the crank. So if I were to get those already tapped what kind of metal are those usually in? I imagine there's not much option for that.
Do you mean cutting them out of donor bikes or ordering them from somewhere like Paragon?
Pretty sure most of the builders on here remove them from donor bikes, in which case they are normally either mild steel ERW or High-tensile. If you want Chro-Moly you would be checking what the bike is tagged as.
Try here if you decide to go new: http://www.paragonmachineworks.com/cgi-bin/commerce.cgi?search=action&category=0001
Just be aware that ordering the pieces can add up really quick, while donor frames for cutting up can usually be had for free or under $5 and can sometimes provide some tubing too...
Much cheaper for first attempts, in case things don't work out the way you want...Luke.
Rat Rod
Owner & Founder
Here are some good posts to read on welding...
http://www.ratrodbikes.com/forum/in...-tube-size-to-build-a-bike.10372/#post-125311
http://www.ratrodbikes.com/forum/index.php?threads/welding-tip.72267
http://www.ratrodbikes.com/forum/index.php?threads/welding-equip.19957/
http://www.ratrodbikes.com/forum/index.php?threads/how-i-stretch-a-frame.19866
http://www.ratrodbikes.com/forum/in...-tube-size-to-build-a-bike.10372/#post-125311
http://www.ratrodbikes.com/forum/index.php?threads/welding-tip.72267
http://www.ratrodbikes.com/forum/index.php?threads/welding-equip.19957/
http://www.ratrodbikes.com/forum/index.php?threads/how-i-stretch-a-frame.19866
thanks so much guys. I think I'll go to the swap meet this weekend and look on Craigslist. In the meantime I'll look into differing sizes of head sets and crack holders(not sure of the name) so I know what to look for when getting donor bikes.
Bottom Brackets.
We shorthand that to "BB."Two main sizes, the normal American 1 piece (BMX/Vintage Cruiser) and the smaller threaded 3 piece. (MTB/Road/Some modern Cruiser)
Headtubes will differ considerably in length, so try to find a bike with a fork you can use and use the matching headtube with it, also available in two main sizes: 1" threaded, (Older bikes) and 1.25" threadless that require the clamp on type stem. (Most newer bikes)
As always there are exceptions to the rules on both, as you look at more bikes you will be able to tell easily what they are and what parts are worth saving.
Luke.
tomorrow I'm gonna go to the metal supplier where I get my sheet metal and plan to look for some mild steel (16 gage wall) as you recommended. I also plan on getting a cheap tube notcher to fish mouth the ends and a hole saw bit. So my last question before I go get metal is the size of the tubing. I'm assuming 1" is common size? Should I go for that or is it a big deal to go 1 1/4" to keep it the same size with the head tube? I'm still in the dark about common head tubes but would want a bike like those modern cruisers where the frame matches the shape of the tire and is low to the ground. The ones with beefy rims and beefy forks. They seem pretty common and would like to make one of those style bikes. So I'm assuming I need the smaller BB for the threaded 3 piece? and also the 1 1/4" head tubes for the the beefy forks? Thanks for all the info btw. Anyhow, this weekend I will get the tubing for the bike and focus on my Tig/ mig welding on some scrap to get my "roll of dimes" technique better. I will probably get a cheap notcher and hole saw bit to simulate a real frame. I'll worry about getting the bb, head tubes later.
A handy hint for you, grab the headtube out of a frame and buy your tubing the same O.D. that way you can make your front triangle on any flat surface and all the tubes will line up nice and straight.
Luke.
Luke.
thanks guys. so when you see all those fabbed frames for the low beach cruisers where the frame conforms to the tires, what are those usually? Are those usually 1" or 1 1/4"? Are mountain bikes a good bike to look for the bb and head tubes for that style of bike?
ok, so it seems like the forks and head tubing length would be a huge issue. So on this ad below it says 26"x4" for fat tires it says. What indicates the length of the head tube ? Would that be "axle space"? Or is that the space for the wheel axle? Or are these adjustable to the head tube? Man, there's so much to learn. I haven't even considered the bearing race...oh boy! It also states it's 1" thread less, which that seems to have been answered already by Luke. Just trying to make sense of all this. Sorry for the stupid questions. I owe this site big time for all the knowledge.
http://www.ebay.com/itm/26-x-4-0-Triple-Tree-Fat-wheel-Tire-BICYCLE-Fork-1-threadless-w-Disc-Tab-Chrome/331490828514?_trksid=p2141725.c100338.m3726&_trkparms=aid=222007&algo=SIC.MBE&ao=1&asc=20141212152715&meid=7c22bdeb3901471c936f9b05bf00d5aa&pid=100338&rk=6&rkt=29&sd=331490825405
http://www.ebay.com/itm/26-x-4-0-Triple-Tree-Fat-wheel-Tire-BICYCLE-Fork-1-threadless-w-Disc-Tab-Chrome/331490828514?_trksid=p2141725.c100338.m3726&_trkparms=aid=222007&algo=SIC.MBE&ao=1&asc=20141212152715&meid=7c22bdeb3901471c936f9b05bf00d5aa&pid=100338&rk=6&rkt=29&sd=331490825405
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ok, I see most bikes that could be donor bikes are the thread less type. I have already watched a video to remove the the head set and re install so I can get the frame flat on the ground to weld it flat. Then I will use a protractor to ensure everything is straight leading the rear wheels, or maybe make a jig. I really wanted to make a cruiser with big fat 4" wide tires but then I'd have to buy a Mongoose and butcher it up and use the rims and BB/head set. So after looking at my OCC schwinn, I can see the BB width needs to widen with the rims and hubs you choose. The rear wheels on my OCC Schwinn are 4" and the BB is 4.75"/120mm wide, is there a rule of thumb in regards in order to pick the right BB for the width of rims you want? I see it's 3/4" bigger than 4" but not sure if there's a formula for that.
If you decide to go the route of an OCC build I may have some stuff that might interest you. I have a frame that is trashed,I could cut the bottom bracket shell and headtube from it . I also have the wheels,etc.
Most of the parts are there . These parts have some rust, etc...not perfect. Just a thought.
Most of the parts are there . These parts have some rust, etc...not perfect. Just a thought.
You will be doing well to find a cheap frame to cut up that will have the BB to work with 4" wheels...
Luke.
so is there a formula for figuring out how wide the BB should be or do you just go after bikes that have them and are made with the BB meant for that rim size?
I think for my first frame I'll just use whatever I can find and later do the 4" wheels on a different bike.
thanks but I can't find a cheap way to get those rims/hubs unless I buy a fat tire bike, and they have the BB already. I really appreciate it though
I have widened bottom brackets and crank axles in the past to suit wider rims, and will be happy to help with that if you get to it, but better to stay with known parts for your first couple of builds!
Luke.
