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kb2qqm
02-12-06, 10:10 AM
Anybody ever build a bike frame Electrical Conduit...
Is it strong enough. Someone mentioned to me not to use it as when welding it, the coating is toxic?
It will be used for a recumbent frame..
Greg

potus
02-12-06, 04:56 PM
yea, welding galvanized steel causes metal fume fever, not good. why not use 4130?

kb2qqm
02-12-06, 10:28 PM
I am a newbie. I am not building the frame. (Yet) A gentleman makes frames from 1 inch electrical conduit...
www.recycledrecumbent.com I am just getting started. I would like to learn to weld/braze.
I would also like to learn to weld at a school. bought the welding book by "Finch"...at home depot.
I travel alot (30K miles per month minimum)and not sure I have the time for going to school. I need someone to show me the "ropes" of welding. Safety first. Then I want to practice. I just don't want to buy a torch and "wing it".
I want to learn from someone one on one...
I have the will, so I am sure I will find a way. I will check out the 4130.

Thanks. Greg

atombikes
02-13-06, 08:06 AM
I am a newbie. I am not building the frame. (Yet) A gentleman makes frames from 1 inch electrical conduit...
www.recycledrecumbent.com I am just getting started. I would like to learn to weld/braze.
I would also like to learn to weld at a school. bought the welding book by "Finch"...at home depot.
I travel alot (30K miles per month minimum)and not sure I have the time for going to school. I need someone to show me the "ropes" of welding. Safety first. Then I want to practice. I just don't want to buy a torch and "wing it".
I want to learn from someone one on one...
I have the will, so I am sure I will find a way. I will check out the 4130.

Thanks. Greg
EMT (electrical conduit) does not have the yield strength necessary for frame construction. The website you reference does not use conduit for the entire frame; he uses 2 sections of 3/4" conduit for the 2 "connectors" between the bottom bracket and the chain stays in a toureasy clone frame. This is an acceptable use of conduit. Conduit is heavy and weak compared to comparablly-sized 4130.

In my opinion, you should get yourself a cheap mapp torch (bernzomatic model JTH7- this model has a 4 foot hose), and a bottle of mapp gas have have a go at brazing. This is a cheap way to get started, and if you decide that framebuilding isn't for you, you're not out alot of money.

The plans I offer on my website http://www.geocities.com/atombikes/plans offer a comprehensive look at building a front wheel drive recumbent lowracer. The plans tell you how to clean EMT to prep for brazing (I use EMT for the seat back frame), but I will tell you the trick here. Get some "Sno-Bowl" brand toilet cleaner, and dip the EMT in it for several minutes. It will eat the galvanizing off, leaving a totally clean tube. Of course, you can use this trick to prep any tube for brazing, just make sure you rinse with clean water, then dry and shine with emory cloth afterward.

MichaelW
02-13-06, 09:58 AM
zinc coating can vapourise at low brazing temps and find its way into your lungs where it is toxic. Check out the various hazardous materials sheets on the web.
If you need bike tubing then rescue an old frame from a skip. Just make sure it is not a collectable before chopping it up.

Peterpan1
02-13-06, 04:39 PM
You shouldn't use conduit for the safety reasons metioned also the zinc doesn't paint well. The welding Fever or damage to the brain is very serious and can't be taken lightly. Obviously this is an extreme case, but just to separate this instance of feamongering from those who say... butter is bad for you, this is closer to having Cheney as a hunting partner:

http://anvilfire.com/iForge/tutor/jd_fuller2/top_index.htm

Not to despare, youc an use non chromo just get some cheap erw. in 1/16" wall from any metal supply store. You can make whole bikes with it is going tohave to be a little heavier. Check out the atomic zombie guys they build alot of cool stuff with conduit scale tubes:

http://www.atomiczombie.com/forum/default.asp

You have to register to read, or you used to have to. Don't worry it's a safe enough forum.

Peterpan1
02-13-06, 04:41 PM
Or

http://2x4.xntrick.co.uk/

kb2qqm
02-14-06, 02:36 PM
Thanks for everyone's input. I am not sure what to do now. I might try the Mapp Gas deal and see what happens...I can always upgrade to an OXY set up. I have never welded or brazed, although I would love to learn, but I travel 30K miles per month and classes are out of the question right now. I think I could do well if someone took 2 hours and showed me the ropes..with gas..Thank you also for the info on the galvanized pipe. I have some plans coming in the mail...so I will have to decide what it is that will be built. Can someone send me some links of tubing manufacturers for 4130? Mail order or a local shop near Milwaukee.
Thanks..Greg

potus
02-14-06, 02:52 PM
Can someone send me some links of tubing manufacturers for 4130? Mail order or a local shop near Milwaukee.
Thanks..Greg

http://www.aircraftspruce.com/

.035" is a good thickness for bike tubes.

kb2qqm
02-14-06, 08:02 PM
tHANKS for the link...!

g

sngltrackdufus
02-15-06, 12:24 AM
yea, welding galvanized steel causes metal fume fever, not good. why not use 4130?
What is "metal fume fever"??

atombikes
02-15-06, 07:21 AM
Mail order or a local shop near Milwaukee.
Thanks..Greg
I'm pretty sure that the website owner that you first referenced (www.recycledrecumbent.com) is in the Milwaukee area? Check his contact info on the website. He may be willing to help you out.

rmfnla
02-15-06, 07:37 AM
Electrical conduit is intended to bend easily; is that a property you want your frame to posess?

I thought not...

tom porter
02-17-06, 09:39 AM
I have been building recumbents for 15 years, I use EMT for mesh seat frames for its cost and ease of bending;you have to remove the zinc coating in a well ventilated area such as a garage or outdoors. I've seen many frames built with muffler tubing which is mild steel and I believe 1/16" thick, its cheap and can be bent by a local muffler repair shop; there are some sites on the web doing this. I show some of my techiques on the WISIL site just look under the project pages.

Tom Porter

Proformance Cyc
02-18-06, 01:00 PM
Do you have the link or site address for WISIL?

TIA

LC

atombikes
02-20-06, 09:18 AM
Do you have the link or site address for WISIL?

TIA

LC
http://www.wisil.recumbents.com/wisil/

That should work.