Homebuilders.

[nutz4bikez]

Hey guys

Are any of you into building your own recumbents?

I have built a few now and love looking at the work of others so I hope you aren't shy about showing off your work.

I will be posting pics of some of mine as soon as I am allowed to.

[vic]

Yes indeed, I'm having a go at my first. A USS LWB made from other bikes. still in the parts accumulating stage. I have made a lowrider/chopper with 4 foot forks. Not sure if that qualifies as a recumbent..

In the process of painting it, but below `15 degrees and high humidity with a spray booth is prolonging the process. It might not be serious, but I'm having fun. Cheers.

[vonhazza]

Hi welcome to the group,
I haven't done a proper build yet but I have assembled a Cruzbike kit to my own frame and I am planning on doing a welding course soon so I can have a go at building.
I found some interesting build ideas at the Atomic Zombie site.

Regards Steve.

[Uba Tracker]

G'day Steve, forgive me if I come across as a know all, but if you want to invest the time in a welding course try and find one that gives you an intro into brazing. IMHO it is a far better process for bike building than say stick welding (MMAW) as it is rather detailed work and it's very easy to blast a hole through a frame tube with a stick. Plus brazing is more forgiving to repetitive stress than arc welding.

cheers

Harry

[vonhazza]

G'day Steve, forgive me if I come across as a know all, but if you want to invest the time in a welding course try and find one that gives you an intro into brazing. IMHO it is a far better process for bike building than say stick welding (MMAW) as it is rather detailed work and it's very easy to blast a hole through a frame tube with a stick. Plus brazing is more forgiving to repetitive stress than arc welding.

cheers

Harry

Hi Harry by all means stick your oar in, I read elsewhere in the forum that you have a great deal of experiance in welding and I am happy to receive any advice.

Steve.

[vic]

Seems to me that there is a fair bit of dissension about arc welding. I just want to add that the chopper is stick welded. Solid, and no holes. Equipment cheaper to buy.

[Uba Tracker]

Seems to me that there is a fair bit of dissension about arc welding. I just want to add that the chopper is stick welded. Solid, and no holes. Equipment cheaper to buy.

Hi Vic, great to hear that your experience with arc welding was a positive one, but you're right I should have balanced my comments by pointing out that arc welding is significantly cheaper in initial set up costs. To qualify what I said earlier it is my experience that arc welding presents more challenges to the inexperienced welder in terms of satisfying results than say the brazing process. No one should be discouraged from expanding their skill base so my apologies to all if I appeared 'anti' arc welding, by all means give it a go. Follow Steve's (Vonhazza) lead and do a welding course, you'll learn accepted practices and hopefully minimise the frustration that results in many a welder gathering dust.

regards

Harry

[toolonglegs]

Quick question on the brazing...I have never built a bicycle and never will.But I am a pretty good welder,mig,tig arc & gas,although I havent touched any welding equipment for nearly 10 years.Would you braze a bicycle frame without the use of lugs?...ie:sticking to tubes together without lugs.Is this strong enough if they are fitted together well enough?.

[John Lewis]

I'm building number 8 at the moment. Some of them can be seen in the "Show off Your Bent thread on page 2.

All of mine have been filet brazed with Oxy Acetylene except the first which was done with a gas air torch (Not recommended) Working on an Atomic Zombie Delta Wolf now and considering arc welding as that is what has ben done in the plans.

Be warned, building bikes is addictive.

John Lewis

[John Lewis]

Quick question on the brazing...I have never built a bicycle and never will.But I am a pretty good welder,mig,tig arc & gas,although I havent touched any welding equipment for nearly 10 years.Would you braze a bicycle frame without the use of lugs?...ie:sticking to tubes together without lugs.Is this strong enough if they are fitted together well enough?.

Hi Toolonglegs,

I believe fillet brazing is an acceptable and strong method for building bikes as an alternative to lugs. A lot of bikes have been built that way.

Certainly I have had no problems with the bents I have built and I've never had a welding lesson in my life.

John Lewis

[Cyclaholic]

Quick question on the brazing...I have never built a bicycle and never will.But I am a pretty good welder,mig,tig arc & gas,although I havent touched any welding equipment for nearly 10 years.Would you braze a bicycle frame without the use of lugs?...ie:sticking to tubes together without lugs.Is this strong enough if they are fitted together well enough?.

Personally I think synergic pulse MIG would be a good option for a steel frame, if you have the equipment. I'm thinking about having a crack at a lowracer frame since I have enough bits in the parts bin, and a decent MIG machine.

[Uba Tracker]

Quick question on the brazing...I have never built a bicycle and never will.But I am a pretty good welder,mig,tig arc & gas,although I havent touched any welding equipment for nearly 10 years.Would you braze a bicycle frame without the use of lugs?...ie:sticking to tubes together without lugs.Is this strong enough if they are fitted together well enough?.

Is it strong enough - yes, but it's a conditional yes. John mentioned fillet brazing, which in essence is controlling the deposition rate of filler rod by the heat input. Too much heat and the brass will 'wick' away from the joint area following the increasing heat in the surrounding frame. Too little heat and the brass wont 'wet' in to the joint giving adequate adhesion. The use of tubular gusseting is widely used particularly where the top tube meets the steerer tube, use that method in any area where you feel a butt joint is inadequate and you'll be right. Lugs are great though, especially in mass production as it allows the entire frame to be loosely assembled before clamping and brazeing.
Toolonglegs you hinted at my all time favourite process, T.I.G. (GTAW) if you are experienced in the art then I would recommend that you forego all other methods and run with that, it is unreservedly the best process. The great thing about T.I.G. welding (for steel frames not alu) is that nowadays it's not much more expensive to set up than arc welding, get yourself a nice little D.C. inverter plus your torch and gas control gear and you could be set up for under $500 AUD which is about half what it was three years ago.

regards

Harry

[toolonglegs]

Cheers guys,just interested thats all.Although maybee with the amount of frames I go thru it might not be a bad idea!.

[vic]

Hi Vic, great to hear that your experience with arc welding was a positive one, but you're right I should have balanced my comments by pointing out that arc welding is significantly cheaper in initial set up costs. To qualify what I said earlier it is my experience that arc welding presents more challenges to the inexperienced welder in terms of satisfying results than say the brazing process. No one should be discouraged from expanding their skill base so my apologies to all if I appeared 'anti' arc welding, by all means give it a go. Follow Steve's (Vonhazza) lead and do a welding course, you'll learn accepted practices and hopefully minimise the frustration that results in many a welder gathering dust.

regards

Harry

No worries Harry, I agree. You can rest assured that as soon as I have stashed away enough change, I will get me a mig. Cheers

[Ricco]

I have built several recumbents all with arc welding.

Low budget stuff, and guess that is the point, half the fun realy is making something that some would charge you an arm and a leg for, you get to try something out for very little cost.

Tig etc. would be nice, but have had only one failure with arc. That was outside my house on a fork I tried to modified that I thought probably was'nt going to be strong enough, I was right. Nearly had a kitten when it broke, even though I was expecting it.

Current version uses a bottom bracket and forks from uprights and all other bits are custom made, welded and ground. Including the stem of the forks. I taught myself to weld.

Not always pretty, generally lots of grinding if pretty is a factor. Though have made some stuff that even I did not think was possible.

Have fun, nearly forgot I always employ the jump test or something similar. Put thing of the ground supported between two pieces of wood and step on it, be realistic here, if you can flex the metal around the joint then most likely it will hold up.

Take care, explore, enjoy!

[antipathyincarnate]

Hi there

I guess my choppers are recumbents. We're about to have a go at a production version. We're happy to take advice or have extra people come on board to help.

Don

I can't post the link but if you'd like to see them just drop me a line

[Recycler]

Howdy All,
Here is some more information on stick welders, I have found the best rods I use are marked for Mild & Medium Tensile Steels E 6012 2mm. On a Inverter welder I use about 45 amps. Long Live Stick Welders

[vic]

Hey guys

Are any of you into building your own recumbents?

I have built a few now and love looking at the work of others so I hope you aren't shy about showing off your work.

I will be posting pics of some of mine as soon as I am allowed to.

Got any piccys yet?

[Uba Tracker]

Howdy All,
Here is some more information on stick welders, I have found the best rods I use are marked for Mild & Medium Tensile Steels E 6012 2mm. On a Inverter welder I use about 45 amps. Long Live Stick Welders

Hey there Bob, yeah good advice the 6012's are a very versatile electrode. Just for everyones info the breakdown of the classification E6012 goes like this. 'E' stands for electrode (no prizes there), the '60' is the tensile strength of the weld deposit in Mpa's (megapascals) and the '12' denotes the composition of the flux, the '12' designation means a reasonably fluid flux or slag whilst welding suitable for most downhand or horizontal welding. Personally I like the Lincoln 4113's or 6013's, the '13' in this case denotes a more viscous slag whilst welding making it more suitable for positional work (vertical up, overhead etc) where the more stable slag can aid in the control of the molten weld pool.

cheers all

Harry

[Freddyflatfoot]

Hmm, might check to see what I'm using!
I found that the Cigweld 1.6mm rods have been the best for me, for welding light gauge steel. Still need to be careful to not get too much heat into the work though!
I'll have a look in the shed before I go to work shortly.

[Uba Tracker]

Hmm, might check to see what I'm using!
I found that the Cigweld 1.6mm rods have been the best for me, for welding light gauge steel. Still need to be careful to not get too much heat into the work though!
I'll have a look in the shed before I go to work shortly.

Hi Rob, I wouldn't stress too much about the class of electrode you are using, particularly if you getting good results. I'm sure you're aware of the adage,"Don't fix it if ain't broke." As far as electrode classification goes it is my experience that electrode quality far out-weighs the small difference between the classes, so the upshot is buy name brand good quality rods and you'll be right.

cheers

H

[JulianEdgar]

I don't think that anyone has mentioned using flux coated nickel bronze brazing rods. I use them (plus oxy acetylene of course) on chrome moly tube, building up only small fillet. Very strong and pretty easy to do.

[Gecko Racer]

Just about to start on my third HPV. 1st was a practice, 2nd became a race bike for the children at my school and this one hopefully will be a little lighter and more streamlined to help us go faster than we have in the past. Looking to incorporate Chromoly for the roll bars and side intrusion but will continue to use mild steel (school chairs and desk frames) for the frame. This fits in with our intent to recycle and allows the children to have some ownership of the process.
I have used a MIG so far and this seems to work fine on the mild steel but my research leads me to think that Brazing may be more effective for the Chromoly. Having no experience with this I would appreciate any helpful advice.

Cheers

[papa]

Unlike like MIG or stick, oxy-gas is similar to TIG in many respects - torch in one hand, filler in the other. And like TIG, the beauty of gas, is that you have full and complete control over heat input and filler quantity from beginning to end. Brazing chromoly isn't any different than mild steel as long as you abide by the basics with proper pre-brazing preparation and don't char the flux. I prefer paste flux and bare rod because it allows me to coat all surfaces prior to adding heat - this helps to prevent premature oxidation.

The coupon sample shown below was brazed with generic, 64kpsi tensile LFB (the cheap stuff) and Harris (Black) paste flux. It was extremely rusty 1/4" thick mild steel (ground to .200"), and the fillet was done in a single, 15 second pass using a Victor #4 tip fed with propane and oxygen. The sample was then allowed to cool and bent in an AWS coupon bender.



And by simply attaching a smaller tip on the very same torch, you can silver solder 2mm stainless spokes:

[John Lewis]

G'day papa,
Seem to recall meeting you on another forum. If I remember right you were using an ex medical oxygen generator. If I'm correct, would you mind giving a few details about it and how you find it. I have my sights on one but don't know much about their use.

John Lewis