Let's try this again.

[Locutus]

(I originally posted the questions shown below here in the Ask Us section, and it was immediately moved to the Tourmaster section. But no one has responded so I'm trying it here again. Hopefully this will generate some discussion.)

Copied text:

I downloaded the TourMaster plans today and have a few questions I hope you can answer:

1. In the photos it looks like you are using galvanized conduit. Don't you need to remove the galvanic coating prior to welding? If so, what is the best removal method?

2. After studying the plans for a bit, it appears to me that you really only need one donor bike if you use a bit more conduit and some smaller diameter hardware store tubing for the seatback brace. I don't think the idler pulley needs a second BB--another method of attachment could be used for that. So that only leaves the second head tube for the handlebars. I think an alternative to scrapping an entire bike frame just for the head tube could be figured out. A narrower suspension rear end could be substituted, which would also eliminate the need to cut up the rear end. The seatback brace could then simply be bolted to the panier attachment holes. Am I missing something here? Is there some reason that makes chopping up two frames necessary?

3. Now for a more ignorant question: What is the difference between "standard" 26 inch wheels and 700c wheels? Might either be used?

4. I'd like to use a new/newish donor bike with decent hardware to build the TourMaster. But it seems that all the better new bikes have aluminum frames these days. Which brings me to welding aluminum. What's your recommendation in light of this trend? Have a professional TIG welder do the aluminum welding for me after I cut and jig the frame parts? Buy a scrap steel bike just for the frame and part out a new aluminum framed bike without using the aluminum frame?

5. Would it be worthwhile to upgrade to disc brakes for the TourMaster? For me the intended use is a 42-mile round trip daily commute in wet or dry weather, some low hills, and dark early mornings.

[trikeman]

Sorry no one answered your original post. I will give it a try.

1. After an excursion into using Muriatic acid to remove the zinc from galvanized tubing, I eventually decided it was just easier to hit it with my flap disk on my angle grinder. I have also been known to just hold my breath when I weld it.

2. Someone else will have to answer that one. Judging simply from the pictures of the Tradewinds, it appears the front wheel (20"?) is smaller than the rear(26"?). Thus, you need a front fork and tire of a different size than the rear triangle and tire.

3. A 700cc rim is about 2" bigger in diameter than a 26" rim. It should create no real problems in the build (although you may have to adjust the frame a bit, which is a normal part of the building process anyway since the front fork and tire you use will be slightly different than the one Brad used in the plans). I think it is harder to find wide tires in the 700cc size, if that is your desire. I have no trouble finding skinny 1" tires for my 700cc road bike, but am running 2.25" tires on my 26" beach cruisers. About everything you could hope to know about tire and wheel sizes was answered by Sheldon Brown at http://sheldonbrown.com/tire-sizing.html

4. Welding Aluminum is more difficult that welding steel, and requires more sophisticated equipment. I have never heard Brad recommend aluminum in the year and a half I have been here, usually because he likes simple welders the average guy can afford, and is concerned over aluminum's propensity to fail suddenly and the need for post welding heat treatment. At least one of our members (OddManOut) is very happy with aluminum. There is currently an active thread running on the topic. Most of us just scrounge up a few old mountain bike donor bikes at the thrift store or beside the road. Craigslist is sometimes also a good source.

5. Disc brakes are always a nice option, especially with a heavily laden bike like a tandem on hills. However, good quality rim brakes work just fine, if you set them up right. You usually need a front fork designed for disk brakes, and of course the hubs have to be made to handle them as well. Several of the better quality Walmart donor bikes come with front disc brakes and the proper front fork, but I don't see any online in the 20" wheel size, that I believe the TradeWinds calls for.

[trikeman]

No idea why my reply got posted twice, so I trimed it to this.

[AtomicZombie]

Hello.

1) I used conduit, but you can use any round or square tubing that is close to the size specified. I don't remove the coating as it is very thin. A ventilator is always recommended for any welding, and yes, I also hold my breath and use a fan when welding conduit.

2) You are correct on all points there.

3) Yes, both rim sizes would be just fine - you can even drop the 700s on the MTB frame and adjust the brakes. I never use 700cc rims because I find they always bend. The roads are a bit rough here.

4) Being a steel only dude, I have no experience with alum, but would think the TM would be fine due to the diamond frame. You might want to add another truss though.

5) If you have the budget, disc brakes are the best. It is very easy to adapt any frame/fork to disc brakes.

Thanks!
Brad


(I originally posted the questions shown below here in the Ask Us section, and it was immediately moved to the Tourmaster section. But no one has responded so I'm trying it here again. Hopefully this will generate some discussion.)

Copied text:

I downloaded the TourMaster plans today and have a few questions I hope you can answer:

1. In the photos it looks like you are using galvanized conduit. Don't you need to remove the galvanic coating prior to welding? If so, what is the best removal method?

2. After studying the plans for a bit, it appears to me that you really only need one donor bike if you use a bit more conduit and some smaller diameter hardware store tubing for the seatback brace. I don't think the idler pulley needs a second BB--another method of attachment could be used for that. So that only leaves the second head tube for the handlebars. I think an alternative to scrapping an entire bike frame just for the head tube could be figured out. A narrower suspension rear end could be substituted, which would also eliminate the need to cut up the rear end. The seatback brace could then simply be bolted to the panier attachment holes. Am I missing something here? Is there some reason that makes chopping up two frames necessary?

3. Now for a more ignorant question: What is the difference between "standard" 26 inch wheels and 700c wheels? Might either be used?

4. I'd like to use a new/newish donor bike with decent hardware to build the TourMaster. But it seems that all the better new bikes have aluminum frames these days. Which brings me to welding aluminum. What's your recommendation in light of this trend? Have a professional TIG welder do the aluminum welding for me after I cut and jig the frame parts? Buy a scrap steel bike just for the frame and part out a new aluminum framed bike without using the aluminum frame?

5. Would it be worthwhile to upgrade to disc brakes for the TourMaster? For me the intended use is a 42-mile round trip daily commute in wet or dry weather, some low hills, and dark early mornings.

[guthrie]

About the steel. Could I drill holes in the steel to make it lighter without sacrificing strength? The holes would be evenly spaced, approximately 1" in diameter and span the long sections of square tubing on models like the Delta Wolf and Marauder. I have a marauder now, but it is very heavy especially with me on it.

[trikeman]

About the steel. Could I drill holes in the steel to make it lighter without sacrificing strength?

No. There is no way to drill holes in the steel without sacrificing some strength. That said, it may be possible to drill strategic holes that would leave the bike strong enough.

I am not sure how much the frame on your Marauder weighs, but given that it uses somewhere around 6'-8' of 1.5" square 16 ga steel at 1 pound per foot, it can't weigh more than 6 to 8 pounds, unless you are using thicker steel. I think the book says to use 3/32" steel, but most of us under 200 pounds are using 16ga (about 2/32). You might be able to shave maybe a pound by drilling holes, but it will definitely be weaker. How much does your marauder weigh now?

Assuming you drilled 1" holes in the sides, with an inch spacing between each one, you could drill 5 holes per foot. Since the tube is 1.5"x12" per foot it weighs 1 pound per 72 sq inches. A 1" round slug from the hole would then weigh (3.14159*.5^2)/72 = 0.0109 pounds per hole. So, if you drilled 10 of them per foot (5 on each side), you would save 0.109 pounds per foot, or about 10%.


If you were going to drill holes in the main beam (I wouldn't recommend it for the small weight savings), you would probably be best served to drill them in the sides, since most of the stress is born by the top and bottom of the tubes. That is the way an I-Beam works - it has only one center section and a wide top and bottom. The top and bottom handle most of the load. Since you are sitting in the middle of the main beam, with wheels at both ends, the bottom of the tube will usually be in tension, and the top will be in compression. Drilling holes in the sides will mostly make the beam more likely to flex from side to side as you peddle it and apply side forces to the cranks. This is never a good condition on a recumbent. I would also worry a bit about how you would protect the inside of the tubes from the elements with big holes in the sides.

Those calculations are for the Marauder. For the tourmaster or any of the other bikes, you can do your own similar calculations.

If you really want to build light weight bicycles, do as papa does and get yourself some Cromoly steel tube, a torch and some brazing sticks and learn how to use them.

[jimFPU]

Just knowing about basic metallurgy, drilling will change the molecular structure of the base steel, and could possibly make it weaker, due to the heat generated by the drilling...of course I'm no expert...

[TheKid]

And don't forget about moisture getting inside the tube. With all those holes the chance of rust increases dramatically, even if the inside is painted. You see holes drilled in aluminum to save weight, usually by weight fanatics, long range commuters, and racers who want to shave every ounce they can. There's a big difference between steel and aluminum getting wet.

[pcorbett]

Sorry. I overlooked this from Locutus post back in July. I'm looking into go fast tires too.

" QUOTE #3. Now for a more ignorant question: What is the difference between "standard" 26 inch wheels and 700c wheels? Might either be used?"

Far from ignorant, good question.

It's must be a moot point for Locutus by now but maybe someone else trying to choose a AZ bike could use this. I've ridden the Tourmaster for about a month and find it's the most comfy ride I have. That's just what this bike is. I think RB had said this. I use 2.125 X 26" tires fore and aft and gives it a cushy ride. It's weight is an issue to make it go fast so why bother with the go fast tires. This is a great cruiser and needs more phat than fast. I'll save the go fast parts for my Meridian and I would put them on my HighRoller first.

I came to the same conclusion about how many bikes it takes to make the Tourmaster. If I was to make another I choose the frugal route.

I'm not dissing this bike. It's my main squeeze. Now the Highroller is the one for the speed goodies, simple and fast.

IMMHO

Pete

[rickairmed]

Ok someone asked about drilling holes to lighten the Bike . Hot rodders have been doing it for years heres a link scroll down the page :D.


http://images.google.com/imgres?imgurl=http://www.classicstreetrodmfg.com/Images/Front%2520End%2520Comp/Drilled-Axle.jpg&imgrefurl=http://www.classicstreetrodmfg.com/front_comp.htm&usg=__Etppt6Cv8Voqc9ppkZ7EZ6q5AdY=&h=193&w=748&sz=22&hl=en&start=12&um=1&tbnid=EMr0-LczO79pvM:&tbnh=36&tbnw=141&prev=/images%3Fq%3Ddrilled%2Baxle%26um%3D1%26hl%3Den%26s a%3DN


Rick

[Doc Hollywood]

If I was to drill holes in a frame to lighten it up I would not only drill holes but use dimple dies to increase the integrity of the frame. Problem is you would have to build all four sides and then weld the edges. It would take a lot of work but the end product would be lighter and probably much stronger.

[rickairmed]

Doc very good point that is how they do actual frames on street rods .


Rick