[Amberwolf]

Originally Posted by KrisWood

Thanks for the feedback Amberwolf! I guess I'll go with the intermediate jackshaft after all. Now if only I had a lathe I could reduce the axle width of the motor to something a bicycle cog would fit on.

Well, the drill press can be used as a lathe if it has really good bearings, but they are not usually meant to take sideloading. So rigging up a centered bottom "table chuck" to clamp the other end of whatever you're going to work with in is a good idea. Making a tool holder is troublesome, but a vice can be used.

Googling has turned up that the kind of stub axle I need can be found on gokarts and wheelchairs. They are most easily obtained from gokart hobby shops. One person also suggested 14mm BMX hubs as they won't require any modification like a standard 10mm bicycle hub would.

I am using wheelchair ones on my trailer, from a Quickie brand chair; but they are quick-release so you'd need to lock up the wheels to the bike if you leave it.
Remember that wheelchairs are not meant for fast bumpy road use, so the axles of most may bend easily under such stress. Normally the fastest they see is walking speed, and on bumpy areas much much slower than that. AussieJester on ES bent many axles on chairs just hand-wheeling them around with just him in it until he got his Quickie, which has titanium axles.

By posting on other trike fora I've also learned of another serious flaw in my design; I cannot use wood for the knuckle that holds the axle. It's apparently not strong enough to hold up against the vibrations on the road. I think I'll try it anyway though.

For the knuckle to hold the axle, you might try copying what this guy did:

http://www.endless-sphere.com/forums...=14474&start=0
http://www.endless-sphere.com/forums...218969#p218969
Basically just takes the entire seattube including bottom bracket and cranks off a bike, removes the crank with the chainrings on it and replaces it with a blank one at 180degrees so it now lines up with the other side. Cut both to length to bolt thru them to whatever you attach the wheel with (block of aluminum drilled thru would work, instead of the welded stuff he used). Kingpin steering link would be something bolted to the block or the former cranks, sticking back to a pivot point.

If you need more structure to bolt to, leave both the down tube and the seattube attached. Or even leave the top tube and headtube, so you have the whole front triangle. Line up the top tubes from each bike so they are parallel to each other, with seat tube top ends cut to match. Bolt thru both top tubes to clamp them together, then build your wood frame around that.

If you are not gong to angle the steering joints, but instead keep them vertical (not as nice a steering performance but fine for very low speeds), then keep the head tube and seat tubes in line with each other, and bend a seat post so it can be inserted into both seat tubes half way. Then clamp that down into the seat tubes, and do something similar to the head tubes, and you now have a stronger frame without welding.

[KrisWood]

I just had an alternate idea that should work! Check out how the rear dropouts were made here:

http://blog.borisbeaulant.com/2009/05/trois-sur-trois/

By sandwiching sheets of metal between sheets of wood he was able to get both the strength of metal and the aesthetics of wood. I think the same could be done here. Failing that I could cut out sheets of metal to make each face of the knuckle, then bolt them together with L brackets. It'd be fiddly but should be strong enough for testing purposes.

Now I just need a jigsaw strong enough to cut metal.

[Amberwolf]

Use a hacksaw with a 24tpi non-offset blade and you can cut bike tubing and pipe easily enough, and most sheet metal up to 1/8" thick.

A jigsaw works ok on aluminum (when it doesn't gum up) but sucks on steel, as it usually just rips up the edges if it's thin and wears out the blade too fast if it's thick.

If you can borrow a circular saw with at least a 7" blade, you can buy reinforced abrasive metal-cutting blades and those make short work of most thicknesses of steel or aluminum. Just set the blade depth for the metal thickness plus a hair, and cut it while clamped down on a scrap board. I use old particle board shelves that people discarded because of dampness or wetness that distorted them; usually enough of it is flat so I can cut off the worst parts and be left with a good stiff clamping surface that can be abused with shallow cuts until it falls apart.

[KrisWood]

Ooooh good idea on the particle board! I've got tons of old seemingly useless particle board in the garage and basement. I've also got plywood in similar quantities.

I was ecstatic to discover today that the drill press I got off craigslist today is the same brand as the drill press clamp I use for my jewelry projects. The bolt holes line up perfectly between the two.

I'm going to buy the jigsaw, some aluminum sheet, bolts, and maybe some wood tomorrow. It'll be interesting figuring out how to carry it on the bike, but a friend of mine found me a trailer for $20 that I'll be picking up too, so maybe I can get that first.

I do have one more question though on the jigsaws. There are three levels of quality to these things; $15 to $30 for cheap ones that'll do fine with wood as long as I don't need detail or heavy duty work, $30 to $70 for budget ones that will do everything I need including cutting aluminum but are still not terribly reliable, and $100 to $150 for the high end ones that do it all.

I'm considering the best of the low end ones at $70, though it's got abysmal reviews, because what it lacks in precision it makes up for in the ability to do heavy duty work. It's not very important to me to have this prototype look good. However if I'm already spending $70 on a low quality machine I may as well spend $100 on the lowest of the high end ones. The trouble then is, if I'm already going overbudget for a high end one, I may as well put out the $150 for the best of them.

I know very little about power tools, so my question is, is it worth spending extra on a tool that'll last and do an excellent job, or is it better to get something inexpensive that matches my relatively low skill level that can be discarded and / or replaced when money is easier to come by and / or the cheap tool breaks down? Ugh, I'm torn...

In computers it's easy: Always buy name brand for any mission critical components, never skimp or you'll have an expensive paperweight within six months. Never buy the top of the name brand either, because in 3 to 4 months it'll be obsolete. Cars are similar, there are some parts you just don't get the cheapest part on because you'll just be replacing it soon if you do. Do these rules of thumb hold true for power tools too?

[Amberwolf]

Originally Posted by KrisWood

I was ecstatic to discover today that the drill press I got off craigslist today is the same brand as the drill press clamp I use for my jewelry projects. The bolt holes line up perfectly between the two.

Sometimes synchronicitous technology appears. This happens fairly frequently to me, in puzzling circumstances--there is a post on my blog by that name for that reason, with an interesting coincidence.

I'm going to buy the jigsaw, some aluminum sheet, bolts, and maybe some wood tomorrow.

If you are getting the aluminum to sandwich with wood to make structural parts...don't. Get steel, if it's for those knuckles and stuff. Harder to work perhaps but will not stress fracture as it flexes, which is what will happen to the aluminum sheet. Once it fractures and cracks it will no longer be reinforcement within the wood.

I do have one more question though on the jigsaws. There are three levels of quality to these things; $15 to $30 for cheap ones that'll do fine with wood as long as I don't need detail or heavy duty work, $30 to $70 for budget ones that will do everything I need including cutting aluminum but are still not terribly reliable, and $100 to $150 for the high end ones that do it all.

The only jigsaw I have is a decades-old mustard-colored Black&Decker basic model. It's only big flaw is the set screw to hold the blade in, which vibrates loose every few minutes in wood, and every few seconds in metal. Since it was used when I got it, I don't know if that was always a problem with it. I think it was less than $5 at a yard sale, ages and ages ago. I'm sure I could fix the set screw problem if it ever bugged me that much, but I rarely need it on the same blade for longer than the set screw holds, anyway.

Really, the blades probably matter more than the jigsaw itself. Never use cheap blades--either they will just wear quickly or worse they'll break in use and either go flying in bits and pieces, or damage the material you were working on.

I'm considering the best of the low end ones at $70, though it's got abysmal reviews, because what it lacks in precision it makes up for in the ability to do heavy duty work. It's not very important to me to have this prototype look good. However if I'm already spending $70 on a low quality machine I may as well spend $100 on the lowest of the high end ones. The trouble then is, if I'm already going overbudget for a high end one, I may as well put out the $150 for the best of them.

Find the ones that are made the best for the price. Trust the reviews by people that actually know how to use their tools (this may not be determinable, but sometimes they give away their lack of understanding in their complaints, and while that doesn't make their complaint less valid, it could be that the problems they had were caused by not knowing how to use the tool. It's a common issue).

Check out the demo versions of the tools on the shelf. Look for broken stuff. If it's broken just sitting there being looked at and handled, it won't hold up during actual use, either. :P Make sure the place has a 100% return policy within a time frame that you think will let you determine viability of the tool for your purpose, and doesn't preclude returning it in used or even broken condition if that's what causes you to return it.

If you see a tool with a lot of functions that is the same price as a tool with only one, probably (but not always) the single-function tool will be better-made, or at the very least better-designed for it's primary use.


Those rules of thumb probably apply to anything at all. Name brand only matters if you know that brand is not "made in china", meaning cheaply made (regardless of actual source of product). Lots of name brands have crappy stuff. But some have better warranties or return policies than others. For instance, typically you'll have better luck getting something returned or fixed at Sears than Harbor Freight. The tools might not be any better quality for the price, though.

What I have tried to do when possible is find tools for sale on CL and stuff, look them up online and see if that model/brand was a good one, and then see if it's sold yet. If the price feels high, offer less, and sometimes they'll bargain and you'll get a really nice tool for a much-less-than-retail price. Just make sure you can see it in operation before you actually pay, since there are no warranties with such purchases, usually.

Usually I can't afford what I do find regardless of how great a deal it is, but sometimes there are some killer deals out there from people giving up a hobby for whatever reason (economy, got married and wife doesn't want to deal with the hobby, moving and doesn't have space, etc).

More typically I find my best deals at thrift stores or at yard sales. Many thrift stores have no idea what they've got, especially with more unusual tools. I got a 3-jaw puller once for 50 cents that was probably at least a 30 dollar tool, and looked unused. I got a rusty but functional lathe off freecycle for just the cost of lunch for the person helping me haul it in their truch. A nice drill for nothing that a friend found in the trash at a church, along with a bunch of other stuff probably dumped by someone cleaning out storage sheds.

Reminds me...check storage facilities around you that rent out sheds and spaces, because lots of people fill up spaces with all their tools and stuff, then don't pay rent on the space, and the facility may throw out all the stuff or sell it cheap to get back some of the rent. I think there's a guy here on DIYEC that cleans out sheds like that for someone and sells the stuff, so maybe he'd be a possible contact. It's mentioned in a thread discussing container homes or something like that, if you can find it.

[toddshotrods]

Amberwolf gave a lot of great advice, I'll just add some points on the jigsaw.

If you're going to be cutting various materials, variable speed might be your best friend. I had a variable speed, cheaper-end, Skill jigsaw that I thouroughly abused for years and years cutting everything from wood, to steel (from 20ga to 11ga), and aluminum (from sheet to 1/2" thick). It couldn't cut straight to save my life, but it cut an unbelievable amount of material over those years. By "couldn't cut straight" I mean the blade would always end up cutting on an angle (vertically). I compensated for this by learning what direction the blade was going to drift to, and making sure I was on the oustide of the line for the total thickness of the material - then clean it up with sanders and grinders later.

The variable speed function was the key. The trick to not gumming up the blade in aluminum is slowing it down, and using a bigger toothed (lower tooth count numerically) metal blade. You want to see it throwing relatively big chips, instead of fine powder. You'll make it through the material before you start melting it. If it starts getting hot, gummy, or grabbing the blade, just stop and let it (air) cool for a while.

I was able to rip through steel without issues. The thinnner the metal in steel, the higher you want the tooth count. I used my jig saw on sheetmetal a lot. Enough teeth, and the right speed, it willl cut like butter.

My old skill jigsaw also had an orbital blade motion feature that I used on aluminum as much as wood. It allowed the blade to dig in for the cut but kind of pull away when recycling. I think this let the blade run cooler and more effectively. I thought it would kill the saw, as it was a cheapo brand/model, but it lived a long life. I bought another cheap Skil to replace it (same features), but haven't been doing as much hand fabrication work since. I have some professional grade tools, but buy the cheap, disposable, models sometimes when I am planning to do things with them that aren't really recommended...

[KrisWood]

Well, no luck on jigsaws but I found a lathe on freecycle, waiting to hear back if he still has it or not. I also found the original model of Shopsmith on craigslist for $100, but it's missing the parts to function as anything other than a drill press, probably restorable though. I asked him if he'd be willing to come down on price.

http://portland.craigslist.org/mlt/tls/1787427225.html

I'll keep my eyes out. Meanwhile I'm still pondering on the new jigsaws. I've asked around and it really comes down to how often I'll be using it. The answer there depends on how successful my trike is, because if it works well I think I'll be building more of them.

[TX_Dj]

I'd think using the drill press as a lathe will work fine, so long as you set it up right and really don't try to take too much off in each pass. The trick becomes how to rig up the cutting tool.

But, the REAL problem is the 3:1 rule, no more than 3x in length vs 1x the diameter of the stock sticking out of the spindle (drill chuck in this case) without using a center on the tailstock to support the material. This would limit you to 1.5" parts with a 1/2" chuck on the drill press.

There are some really cheap small lathes that may be right for your purpose, but finding them used can be a bit iffy.

Don't know about your neck of the woods, but the Harbor Freight shop near me is selling their 7x10 mini lathes for $399 on sale right now. It does seem a bit costly for an initial purchase (especially since you'll also buy that much in tooling and setup/precision measuring equipment) but in the long run once you have a lathe you'll find all sorts of things you need it for.

On craigslist, sometimes you find used lathes for quite cheap, including tooling.

[KrisWood]

I'm off to Home Depot to get the jigsaw and remaining building materials. I'll start off with either a 2x2 or a 2" diameter pole. The latter will allow me to follow the instructions more precisely and the former will be more easy to fasten together.

I will probably need thicker boards for the second prototype but for now this will allow me to follow the instructions for the Thunderbolt and make adjustments in the next model.

I hope to build the main frame today, then start planning the chain and seat stays and the steering knuckles.

[KrisWood]

Well, I made a field trip to Home Depot today and discovered a few interesting things.

First, they don't sell sheet metal in thicknesses greater than about 20ga, definitely not something I can use for structural parts. I'll have to find a different source for that.

Second, they don't sell hardwoods in 2x lumber! The closest I could find was some 1.5" diameter hemlock pole that was apparently intended for banisters. It's definitely more sturdy than the 2x2 pine and ceder was. That stuff bent just by holding it, the hemlock poles are so hard I don't think I could bend them if I wanted to.

I also bought the Bosch 1590EVSK jigsaw for when I finally do find a place that sells the sheet metal, as well as some bits for my drill press.

Now, speaking of the drill press I have a question. How does one use a hole saw on round wood that's the exact same diameter as the saw itself? With a drill bit I'd clamp down the part to be drilled in my drill press clamp and drill right down. With the hole saw though I'm going to end up cutting my clamp (and probably breaking the saw). If I shift the clamp over so that the part I'm sawing is under the saw but the clamp is not, it's gonna vibrate all over the place, I think. Do I need two clamps? If so, I don't see how I'd possibly bolt them to the drill press. *sigh*

The part I'm trying to figure this out for is the cross members. I'm going for the 90 degree ones for simplicity's sake.

http://www.ihpva.org/Projects/Practi...ons/fab_2.html

Specifically this step:



The only difference is that 2" stock in wood is a bit smaller than 2" (1.5" diameter in this case so I'm using a 1.5" hole saw instead of 2") but the end result will be about the same.

The only solution I can think of using the tools I have, is to have the clamp off to the side a bit so that it is only halfway under the hole saw. This way the 1.5" diameter of the saw will be just outside the clamp while the rest of it will be within the area secured by the clamp. Hmmm...

I'll be making another field trip to a sheet metal place to get the rest of my materials I guess. I'm also considering recruiting a friend with a truck to help me retrieve one of the many free dead pianos off Craigslist to use for building materials, since they are almost always fruit woods.

Also while waiting for a train on my journey, I noticed something that will make the drivetrain much simpler! The crank gears are riveted or screwed together, four per gear in a + pattern. I bet I could get a bit for my drill press that can thread four bolt holes into the flywheel of my motor, then screw some crank gears to it. Then there's no lathing required. All that's left after that is a jackshaft or left-mounted sprockets on the rear wheel.

I'll have some photos to upload tomorrow once I've got stuff cut out!

Edit: ok I lied, my friend just sent me a photo of the wood and jigsaw on my cargo rack, so I have one to upload today! Here you can see the beginnings of what will be my frame!