This is a project that you can do on the cheap with minimal parts (some to most of which you may already have). I had been trying to think of ways to build some rollerskis ever since the dismal ski season left me wanting. You will need either ski or hiking poles to make this project work, and since this should only be attempted on concrete, as these are essentially elongated inline skates, ski poles or hiking poles with shock absorption must be used to help propel and balance you.
Before I get started, let me be clear: ski-skating is the dry-land adaption of the nordic skiing styles, and is how cross-country skiers train in the warm months. There are two techniques that will define how you build and ride your ski-skates, which I will discuss later on.
Here is the reason you should make these: it is insanely good exercise. Depending on the style of ski-skating you use will depend on what you work the most. You can use the classic cross-country style or the normal nordic style which a longer skate is better for. You can also choose the skating cross-country style, which is what I've choosen. I will say you will have to choose which you want and then build around that. Do not think you can make one ski for both. Also, the reason you are building instead of buying them is they are very easy to build as long as you have access to a drill and saw, and even the most entry-level person could build a working pair. A professionally made pair will run you around 300 dollars with bindings for real ski boots. I opted to take old soccer cleats, remove the front studs, and permanently tack them down, allowing the heel to move free as is necessary for this technique.
Watch this if you want to learn about and develop rollerskis for the Classic technique
Watch this if you are more interested in the skate-style of cross country.
I suggest before you do this you do a little research into it so you understand everything required of you physically and in the construction before you invest in it. It is easy to build, but not necessarily easy to master.
Also you cannot do anything more than EXCERSIZE in the model I provide or anything similar, don't think you can either offroad, go on rough terrain or try doing stunts or other dangerous things in these, as they will simply not hold up. Always wear head protection even after you have adapted to this, and I suggest knee, elbow, and possibly wrist and hand protection as well. Especially if you don't live in a flat area like Indiana...
Step 1: Choose a Style
Which way you gonna burn them calories? Classic or skate?
If you watched the Olympics religiously this winter like I did, you may have seen the Nordic relays and races. Basically, the classic skiers operated in pre-made straight tracks that ran along the entire course, while skate skiers skated on groomed flat surfaces in their sweeping v-motion (similar to an inline rollerblade).
You will need to mount your shoe in the very middle to add stability. These do not need to be very long, so the length of the chasis shouldnt exceed 2 feet. I'm a big fella so I maxed out at 2 feet, a bit longer than a normal skate. This gives me the weight in the skate itself I need to make my boot flex and allow me to push through the stride.
If you choose the classic technique, look to the photos of models that have shoes mounted near the back. This style operates in a straight line, so long skis that spread you out and makes the skis strides longer are best; definitely over 2 feet, but not anything more than 3. The reason this style works with the foot mounted to far back is you will always have a foot flat down and rolling solidly forward, so it's less of an issue than if you were using the skating method.
The next step I will get to how to assemble these babies.
Step 2: Assembly 1
First, choose 2 or 4 wheels. Note that if you are heavier, you will be doing 4 wheels or breaking your rollerskis and possibly more. Best go big. It also means you don't have to use as thick or a shaped frame to attach it all, because the wheels and screws give it more strength. simple formula; 2 wheels= square frame that costs more, 4 wheels= 2 bar frame with middle block. Cheaper and easier to construct and repair.
I bought 1"x4' aluminum bar for this. Any major hardware store will have it. In shopping for a particular thickness, it is best to find one that is both strong and still light; I did it by finding one that I couldn't easily flex out of shape. If you don't feel confident, go up the added .0008888mm. Confidence is key. :)
You will also need 8mm bolts, a lot of washers (near about 50) and nuts. Scrap wood is good, but for the footboard I wanted the good stuff, so I bought some project oak, which is of a dimension I no longer recall. Lets just say this: you are putting your body weight on it in part. doesn't need to be too thick, but it can't be as thing or as flimsy as balsa wood. It is easy to attach the footboard to the middle block, tho... 2 wood screws is all you need (however, don't use ones with an odd-shaped screw head. I used a square shaped one, just to be difficult, and they kept stripping out and leaving metal in my boots and the wood. No. Phillips head is the best.).
Also if you build it like mine, I had a 1"x1"x8' (it may have been 1.5 x 1.5 I may be lying) piece as scrap that I found. You connect the footboard to that and it is the median between it and the skate rails. Simple design is best...
As for the actually build, I suggest for skaters one wheel at each end and then one right near the block you mount your shoe on, to make sure there's not too much bending. That will give you a decent distribution of weight.
Step 3: Getting Them Ready
Once you have all your holes drilled, pieces fitted, etc, you need to adjust a few things.
The wheels are attached to each side of the frame with 3 washers on each side of the wheel, if you are like me and using skate wheels. Mine came with bearings, and I got 8 for a modest 20 bucks. Now, the wheels has to be tightened up just right; too loose and the wheels will be REALLY fast, and, this is not a speed sport first, this is a resistance and aerobic sport. You want to keep a constant speed and not build speed; hence, you tighten the side bolts which squeezes the washers against the bearing in the middle of the wheel, which, makes that bearing slower. You may not have to do that on all the wheels, but on some I suggest it. Also, be aware of how skate wheels are rated. Yes, not all are the same. I couldn't find soft wheels, wheels that are labeled with a 78 softness rating, and instead got what is considered a hard 82 for skate wheels. Look for this on the packaging. I would have gone with 78's if I could fine them, but oh well...
Now that's wheels. The boots have needs, too. Refer to the below picture of the boot sole and the different bindings... notice the straight groves. Cross country skiing requires the boots to be latched in the toe which allows the rest of the shoe to flex as you move. However, you only want to flex in one direction, up and down, and NOT side to side. In tacking your boots down, make DOUBLY SURE that it is only able to move up and down. If it can move side to side, you have more work to do. However, make sure that you don't put a pincushion in your shoes...
Step 4: Classic Skiers?
Well, I have neglected you.
Okay, if you are interested in this style, as for construction the only difference is instead of constructing it like this: wheel wheel middle block wheel wheel, construct it like this: wheel middle block wheel wheel. A tire at both ends and then one on the opposite side of the middle block. That should make everything sturdy and keep things light; that is what it is all about.
Otherwise, no further modifications are neccesary. You could consider using flat wheels instead of round inline wheels, and I have seen them at the store recently. The classic technique is, literally, pretty straight-forward; you won't need the rounded wheels for turning. Flat ones just make things more stable and make more sense.
Step 5: All Done!
First off, that was my first instructable. : )
2nd, my stupid knee is hurt and I just finished making these, so I can't really tell you how well they work. I will brave the pain tomorrow and try them out rain or shine, with copious amounts of padding. Because that is just how I doo....
*EDIT: I got all geared up and then, come to find, the first flaw in my design. Soccer cleats focus a lot of your energy into the center of the boot, and this does not bode well when adapting them to skates. So I will remove those and put some normal flat-soled shoes on, and then update you all.*
Really, it's not rocket science at all; these are no different than ones you would pay 200-300 dollars more for, albeit the different parts used. They may require some tuning, yes, but ultimately I think they are nifty.
Thanks for reading! If you got this far!