Monday, May 2, 2011

Micro-Loading

This would seem to be the perfect DIY project candidate. There are numerous ways to micro-load. Today we're going to take a look at some of the popular options to see if it's really worth it. You can buy fractional plate sets for $50 online, plus shipping. This is going to be our price point. We not only have to get cheaper than $50, we have to get much cheaper. Otherwise, it's just not worth it. Can we do it? Let's find out.


If you buy plates online, for your money you get (2 of each) 1/4 lb., 1/2 lb., 3/4 lb., and 1 lb. plates.  We're not going to be able to make plates that function better than commercial ones because there is no room for improvement here. Our only hope is if we can make something that functions as well but is much much cheaper.

I'm assuming you work out from home. If you go to a commercial gym and plan to take your plates in your gym bag, I highly suggest you consider just buying them. Commercial fractional plates are clean, weigh the right amount, and are small and portable. Homemade solutions are typically not as good, at least in the size/appearance category.

WASHERS

The most attractive way is to use large industrial washers. No I don't mean washing machines, I mean the metal discs that one uses to fasten things in conjunction with a bolt or screw. You can buy such washers at stores like Fastenal. You can also order them online. These end up looking and functioning great, because they are essentially shaped just like little plates. At first thought they seem perfect, but the problem is, they get expensive quickly.

In order to make the same set as Iron Woody sells you have to buy two types of washers. There's a 2" flat washer for $3 that weighs just over 1/2 lb. And there is a 2" bushing that costs about $1.50 and weighs a bit more than 1/8 lb. With a bit of modification, combing two bushings gives you your 1/4 lb. plate. Two flat washers gives you your 1 lb. plate. 1 flat washer and 2 bushings gives you your 3/4 lb. plate. And of course 1 flat washer is your 1/2 lb. plate. When you total it all up,  you have to spend around $37 plus shipping.


This means all the work you're going to have to do to get these washers weighing exactly what you want them will be done in order to save you $13. That's not a great deal in my book. Especially since the commercial plates will look better and take no time or effort on your part. Now, there are certainly other places besides Fastenal to buy such things, but the story ends up the same, more or less. You don't end up saving all that much money.

However, before I throw this option out I must mention that if you can buy these washers in a local store (no shipping cost) AND you only want a few increments (not the full set) then it may be worth it to simply buy a few 2" washers and use them to microload 1 lb. on to the bar. But if you want the 1/4, 1/2, 3/4, 1 lb. set these washers just become too expensive in my view. Not to mention that if you want your washers the perfect weight you'll have to be able to weigh small increments at home. Since they don't naturally weigh 1/4 and 1/2 lbs. you'll have to trim off (drill holes) to lighten them.

There are other options though. None of them will look as nice as commercial plates or washers. But if you are training from home (not taking them to the gym in a bag) and don't care how they look, you can get the same effect (adding weight to the bar) for much less money.

CHAINS

The second most popular idea with micro-loading is using metal chain. Doing this will require that you have the ability to weigh small amounts (like a kitchen scale). If you lack this ability you'll have to buy a kitchen scale. This then brings up the idea of how accurate this scale is. If you buy an inexpensive one powered by a spring one has to wonder if it's even accurate. If you buy an expensive one you've just destroyed your budget. Saving money is the only reason to make your own fractional plates.

The concept with metal chain is to measure out a length of chain that weighs what you want it, be that 1/4, 1/2, 3/4, or 1 lb. If the chain is a small link you may be able to make it long enough to completely wrap around the bar. If not, you'll have to complete the loop with string so that you can hang it on the bar. You'll also have to put some kind of tag on it to mark what weight it is. This will no doubt be much cheaper than $50. But it doesn't look as good. You'll have to be able to cut links off the chain. A pile of chain is not as neat as a stack of plates. You have to be able to precisely weigh small amounts.


ENDLESS COLLARS

A third popular idea is to stack collars onto the bar. I'm not a big fan of this idea. Sure, in a pinch it would work but stacking many collars onto your barbell isn't practical.

If you go to a commercial gym, where you have an abundance of free collars to use then I won't criticize. But if you lift from home, obtaining that many collars would not be cost effective, nor is it neat and easy to load up the right amount.



CREATIVE RECYCLING

Since I've done it in the past, I figured I should mention this. The picture to the right shows "screw on" collars which some cheaper standard 1 inch bars use. I had some from my old adjustable dumbbells. I used the dumbbell bars to make my dip station handles. These collars weigh roughly 1/2 lb. each. By looping some twine through them you can make weights that slip over your bar. By putting two collars on one rope you make a 1 lb. weight. I had enough collars to make two 1/2 pounders, and two 1 pounders.

I never use these.  I prefer the wooden plates (see below). But these are very compact. If you already have such collars lying around you could convert them to micro-weights that would easily fit in your gym bag (if you go to a commercial gym).

THE PLYWOOD METHOD

You can also make fractional plates out of wood. They won't be nearly as durable as metal, but how often do you use fractional plates? I think you can discipline yourself to treat them gently enough to not break them. We're talking about wood here, not glass. As long as you're not an idiot you should never have durability issues. You'll still need the ability to weigh small amounts to do this project. You'll also need the tools to accurately cut wood, particularly the center hole. This basically means a hand saw (or power saw of your choice) and hole saw. The concept is exactly the same as the Spacer Plates project. The difference is you'll be cutting a smaller plate out of the plywood.

This is my favorite option. It produces a quality plate that looks pretty nice. It's easy to mark the weight on it. It's durable enough as long as you treat it properly. It won't be as small and neat as commercial plates or washers. I certainly wouldn't load them up into a gym back to take with me. But if you train from home, you can make them for dirt cheap. If you have scrap materials you could even make it for free, like I did. It will, however, take the longest out of all the options. You're looking at about half a day when you add in the calculations, measuring, cutting, and painting. If saving time is your goal I think the chain is probably the middle ground between making something and buying commercial plates. Now, I'm going to show you how to make your own set of fractional wooden plates.

Not the prettiest girl at the party (and also not the ugliest), but she gets the job done and is easy to use.
You certainly don't have to use "plywood". Any thin wood material, such as MDF (medium density fiberboard) will also work. I chose plywood because there always seems to be scrap leftover in my garage, thus making the entire project completely free.

The key to this project is math. You can't simply weigh a chunk of plywood and then trim it down until it's 1/4 lb. Well you can but that's the most unsophisticated, sloppy, and time consuming thing I've ever heard of in the history of homemade fractional plates. Let's do it the proper way instead. First we need to know how much our plywood material weighs per square inch. If we know this, then we know exactly how many square inches of material we need to make each plate.

The simple way to determine this is to cut out a 1" by 1" square of plywood and weigh it. This of course requires that you have a scale that can accurately weigh small amounts. If you don't have a small scale that can weigh small amounts then making your own micro-loading plates becomes much harder. You have to find an option where the manufacturer tells you how much the item weighs (such as with the washers) and then you just have to trust them. I have said scale in my kitchen which I bought strictly for culinary reasons, to weigh cuts of meat when I get fussy enough to actually count my calories when bulking.

Once you determine how much 1 square inch of your plywood weighs, we can move on. For what it's worth, I'm using standard 3/8 inch plywood from any major hardware store, like Home Depot or Lowe's and it seems to weigh about 0.011078 lbs.  per square inch by my measurements. Yes that's a small number but it adds up quickly. Remember we're trying to make plates that weigh as light as 0.25 lbs. Having this information is vital in determining how much surface area our plates need to be to make weight. Like I said, you'll want to measure this yourself at home. If you simply take my figures, you are trusting to my math (not the worst idea) but you're also trusting that your wood is exactly the same as mine. I certainly don't guarantee anything. All I can do is tell you what I did and what it produced, as told to me by my scale.

Disclaimer out of the way, you've got two options when shaping your plates, circle or square. Square is easier to cut, no doubt, but circular looks more like a weight plate. Circular plates also have to be bigger than their square counterparts of the same weight due to the nature of the shape missing corners. It's also slightly more complex determining the surface area of a circle than a square. A square is simply length times width. But since you have to cut out a circle hole in the center to fit on the bar we have to learn and run these calculations anyway.

The equation for calculating the area of a circle is Pi times the radius squared. Pi being 3.14 for our purposes. The radius being half the diameter. This is high school math but if you don't remember it, don't worry I'll walk you through it.

As I said, the material I'm using weighs roughly 0.011078 lbs. per square inch. So if I want a piece of this plywood to weigh 1/4 lb. (0.25) How many square inches does it have to be? To figure this out we take the desired weight (0.25) and divide it by the weight per square inch. So 0.25 / 0.011078 =  22.567 square inches of material needed.

Regardless of whether you choose to make square plates or round plates, before we can determine the outer size of the shape we need to cut, we have to take into account that there will be a hole in the center of this plate. I recommend that you use a hole saw to cut this. I used a 2 1/8"  hole saw designed for cutting the hole for a doorknob. Using the area of a circle equation (3.14 x radius squared) we can deduce that such a hole has an area of 3.545 inches. We have to add this to our desired surface area of 22.567. This gives us a total area of 26.112. We need to measure and cut a plate with this surface area, so that when we drill out the center hole it will then be 22.567 square inches, which weighs 1/4 lb.

SQUARE PLATES

Though they don't look as official as round plates they are far easier to calculate, mark, and cut. It is for this reason that I chose to make square plates. All you have to do is calculate the square root of your desired area (26.112 in my case). This would be 5.11 inches. This means if you cut a peice of wood that is 5.11 inches by 5.11inches (a square) you'll end up with something that weighs 1/4 lb. after you cut the 2 1/8 inch hole out of the center.

For the heavier plates you take your base area measurement (22.567). Since we know this amount weighs 1/4 lb. we multiply it by 2 for 1/2 lb., 3 for 3/4 lb., and 4 for 1 lb. You then add 3.545 to this figure (to account for the center hole), and take the square root of that. So for a 1/2 lb. plate it would be 22.567 x 2 =  45.134. Then 45.134 + 3.545 = 48.679. The square root of that is 6.977. Round that to the nearest sixteenth of an inch and you get a measurement of 7 inches. This is both the outer width and length of your square for your 1/2 lb. plate.

Repeat the procedure for the rest of the plates. For me the 1/4 lb. plate has sides of 5 and 1/8 inches. A 1/2 lb. plate has sides of 7 inches. A 3/4 lb. plate has sides of 8 and 7/16 inches. And a 1 lb. plate has sides of 9 and 11/16 inches. It's worth noting that even the largest 1 lb. plate, measured on a diagonal from corner to corner, is a bit less than inches long. This is smaller than the diameter of a standard iron 45 lb. plate. So if you did need to micro-load a pull from the floor, for some reason, the fact that there are square will not interfere.

Now the easy part. All you have to do is measure your squares on your plywood, mark it, and cut it. Use any saw that you please. To ensure precision and no chipping I used a simple wood hand saw. A hole saw is the best way to cut out the perfect center hole.

CIRCLES, HARDER AND PRETTIER

There is no functional reason for your plates to be circular. But if you just have to have circles then you have a bit more calculations to do.  You have to plug your desired area into the Pi x R squared equation. We've already calculated that 22.567 square inches of the material I'm using weighs 1/4 lb. This is number we start with.

The area of a circle = Pi x R squared. So 22.567 = 3.14 x R squared. Now we need to isolate the unknown variable. In this case it's the radius "R". Isolate means to get it on one side of the equal sign "=" all by itself.  So the first thing we're going to do is divide by 3.14.  Whatever you do to one side of the equal sign you have to do to the other. So 22.567 divided by 3.14 is 7.187. "3.14 x R squared" divided by 3.14 is "R squared". Now our equation looks like this "7.2338 = R squared".

To cancel out the "squared" part of the equation we use the square root function on our calculators. Now we see that "R = the square root of 7.187" or" R = 2.681". That gives us the radius of the circle we need to cut. Multiply it by two to get the diameter. 5.362 inches is effectively the size of the circle we need to cut in this plywood to make a plate that weighs 1/4 lb.

To calculate the size needed for 1/2, 3/4, and 1 lb. plates we repeat the procedure. Starting with our figure of 22.567 square inches (which weighs 1/4 lb). We simple multiply it by two for 1/2 lb, by 3 for 3/4 lb, and by 4 for 1 lb. For each plate we then add 3.545 to the figures we get (to account for the hole we're going to put in the center). Then we repeat the Pi x R squared calculations in the above paragraph.

Using these calculations I find out that, rounded to the nearest sixteenth of an inch, to make a round 1/4 lb. plate I need to cut a circle with the diameter of 5 and 6/16 inches. And as shown above I could figure out what size circle I need for each of the other weights. Of course I won't be making these because I chose to take the easy route and made square plates instead.

Now the challenge is to draw your perfect circle and then cut it out as perfect as possible.  If you don't have a compass or circle tracing tool this becomes much harder. Tying a string to a pencil is a technique that would work if you aren't trying to be dead on balls accurate, which we ideally are. We know we'll be off somewhere during the process but we want to do our best to minimize it. It is this reason why I just pussed out and decided to make square plates for myself. Easy to mark, and easier to cut; because it's all just straight lines. If you want circles, you'll have to find a way to mark them as perfect as possible.

After you mark them, use whatever saw you choose to cut them out. It will either need to be a jigsaw, a Rotozip style saw, or a coping saw. If you use a coping saw you'll have to rough out the shape with a normal hand saw first. Just like we did in our Spacer Plate project. Using a hole saw is the best and easiest way to cut the center hole perfectly.


FINISHING TOUCHES

If you do have a scale sensitive enough to weigh your new plates, do so now to ensure they are close enough to your liking.  If they are significantly off, then something within the system has malfunctioned. Hopefully they are too heavy so that you can remedy it by sanding down the edges.

Now we need to mark them so we know how much they weigh. You could simply use a marker, pen, or paintbrush to write the weight on them. That's certainly the fastest. If you want it to look fancy, print out the weights from your computer. Use an X-acto Knife to cut out the numbers. Now you have a stencil that you can give a quick spray paint over your plates. If you have it, using a glue stick on the back of your stencil will ensure that it stays stuck to the wood and completely flat. The paint won't get anywhere it shouldn't if you do this. If you don't do this, the stencil is likely going to be blurry. I did not use a glue stick in this project because I didn't have one and you can see that  my marks are indeed blurry as a result. I have done stencil work on guitars that I've made using the glue stick technique and it comes out very nicely. But as long as you can make out the lbs. who really cares, right?

If you want to take it one step further. Give your plates a single light coat of lacquer or other clear based finished. As long as you don't go crazy the paint / lacquer shouldn't add any significant weight to the plates.


As I said, if you wait until you have scraps to use for this project it can end up being free. Yes, it does take time, longer than any other micro-loading options, but it's by far the cheapest. If you're bored and have the scrap materials to make this for free, and a scale to make sure you're weights are right, then it can be a fun project. But I like math so my definition of it being fun may not apply to you. If you simply can't be arsed to do any of this then buying your fractional plates is not a bad choice. All cheaper DIY options will require you to have the ability to weigh your finished product.

- Carl

4 comments:

  1. For (almost) perfectly circular discs a belt sander is a great tool for finishing. After taking of the bulk of the scrap with a jigsaw put a nail through the centre point of the disk into a straight edged block so that the edge of the block lines up perfectly with your desired radius. Then push the disk up against the belt sander until it touches the block and slowly rotate. Of course you will want to use a hole saw afterwards for the hole.

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  2. Thanks for the Fastenal washer idea! I picked up 2 today. Much cheaper than fractional plates which are a rip off.

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  3. Or...you can just purchase the Bat Weights that batters use to warm up on. They are almost at all sporting goods stores that sell bats and batting supplies. They easily fit onto olympic bars. And you can buy 16 oz = 1 lb or 20 oz = 1.25 lbs bat weights. all typically under 10 each. just search online for keywords : bat weights or batting weights

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  4. I bought four floor flanges at Home Depot's plumbing Department. It is solid steel. Got the one for a one inch pipe and it fits on my handles nicely. 9.56 ounces each.

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