My DIY e-drum: off-set style symmetrical “middle” pedal

Here we are with a third post in the DIY e-drum series. This time we’ll be talking about something that may sound strange — or at least a bit off. An image is worth a thousand words.

Say hello to my 300 €, DIY version of Off-Set double pedal.

OK, if you are not a rookie in drums world you probably have seen stuff like this before.

Why then I decided to build one by myself? I’ll do a little step backward.

Find your center

Courtesy of myself — Source: my site :D

Since early 2000s I play a double bass kit, setup like in the picture.

It may or may not be visible by that schema but it is heavily symmetrical. Beside the hi-hat on the left (12, but another remote is on the right, see #9) and a floor tom (E), the rest of the kit is as symmetrical as it can get.

I’d like to bring some exquisite technical reason for this but sad truth is that there is any. The main goal of this setup is showing off.

In 2002 I went to the Rage Ghosts tour. It wasn’t the first time I saw Rage live (it may have been the fifth one I guess) but it was the first with Mike Terrana behind the drums. Mike is a real badass when it comes to put on a show, and I realize how much of that show came from the fact that I could actually see his face. He was there, staring at the crowd, making all kind of crazy faces and juggling his sticks all around like a super-powered cyborg heavy-metal clown.

Think over it a bit, it was not so easy in the 90s to actually see the drummer: deep power toms raised up in front of them, cymbals in the middle everywhere…

Can you spot Nicko anywhere? Mh, yep, there is hair there… maybe… but for sure you can see Mike high on caffeine! ;D

That was the moment I realized that, if you have a live activity, show matters!
I have to say that during my stage years this payed off a lot in terms of audience appreciation. The downside of this is that I made an habit in having a symmetrical setup and playing single bassed was no more an option.

That’s why when I first spotted a Giant Step Middle Pedal online, my mouse long lingered over the Add to cart button. Yet it was a sh#tload of money for a basically aesthetic upgrade and I never resolved to buy one until I began rehearse with my e-drum and decided to build a properly sized e-kick.

I managed to fit the small 8" Alesis kick-pad on the right side of the drum-rack so I could actually play my kit “centered”. When I decided to upgrade my e-kick to a full-size triggered bass drum, it stopped to be a matter of aesthetic… I needed a solution.

Evolution Drum Gear

I was OK with spending sound money for an off-set pedal like the Giant Step, up to 6/700 bucks and searching for Off-Set pedals I discovered Evolution Drum Gear, an European producer that was building great stuff under license (yes, the design is patented, which may explain why almost no big name produces such stuff, which is frankly pretty easy to do and — to me at least — makes perfect sense from a market perspective).

I wrote them to know if they had a reseller in Italy, where I reside, but sadly no, they had not. But they was OK sending me the stuff from northern Europe for 25 bucks more. Yay!

After a bit of chatting by mail they proposed me an endorsement, which was a real deal to me since I’m not gigging around anymore. Despite their kind offer and total availability we struggle to get in touch for over a month. My current understanding is that they are a really small company with a few really awesome products. At the time of writing their site is down and a couple of administrative links are there for anyone to reach. This adds to the idea they are still a small company, hacking their way to the real market.
Still I was eager to sign out the endorsement and pay for the product but I was also in a hurry so I had to (sadly) set my enrollment aside and go another route… with Sonor out of the middle business and Off-Set selling only overseas (no, I didn’t consider Sleishman… sorry but it’s too ugly to my tastes), the only way to go was DIY.

Pearl Demonator hack

Or how I payed less than 350 euros for a perfect middle pedal and two news single ones.

The idea of a DIY symmetrical double came from this rouge clip on YouTube: Making a middle / off-set pedal with Tama SpeedCobra. I accidentally saw that clever guy do the McGyver shuffle on that pretty expensive beast and pull the object of my desires out from the cylinder.

Too bad Speed Cobra is expensive, to the point where buying an equivalent industry product made more sense (not to mention that if I’d ruined something in the process I’d had to manage a really pissed off wife). Moreover I don’t like Tama pedals that much… I play Pearl pedals since late 90s and was currently using two single chain-drive Eliminator and a strap-drive double Eliminator on my e-drum.

During a visit to a local music store I spotted a Pearl P-932 Demonator. Something in its structure caught my eye. It should have been the two separated and perfectly symmetrical pedal posts on the main plate. I flipped the plate over discovering the bolts there to be taken off, right accessible by mean of holes in the rubber grip and perfectly symmetrical.
Demonator was not Demon Drive but they seemed really well crafted, robust and also pretty light.

It seemed easy enough to hack, flipping posts over and having the additional advantage of two beaters in the same position from the center of the head (ten points to Gryf… to Pearl Drums for this, it makes the difference when you are using a triggered drum).

Back home I investigated a bit more just to discover that P-930 series is one of that few fortunate products that make you wander why should you spend more for the big brother. And more important, I found this post on DrummerWorld where a guy did exactly what I envisioned.

Well, almost… because perfectionism, you know… :)

How it went

OK, so… disassembling this stuff is really a no-brainer. Proper Allen keys come with the pedal and all you need to break them apart is in the box.

The process however has a possible single point of failure, which is also a one way process: cutting the shaft in two parts. This means that once done you can’t just get back to a couple of “normal” double pedals without ordering a brand new spare shaft. It’s worth saying that it was priced 25 bucks to me by the guys of Esse Music Store, so it may worth the pain.

You’ll also end up with one untouched shaft,but the external part only, since all four hexagonal inserts had to be cut in half too.

TreeClimbingFeet (the guy who posted the stuff above) did a good job, but there were areas of improvement: the guy managed to cut the shaft in two parts but the inner joints were not secured with the proper tightening screws. This creates play between the external shaft and the insert and I feared that this can end up damaging both parts, by tear and wear.

The solution was to drill threaded holes in the thing, which if you have mechanical skills can sound trivial, but if you (like me) never tried to thread a hole… well, it sounds like you don’t have a second chance.

But luckily you do, since with two pedals come two shafts. I took my courage in both hands, called a friend to help with one additional hands+eyes assembly (:D) and did the job.

The results was impressively good, as you can see in the photos I took. Too bad I didn’t take any shot during the process… we were too focused on not brake anything.
But here is what I learned and all the advices I can give to do a great job!

Steps to reproduce

Disclaimer: Doing the cut and drilling is not hard, but you’ll need tools. And at least some basic skills in using them. If you already have access to them, yay! If not it can cost way more to buy them than to go to a mechanical workshop in your area: they are (hopefully) skilled pros and have proper tools. This can be the best option, actually. I guess it can cost you something around 25 to 50 bucks for a professional work, with industry-grade results.
Yet, if you have the tools at hand this is NOT that hard to do and you can then go telling everybody how great you are at hacking things (like I’m doing now :D).
Just please mind that
if you decide to do this you are doing it at your own risk and blah blah, so please don’t come back here asking me for refund or to honor your lost warranty.

With that out of the way, here is your shopping list:

Things you’ll need

  • Two (2) Pearl P-932 Demonator double pedals: I bought two of them from Esse Music Store (Italian seller) for a total of 330 euros.
    Claim: I have no relations with Esse, I’m just a normal buyer among others for them; still I wanted to credit those guys for the great service and the big deal. Kudos!
  • A set of allen keys: actually the necessary ones come with the pedal, but you’d better have also robust Allen inserts of the same size (stainless steel are ok) and an adjustable monkey wrench.
  • A rubber-headed hammer: you may have to persuade the cam to slip off the shaft despite the abundance of threadlocker…
  • A table clamp: it must be bolt on a workbench. It will hold your drive shaft in place during sawing and drilling. You’d better have also a rubber sheet or other “soft” gripping material so you won’t scratch the pedal drive shaft.
  • A hacksaw: I guess a robust fretwork saw can do but you’ll get best results with a metal saw with thin teeth.
  • A 5.5 mm drill bit for metals: and a driller of course. The best option is to have a drill press so your holes and threading will be perfectly vertical. I got great results without one but I sweat a lot.
  • A tap with an M6 threading bit.
  • A punch: to mark holes centers so your drill bit won’t slip away.
  • Lube oil: necessary (!!! NECESSARY !!!) for a polished drilling and threading.
  • Sandpaper: I used 160 for border rounding and 1000 for polishing the cut part.
  • An electrical grinder: I guess this is optional but will help a lot in taking that 0.2 mm away from the cut parts and make them straight and matching.
  • Threadlocker: to hold the posts in place virtually forever (please read on about this before doing yourself a major disservice, as I did).
  • Gloves: when you work with the grinder, please use gloves… if nothing else, since the aluminum will become hot!

Cutting the shaft

The Aeronautic Aluminum advised by the Pearl sticker on the shaft is a very light and rigid material. It is not soft (aka it will not bend) but it is easy to work. A simple metal hacksaw cuts trough it like butter, producing small crumbs and warming the metal just a bit. This is true for both the external shafts and the hexagonal inserts.

Proceed this way:

  • Measure the piece so you’ll cut it in the exact half (I used a simple ruler, half-mm precision); mark it out with a marker (I advice a 1mm marker, taking that millimeter into account) and draw a straight line all around the “circumference” to help keep your saw on a straight line. If I can remember correctly the center of my shaft was at 131,5mm (the shaft totals 263mm). Don’t take my word for it and take your metrics!
  • Put the piece in a table clamp: beware to put something like fabric or better yet gum/neoprene foam around it or you’ll ruin the surface permanently. 
    I kept the marker line 1mm out of the clamp so the clamp side itself can work as a vertical reference for the saw. Keep a bit of distance or you’ll hit the clamp side: repositioning the whole stuff during the cut is not something you want to do!
  • Use the clamp as a reference so the shaft is positioned horizontally. You can place a straight piece of wood on top of the clamp and use it as a frame against which to place the shaft… no matter how you do, be sure the thing is positioned straight or you’ll end up with a diagonal cut.
  • Now it’s time to saw: don’t press the blade! Keep going back and forth and apply little force. You don’t want to clamp the shaft too much or it will brake, but you don’t either want to press it until it snaps out of the clamp. If a friend can take the shaft free end so it is not in a lever, ask him to help. Again without too much applied force.
    The blade (be sure it is for metal, not wood!) should cut the shaft without that much effort. It should take 3 to 5 minutes to pass through it. Again, be gentle and take your time!

The same procedure must now be repeated for the hexagonal inserts. I took 65mm from the cardan joint, discarding the rest. It should sit in nicely. Don’t overcut but also don’t undercut them.

  • I then used the electrical table grinder to straight my cut and refine the cut-edges. I did the work by hand, with a bit of touch, to get a smooth top border, slightly rounded at the corners to better fit into the shaft. Again, don’t overdue, I’m talking about grinding away half a millimeter of material from the borders.
  • Refine the cut surface and corners either on the shaft and the inserts with 160 and 1000 sandpaper, to make them smooth and polished. This really makes the difference if you cut them by hand. You’ll have to inspect them close and accurately to see any rough edge.

When you’re done try to slip the inserts in either ends of your new short-shafts and check they can go all the way in. If such pat yourself a shoulder, you can stop here and assemble a TreeClimbingFeet version of the middle pedal.

If you want to go pro, follow along. :)

Drilling the secure-bolts holes

Keep in mind we are now working on the “flat top” of the shaft, where the holes for the tightening screws are. We have to drill two new holes at the end we created cutting the shaft in half. Let’s mark out the positions for both:

  • Again, the first step is to measure the distance between the holes. I remember the first hole border to be 3mm from the end of the shaft and the second hole border to be 10mm from the first hole border. The holes are 6mm in diameter, so let’s to the math…
  • Before adding things together: I kept the first hole at 5mm from the border and not 3, to avoid problems during the drilling: it’s better to have space. That said, measure 5mm from the cut border of the half-shaft, the add 3mm (half the diameter of the hole) and mark a straight line with your marker, transversal to the shaft. This is the position of the hole center with respect to the shaft length.
  • Now measure another 3mm, then 10, then 3 (half the first hole diameter, plus the distance between original holes, plus half the diameter of the second hole) and mark another straight line.
  • OK, we have the position of the holes centers along the length of the semi-shaft. Now you have to mark two little lines in the middle of the 6mm flat-top. If your shaft is like mine it has two ridges running beside the top. I marked my cross-line by hand… it was pretty easy to “see the center” in such a small area… you can take a ruler and do a more precise job if you want.

Now you should have two little crosses. It’s time to drill the holes!

  • We don’t want the drill bit to slip away, it would be a disaster! To avoid this we’ll punch a pilot hole in the right position. Use a 
    punch and a hammer. Place the punch in the right position and hammer it once (only once), with decision but not a lot of force. It works better if you use a heavy hammer and let it fall on the punch vertically instead of applying an active force. Do it for both crosses.

You now have to drill the hole. If you have a drill press and you know how to use it, glad for you! I had one but I wasn’t able to use it correctly, so we did the work by hand. This is where working with a friend can really make the difference, since you want to be sure the holes are as vertical as possible. Let’s go step by step.

  • Put the shaft back in the clamp, again, don’t tighten it too much and protect it with some soft but not slipping material.
  • Put a bit of lube (oil is ok) on the pilot holes you made. Drilling metal requires lubrication since the aluminum crumbs must be taken away by the flutes.
  • Use the 5.5mm drill bit. The hole must be a bit smaller than 6mm so it can be threaded to measure. This is IMPORTANT!
  • Take position well over the clamp, so you can act on the vertical. Doing vertical hole is important! Since we didn’t use the press, my friend stood on a chair, with a foot on the working table to be stable and act from the very top. In the meantime I was kneeling in front on the table, looking at the bit from the sides and taking the drill vertical with both hands.
  • Before drilling you have to know that metals require SLOW rotation speeds! The harder the metal, the slower the drill. We used the lowest possible speed and took our time. Now again, do not apply much pressure! The driller will work without the need to be pressed hard against the shaft. Of course you want to press it, but don’t overdue. GO SLOWLY!
  • During the process stop often to apply lube. Don’t hurry and do things well. It should take 3 to 5 minutes to drill the hole, and there’s nothing bad. Sure pros will be laughing at me now, they can drill a hole in 3 seconds, but I prefer to take my time and play safe. If you, like me, are not pros or have no skills in mechanics, there is nothing bad in doing things this way: it is your skin in the game after all.

Do this four times, two for each half-shaft. Done? Almost! :)
Let’s thread the holes!

Threading the holes

Here you’ll need the tap and the M6 threading bit. The operation is simple but again: it’s important you go vertical!

  • Apply lube to the threading bit and hole. Again this is important!
  • Place your tap on the hole, ask your mate to help you keeping it vertical and gently screw it into the hole. It should not require much effort and at a certain point you’ll have the feeling you are just screwing a screw… this means you finished your threading. Unscrew the tap and you’re done.

Test the hole with one of the original threads. If it goes down vertically and can screw all the way down to the ridges, pat yourself the other shoulder!
The hard part is over! :)

Here is some shots of what I ended with:

Honestly, can you say this was done by hand? :) If you have access to a mechanical workshop not even a Pearl engineer will be able to tell the difference! :)

I really want to credit my friend Dario for the help in this process. Without him I wouldn’t have had any chance.

Assembling the pedal

The rest of the operation is pretty straightforward. The only thing that took me a while has been to remove the beater holder from the stand shaft that needs to be turned around (from left to right position).

It is very tight and you’d better use a couple of screwdrivers as levers on both sides of the shaft. I also had to use a rubber hammer to keep the thing off. I really feared to break it at some point but I managed to get it out. Brrr…

I think it was thread-locker’s fault. All bolts and screws have been fixed with that product and a bit of it dripped inside the shaft, sticking it to the beater holder. Anyway, once this is done the rest is just turning an Allen back and forth.

Here beside you can see a shot of the part I’m talking about. The beater holder has to be turned around and despite the shaft is really short, it has been a real pain to separate them.

For the rest it is really a no-brainer. I took some image during the assembly phases and you shouldn’t have any problems figuring out how to do it by yourself.

As I said in a previous post my man-cave is actually underground so these shots quality is really awful. Sorry for this, hope you can make something out of them anyway.

The results of the first step looked like this. As you can see the central plate is a master-pedal plate, with all screw holes and a bit too space taken. But all in all the result is great.

One more step towards perfection: the custom plate

Playing this toy made me realize that despite my cherished P-2000 Eliminator topped the Pearl products range, years passed and today middle-range products can be comparable if not better that old glories.

Since I sold my P-2002 right away (it was really easy, and this adds to the value of the product itself, I guess) I now had two P-2000C singles for my double bass setup and a P-932, although hacked, for the other setup.

But most important, I had a complete P-930 single pedal left from the hacking and all the pieces to build another if not for the base plate and hoop clamp that was in the middle of the hacked assembly.

I was clear to me from instant zero that I had improve the design again!

What I needed then was:

  • A spare base board
  • An additional spare clamp

Esse Music came to the rescue again with the clamp: 14 euros for the assembly, with bolts etc. It took a while to get (almost one month) but in the end I got it.

The base board instead was not available from the distributor and it would have took 5 months for a delivery. The cost would have been 50 bucks.

I took this over and tinkered with the possibility to build a board by myself. I headed to a rapid prototyping service, expert in laser-cut and their quotation for the work was 60 euros… I was facing a similar price tag but could have received the stuff in days, not months.

Talking about this with a friend working in the metalwork industry, he told me that such a design was a breeze to do in his company workshop. It took a while because they don’t work for privates and had to wait for a 3mm thick stainless steel foil to go into the cutting machine, but after a month, the plate was ready; I received it almost at the same time of the clamp. I just had to produce a depiction with measures that my friend then transformed into a CAD project. It took one hour to me and five minutes to him, it seems… Here is some illustration of my work and his one, just so you can learn how little talented I am with this stuff :D

I’ll ask my friend for the CAD project so I can share it with anybody interested.

The plate was laser-cut, drilled and sand-colored for maximum duration. I then assembled the posts over it, cut a 3mm PARA-rubber foil to place under it (original plates has a 3mm thick black rubber grip foil and I wanted to keep the plate the same height) and here is how it looks:

The small orange square in the last shot is an additional PARA piece to avoid scratching the black surface with the hoop clamp key.

And the final byproduct of this extra effort is this:

Two brand new P-930C Demonator, there to rock my next gig!

Talking about this last part of the project, it is time to give a sage advice learned out of a bad experience.

When I assembled the first version of the pedal, with the original base plate in the middle, I used some (I guess too much) threadlocker to keep bolts in place. I was already thinking about the custom plate improvement but I was almost sure I would have bought a spare plate so I didn’t considered having to unscrew the bolts.

Well, pay attention to that stuff!!!
It has been a hard time unscrewing the bolts and I never want to repeat that experience again! I tried to warm the bolts to 250 degrees to make the locker burn and crumble, I tried with force and two Allen keys snapped broken in my hands (I also risked a small injury). That stuff is TOUGH!

I was about to give up (didn’t want to ruin the thread in the beater posts) when I took one last chance. I used a steel insert and an adjustable monkey wrench to create a sort of long-lever Allen assembly. Even with a 25cm arm I had to apply a lot of force to get the bolts out and had to buy a couple new bolts since the head of the original ones was ruined, twisted by the momentum.

After that I was able to place all the stuff back again, the post didn’t suffered for this. Still I have shivers down my spine thinking at that moment.

So my last advice: use a threadlocker to keep things firm but:

  • Do it only in the end of all your work.
  • Use a couple of drops over the bolts side! I exaggerated with it, dripping several drops in the threaded hole.

Aside from this adventure, I appreciate I had a lot of luck! Having a friend that crafted a custom board for free was a real boon (thanks Alessandro!) but in the worst case I could have reached the same goal with 60 euros spent in rapid prototyping or (in a different moment of the year maybe) buying another plate for 50 euros.

Was it worth the pain? I hated the idea of having an almost complete single pedal lying there abandoned, so to me: yes, it is worth it all for sure. Towards the end of the post I’ll do some math about how this did cost to me in total and you’ll have an idea.


P-932 line seems to be the best candidate for this kind of hack, at least in the 3–400 bucks price range. If you plan to to this on a P-3002 Demon Drive double my advice is to not doing it and spend 700 euros for an Evolution EOSP-E1S pedal: it is already done, it has warranty and it comes with all bells and whistles… not to mentioned two P-3002 will cost over 1K!

On the other hand this hack can be quickly reversed, at least to get a single “normal” double out of the middle version. I still have a full sized shaft and inserts — although cut — are long enough to use it as a double pedal if the need be. Buying two new shafts to completely reverse back to the original products would cost 50 euros, more or less.

One more boon is that you’ll be left with a full single P-930 and another one but the pedal plate and hoop clamp.
As I shown you can convert the leftovers to two fully functional P-930 with for a small price.

This means that with less than 400 euros you can get away with:

* A brand new, robust Peal middle pedal
* (Possibly) a standard P-932 double, if the need be
* Two P-930 singles

Now a bit of math: I will probably sell my two old Eliminator for 150 bucks in total and will use the new Demonator singles. I already sold my good old P-2002B within a week for 160, so if I manage to complete the selling I will have spent something like 50–70 euros in total (and circa 8 hours of spare time) to end up with a middle double I can convert to a normal double in less then half an hour.

Not bad at all! ;)

I played it for a couple of months now and have to say the feeling is great. This stuff is really fast, way faster then Eliminator (that was a bit heavy compared to this) but doesn’t seem it will break quickly! Construction is sturdy and the footplate is light but robust. It is also a longboard style, with no heel plate: it’s not as long as the Demon Drive or Axis but it is quite an improvement over the P-2000 series, if you ask me.

The last noticeable boon is that I can use it live in a single-bass setup. It happens, even if I tried to make it happen as little as possible for the aforementioned “showing off” habits.
Instead my current attitude is exactly the opposite: I’d like to have a new single bass setup, built from the ground up with the idea of be gorgeous in a live show. You can keep your (maybe decorated) drum head in front of the crowd and taking “the Terrana position” at the same time, positioning your cymbal arms so that your are well visible on the stage.
This can sound a bit showy but hey… that’s how I want it to be! :D

In conclusion, if you need, or ever dreamed of a middle pedal like Giant Step, Off-Set or Sleishman, but don’t want to spend too much for such a beast, this hack will make you happy.
I actually am and I’m already putting this stuff to good use with the band!

If you have any question, feel free to contact me. I’ll try my best to help.