Skip to main content

Repairing the Roland HD-1 V-Drums pedals

I have a Roland HD-1 V-drum kit that is about 15 years old.  It was sitting for years when I got it, and when I put it all together it was clear that the pedals were not working.  Boo!  Time for a repair.

Roland HD-1 Pedal Hammer under a Heat Gun.

How the HD-1 pedals work

With the Roland, a pedal actuates a variable resistor.  When you step on a pedal, it presses on the variable resistor.  Putting force on the pedal reduces the resistance of the resistor. A little force results in a small decrease in resistance.  A high amount of force greatly lowers the resistance.  The HD-1's computer detects this and makes the appropriate sound.

There are two important parts to this mechanism: the electronic resistive strip, and a rubber hammer which presses on the strip in a variable way. 

There is no internal difference between the left and right pedal. The guts of each pedal is identical. 

Where it goes wrong with age

Looking at mine, the problem was with the aged rubber hammer. Originally the hammers were very flexible, but with age they became very hard, and therefore stopped pressing on the resistive strip.  That led to poorly functioning (or non-functioning) pedals.

My variably resistive strips were fine and did not need replacement.  I'd keep the original resistive strip in place unless it is damaged or very worn out.

Repairing the HD-1 pedal hammers

The solution is to use hammers that are as flexible as they were when new.  I softened my hammers up using a heat gun set at 250 ºC.  After 5 minutes in hot air, the hammers became much softer.  Surprisingly, they remained soft long after they cooled.  I guess that's the magic of this class of material.

The central hammer surface [marked up here in orange] variably presses on the resistive strip. No flexing means no change in resistance.
 

Reinstalling these softened hammers with a small amount of silicone grease on the mating surfaces fixed the problem.  

Heating the hammers may be a temporary solution, as the hammers might harden up in short order.  A longer-lived solution may be to buy replacement hammers. I bought replacement hammers on Amazon, as noted here.


Labels:

Popular posts from this blog

Fixing a SodaStream Jet, part 1: Disassembly Guide

I've had my SodaStream Jet for years, and once in a while something has gone wrong. Disassembly is the first step to repair.  Start with this article to see how to disassemble the SodaStream, and then once you have that down, scroll through my other articles to see how I repaired specfic SodaStream problems. SodaStream Jet Disassembly Guide Tools Required Flat head screwdriver Phillips head screwdriver 1. Remove the Carbonator.  Duh. 2. Remove the black panel lever The front big black tilt lever needs to be removed first. Removing this panel is tricky, but it isn't impossible. Looking up at the bottom of the black panel, there are two tabs, one on the left and one on the right. These tabs fully secure the panel in place. The trick is to use a flat-head screwdriver under the plastic to gently lever the tabs out of the way.  Note in the pictures how I approach these tabs with my screwdriver.  I usually release the left side first, and then I release ...
Read more

Fixing my Wahl 9918 Groomsman Beard and Mustache Trimmer

Not everyone would bother repairing a $25 beard trimmer, but why not fix something for under $5 instead of spending another $25? My  Wahl 9918 Groomsman Beard and Mustache Trimmer  has admirably performed its beauty duty for many years, but the time came when the battery just wasn't holding a charge any more.  Most people would just put the trimmer in the trash and buy a new one, but I figured I could repair my otherwise excellent Wahl and save some money. In fact, even high priced trimmer and rotary shaver brands, like Norelco and Remington, can be easily repaired using a process similar to the one I used to fix my Wahl.  Read on to find out how. I opened up the Wahl by popping off the black plastic faceplate with a tiny flathead screwdriver, which revealed two screws.  By removing the two screws I was able to easily open up the unit, revealing the guts of the device. Backplate off, Revealing the screws The internals are rather simple: a motor, a...
Read more

Sodastream Carbonator Leakage, Usage, and Weight

SodaStream 60L "Carbonator" CO2 cylinders have a specific weight when empty, plus about 410 or so grams for the CO2 they should have when they're "full".  A little while ago I went to buy a replacement Carbonator from my local hardware store. The dealer pulled a new Carbonator out of the box and sensed it was lighter than usual.  He put the "light" Carbonator in the "empty" pile and sold me a different one.  At that moment I concluded that it would be smart of me to weigh both new and empty SodaStream carbonators.  Here are the results. Weighing a SodaStream Carbonator - for both Science and Consumer Protection.       The dealer told me that sometimes the carbonators leak after they leave the SodaStream filling facility.  That means there could be an opportunity for customers like me to get ripped off! The SodaStream cylinders I buy claim to have a net product weight of 410 grams - and that means that a full Soda Stream Carbonator shou...
Read more

Macintosh: Upgrading an eMac

It's been a long time since I wrote this article, but the fact remains: The good old eMac can still be useful if you take the simple steps to keep it as good as it can be.  All can run Tiger, and most can run Leopard - great operating systems for their day with a bit of useful life.  This article describes the procedure I used to upgrade my old eMac, including: Replacing the internal hard disk with a large capacity drive. Increasing the memory for performance Upgrading the operating system Here I'm upgrading a 700 MHz eMac, but the procedure and tasks for upgrading other eMac models should be almost identical. Upgrading versus Replacing My sister's eMac is of the 700 mhz variety, with 256 MB of memory. The machine seemed to be getting "slower", and the original 40 GB disk was becoming jammed packed with photos and iTunes, and within a few months she'd be out of disk space. There were two options to address the problems: upgrade the eMac, or go o...
Read more

Robust Installation of an HDHomeRun Networked TV Tuner. 64 OTA channels!

I added an HDHomerun (HDHR) over-the-air (OTA) streaming box to my home network, bringing over-the-air broadcast TV to my computers, phones and tablets.  The HDHR is a big upgrade from my previous setup: using a simple "window mount" antenna directly connected to my TV. A TV-attached antenna is good for watching some TV for free, but the HDHR offers so much more flexibility. Figure 0: HDHomeRun on my basement wall   My original OTA TV setup was haphazard at best. It was finicky, ugly, and hard for other people at home to use. I would actually tape my antenna to a window whenever I wanted to watch OTA TV. Plus, it only worked on my TV and not with my other devices. I wanted a cleaner and more modern OTA setup. After looking at possibilities, I developed two goals: (1) bring my OTA TV into the modern Internet-connected era, and (2) set it up in a reliable and pretty way so that other family members wouldn't have to fool around with the antenna or anything else.  With that,...
Read more

Adding a Water Flood Sensor to my Vista-20p alarm system

My Honeywell Vista 20p alarm system is fairly comprehensive, but I want one more feature: an alarm that lets me know when my sump pump isn't working properly. Here is how I added one for about $8 in special parts.   I'm afraid of a flood in my finished basement. I'm fortunate - my basement sump pump system is already redundant, with two independent pumps and two outflow pipes. The primary pump kicks in when the water level reaches 6 inches, and if that doesn't work, then the backup pump kicks in when the water level reaches 7 inches.  The backup pump should never kick in unless the primary pump is having a problem pumping.   But there is a problem with this setup: I might never know if my primary pump has failed, leaving me with no redundancy.  I want to be informed when I have one (or god forbid, two) pump failures. My goal is to have my Vista 20p alert me when the sump's water level is ever beyond the point where my primary pump should have kicked in, alertin...
Read more

Other Posts

Show more