Tuesday, January 26, 2016

The Pedal

At this point, the vibraphone is about 98% complete. All that's left to make is the pedal and the dampening system. If you didn't know, all vibraphones, in their default state, are dampened. This is done by a padded bar that pushes up on the keys in the middle of the frame where the natural keys and sharp/flat keys come together. The dampener is attached to a spring system that lowers it so that it's no longer in contact with the keys, letting them naturally ring when struck. This whole dampener and spring system is controlled by a pedal at the bottom of the frame that you push with your foot.

To make this pedal, I just happened to have a scrap piece of wood that was wide enough. I rounded off the corners on the end closest to your feet.


I couldn't just directly attach this pedal to the support beam running along the bottom of the frame because that beam sits a little too high and you would have to pick your foot up off the ground to push it. I had to build an extension to lower the resting position of the pedal. It's just small square blocks screwed into each other with another support beam connecting them at the bottom where the pedal will be attached. The pedal was attached using 3 door hinges.




Here is the whole instrument with the pedal installed.


Saturday, November 28, 2015

Resonators Part 2

The next step is to rivet each resonator to two aluminum beams. Rivets are used because it's much cheaper to buy over 100 rivets than to buy over 100 nuts and bolts. Also they don't protrude into the inside of the resonator very much. 



I made these anchor blocks with slits for the resonator support beams to rest in. 





And of course, painted black. 









The only thing left to build is the dampener bar and pedal, which could be very complicated to design.


Thursday, November 19, 2015

Resonators Part 1

It has been a struggle to find time to work on the vibe. In October I moved out of my parents house 30 minutes away. So I still have to go to their house to work on it. I decided to make the resonators into 2 posts just because it might be a while before they're completely done.

The resonators are being made out of PVC pipe as it's cheap and very easy to work with. It actually doesn't matter too much what your resonators are made out of to properly resonate the bars.


I tune them by sanding off bit by bit from the open end until I have the correct pitch. I check the pitch by hitting the capped end with a mallet. It isn't too big of a deal if the resonators aren't tuned as precisely as the bars were. In fact, the resonators were quite difficult to tune. Temperature affected them very much and I would get pitch readings all over the place on many of the pipes. I just tuned them as close as I could.


The pipes ended up appearing much shorter than typical manufactured vibes. But they are the correct pitches and they actually do a great job of resonating a note, especially on the low end. On the highest 4 or 5 notes, you can't really tell a difference between the sound of the note with or without a resonator.

I cut out these notches on the tops of each pipe. Eventually I will add a fan and motor system and this is where the fan rod will rest. But that's more of a stretch goal to tackle after the rest of the vibe is completed.




Monday, October 26, 2015

Additions to the frame

I added a support beam connecting each end board at the bottom for extra stability. The pedal will also eventually be attached to this beam.



The string hooks need some type of buffer between them and the keys, otherwise metal would be rubbing against metal. You can buy latex tubing on Amazon that works perfectly for this purpose. Even when the key are touching the latex, it barely dampens the bar at all. The tubing also elevates the bars even higher off the frame. 




I made a video to show how long these keys will resonate even without resonators. 



Next up: resonators. I've already tuned the first 6 of them as of posting this. 



Monday, October 12, 2015

The Frame, part 2 (staining & assembly)

Staining the wood was actually quite enjoyable. I've seen from many different sources that it is very difficult to stain pine evenly. I tested the stain on some scrap wood and I was pretty happy with it. For the stain I used the Minwax Dark Walnut stain.

 After the stain dried I applied 2 coats of Watco Danish Oil Wood Finish. My pictures with the lighting conditions don't show the stain very well. I was very pleased with the finished result. There were a few blotchy spots where the pine unevenly soaked up the stain, but it's not terrible.



I then had to assembly all the parts of the frame. It came together quite nicely for the first time. I did have to add 2 additional bolts on each end board to provide stability. I will add a support beam connecting the two end frames from the bottom. The pedal will also be attached to this beam. I also painted and screwed in all 88 screw eyes to suspend the bars. I bought black latex tubing that I will cut into small pieces and stretch over each screw eye to better suspend the bars and to serve as a buffer against the bars.









This is now the second big milestone that I've reached in the project. The first being tuning the keys. 









Monday, September 28, 2015

The Frame

I've been working on the frame for quite some time now. It's coming together really well. I came up with a height adjustment system using telescoping, perforated, square tubing I found at Lowes. 




I cut out squares for the tubing to fit into the wood. They will also be bolted down with brackets.


Here are all the parts for the height adjustments system. I'm painting all hardware black.



This is about 90% of the base structure of the frame. I won't put it all together until I sand, stain, and finish the wood. Not included in this picture is a support beam that will run the length of the board in the center along the bottom. The pedal will also eventually be attached to it.


Thursday, September 17, 2015

Fine Tuning

The keys are finally completely done. The fine tuning process was meticulous. I first tuned each bar down to where my tuner was telling me was in tune, but I knew they were not actually in tune. This is because the ambient temperature in my garage along with drilling and sanding raise the temperature of the bar and cause it to lower in pitch. So when my tuner tells me it's it tune, it was actually around 3-5 cents sharp of the desired pitch. So I had to let the bars settle in room temperature for several hours and then check their pitches indoors. I made a table to make the process a little easier. each column represents different times I checked the pitch of the bars. For some of the columns I didn't make any adjustments. I just wanted to see if having the ceiling fan on or not affected the pitch, which it actually did to the degree of around 0.2-0.4 cents, which really isn't enough to worry about. For several times I repeated this process of making small adjustments, settling at room temperature, and then checking the pitch until all the bars were in tune. I tuned each bar to be less than +/- 0.5 cents of the desired pitch. I couldn't really tune more precise than that because my tuning app was so precise that it showed small differences just by the speed of the fan in the room where I kept them. But I tried to keep similar conditions each time I checked pitches. Here's a scan of the chart I made.



I don't really have any new pictures of the keys to show because most of the adjustments were so small. However on a few keys, I had to make drastic adjustments like this one:



As I type this I'm actually almost done building the main structure of the frame minus the resonators and dampening/pedal system. I won't have a picture of the frame put together until I sand, stain, and finish the wood. Then I'll actually fully assemble it.