Category: Timpani

Adams’ Universal Problem (part 1) (Job No: 1243)

The Adam’s universal timpani are good little drums, the best thing Adam’s make, but they do have one major problem.  The owner of these drums has decided to get me to rectify the problem.  So what is it?
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In a nutshell, when you change pitch with the foot pedal, it doesn’t pull in the centre.

The bowl sits in a cradle that has three legs and a pedal incorporated.  The pedal is a big lever that is attached at the back of the cradle.  The central pull rod is attached to this lever, which becomes a fixed point along the length of that lever.  As the lever moves, that fixed point travels through an arc, not just up and down, so in relation to the centre line of the drum, is moves forwards and backwards.  Furthermore, this fixed point is actually slightly to the front.  Neither of these things is going to give consistent tuning, and is a massive schoolboy error – but just see how many other makes of timps have the same issue, at least this make can be resolved.

In the picture above I am actually recording set up measurements so that the drums get put back together correctly, but it demonstrates the problem perfectly.   I have dropped a rod down the centre line of the drum, and I’m recording how far the spider is pulled by the pedal.  Looking closely, it is clearly visible how far from centre the original fixing point is by the size of the angle between the two rods.

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So what I do is to separate the central pull rod from the pedal by making a secondary linkage, but as you can imagine, it is a little bit more involved than that.  These posts are essentially one days work.

I need to take lots of measurements, which use lots of tools that have been made specifically for the purpose – so many tools that I need to do a job simply are not available.  For instance, below I am measuring how much vertical movement down the centre line I will get on the new mechanism.

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Once all measurements are taken and everything is removed from inside the drum, I can locate the centre of the bowl.

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My design fixes the central pull rod in the centre at the base, and guides it vertically with a guide block.
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The bowl is removed from the cradle and the base casting can be prepared and modified if needed to accommodate the new design.
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Now I can fit the guide block and reinstall the bowl ready to start work on the next stage tomorrow.
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The story continues in Adam’s Problems (pt 2)

Premier Concert Timps (Job No: 1246)

When I overhaul a set of timps, there is a lot of work involved over a period of days or even weeks. My approach is to fix everything properly; I am after all a professional and that is what I am being paid to do. However not everyone is as conscientious, and in the end, you get what you pay for. So when I work on timpani, I am fixing problems associated with wear and tear, and the dogs dinner that the previous person made of the job. The posts on timpani pick out examples of problems I encounter, rather than me writing, and you reading the same thing every time I do a set of timpani (which is why I have coloured this bit blue).

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So I did the usual process on this pair of drums: strip everything off the drum, so that whilst the castings are being welded I can work on the mechanisms.

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Then after the base castings are back and painted I can get straight into the rebuild and setup.  At the end of the rebuild, the bowls go in, and the heads are put on.  I usually do the counter hoops with the mechanism, so the bowls are the last thing I look at.

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Which is why it is so annoying when the PTFE tape is removed from the rim to reveal big bloody holes!

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As you can see above, these holes are deep, also notice how dry the glass fibres are (I’m lifting them up with the Stanley knife).  If you zoom in on the photo, you can see that there is a gap between the outer layers, and inner layers.  In fact, large areas were cracked and had to be removed, so the bowl ended up looking like this:

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So is this Premier not making the bowls properly, or customer damage?  Well it is a bit of both.  Yes it took a bit of abuse to actually break the outer layers into the void, but there should be no void in the first place!  If I had made these drums, even if, like these they were made in the mid to late 1980’s, I would repair them free of charge under “my lifetime guarantee” because they clearly were badly made.
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And finally, above is a very dusty, but repaired bowl.  Now I can finish the job and put the heads on, grrrr!

Premier Concert Fibreglass Timps (Job No: 1237)

When I overhaul a set of timps, there is a lot of work involved over a period of days or even weeks. My approach is to fix everything properly; I am after all a professional and that is what I am being paid to do. However not everyone is as conscientious, and in the end, you get what you pay for. So when I work on timpani, I am fixing problems associated with wear and tear, and the dogs dinner that the previous person made of the job. The posts on timpani pick out examples of problems I encounter, rather than me writing, and you reading the same thing every time I do a set of timpani (which is why I have coloured this bit blue).

This set is a bit of a mixed bag of types of timpani, but the fibreglass bowls need repairing which gave me the opportunity to try and explain what is going on a bit better.

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The knife is pointing at a little bubble in the rim of the timp bowl.





The other bowl in the pair also has problems on the bearing edge.

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After everything is clean and dry, they can be filled.





It can now be seen that the previous repair on the second bowl was also not right, it was a low spot on the bearing edge.  The filler I used is still visible sat on top of the old grey filler, which means that the grey filler was below the line of the rim.

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Premier Series 1 Timpani (Job No: 1228)

When I overhaul a set of timps, there is a lot of work involved over a period of days or even weeks. My approach is to fix everything properly; I am after all a professional and that is what I am being paid to do. However not everyone is as conscientious, and in the end, you get what you pay for. So when I work on timpani, I am fixing problems associated with wear and tear, and the dogs dinner that the previous person made of the job. The posts on timpani pick out examples of problems I encounter, rather than me writing, and you reading the same thing every time I do a set of timpani (which is why I have coloured this bit blue).

Very frequently I get jobs in to do that have obviously been repaired by someone else in the past.  We all have different standards, budget constraints, levels of knowledge, skill and methods.  All that I accept, and it is useful for me in order to evaluate what I do.  However sometimes I almost laugh in disbelief at what I am seeing.

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I can see why they have done this – the base casting has practically worn away, but ignoring the facts that it won’t work, and it has been done really badly, it looks bloody awful.

Removing all of that mess in itself is a job.  What it reveals is the state of the castings prior to the last repair.  To me it looks like no preparation was done at all.

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So all the sharp edges need to be filed smooth, and some of the bits that look solid, are in fact like tin foil.  What I need to do the job properly is solid metal.

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Now at least when the repair is done there will be clean lines and it will look good as well as actually doing the job.  All it takes is a little bit more effort and time, and respect for other peoples property.

These will now go out to be aluminium welded, so the post will continue.

Premier Elite Timpani (Job No: 1215)

At the top of Premier’s timpani range are the Elite series.  I like the Premier design, there are a few issues like they don’t sound the best on the (mass produced) market of orchestral kettle drums, but they are in second place.  What I like about Premier drums is the old style pedal mechanism.  The other great feature on Premier Elites is the universal tuning adjustment, or crown wheel.  The only real issue with the Elites are the extended collars.  After discussion with leading timpanists, we think at 1.1/2″ it is a bit too big.  However, I have yet to prove the hypothesis, it’s just from observations. 

I will expand these points in a specific blog post at some point.

When I overhaul a set of timps, there is a lot of work involved over a period of days or even weeks. My approach is to fix everything properly; I am after all a professional and that is what I am being paid to do. However not everyone is as conscientious, and in the end, you get what you pay for. So when I work on timpani, I am fixing problems associated with wear and tear, and the dogs dinner that the previous person made of the job. The posts on timpani pick out examples of problems I encounter, rather than me writing, and you reading the same thing every time I do a set of timpani (which is why I have coloured this bit blue).

These drums have been sent in for overhaul before things have deteriorated too far.  The mechanism is very dirty, but not rusty.  What they do obviously need is a bit of work on the copper bowls.

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One type of problem are big dents in the bowls.  This is no big deal, and is the sort of thing I just repair as I am going along.  They look bad, but in terms of time it doesn’t take too long for me to knock out (5 to 10 minutes)

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The finished thing.  There is a happy medium with this work.  If there is a hard corner, then that will always be visible unless the bowl is completely refinished because the copper and the lacquer have been over stressed.  With the dent, I find it is a case of the more you do, the worse it gets, so I take my time and consider each blow with the hammer.

The second type of damage that happens to the Premier copper bowls, is when the bearing edge is dinted when they are struck with the handle of a timpani mallet.

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As the handle strikes the edge it pushes material inwards in the centre, which raises the edges.  In the drawing this effect is exaggerated.

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At the top there is a playing dent, lower down looks like a flight case has been dragged over the drum.  This is what happens to percussion instruments, no care and certainly no respect of the fact that they are musical instruments.

After taking off any sharp edges that are above the line of the profile (positive), the negative indentations can be filled.

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The filler comes above the profile, so can then be cut away to the desired level.  It is then polished up.

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After all repair work is done, I polish the whole of the bearing edge to a shiny finish.  What I am after is a smooth surface that the skin or plastic can slide over.  Any marks can create a scraping noise as the head passes over them, which due to the tension and resonant chamber, is then amplified.

Premier Pro Symphonic Timps (Job No: 1209)

Premier Pro symphonic timpani are just like elites but with a standard collar. Gibberish! Elites are top of Premier’s range of timpani, they have a fine tuning wheel under the bowl, and the counter hoop is three inches oversized, meaning three inches bigger than the bowl. This is the extended collar. Therefore the Pro symphonic timps are identical with the exception that the counter hoop is only one inch bigger than the bowl, which is referred to as “standard”. The use of the term collar originates from the days when calfskin was predominantly used on drums, and it is the amount the head is stretched down below the bearing edge.

When I overhaul a set of timps, there is a lot of work involved over a period of days or even weeks. My approach is to fix everything properly; I am after all a professional and that is what I am being paid to do. However not everyone is as conscientious, and in the end, you get what you pay for. So when I work on timpani, I am fixing problems associated with wear and tear, and the dogs dinner that the previous person made of the job. The posts on timpani pick out examples of problems I encounter, rather than me writing, and you reading the same thing every time I do a set of timpani (which is why I have coloured this bit blue).

The heel on the base casting is prone to wear. It is the third point of contact the the floor, the other two being the casters, so when the drums are moved the heel can drag. As the heel wears away the tuning mechanism beneath the base casting starts to foul against the floor, which obviously is a problem. Easy fix, just screw a bit of something to the underside of the heel. And this is what happens to that solution:

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As can be seen, one has survived, one has fallen off leaving steel spikes, and one has been gone so long the steel spikes have worn completely away. A 30% success rate is just not acceptable to me, neither is having those steel spikes! Why have they come off? The answer is simple, the repairer didn’t know what they were doing. As the plastic heel drags on the floor it is applying a sheer force to the screws, and screws are very weak in that direction, so they “sheer” off. Secondly, plastic is softer than aluminium, so it is never going to last (durr)!

So the first major obstacle is trying to get the sheered, hard steel screws out of the soft aluminium which is not easy, and can sometimes take an hour. A frustrating, horrible job. Then I have a new block of aluminium, to bring the thickness back to original, welded to the castings.

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From the top side, it can be seen that the heat from the welding burns the paint.

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Which is then cleaned up and masked off, ready to be painted.

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As the drums are moved about, the struts can work loose, so they need to be tightened up. This requires a bit of feel – it is a steel screw into an aluminium casting, and aluminium doesn’t hold a thread very well. I commonly find screws that have stripped their threads due to being overtightened. Now sometimes I strip a thread, but I replace the bolts. The problem is exacerbated by the wrong bolts being fit in the first instance – Yes that is a manufacturing defect regardless of age. Because I am a genius, I buy the longest screws that fit!

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As Premier were developing the timpani various improvements were made. One issue was that on the larger drums, the heads were at such low tension, they had insufficient power to lift the pedal mechanism. Other manufacturers have a balanced action to overcome this problem. Premier went the same route and fit a spring to help lift the pedal. This is seen between the mechanism and casting on the left hand side.
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This spring was also insufficient in power, so a more powerful spring was fit in a new place. This is what I have retro fitted to this mechanism.
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The casters that are fit to Premier timpani don’t work. The route cause of the problem is that the casting was designed at least forty years ago for casters which have long since become obsolete. It is the brake lever on new casters that catch the frame. Premier fit spacers to lift the casters (bad idea from a mechanical engineering standpoint) and even ground away part of the casting.

Being a self proclaimed genius I use casters that fit, and they are the same as used on ludwig drums. However they are not available in europe, so I have to import them by the hundred. Once I have converted the drums to accept them, replacing the casters can be done by the customer.
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Premier Elite Timps (Job No: 1208)

A set of four Premier Elite Timps in for an overhaul.
After checking the range, I dismantle everything so that I can work on the parts at the bench.  At this point the chassis go out to have the heel blocks welded in, so whilst they are away, I can still work on the mechanism.

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Everything is stripped down and cleaned, inspected and repaired, modified or adjusted.  Attention to detail is essential for the drum to sound good and play nicely over the long term.  An example of this approach is the pedal.

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Missing parts are replaced or made. These are the spacers that act as the fulcrum inside the pedal. They should be held solidly in place in the pedal arm, and the pedal moves freely, but on virtually every drum I see they are loosened to enable pedal movement. This causes a whole  host of problems.

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The root cause of the problem is the pedal casting, which varies in size due to the nature of casting. The width of the pedal is reduced with various metal working tools, but provides a good opportunity to get the cheeks perpendicular to the hole.

However the hole being too small (or the barrel too large) is a manufacturing error by Premier.  The easiest way to rectify it is to ream the nylon spacers to the correct diameter.

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Above are all the bits ready to go back in the chassis.

Premier Timpani (Job No: 1062)

A set of 3 Premier fibreglass concert timpani to be over hauled. The usual problem with Premiers – the bowl shifts in the chassis. This is a bad example where the bowl is actually being pulled into the inside of the suspension hoop. These types of issues will affect the tonality across the playing range but one part of the range may well be in tune.

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Counter Hoop
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Cleaning of the old, incorrect, counter hoop felt and glue residues ready to be replaced correctly. First the hoops will be checked for loose parts and that they are flat and round. After final clean, new felt will be inserted. The counterhoop is like the nut on a string instrument, bad implementation will create a vagueness in the note.
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The counter hoop (above) is not flat. This is a universal problem with counter hoops. In application they bend down at the tension bolts, this means that the tension being applied to the drum head between the bolts is less than at the bolts. The bearing edge or rim of the bowl in acoustic terms is a nodal point, where the amplitude of a sound wave is zero. The centre is an antinode, where the amplitude of the sound wave is greatest. In order to achieve a harmonic note in a membrane (drum head), the nodal point needs to be round. Therefore, the effects of the counter hoop flex can best be visualised in the diagram below:
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The variation in tension has created a wiggly edge to the nodal point. This creates problems when putting on a head and clearing it (removing overtones).
The distortion can be minimised, but I have yet to definitively solve the problem, only achieving up to 1/2mm out of flat depending on where the hoop has bent.

Pedal action:
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Pedal casting dressed & nylon inserts reamed so that the pedal fulcrum spacer can be gripped firmly between the pedal arms without inhibiting the pedal movement.
The fork pressing cleaned, lubricated and the fork casting dressed to ensure squeak free smooth operation.
The adjustment screw barrel nut tapped, de-burred and lubricated to ensure easy adjustment and smooth movement.
All three elements allow the pedal to operate without resistance; the pedal return pressure is provided by one spring inside the clutch mechanism.

Pedal mechanism:
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All the work here is aimed at making the pedal operation smooth and resistance free, and to enable the whole assembly to be stiffened. Therefore decreasing friction in the vertical operating movement whilst minimising horizontal play.
My aim is to improve feeling whilst playing, assist the function of the clutch mechanism and facilitate greater accuracy in instrument set up which in turn improves quality of tone.

Chassis
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New aluminium shoes have been welded onto the foot of the base casting, and now the chassis are ready to be cleaned and painted. As the drums are moved, the casting wears down which lowers the front to the point where the pedal mechanism fouls the floor. Screwing on a plastic pad is a temporary fix, but the problem is that the force applied to the pad is shear, and that is the weakest aspect of a screw. Once the screw has snapped, your left with removing hard steel from soft aluminium.
After the chassis have been worked on, and the set up done, everything is ready for reassembly.
Job complete
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