Open hole pad grommets

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HMannfan
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Open hole pad grommets

Post by HMannfan »

What method or tool do you use when reinserting the metal grommets (retaining ring) on open hole keys? I have seen several different tools offered for this purpose. Do you ever find the need to vary the depth of insertion? Or do you generally find that you insert them fully? Is any lubricant used between the grommet and the wall of the key hole?

Removal of these grommets from my old Selmer flute varied from difficult to very difficult. I noticed that there was a lot of tarnish on the top edge of the tone hole and on the grommets down to where they made contact with the tone hole and a very slight amount on parts of their mating surfaces. Could this contribute to the difficulty in removing them (like they were stuck together at that point)? They were certainly in there tighter than I had anticipated. Is this an area that can cause a leak?

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pied_piper
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Re: Open hole pad grommets

Post by pied_piper »

Flute grommet insertion depth can vary between flute brands and the type of pad being used. However, on any given flute, the grommets should all be consistently inserted to same depth. Otherwise, some pads may be over compressed and others may not be secure enough. Experienced technicians can often do this consistently without a special tool, but less experienced techs may find a tool helpful in achieving greater consistency. The J.L. Smith grommet tool is pretty good for that purpose because it offers an adjustment set screw stop to provide that greater consistency.

http://www.jlsmithco.com/FLUTE-TOOLS/FL ... MET-SETTER
"Never give a flute player a screwdriver."
--anonymous--

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JButky
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Re: Open hole pad grommets

Post by JButky »

pied_piper wrote:the grommets should all be consistently inserted to same depth.
And that is inserted fully.. No other option is really acceptable.

The reasons as to why and how you should handle it are numerous. But that tool in the link is a hedge for people who don't want to do the job correctly and just mess with how far they put the grommet on without fixing the other issues to make it work properly.

...not that I have a really strong opinion about it... :wink:
Joe B

HMannfan
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Re: Open hole pad grommets

Post by HMannfan »

JButky: Don't hold back! Tell me what you Really think! :D

That is the answer I was expecting to hear. That is the answer that makes most sense to me. Thanks.

But, if you would, answer my other question please: What tool do YOU use to reinsert them? They don't seem to be too fragile, but just driving them in with a hammer and punch doesn't sound prudent. I have seen special pliers and the Eldred Spell 'Widget.' I suppose either one would be fine.

pied_piper: Thank you for your opinion as well. I have seen the tool you gave the link for and considered its purchase, but had reservations. It is a 3 month backorder item at this time.

mirwa
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Re: Open hole pad grommets

Post by mirwa »

I've got to admit, I looked at the link pied posted earlier today and was dubious when I read on Jeff's website the write up.

Out of respect to Jeff, I didn't post a reply. However I do concur with joe,

Steve

mirwa
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Re: Open hole pad grommets

Post by mirwa »

I insert the grommets back in with my thumb on plastic units, and the metal open tone hole ones I use the back of a pad slick to press it home after resizing it.

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JButky
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Re: Open hole pad grommets

Post by JButky »

HMannfan wrote: But, if you would, answer my other question please: What tool do YOU use to reinsert them?
I have a simple tool I made myself. A piece of ABS plastic rod turned in a lathe. I'll take a picture later..
Joe B

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JButky
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Re: Open hole pad grommets

Post by JButky »

Here's my simple grommet pusher...
Attachments
Grommet pusher
Grommet pusher
P11-06-13_11-39.jpg (59.79 KiB) Viewed 16039 times
Joe B

HMannfan
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Re: Open hole pad grommets

Post by HMannfan »

Thank all of you for your replies.

Joe, thanks for the picture. I like that. Simple, functional, cheap.

I'm going to assume that after I get the key chimney and grommets all cleaned up nicely that both reinsertion and removal during pad adjustments will go more smoothly and easily than their initial removal.

Mark

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JButky
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Re: Open hole pad grommets

Post by JButky »

HMannfan wrote:
I'm going to assume that after I get the key chimney and grommets all cleaned up nicely that both reinsertion and removal during pad adjustments will go more smoothly and easily than their initial removal.
Not necessarily. The grommet should be tight. ( you develop a feel for what is right) . However, repeated removal when working on padding can loosen the grommet from rocking back and forth for removal. You do need to shrink them back down if that happens. A collet of the correct size for the grommet is needed.
Joe B

HMannfan
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Re: Open hole pad grommets

Post by HMannfan »

Joe:

Would a tool similar to the flute grommet plate #227075 sold by J.L. Smith, accomplish the task?

http://www.jlsmithco.com/FLUTE-TOOLS

I would need to make a custom collet for this particular instrument. The grommets I removed measure approximately 8.55mm inside. The chimney measures about 8.57mm. A .02mm interference fit? Does that sound right to you?

Do you make your own tools for this purpose? How do you use a collet? I know, I need a class in metalworking. But if you could give me a simple explanation of what the process would be, I'd be very grateful.

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JButky
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Re: Open hole pad grommets

Post by JButky »

Yes, that will work. Not as handy as a P60 set from Ferree's but a lot less to get the job done. I do use the rotor bearing tool for flute grommets. It's perfect for that.
Joe B

HMannfan
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Re: Open hole pad grommets

Post by HMannfan »

Joe B:

Thank you for your response. ZOOM (over my head). I'll try to figure it out.

I'm a retired carpenter. I spent 35 years learning how to manipulate wood in every way possible using every woodworking tool you could imagine. I can do anything with wood. I have thousands of dollars worth of power and hand tools in my garage for carpentry and woodworking. I know very little (read: nothing) about metal working.

Using the J.L. Smith tool, are the grommets simply pressed into the hole in the tool corresponding to a diameter smaller than the key chimney forcing the diameter of the grommet to be reduced slightly, and when it is pressed onto the key chimney it flexes (expands) to fit the chimney and grab it tightly?

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JButky
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Re: Open hole pad grommets

Post by JButky »

HMannfan wrote: I can do anything with wood.
well maybe not anything. How's that Wooden Metal Forge? :wink:

Using the J.L. Smith tool, are the grommets simply pressed into the hole in the tool corresponding to a diameter smaller than the key chimney forcing the diameter of the grommet to be reduced slightly, and when it is pressed onto the key chimney it flexes (expands) to fit the chimney and grab it tightly?
Yes basically, forcing the grommet into one of the holes shrinks it so that it fits tight on the chimney.

The shrinking die is the same but variable. Think of a split ring with a mechanical closer to make the hole smaller. You don't need many holes, just the one collet that is size adjustable.

The effect is the same with either tool.
Joe B

HMannfan
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Re: Open hole pad grommets

Post by HMannfan »

Have you ever heard of Ironwood? :D

O.K. That helps to clear up the picture better. Thanks Joe B. I'm looking into replacing them with delron washers if I can get the proper size.

Mark

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