Rackets with hollow construction

I was cleaning up an old HEAD Club Pro racket, where the original grommets are all chipped off and turning to garbage. As I was removing them, some small pieces dropped INTO the hollow racket body itself. I then spent more than half an hour chasing those little pieces and forcing them to drop out of the grommet holes. However the question is when did HEAD stop making hollow rackets, or even today's rackets are still with a hollow core?

A side note, as I was using a screw driver cleaning the grommets, I accidentally chipped off a small piece of paint twisted, and I noticed it is clear that the Club Pro has high % of fiberglass construction, because the material under the paint looks as if it is semi-transparent glass, not like black graphite materials.

MichaelChang said:

I was cleaning up an old HEAD Club Pro racket, where the original grommets are all chipped off and turning to garbage. As I was removing them, some small pieces dropped INTO the hollow racket body itself. I then spent more than half an hour chasing those little pieces and forcing them to drop out of the grommet holes. However the question is when did HEAD stop making hollow rackets, or even today's rackets are still with a hollow core?

A side note, as I was using a screw driver cleaning the grommets, I accidentally chipped off a small piece of paint twisted, and I noticed it is clear that the Club Pro has high % of fiberglass construction, because the material under the paint looks as if it is semi-transparent glass, not like black graphite materials.

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HEAD never has stopped manufacturing hollow constructed racquets. HEAD racquets are still hollow to this day.....

vsbabolat said:

HEAD never has stopped manufacturing hollow constructed racquets. HEAD racquets are still hollow to this day.....

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Thanks vsbabolat.
Is this true for the other racket brands? (wilson, prince, for example?)

I think so. In the 80's many frames had a foam core, but other than PK these days I'm not too sure who else makes a frame with any 'filler'.

Thanks galain. When you exclude PK you mean the particles PK put in like the 5g/7g etc stuff they add in there?

MichaelChang said:

Thanks vsbabolat.
Is this true for the other racket brands? (wilson, prince, for example?)

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Sure. Wilson has some foam filled racquets like the K6-1 Tour 90 and the KPro Staff 88. I am sure there are some others...
Prince used to have foam filled racquets like the Graphite, Boron, Graphite Comp.. I think when the CTS line came they went hollow. But as far as I know the Prince Graphite is still foam filled. All of Kneissl racquets were hollow and Fischer are hollow. Dunlop are hollow. I remember when someone I know years ago dissected a broken Rossignol F200 it was foam filled.

Technically all racquets are hollow. Some have a foam injected into them.

What are the pros and cons of hollow versus foam injected then?

the POG 4 stripe was foam filled but my POG made in USA 1 stripe is solid in laid graphite, no balloon animals, no clowns, no foam, no mimes!!!!

MichaelChang said:

Thanks galain. When you exclude PK you mean the particles PK put in like the 5g/7g etc stuff they add in there?

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Yep, that's what I was thinking, but big thank you to VSBab for expanding on my rather anaemic 'list'!

vsbabolat said:

Sure. Wilson has some foam filled racquets like the K6-1 Tour 90 and the KPro Staff 88. I am sure there are some others...
Prince used to have foam filled racquets like the Graphite, Boron, Graphite Comp.. I think when the CTS line came they went hollow. But as far as I know the Prince Graphite is still foam filled. All of Kneissl racquets were hollow and Fischer are hollow. Dunlop are hollow. I remember when someone I know years ago dissected a broken Rossignol F200 it was foam filled.

Technically all racquets are hollow. Some have a foam injected into them.

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Indeed, I seem to recall that some Prince dealers had a nifty little display item issued to them in the mid-80's that had a short segment of frame hoop cross-section (cut from real frames) from each of their line-up: Graphite, Comp, Pro, and Classic. The composites had foam cores, the aluminum rackets were hollow, of course...

virginia said:

What are the pros and cons of hollow versus foam injected then?

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Virginia, you'd need to wade through a treatise on acoustic tuning to really get into it. Suffice to say, air (as in a hollow frame) can be a means to absorb vibration (or modify it to a friendlier amplitude), as can synthetic foams of varying density.

However, these work in a complex relationship with the wall composition, thickness, and shape of the frame itself to achieve the desired compromise between weight, flex, feel, strength/durability requirements, and the nature of vibration shedding (as in a tuning fork) desired... moving targets all.

Some manufacturers seem to have been set up to use foam cores in their manufacturing (the Taiwanese and asians from the start and on through today) whilst the Austrians seem to have avoided it or thought it unnecessary. Hollow frames tend (with a few exceptions) to be larger/bulkier in cross section, whilst historically the foam-cored frames seemed a bit more svelte. One could generally conclude from this that the area required within the "tube" of the hollow composite frame for manufacturing requirements or for enough dampening effect by the air, that foam makes for better dampening within the envelope of a smaller space, and/or lends strength. The thinbeamed Head Prestige mids, for instance, are hollow with very small air spaces within the wispy beam cross-section, but are admittedly relatively fragile.

you are the man retro!

plasma, I checked my individual-grommets version POG 1 stripe. the one has half grommets chipped off so I can peek into the grommet holes to see if frame is hollow or not. It does seem non-hollow from a couple of angles. However I can not be sure if it is non-hollow below the throat to the handle area. I was told this racket's handle is a 2-piece structure so I suppose the area below throat to the top of the grip is small even if it is hollow.

plasma said:

the POG 4 stripe was foam filled but my POG made in USA 1 stripe is solid in laid graphite, no balloon animals, no clowns, no foam, no mimes!!!!

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Any samurais? :lol:

Vantage's are foam filled along with a number of Wilsons (as stated previously).
My Dunlop aerogels are hollow, you can see the nails going through the handle if you pop open the "trap door" on the buttcap. Not sure about my volkl and fischer frames as I haven't messed with their handles.