Filling in undercut cavity - what material would you use?

[Noodler]

I was just thinking about an idea I have considered a few times; filling in the undercut cavity of a set of irons. Outside of debating the effect of doing this, what materials would be best suited to filling in the cavity?

 

I'm thinking that the material will need to be something that will flow fairly easily before drying, resist major shrinking, be temperature stable (irons in the sun can get hot), and have some adhesive qualities (to stay put). Of course the final density and weight of the material would be the characteristics that will impact the feel and play of the head.

 

The first idea I had was to use silicone. There also may be some types of adhesives that could work. I'm not really familiar with any off-the-shelf stuff like that. Is there anything at The Home Depot that might work?

 

I have searched the Internet and the forum and come up empty on this one. Either this is a really hair-brained idea or something that no one else has considered previously. Of course we have irons available now that use various polymers injected into the head, so that's why I was wondering if the "tinkerers" of the golf community had experimented with this idea.

[KRW59]

Liquid Nails Clear Seal all purpose sealant.( it's not silicone )

The word Polymar is used numerous times in the list of ingredients.

 

Years ago, before I invested in the real thing ,I used it like homelt

inside driver and fairway heads.

 

Once dry it will retain some flexibilty,and will adhere to most anything.

The rusty, oily butcher knife I tested it on still has a glob on it ten

years later that is soft enough to stick a finger nail into it, but surface

is not sticky . Tube says " 50 year durability "

 

When it is still in its gel / liquid state it will flow with heat from a

heat gun or hair dryer. It is messy sticky before drying, but easy to

clean up with mineral spirits or lighter fluid. If needed , I was able

to dissolve and get it out of driver heads with chlorinated brake cleaner.

 

Still have driver heads from 2007, that it has not come loose causing rattles.

[Carvallo Golf]

construction adhesive, my only concerns is the stuff sets pretty hard but it wont go anywhere. The liquid nails clear seal sounds good

[IsleOfMan]

I'd probably try a black RTV sealant. It's the go-to all-purpose sealant in the commercial aviation industry everywhere from cabin to areas that see extreme ambient cold (from exterior at altitude) or hot (near engine and/or accessory components). The black color will also not yellow over time and UV exposure like most clear or white sealants will.

 

https://www.walmart.com/ip/Silicone-Rtv-Black-3oz/125082804

[KRW59]

Liquid Nails Clear Seal all purpose sealant...5.5 fluid onces...$2.77

Permanent flexibility, stays crystal clear , will not yellow...

10 year track record of performing well in golf related application.

 

My secret hot melt alternative , has now been shared with the Wrx'ers

[JCAG]

OP

 

Why do you want to do this? You would need quite a bit of weight to change the center of gravity and this disregards what the added weight will do to club performance.

[Switter]

You may want to try J.B. Weld in either a two-part paste or the epoxy glue. They cure as hard as steel & both are sandable. The J.B. paste cures hard in 5 minutes.

[Noodler]

Thanks for all of your suggestions. I was not aware of most of this stuff. I'll be heading over to Home Depot to see what they have available. I'm going to test this out on a single club (either a Mizuno MP-53 or MX-25 6 iron). It will be interesting to see how much weight is added to the head and how it changes the feel of the strike.

[wkuo3]

My concern will be how easy to remove the filling in the future and if it could be removed completely. Unless you want to make this a permanent fixture on your golf club.

I would also ask the OEM service if this will void the implied warranty.

[Noodler]

No warranty concerns with this experiment.

 

For those wondering where I'm going with this...

 

I've been experimenting with high amounts of counterbalancing in irons. For quite some time I have used and advocated heavier shaft weight coupled with lighter heads, but of course a heavier shaft almost always means a stiffer shaft. For golfers that have a feel preference for their shaft (i.e. want to feel the loading), then you're kind of stuck on how to modify overall club weight and the resulting balance (MOI/MBI stuff) if you only use the typical components.

 

I needed heavier heads and a heavier grip. So I started experimenting with counterbalancing (like TourLock, Opti-Vibe) and realized that if you couple a heavy head, a light shaft, and significant counterweight at the butt end (>30g), then you would really increase the impact of the club balance (angular forces generated between the opposing ends). I also built the test clubs a bit longer than normal, built up the bottom half of the grips, and then gripped down when using the clubs. This is the same idea as when using a counterbalanced putter (which I use as my gamer). Gripping down keeps the counterweight higher above the hands, but gripping down on a longer club puts your grip position back to the normal level. Obviously you can't go too crazy with this since the butt end of the club needs to stay clear of your mid-section.

 

Anyhow, I'll start a new thread on this when I have more to say on the experiment. I've been encouraged by the effect on the club path tracking while having a lighter more flexible shaft that's easier to load. I need to see how this plays out with other golfers (friends/family) before I have more to say.

 

I know the Tour Lock folks have lots about this and Boccieri Heavy Irons are out there too. I'd like to see what's possible using a golfer's preferred components in a DIY approach.

[KRW59]

I knew there was a lot more to the story. Thanks Noodler.

 

 

[bobcat]

Gotta go with Dial for Men 'Speed Foam'...It sure works well for Taylormade!... :taunt:

 

 

 

[ws6]

I'd probably try a black RTV sealant. It's the go-to all-purpose sealant in the commercial aviation industry everywhere from cabin to areas that see extreme ambient cold (from exterior at altitude) or hot (near engine and/or accessory components). The black color will also not yellow over time and UV exposure like most clear or white sealants will.

 

https://www.walmart.com/ip/Silicone-Rtv-Black-3oz/125082804

 

X2 on rtv.