P790 weight adjustment w/ toe screw

WARNING: This is basically irreversible and surely violates any warranty your club might have. Its also a pain in the butt. ?

(Pics below)

If you want to make small to moderate adjustments to the swing weight of your P790 iron, replacing the stock aluminum screw in the toe with something heavier and slightly longer is a pretty clean option that I have not seen anyone talk about (probably because of the aforementioned PITA). The stock threading in the head is 1/4-20 and 1/2" deep/long. A black oxide or stainless screw that size weighs 2g, and increases by about 1g per 1/4". If you were able to get Tungsten set screws you could obviously add even more weight for the same size. The screw will start to meet resistance once you pass the threading in the head which is useful for locking the screw in place (in the absence of or addition to any thread lock you want to use), but it will start flattening the threads of the screw, so be mindful if you need to take it in and out many times. Ideally you would use lead tape to find the weight you want and simply buy the correct size/weight screw to replace it just the one time, but you can still remove them quite a few times before there is any real issue in getting them to seat super snug. This is also a moot point if you plan on using Loctite or similar.

The pain is in removing the original screw. It is soft aluminum and weighs practically nothing, but is secured with some sort of thread lock as usual. Even with heat the head will still strip almost immediately. It is extremely easy to drill out though, but the leftover aluminum/thread lock stuck in the threads will need to removed manually. Once that is done though, you have a nice clean port for several lengths of screw. Anything longer than the 1/2" stock screw will start to push on the Speedfoam in the head, but its spongy so that doesn't really matter. You can make a little pocket n the foam for longer screws to rest in if that bothers you. You could also hypothetically remove the foam through this hole and have hotmelt applied instead, but I haven't gone that far and i'm not sure how much that would change the feel.

Using this replacement screw method you should be able to get up to 8g pretty easily if you need that much, more if you use longer set screws longer than 2" or made of Tungsten, but I don't want to recommend anything too long that leaves too much floating out in the middle of the head.

Nice write up and pics. I was just starting to dry fit a 790 UDI and my MOI is a bit low vs where I want it, so now this is another option to consider...I need to locate some tungsten screws!

Or you could spend about 5 seconds and about .25 cents and put a piece of lead tape on the back.

Shoot, I wish I had thought of that! ?/sarcasm

Not everyone wants lead tape on the back of their clubs, especially the amount it would take to build up 6g+, and ESPECIALLY on driving irons where you can see the back of the club from address, and this the lead tape you stacked up there.

So just to be clear. What’s the idea of putting more weight at the toe like that. Will it help someone with a fade or a draw. Thanks. 

19 hours ago, Jimmywebster said:

So just to be clear. What’s the idea of putting more weight at the toe like that. Will it help someone with a fade or a draw. Thanks. 

In theory it would make it easier to fade, but this much weight is not enough to make any noticeable difference. This is mainly for adjusting swingweight.

On 1/28/2024 at 9:34 PM, Jimmywebster said:

So just to be clear. What’s the idea of putting more weight at the toe like that. Will it help someone with a fade or a draw. Thanks. 

5 hours ago, spinnywedge said:

In theory it would make it easier to fade, but this much weight is not enough to make any noticeable difference. This is mainly for adjusting swingweight.

Yeah definitely not something meant for shot shaping, purely just a way to add a few more grams without using lead tape. 

Sometimes clubs need some lead tape on the toe they just do.