Question Cheap method to check balanced rig/trim weights?

[Morlan]

Just wondering how you all do a balanced rig check economically? I’ve calculated my weight requirement using the Optimal Buoyancy xls and it recommended for me to use 20 lbs. of lead.

So should I buy two sets of 1, 2, 3, and 4 lbs. of lead weights (totaling 20 lbs.) and play with combinations to get a good trim? Will these fit when combined together versus as a single weight; are the weight sizes linear? Any recommendations on weight manufacturers/sources?

Or is there some other clever, cheap alternative and doing some experimenting before buying the determined final lead diving weights?

Thanks in advance; hopefully this isn’t a dumb question.

 

[Jacob BV]

If you can I would borrow from friends, a club, or a centre before buying so you can try. You will be able to get the weight correct in one dive, getting the trim right can take more trial and error. Also worst case lead doesn't really lose its value much 2nd hand so you can just sell it on.

 

[johndiver999]

If you want some "soft" lead in bags of various sizes, send me a pm and we can probably figure something out for a good price. I have a bunch in the garage that has accumulated and I don't use it. All in good shape. Probably like 50% of retail - whatever that is?

 

[inquis]

I’ve calculated my weight requirement using the Optimal Buoyancy xls

Great tool. Have you measured your wetsuit buoyancy? That's the largest uncertainty in the calculations.

As for the trim, I suggest borrowing an assortment of lead from your local shop. Ideally they also have a pool to use.

 

[Morlan]

Great tool. Have you measured your wetsuit buoyancy? That's the largest uncertainty in the calculations.

As for the trim, I suggest borrowing an assortment of lead from your local shop. Ideally they also have a pool to use.

I’ve done the personal buoyancy measurement using the water bottles but I haven’t done the same in the wetsuit yet.

I’ll probably need the weights to do that too since the XLS estimates my full 7mm (wetsuit, hood, gloves, booties) to be 33.6 lbs. positively buoyant! I have a Bare Reactive 7mm wetsuit so I used New_Soft as the wetsuit type; not sure if that’s correct.

 

[inquis]

My Bare Reactive XXL measured at 16 lbs. Hood and boots almost negligible at less than 1/2 lb combined.

(I used a luggage scale to measure the suit in a mesh bag with enough weight to sink it in a hot tub. Then measured the same bundle without the suit. Difference was the surface buoyancy of the suit.)

Have also directly measured the other components buoyancies (tanks, rig, fins, etc.) Negative ones are easy.

 

[Morlan]

My Bare Reactive XXL measured at 16 lbs. Hood and boots almost negligible at less than 1/2 lb combined.

(I used a luggage scale to measure the suit in a mesh bag with enough weight to sink it in a hot tub. Then measured the same bundle without the suit. Difference was the surface buoyancy of the suit.)

Have also directly measured the other components buoyancies (tanks, rig, fins, etc.) Negative ones are easy.

That sounds a lot better than repeating the pool exercise with weights.

Were the Quick Results recommendations accurate after entering the correct personal and wetsuit buoyancies?

 

[inquis]

Were the Quick Results recommendations accurate after entering the correct personal and wetsuit buoyancies?

Yes, it's just math at that point, something a spreadsheet excels at. (Haha, see what I did there. )

 

[Morlan]

Yes, it's just math at that point, something a spreadsheet excels at. (Haha, see what I did there. )

Excel-lent! Thanks again!

 

[Akimbo]

I’ve calculated my weight requirement using the Optimal Buoyancy xls and it recommended for me to use 20 lbs. of lead.

Here is a link in case any readers have not seen @rsingler's spreadsheet:

Info - Optimal Buoyancy Computer

The Optimal Buoyancy Computer A tool to help nail buoyancy and improve safety, before you splash 1) How much lead should I carry with my new wetsuit? 2) How big a wing should I buy? 3) Will my BCD support my lead, both at the surface and when my wetsuit is compressed at depth? 4) Will my BCD...

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