TDI Pro Coil Replacement?

[cjc]

Can anyone suggest a Coilek or other waterproof product to replace the stock coil on a TDI Pro?
Best Regards clive

[TowySalmon]

From what I have read, Coiltek coils are water resistant only, not waterproof. Even damp grass may cause issues and I would certainly not use one in the rain or on beaches where there may be lying water. Best suited to gold fields in baking temperatures?
I have several TDIs and am currently looking for suitable coils for beach use.

[cjc]

From what I have read, Coiltek coils are water resistant only, not waterproof. Even damp grass may cause issues and I would certainly not use one in the rain or on beaches where there may be lying water. Best suited to gold fields in baking temperatures?
I have several TDIs and am currently looking for suitable coils for beach use.

Carl had made a recommendaton to me a few years back was hoping he might answer here. I disagree--have used the 15" WOT and others in water for years.
cjc

[Carl-NC]

I have very little experience with aftermarket PI coils. I have a WOT but never tried it in the water, and have no idea which aftermarket coils are truly waterproof.

[cjc]

Thanks kindly for your reply, Carl. You had suggested a vialble coil for the TDI pro a few years back. Can you please refresh my memory as to which one it was? The W/P part can be figured out from there.
regards
clive

[Carl-NC]

Sorry, I can't remember.

[cjc]

It was a 10" Coiltech. Thanks anyhow--could always search the Serious Detecting site some of them come up when you search TDI. Hate to have such a superb detector sitting fallow...Like it more than the AQ as it gets big 22K.
Regards
clive

[dfbowers]

Clive. Build your own coils. They are about the easiest coils to make assuming you can find the right size shell.
The TDI is fairly forgiving.
Don.

[detectormods]

I would use nugget finder coils as my experience with them (over 30 years) is that the production techniques over the time have greatly improved that the coils do not suck in water, I have had both original Minelab and coiltek coils become water damaged, and this is evident when the coils become unstable or just do not work, the biggest problem is the graphite painted cardboard used for the faraday shield, if water gets in the paper crinkles up so it is easy to tell when you get forced to pull the coils apart, nugget finder paint the poly foam core and this adds to far better long term stability. To be 100% sure the coils won’t suck in water just put silicone around the join of the two halves of the shell, or even add a one way plastic valve or a long rubber tube with sealed end rising up from the coil so atmospheric pressure changes just effects the rubber like a balloon as not to create a huge pressure differential in the coil housing as even a pin hole will draw in water.

[cjc]

Clive. Build your own coils. They are about the easiest coils to make assuming you can find the right size shell.
The TDI is fairly forgiving.
Don.

Thanks--an interesting idea.
cjc

[cjc]

I would use nugget finder coils as my experience with them (over 30 years) is that the production techniques over the time have greatly improved that the coils do not suck in water, I have had both original Minelab and coiltek coils become water damaged, and this is evident when the coils become unstable or just do not work, the biggest problem is the graphite painted cardboard used for the faraday shield, if water gets in the paper crinkles up so it is easy to tell when you get forced to pull the coils apart, nugget finder paint the poly foam core and this adds to far better long term stability. To be 100% sure the coils won’t suck in water just put silicone around the join of the two halves of the shell, or even add a one way plastic valve or a long rubber tube with sealed end rising up from the coil so atmospheric pressure changes just effects the rubber like a balloon as not to create a huge pressure differential in the coil housing as even a pin hole will draw in water.

Good advice--especially with the Dual Field type coils. Even Bill Lahr hates them and has suggested that I reinfoce t he hardware.
cjc

[Aureous]

The 'All Terrain' coils that Coiltek made were the UFO and Platypus. They work terrific on the TDI models. The UFO ones were 17x11 and 24x12, both mono only. The Platypus were only 12x8 in both DD and Mono versions. These are the ONLY ones built waterproof.

[cjc]

The 'All Terrain' coils that Coiltek made were the UFO and Platypus. They work terrific on the TDI models. The UFO ones were 17x11 and 24x12, both mono only. The Platypus were only 12x8 in both DD and Mono versions. These are the ONLY ones built waterproof.

Thanks kindly for your reply, Aureous. I know those UFO's are very big-- too much drag for an old fellow but the Platypus sounds promising.
Best Regards
clive

[cjc]

Does anyone have an opionion on these Detech models?
https://detech-metaldetectors.ro/en/...-sd-gp-series/
https://detech-metaldetectors.ro/en/...ab-gpx-series/

cjc

[Aureous]

Clive, I suspect both of those Detech coils are not waterproof, just water resistant. If the coil in question isn't epoxy-filled, it aint meant for water use. It will be bouyant and any pinprick of air gap will suck in water. The Coiltek 17x11 UFO is a good one for beach detectorists, as is the 12x8 Platypus.