Custom/Light Weight GT Picture

[Critterhunter]

OK, with the final stock GT weight (rechargable pack, DigiSearch meter, stock 10" coil) of 5 pounds 8.31 oz and my light weight GT running 12x10, lipo, etc, along with the DigiSearch meter at 4 pounds 3.9 oz, that means I've saved a total of 20.41 oz or 1 pound 4.41 ounces. Just 3.59 oz short of 1 and 1/2 pounds! I'm pretty happy with that. Thanks again to everybody for weighing the stock GT and DigiSearch meter. Now I may see how much further I can push it with a carbon fiber upper shaft and shortening the coil cables. Should be able to drop it down another 4 to 8 ounces or so by doing that. That would put me at about 3 pounds 12 ounces or so. Lightest GT on the planet with the control box still mounted on the shaft.

 

[synthnut]

That' s a conciderable amount of weight you shaved off the Sovereign ...... You better move quickly to make that Carbon Fiber setup ....Kered is HOT on your trail making the lightest he can !!.... YOU CAN DO IT !!!.... Jim

 

[Critterhunter]

Here is where I got the aluminum for the upper shaft portion of my custom shaft. It's an Unger professional window cleaning pole and can be had for $20 at Home Depot or probably Lowes. The picture shows a blue color but all the Ungers I've seen are green. Etore is blue, and I wouldn't use the Etore as they are heavier so the aluminum is probably a thicker grade. The inner extension pole is the one to use. It's the same diameter of the stock upper GT shaft but much lighter in weight being a lighter gauge, yet it's stiff as heck. Has to be to withstand extended weights of 10 feet using a mop head and other window cleaning tools.

The beauty of buying this to use the aluminum for the upper shaft is not just weight savings (use a Whites tall man carbon rod for the lower shaft), and not just that it's found at any local home improvement store, but also because you get an extra snap pin clip with it as that's how the top plastic green tool holder is held in place on the shaft. Cut off a section of the inner shaft to the desired length for your Sovereign (much shorter than stock if using a Whites Tall Man Rod), and you also will still have a slightly shorter but still extending window cleaning pole for around the house, changing light bulbs, dusting, painting, and other things. Much more value then buying some blank aluminum stock through mail order somewhere by the time you pay for shipping.

Interestingly enough, Unger also is selling a carbon fiber version of this pole, but they want way too much for it. I know of real cheaper sources for carbon via mail order should I decide to replace the upper shaft with carbon for maximum weight savings.

This grade aluminum is meant for constant outdoor use in the elements for years. My original Unger pole had about 15 years of use in the window cleaning trade and hasn't oxidized or fell apart on me. They may sell shorter versions of this pole cheaper but I haven't compared them to see if they are the same diameter as this one.

You do not need a cam lock. Just drill a hole completely through the aluminum for the snap pin's two heads to pop out of and it's going to be plenty stiff enough. From my experience Camlocks strip quick and don't do squat for rigidity of the shaft.



http://www.homedepot.com/Cleaning-Cleaning-Tools-Supplies/h_d1/N-5yc1vZ1xjvZbqqz/R-100200920/h_d2/ProductDisplay?langId=-1&storeId=10051&catalogId=10053

 

[TowySalmon]

What a fantastic read.
I am in the UK and have just ordered the lower long Whites shaft and arm cuff.
I have spent ages looking online for "Unger professional window cleaning pole" with 3 sections that goes to 10 feet so that can use the inner section as described, but I have no idea which particular model to order here in the UK.
It would be wonderful if someone could post a link or links to the required pole.

I have the bent shaft. To make up the straight shaft, what do I use as the handle/hand grip?
Thank you.

 

[Critterhunter]

The Unger pole only has two sections...the outter one and an inner pole that extends from it. The link above will take you to it.

You use what's called a bike end bar for a hand grip. Most any bicycle shop should carry them.

Good luck with your custom shaft.

 

[tiggar]

nice setup Critterhunter,

hh,
George

 

[deepdiger60]

Those are some nice lite machines i like the graphite rods i might get the lower one but as it stands now i can swing the coil with no problem , i cut off about 25 inches of coil wire i just dont need all that wire if iam hip mounting the unit the probe is balanced just right next week i will try the WOT 15 coil and see the overall weight HH Jim

 

[Critterhunter]

Just bumping this thread up as I've been asked about building a light weight GT and also about lipos. For more detailed lipo or Accucel 6 (great cheap computerized charger for many battery types) info do a search for lipo or accucel 6 and you'll find some threads. In one I cover extensively how to set up this charger for various batteries and such.

 

[Critterhunter]

So how's my custom light weight land rig been holding up? Well, just fine. In fact, probably at least half of my hunting over the past couple years since I built it has been hunting in the woods. Fighting brush, banging into trees, even fell down on the box/shaft a couple times here and there climbing up and down steep ridges and such. She's been used and abused and is holding up just great.

For water hunting though I use the stock shaft and would recommend any water hunting rig to be extra beefy like that. Either the stock shaft or one of Pluggers (found at Findmall Sponsors like Indian Nation) shafts or something. Really, for the hassle free aspect of it and a meter v-clip mount already found on top of the grip, his shafts are a great value and very well made from what I hear. Already has the box clip on the shaft too just like the v-clip on top of the grip, and you can even order models for older Sovereigns that used the V-clip to mount the box instead of the style of clip used on the Elite and GT. He sells shafts meant for water specific hunting too, as well as his great land rigs, for both the Sovereigns and the Excal. I bet his shafts are lighter than the stock Minelab hardware (nothing is as heavy as that!) but I wanted max weight savings, thus I didn't buy his shaft and did this thread building my own to max out every little ounce saved via various things.

By the way, there is a huge thread in the Modifications forum called "Sovereign GT Mods" that has further shaft customizing info from me and others. One person built an entire carbon fiber shaft for his GT to max out the weight savings on that. I would have done that myself but my upper shaft is a much lighter grade of aluminum than the stock upper shaft anyway, and with the longer Whites lower carbon fiber shaft I used I was able to cut down the length of the upper shaft much more than stock length to max out the weight savings there too.

I remember some excellent threads on custom shaft builds from people for their Sovereign or Excals. Sooner or later I'll get around to digging them up and post some links in the Excal and Sovereign accesseries stickys. People had some great ideas. Even things like using aluminum walking cains that already have an arm cup and grip on them like they were just meant for using with a metal detector. Also 3 or 4 piece break down aluminum walking canes too. I remember some mentioning you could often find these things for a couple bucks at places like the Salvation Army or Goodwill stores where they sell used stuff people cleaned out of their basement or garage. Very slick...

 

[Critterhunter]

Just wanted to link this thread to another one on related subjects of building a light weight shaft and doing the mods found in this thread like adapting the Minelab box clip to be used without the stock arm cup holding it to the shaft. Easy stuff. Somebody in this thread linked below is also talking about using a one piece carbon rod for his entire shaft if you want to shave the last few grams off a light weight build...

http://www.findmall.com/read.php?21,1774626

 

[Critterhunter]

Got this privately. Since it's a common question and not a sensitive topic figured I'd answer it here with the name stripped...

Hey Critter, is the Whites tall man rod(light weight) the same diameter as my bottom GT ROD? What's the weight difference? I'm thinking of putting one on my GT. Do you need spacer washers on the coil? Thanks for the reply.

I've been busy working on youtube videos, and just finished one (more like a pictorial) that I think should answer all your questions nicely for you and then some. Link below. It covers a bunch of light weight/custom shaft info and other mods, and some other unrelated topics (the 13" Ultimate, how I carry my digging tools, remote PP switch, etc). But up front...

Yes- the Whites tall man rod will fit the stock shaft just fine far as I know. Never checked but I know my upper lighter aluminum shaft is I think the same inner diameter as the Minelab upper shaft, and since the Whites rod fits in my lighter upper shaft nice and snug don't see why it wouldn't on the Minelab. You know, just to be safe, if you look probably on the last page of the Sovereign accessories sticky you'll find a thread noted for discussing the inner/outer diameters of the stock Minelab shafts. Check out White's website for the specs of the tall man lower rod and there you go, or if it ain't listed shoot Whites a PM and find out. I'm sure it's a dead match but just the same.

Far as the weight, the Whites tall man fiber rod is about twice the length yet much lighter than the stock heavy fiberglass lower shaft. Added perk- You can then cut down the length of your stock upper shaft to save more weight. But rather than modify the stock shaft in that way (always good to be able to go back to stock configuration for re-sale value), I'd shoot for even more weight savings by going to a lighter gauge aluminum for the upper shaft. You don't need the cam lock. Just drill the upper shaft so both snap pin adjustment heads pop out both sides. That's a good tip to take slop out of the stock shaft as well, as Minelab only drilled out the hole for only one head on the adjustment snap pin to pop out one side of the shaft. You wouldn't believe how good that snugs things up, so long as you only drill a hole just big enough for the head to pop out.

Back to the weight- As with all things, Minelab over engineered stuff and in the process added a lot of weight. Can't argue they don't build a solid machine, but at the cost of weight. The stock arm cup, for example, weighs 8.8 ounces (over half a pound). If you are picking up a Whites rod I'd pick up the arm cup while you are at it. The "heavy duty" Whites arm cup is only I think $10 and much lighter than the stock one. Good bit of weight savings there. I also had picked up two tall man rods. Makes coil swamping fast. Wish I had bought 3 now.

Far as the washers...You need four. A pair on each side of the Whites coil mount since it's not as wide as the Minelab coil mount. Pick'em up in the faucet repair section of home improvement stores. Glue them in pairs for easier install and then drill out the center hole of them to match the diameter of the *Minelab* nylon coil bolt. Easy as pie, and cheap. I think the Whites coil bolt hole is larger diameter. Not an issue. But I wouldn't switch to the Whites bolt size because if you drill out the mounting ears on your coils for it to fit that might weaken them. Just use the Minelab bolt which, which I'm pretty sure is smaller than the Whites from memory anyway. It works just fine even if the bolt hole on the Whites rod is bigger.

Beyond all that, here's my latest Youtube video- Many of these mods and others are covered in this pictorial, such as the remote PP switch, doing other easy/cheap mods to drop a bunch of weight on the GT without mucking with the control box (don't need to- it's fine and light as it is), and intended waterproofing mod for fast land/water conversion deeper than you can go out of the box chest mounted. With Kbron2000's great find- cheap/perfect size waterproof Plano box to throw your GT into for fast land to water hunting transistion so you can go neck deep like an Excal with no worries, I'm configuring it a bit different in how I carry it so no issues with it floating, dragging, or even risking a leak in the water. Fast easy water/land conversion, just like the GT is stock for land/water transisition. Also covered is how I carry my digging tools and various other more specific Sovereign info in this video, including a bit more on the 13" Ultimate coil. Primarily though it's about custom and light weight builds...

http://youtu.be/vvkeNKPYsgA

 

[Critterhunter]

Pics first, then weights...
[attachment 248632 inhand.jpg][attachment 248633 holder.jpg][attachment 248634 batteryinholder.jpg]

The stock re-chargeable 1000ma nimh Minelab pack is 9.8 oz.

The Alkaline holder using a 3 cell 750ma lipo weighed 5 oz!

That's a weight savings of almost half. One of many perks of lipo cells, as they are probably the lightest battery technology on the market these days that I'm aware of. One of the reasons they are so popular in RC electric planes

And I'm getting I think about the same run time as the stock 1000ma nimh pack even with the lower capacity of the lipo, because lipos hold their voltage very high until the very end of discharge, thus running into the low battery alarm later than nimhs with a somewhat higher capacity due to them dropping more steadily in voltage as they drain. I can at least get two long hunts out of the pack.

The math says on typical average Sovereign average amp draw of about 50ma, I should get about 15 hours of hunting time, but keep in mind lipos, just like nimhs, often hold higher capacity than the label says. I think off hand this lipo when charged holds closer to maybe 900ma of capacity. I'll never really paid much attention to it but it's been my experience with both lipos and nimhs when I noted that in the past, and I know for sure noting that this lipo is holding well above it's stated capacity. Either way, around 15 hours is fine with me, as that's typical of about two hunts for me or so, and so on the second hunt I just make sure I bring my second pack along should it bomb out by then and not on the third or fourth hunt or so.

If you are shooting for max run times and not max weight savings, easy enough to cram a 1500ma pack in there without issues, as I've seen Kered do it on his. You probably still will save weight over using 8AAs, and for sure over using the stock rechargeable nimh pack. I wanted max weight savings though, since lipos don't self-discharge, so I don't have to worry about re-charging packs if they've sat around for weeks or even months like I would with nimhs. There are low self-discharge nimhs on the market though. Some of which I hear are very good at maintaining a shelf charge, but still not quite as good as a lipo at it.

I'm going to have to wear a watch and time my hunts, freezing the timer during breaks when I have the machine off, so I can put an exact # on the run time. I'm very happy with it, and the lipo was so cheap ($7) that I bought a second one as a spare backup, which is much easier to carry in a shirt pocket than 8AAs of course, not to mention much lighter.

If somebody can weigh the alkaline holder with 8 non-rechargeable AAs in it, I'd appreaciate that, as I don't have any laying around to weigh myself in it to see the contrast in weight. I almost never use non-rechargeable AAs anymore. I either use nimhs, or I use those Energizer non-rechargeable lithium ion cells, as they last so much longer and are so much lighter than regular AAs. In whatever I can though, like my GT, it's lipos all the way. Can't remember the last time I ran AAs in it. If I want to use AAs again for some insane reason, I can easily move the little plug I soldered in out of the way and throw 8 in there. Just don't ever see a reason why I would want to though.

Oh, and here's a thread in the modifications forum on the subject of lipo feeding and care I wrote about it...

http://www.findmall.com/read.php?22,1762234,1774606#msg-1774606

 

[Critterhunter]

OK, with the final stock GT weight (rechargeable pack, DigiSearch meter, stock 10" coil) of 5 pounds 8.31 oz...

And my light weight GT with Digisearch meter, running 12x10, lipo and all other mods previously covered, etc, at 4 pounds 3.9 oz, that means I've saved a total of 20.41 oz or 1 pound 4.41 ounces. Just 3.59 oz short of 1 and 1/2 pounds! I'm pretty happy with that.

Since this post, I had ditched the stand I had built and instead am using two stick on rubber feet on the bottom of the control box because I like this setup better. Wasn't sure if I had done any other weight savings mods since this post either, so I figured I'd re-weigh my setup and see what the grand total in weight savings is. The above totals and the one below are without headphones...

Today I got 4 pounds 3.3 ounces, so that pushes the weight savings even further at a total savings of 1 pound 5.01 ounces, just 2.99 ounces short of 1 & 1/2 pounds of total weight savings over the stock straight shaft configuration of the GT as it comes from the factory with Digisearch meter and stock rechargeable pack on board.

Makes a huge difference by the end of a long hunt, and the center of gravity is also almost spot on right at the grip. If I try to balance the machine right around the grip, it dips forward putting the coil into natural hunting position. Wasn't shooting for perfect balance because weight was more of a concern for me, but looks like I got lucky in that respect too.

To push the weight savings even further, as a winter project I might shorten the coil and meter's cables, with the added bonus of less mess on the shaft and potential for EMI or inductance issues. I bet I can easily save that 2.99 ounces doing that to push it beyond the 1 & 1/2 pound weight savings mark.

About the only other thing I could do to save further weight is to replace the upper aluminum shaft with a carbon fiber one, or the hollow aluminum bike end bar grip with a carbon fiber one, which are cheap if you shop around.

I'm also curious if I can't scrounge yet a few more ounces in weight savings with the meter being used. Sometimes I ditch the Digisearch meter and use Ron's meter. I mostly use the Digisearch when beating up the woods because it's already seen a bunch of abuse from me, where as Ron's I want to baby and only pull out when I'm only planning to do open park hunting for a stretch of time.

So now I'm thinking...Wonder if Ron's meter is lighter than the Digisearch setup to push the weight down even further? I'm thinking it might be, since for one thing it doesn't have all that bulky thick long coil cable wrapped around the shaft and instead uses a much nicer/thinner wiring setup. That alone might shave me a few more ounces or so. I'm going to weigh his meter/wiring and then my Digisearch meter and see what the deal is on that, and when I get around to it I'll post the numbers.

PS- A few people recently asked me the weight savings of the White's tall man lower fiber rod compared to the stock Minelab fiberglass one, so today I weighed them both to refresh my memory. The Minelab weighs 4.7 ounces. The Whites weighs 4.0 ounces. Since the Whites tall man rod is much longer you can save further weight by cutting down the length of the upper shaft. I used lighter gauge aluminum tubing than the stock upper shaft from the inside extending section on an Unger window cleaning pole, and cut the length shorter than stock with just enough length to overlap the top and bottom rods a few inches or so to insure no slop.

All this stuff might seem like pennies and dimes, but I was always told if you take care of those the dollars will take care of themselves. Even a few grams or ounces saved here and there at the beginning of this project might have seemed pretty meaningless, but it ended up being well worth the effort with the total weight savings I've got so far.

 

[Critterhunter]

Today I decided to weigh the Minelab Digisearch 180 meter and Ron's meter to see how they compared. Ignore the white look around Ron's meter display, it's just glare from the lights.
[attachment 248937 IMG_2081.jpg]
The Digisearch meter was weighed with it's cable on the scale along with the Minelab V-Clip and pipe hanger I use to mount it on top of the bike end bar grip where I prefer it.

Ron's meter was weighed with it's included cable and the pipe hanger mount it comes with, which doesn't require one of of Minelabs V-clips. His meter can be mounted on the shaft, or you can mount it on top of a grip by bending the pipe hanger mount. I prefer it on the shaft since it's got a much higher profile than the Digisearch meter and can easily be seen past the grip. Some people even tilt a meter on the shaft a bit to the side so they can keep an eye on the meter and the coil at the same time as they work a target for better coil control trying to pull the best signal out of a difficult target.

The Digisearch meter was 9.3 oz in weight.

Ron's meter was 7.1 oz, and that's including the battery it runs on.

A savings of 2.2 ounces, which puts me at 4 pounds 1.1 ounces. 1 pound 7.21 ounces in total weight savings over the stock setup. That 1 & 1/2 pound mark is inching closer. Only .79 ounces shy. Plus I just want to see the total weight dip below 4 pounds and into the 3 pounds+ range. Shortening the coil cable should do both of those things for me.

PS- I also tested Ron's meter and the Digisearch on a few targets today to see if the scaling matched for both on stuff. I tested a quarter (180), a round tab (167), a military eagle tie clip (165), and a nickel (146). I'm happy to say all targets read exactly the same # on both meters, so Ron's meter will match the charts perfectly if using noise band 2.

I also wanted to pay attention to something with his meter that I hadn't before to see if it's the same deal as with the Digisearch meter. With the Digisearch meter when the machine resets (you'll hear the threshold reset) the meter will read -505 if it's adjusted properly to go 180 on a dime or quarter.

I made it a point today to take note of the negative number being displayed on Ron's meter to see if it does the same thing and it does read negative 505 too, so it's a handy tip to calibrate the meter if you don't have a coin handy.

I always do it that way so I don't need to mess with throwing a coin on the ground and picking it back up. I usually just thump the coil on the ground to get the machine to reset, and if it won't easily then I'll crank up the sensitivity a bit to make easier to do.

Either meter shouldn't need re-adjusted once set properly until you change coils, but I find the Digisearch meter always seems to need a tweak at the start of each hunt due to it's external POT control, where as Ron's is protected by an access hole on the back of the meter.

Sometimes either meter for me will read a bit off by a digit or two until the machine warms up for about 5 minutes, so I never mess with the calibration until I see that after about 5 minutes of being powered up the number is still a bit off on a coin, or when the machine has reset it's not reading negative 505. Never had to re-adjust Ron's meter though from one hunt to the other, unless I've changed coils.

 

[Ron from Michigan]

Critter,interesting comparison.Thanks Ron

 

[Critterhunter]

Yea, double post from another thread but hey thought this should go here too. Sorry.....

This should give you guys some better size perspective on just how tiny this 7.25" Tornado is.
[attachment 257957 IMG_2102.jpg]

Pretty darn small looking, eh? Still haven't used it yet. Too bitter cold out today for comfort. Just swung it around in the grass a few minutes without turning on the GT. EMI is real bad at this spot with a cluster of overhead power lines. Wouldn't be able to run it all out for a test spin without drastically lowering sensitivity. I just wanted to see how it felt. Man, that little bugger is effortless to swing around and feels like I'm using the end of a pool stick to scan the ground.

Excuse the dirty GT. Need to clean it up from some rather muddy hunts a few weeks back. Also need to put another velcro loop or two on the shaft to secure the coil cable better. I don't like any lose movement of the coil cable going up the shaft to prevent it being seen in the detection field and also any potential shorts developing over time with movement. Usually I also wrap the coil cable better behind the grip but just threw it together real quick for some pics.

One of the nice things about Ron's meter, unlike this Minelab Digisearch meter in the pics, is that you don't have all that extra bulky coil cable the meter comes with on the shaft. Ron's uses a thin short stereo cord, or you can plug an extension into it from Radio Shack to hip or chest mount the control box while still leaving the meter on the shaft. I only throw his meter on when I don't plan beating up the machine badly in the woods, since the stock meter has already saw a ton of punishment, so I figure Ron's should see more "gentle" days of use so I know I always have a second meter as a back up that's been babied in case this Digisearch meter ever bombs out on me. With Ron's I typically just mount it on the shaft past the grip since it stands tall and is easy to see, but by bending the pipe hanger mount it comes with you can also mount it on top of the grip.

Weighed my light weight land shaft rig here, minus my headphones, and this land rig is using a 3 cell lipo in the alkaline holder as I always do to drop extra weight plus no hassles with self discharge while the GT is in storage waiting for the next hunt like the stock nimh pack will do. Weights is 4 pounds 2.7 ounces. Even with the 12x10 on this rig it's a very light set up, but with the 8" Tornado it feels even more feather light on my arm/shoulder. Once this coil is out of warranty I'm ditching the coil cover and using spray on bed liner like I do all my coils, which will save me 1.8 ounces more weight and bring the total weight of the rig with the 8" Tornado on the shaft down to 4 pounds .9 (point nine) ounces. Getting closer to breaking that 4 pound barrier. Ron's meter is also about 2.2 ounces lighter than the Digisearch meter from memory, so that'll push the weight down into the 3 pound plus weight class when I slap it on the shaft with this little coil.

About the only other things I could do to drop more weight off my GT is shorten coil cables or replace the upper lighter gauge aluminum shaft I'm using with carbon fiber like the lower Whites tall man rod on this rig is, or also change the hollow aluminum bike end bar grip for a carbon fiber one of those as well. Not much more I can do to save a few more grams or ounces other than all that.

Think I'm going to like this little coil if the feel of it's sleekness is any indication as to how well it will sniper stuff out of trash. Also want to head to an old site and see how close to a fence I can get where I'm sure some silver lurks that the fence has protected for years from detectors.

 

[Critterhunter]

Just thought I'd throw this remark in this thread about what a fellow Minelab user had to say about the feel of my GT with the mods covered in this thread...

And after he swung the GT around for a few seconds the first words out of his mouth were "WOW, this thing is light!" When his SE is out of warranty he's got big plans to slim down it's weight. Can't wait to see what he comes up with. I've thrown him some links to some Explorer light weight mods people have done to give him some ideas, along with my pictorial video on the mods I did to lighten up the GT and make it more user friendly for me.

By the way, I wanted to try out the wireless headphones he was using so I threw them on my GT for a few minutes and either they've got issues working with the GT or the rain messed up my GT. I was about to leave anyway due to the rain but wanted to try them real quick. The audio was blanking out and the threshold had a fizzle sound to it like bacon frying in the far distance.

In a panic I pulled the battery from my GT and headed for the car. Not sure if it was the headphones or the rain, but I didn't want to risk it. I've got the GT drying out in a nice warm/dry place right now and won't dare to fire it up for for a while to see if it's got a problem. I got my GT wet badly last summer and the thing was completely screwed up, so I pulled the control box apart and let it air dry for a few days and it was fine. Couldn't find any evidence of water in the box to clean up or protect parts from future rust so I just left it at that.

Hoping that's the case this time as well, if the weird audio was even being caused by that yesterday and not just his headphones not working well with my GT. Got to stop taking these kinds of risks with the GT now. Use to hunt in a drizzle with it a lot in the past but now that the GT has been discontinued I got to take better care of her, as I'm afraid of how hard it might be to find a good price on a used one down the road.

They already were somewhat hard to find used and more often than not went for a premium price before the GT was canned, and I only expect used prices to go up even more as the new stock dries up. Minelab just dropped the price on a new one so that might hurt used prices a little bit, but once those new ones are gone I've seen price increases for a few other legendary machines used go up and become hard to find used and I fully expect that to happen with the GT.