Carbon Fiber Shafts

[otlew]

I have been considering making an upper straight shaft of carbon fiber tubing. The upper shaft tube on mine GT is about 33" but I will round it to 36" for calculating.

7/8 x .065 wall 6061 Temper 6 weighs .1945 lb per foot x 3'= .5835 lbs

Carbon fiber tubing unidirectional weighs .062 lb per foot x 3' = .1860 lbs

Making the Aluminum tubing a little over 3 times heavier than the Carbon Fiber tubing. At about $80 for 5' shipped that is a lot to pay however. There might be other technical issues like drilling and cam locks. I hip or chest mount sometimes but still even then the lighter the better.

Comments?

 

[erikk]

Is saving a few ounces such a big deal? if so WHY?

 

[otlew]

If you consider that shaving a few ounces here and few there might soon add up to a 25% weight savings it could be, my GT all shaft mounted weighs 4-1/2 lbs (includes meter).

My Omega 8000 weighs 2 lbs 14 oz. and it feels a lot lighter, for two reasons, weight and ergonomics. Both which are found to be lacking on the Minelab Detectors, period. According to Dave Johnson the Omega designer, this was the first detector ever to be designed with ergonomics as a forethought and not hindsight. Too bad the Omega is not the machine that the Sovereign is, it is an all day effortless machine to me.

Carbon fiber polymer reinforced does not suffer from corrosion as does metal, well remain pristine unless you severely abuse it and is many times stronger than aluminum, and stiffer as well, depending on strand orientation.

There is an old saying "give a tough job to laziest the person", he will soon find an easier way, the hard worker will do it the way he was taught until retirement.

I may that lazy person, just looking for an easier way

Is saving a few ounces such a big deal? if so WHY?

 

[plugger]

n/t

 

[Critterhunter]

I've thought about going carbon too. The way I look at it every little bit helps. I've saved almost a pound and a half off my GT using a custom shaft and lipo battery. There are a few companies who make and sell carbon fiber shafts at VERY low prices that are popular in the RC plane community. We use them for things like strenghtening wings and such. I can't remember the company name off hand but it might be Midwest who is one of the cheap ones. For instance, they sell carbon tubes for a buck a piece that would cost $5 or more anywhere else. These are tubes about the diameter of a pencil. You might go on RCGroups and search for cheap carbon tubes or post a message asking where to get cheap carbon. I mainly get my small diameter carbon for my planes now from Walmart when they are on sale. Just picked up some carbon arrow shafts for $2.50 a piece there. Not as cheap as I could tubes online, but worth the "want it now" factor and saving shipping.

I've also thought about replacing the aluminum bike end bar I'm using for a grip with a carbon fiber one as they do sell them for bikes. Problem is the local stores want an arm and a leg for them. Still, I'm very happy with all the weight I've saved thus far. My GT never tires me out now and feels as light or lighter than my Whites. In stock configuration after about three hours my shoulder would start to hurt. You can see the mods in the "Lightweight GT" thread on here.

Drilling carbon won't be an issue but you need to seal the edges of the holes with crazy/super glue (CA) or something to prevent the carbon from running. There is a slight chance it will run or rip much like cloth otherwise.

If you are trying to save weight the biggest two items are replacing the arm cup with a Whites heavy duty one and replacing the battery with a lipo. The shaft would be next and using a carbon fiber Whites tall man rod and the aluminum inner tube from an Unger extending window cleaning pole (home improvement stores) will save you more weight.

 

[erikk]

If you consider that shaving a few ounces here and few there might soon add up to a 25% weight savings it could be, my GT all shaft mounted weighs 4-1/2 lbs (includes meter).

My Omega 8000 weighs 2 lbs 14 oz. and it feels a lot lighter, for two reasons, weight and ergonomics. Both which are found to be lacking on the Minelab Detectors, period. According to Dave Johnson the Omega designer, this was the first detector ever to be designed with ergonomics as a forethought and not hindsight. Too bad the Omega is not the machine that the Sovereign is, it is an all day effortless machine to me.

Carbon fiber polymer reinforced does not suffer from corrosion as does metal, well remain pristine unless you severely abuse it and is many times stronger than aluminum, and stiffer as well, depending on strand orientation.

There is an old saying "give a tough job to laziest the person", he will soon find an easier way, the hard worker will do it the way he was taught until retirement.

I may that lazy person, just looking for an easier way

Is saving a few ounces such a big deal? if so WHY?

Well since I wont consider myself retired until I am only hunting 2-3 days a week for 3-4 hours I guess I will continue to swing my Excal's with the aluminum straight shaft and WOT coil's & IMHO it is pretty easy as it is so if it "ain't broke, don't fix it" I also like big scoops

 

[otlew]

Well maybe I just like to tinker too much. As far as I am concerned lighter just sounds better.

 

[otlew]

n/t

Thanks Plugger, you should know if anyone does.

 

[synthnut]

If the Minelab lower rod is the same diameter as the Whites lower rod , the .065 wall is PERFECT for the upper rod ....I just put together 2 setups and at the advise of erikk , I ordered the .065 wall 7/8 Aluminum tubing from Aircraft Spruce for my upper rod, and used the Whites Tall Man lower rod assembly ....Fit like a glove .....drill out your holes for your spring latches , and you're good to go .....Nice snug fit with NO SLOP !!......Jim


OK , here's the deal !!...I just got my Minelab lower rods that came with my Sovereign .....They fit like a glove too !!!.... I was skeptical at first too , but Erikk has built a few of these too ....I didin't want SLOP .....Tight is right !!!......Trust me , it works !!!....You can go with the larger diameter I.D. if you want , but I have always liked it snug !!!....It still slides with no issues at all ....Jim

 

[otlew]

Hey Jim,

I have to assume that the lower rods for the Minelab and Whites are in the neighborhood (mfg. tolerances) of 3/4" (.750) OD, which fits inside of a 7/8" (.875) upper aluminum tubing shaft. If I understand correctly you do not require a cam lock, just spring the clip with an interference fit. Correct?

 

[synthnut]

Yes, you read me loud and clear ...... The lower rod does NOT measure the full .75 as you indicate .....I thouught the same thing but the tollerences of the lower rods are not as close as one may think after borrowing a set of calipers from my buddy .... I tried 2 Minelab lower rods , and 2 Whites Tall Man lower rods in these Aircraft Spruce .065 wall sets of tubing ....I ordered 2 - 4ft lengths of tubing and will end up cutting them down to 3 1/2 ft .....It will make for a nice balance of weight with the control box further back , especially for bigger coils like the 12 x 15 SEF coil .... It also allows for a little more lower rod material down on the lower end of the rod for even more support .... Yes it's a little bit heavier, but the support is nice to have .....Your call on the length .... 3 ft should work out fine too !!......Jim

 

[erikk]

Yes, you read me loud and clear ...... The lower rod does NOT measure the full .75 as you indicate .....I thouught the same thing but the tollerences of the lower rods are not as close as one may think after borrowing a set of calipers from my buddy .... I tried 2 Minelab lower rods , and 2 Whites Tall Man lower rods in these Aircraft Spruce .065 wall sets of tubing ....I ordered 2 - 4ft lengths of tubing and will end up cutting them down to 3 1/2 ft .....It will make for a nice balance of weight with the control box further back , especially for bigger coils like the 12 x 15 SEF coil .... It also allows for a little more lower rod material down on the lower end of the rod for even more support .... Yes it's a little bit heavier, but the support is nice to have .....Your call on the length .... 3 ft should work out fine too !!......Jim

You might find 3 ft a bit short depending on your height. I would rather get the 4 ft and cut it back a bit-easier than trying to stretch the 3

 

[otlew]

Yes, I agree errik, better too much rope than not enough as the saying goes.

Jim, I measured the lower Minelab shaft at two places. Near the coil it read .7460", on the lower shaft that enters upper shaft it read .7445. I may be seeing wear and/or differences in manufacturing runs at Minelab's supplier. An under-tolerance range of .0055 to .004" would seem to be fairly tight.

Jim I almost forgot to ask, what is the total length of the Tall Man lower shaft above the coil mount to the other end? Also will the rod end fit the Minelab Tornado or will it require shimming?

 

[synthnut]

You will more than likely be finding one hole in your upper rod that will be the length that you want and you will probably not be taking it apart much ......Why would you want a rod setup that flops around ? ....... You can get any I.D. you want , but I'm telling you , just like Erikk told me .....If you want more slop , get a bigger I.D. ....If you want a nice tight fit , and STILL be able to adjust your rod, get the right size and in this case it's the .065 wall tubing , but ONLY from Aircraft Spruce ....They have GREAT material and inexpensive too !!..... They ship it in hard cardboard triangular boxes that really protects the tubing ...... You want loose ? ....Buy loose ....You want tight where you need not extra clamps, and spring clips do the job, then buy tight and buy right !!......your choice ......I went thru the same thing you're going thru ....I just took Erikks word for it , and went for it ......He was SPOT ON !!!......

From the top of the coil mount to the end of the Tall Man rod is 32 inches ...... I bought my Tall Man rods from KellyCo and also bought the coil mounting kit which comes with the rubber mounts and the plastic bolt and nut .... I'm swinging a 10 x 12 SEF with no problems ...... I'm pretty sure the Tornado and even the E Trac coils are all built with the same spread on the mount .....One size fits all .....Jim

 

[plugger]

n/t

 

[plugger]

n/t

 

[synthnut]

plugger
I may be wrong , but if the fit were tighter , and there was no room for a bunch of crap to go up the rod , that the rod would stay relatively clean if washed off after a hunt ..... With the Tall Man lower rod , your spring clip is pretty high up in the top rod section , so there's not too much of a chance of that getting gunked up ...... ....Again, I could be wrong ....I know that I have had issues with loose fitting rods .....Maybe this will be the cure .....???......Jim

Erikk,
You have a few of these rod setups that are pretty tight .....Do you have any issues with sticking or problematic rods ? ......Jim

 

[otlew]

Jim I almost forgot to ask, what is the total length of the Tall Man lower shaft above the coil mount to the other end? Also will the rod end fit the Minelab Tornado or will it require shimming?

 

[synthnut]

Otlew
Go back a couple of spaces ...I already answered you ........

 

[GraveDiggerMax-VaBch-Va]

called anderson

gave them arm cup to hand grip length..............hand grip to end where coil bolts on...........used my best alum. shaft for measurements............done deal.....ALL ONE PIECE

no moving parts, no flex..........hard to beat............the arm cup or hand grip did come with 2 adjustment holes.........i forget which one now.

super light, super strong, the best shaft i have used in the big surfzone.

I am going to order yet another one in feb. or march for my garrett at pro
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