Hook Grasping

[Daniel Paulsen]

I have a question for hook users:

If you could pick only two difficult to grasp objects and have the ability to easily grasp them, what would they be?

Also please state what model of hook you are currently using. Check out www.hosmer.com if you are not sure what the model numbers are.

Any input is appreciated.

[Sean McHugh]

1. Motorcycle throttle
2. Motorcycle front brake lever
I currently use a Hosmer 555 (RBE amputation)

[Darryl]

Daniel,

This is a really loaded question,lol.

I find that most things are grasped with 70 percent efficiency. For me the hardest things are:

1.Nails

2.Nailsets

Hooks just aren't designed for these things.

I use the APRL VC. Left below elbow.

[Bill Taylor]

hey daniel,

i do a lot of carpentry, and my no. 7 hosmer "work" hook works really well for me. i've found that my regular no. 5 hook is about useless for nails tho. sometimes i need to change my wrist angle to get it into the right position [like nailing down flat on a floor.] i have a hosmer 3 position wrist which is really poorly designed. but it gets my hook into weird positions. for nailsets, i put the set in the little claws by the wrist , and put a rubber band around the points of my hook to increase the grip, and that works pretty well...or i put it out on the end in the nail holder and wrap fat rubber bands around it and the little knife holder to hold it steady. maybe you've tried all this before. if so, i'm sorry to bug you.

bill

[Bill Taylor]

oops, sorry my comment should have been directed to both daniel and darryl. and, i shoulda said that i'm lbe too.

bill

[Bill Taylor]

i guess the main thing for me is smooth, hard metal or glass things. i now use either a hosmer no. 5 or no. 7. depending on what i'n doing. i used to have a 5xa, but i was so paranoid about wearing out the rubber and bending it, that i re-sold it on ebay. that was somewhat better, but still not very good. it's easier, and a more solid grip to just grab the thing to my chest with my bare stump or if i have my pros on, back on my non-pros-covered upper arm.

[Darryl]

Bill,

That sounds like it works well for you. I found that the rubber finger pads on the APRL really hold hard, smooth items well. Especially with a tight grip. If my hook is wearing out then it makes it harder for me to stay locked on a nail set or chisel. But overall the function of the VC APRL is great for me doing all types of carpentry.

I would love to hear about other things you do, carpentry related or otherwise, with you hooks.
Thanks,
Darryl

[Wolf Schweitzer]

I use a voluntary opening Otto Bock hook with a spring (it's got two settings that cover the range).

Some things just don't work with a hook; grabbing a parking card in the car that is sitting there at a 90 degrees wrong angle can *not* be grabbed, not even with silicon fingers on the hook. Holding a freshly peeled onion while cutting it with a bluntish knife - can be done, but is difficult. Opening a glass of preserved food with a lid that's stuck, that is difficult - that's hard with two real hands. I hold it between arm/elbow and chest or between the feet, I use heat to expand the trapped air, I put the lid part of the jar into the ultrasound to try to loosen the lid a bit that way.

Holding a drill hammer, holding screws or so, not a problem in comparison. Small tinkering work, downhill in comparison, not worth mentioning. I also have some vices and clamps and that works.

[Bill Taylor]

hi darryl, or daniel....i'm still kinda confused as to which thread the 'reply to' is directed,

anyways, this is a response to darryl's input about carpentry....since i'm stuck with solid steel [hosmer 5 and 7], when i need to pick up delicate or hard stuff repeatedly, i have some old chem-lab rubber tubing i can squish down over the points of my hook, leaving the tubing ends a bit longer than the tips of my hook, so that the metal can't touch the thing i'm picking up....but that's a long process, so, not worth it for just holding a jar for a few seconds.

woodworking related stuff...i tried various things for pushing boards through my jointer. the rubber tube works well, but also i found that the very low tech and unprosthetic solution of pushing my stump into one of those non-slip socks, with the rubber traction surface down, works pretty well with better "feel" of the work [tho the vibrations coming through the board are a real phantom rush.]. the chisel holder of my no. 7 gives alot of angles to hold a chisel or nailset, and i put rubber bands over the hook tips to increase the grip. otherwise, i grip most of the tools at the places designed for the left hand with the no. 7 without modification. i really believe in not adapting the things in the world around me, lest i become unable to function in unmodified situations.

i do really small-scale electronics work, as well as high voltage transmitter work, and my work hook is good for that too, tho i use several types of clamps and vices to help hold things. my work hook is good for grasping a soldering gun or iron, though i can't hold the 2 position switch on the gun in the halfway, low heat position, so i just use a low-temp iron for that. i got a cable insulator put into the cable. it looks to be good for about 1000 volts, though i haven't tested it. i have used it for regular 120 volt house wiring and didn't get zapped...it's very handy in fact.

the problem with both the insulator and my hosmer 3 position wrist is flimsy design. these both impact my electronics work...the insulator's aluminum end caps wear through rubbing against the steel cable end balls inside, and the mechanical release "switch" on my wrist is a very thin casting in a place that's always getting hit when i carry big stuff, so it bends and breaks...and repair costs are astronomical, thus prohibitive.

let's see, another thing i do is gas brazing and welding. it's easy to hold the rod in my hook while working with the torch in my hand...just hafta be careful not to weld the hook to the work. there's some pictures of me working [amongst much other stuff] on our project blogsite http://radiopcp.blogspot.com.

i think some kind of rubber snap-over hook pads that could be put on in a hurry would be a big help. i like the thinness and precision and open sightlines of the plain steel hooks for most of what i do, but a rubber pad would be a big help sometimes. i'm a big fan of body-power [tho i've never used any other kind] because of the fast response and feedback i get through the cable.

hope something in there is useful

bill

[Daniel Paulsen]

Thanks for the feedback. I will definately keep this in mind when/if I get to develop my hook project further. I like the idea of the snap on rubber hook pads.

Did you know that Hosmer has two different flexion wrists? The wrist you have is called the FM flexion wrist. The other wrist is called the Seirra Flexion Wrist which was created by Sierra Engineering Company. Sierra Engineering company is the same company that originally manufactured the APRL hook that Darryl likes. I think that the serra flexion wrist is more popular than the wrist you are using so it might be worth giving a try.

[Bill Taylor]

Hi Daniel,

When I got this pros as a new amputee [4 yrs ago], I was totally clueless about anything prosthetic, as most accidental amputees are...putting us at a huge disadvantage. My prosthetist said that the Sierra wrist was too long, given the length of my stump. Looking at my pros, though, I think it could have been squeezed in there. The sierra model seems to have a sturdier "switch" push button. At any rate, my pros is made, so I no longer have the option to change the wrist. The FW button is connected to the inside lock by two tiny rods...about 14 ga. wire...way too weak to withstand a side impact -- the very type of impact that a heavy object being carried, say at mid-forearm position, would exert if it slid down the inside of the pros, like when you drop a load of firewood for example. Another problem is that things which aren't heavy enough to bend the button [like a cardboard box] are nevertheless heavy enough to push the button, allowing your hook to flop around...not usually a problem, unless the button gets bent ever so slightly, so that it sticks in the "in" position, in which case your hook gets uncontrollably loose at the most inconvenient times.

I'm working on a design for a guard which will either clamp around the wrist like a hose clamp or mount over the front to the 3 wrist screws. A wedge shaped piece of metal would surround the switch, making it more or less flush with the guard, so that it couldn't get a side blow and so you'd have to push the button below the surface of the guard to unlock the wrist. I think maybe the hose clamp style might work better because it wouldn't put additional weight or torque on the mounting screws.

Right now, I'm doing a lot of other things, so it'll be awhile till i can make a working model...meanwhile my button with one wire broken is held together with a wedge to keep it from being pushed in and electrical tape to hold everything in place...not a great solution, but at least I can use my hook in the straight position.

Bill

[Wolf Schweitzer]

Also my Otto Bock wrist started to come loose. We figured it was the way it was built.

So we came up with a simple sturdy wrist and built it (I'm wearing it now). It wedges into a lock with the cable pull. We made it so it'd fit the existing socket / existing terminal devices. If the specs of the socket and the terminal devices are known, it can be easily adapted. The STEP-/PARASOLID-files are online for free download if anyone wants to resize some part and get that milled wherever.

Currently we are building a more complex wrist, one that has full rotation and full lock at any position. That also is compatible with the standard Otto Bock wrist. But we just finished CAD drafting - nothing there to touch yet.

My stump is too long also for a lot of material to be in that wrist. And I want to be able to wear not just a hook but a hand at the correct length.