Looking for sewing patterns

what you want is a zentai, look up on eBay

Originally posted by Like Ra MrBob, do you mean this one: http://www.likera.com/blog/wp/archives/417

 saw the one picture but never the diagram... that's kinda cool

Hello all. Glad to find this forum.

I found it from the afore mentioned link.  I was there because I was working on my plans to machine the latch mechanism.  I found out that my physics department machine shop is accessible (so long as I don't take time from other students), and I thought, "life has handed me lemons, so I'll make some selfbondage gear."

I plan to machine the mechanism out of aluminum, which given the angle of the arms and potential force will be strong enough.  The lock ability and self latching features will still be there, but it won't have a cable release once latched.

The overall dimensions will be , while latched, 3 1/2" x 1" x 1/2".  There will be points to tie off on the post top and bottom.  To release the setting cable, I plan to have a hook, so you set it while leaning back, then leaning forward will let the cable slip off.

I will probably get enough material for a few of these, at least because this is the first time I have really done any sort of machining, and I will probably screw up a couple.

I'll post pictures as I build the piece, but I already have an approximate schematic so I'll post that after I clean it up.  The design may change after I discuss the plans with the shop supervisor (whom I told that this was a device for hanging heavy sensors from trees ;) ).

If these work well enough,  I can try and contact a fabrication house to do these in stainless steel, in a nicer package and all of the fixings.

I'll keep you updated.

-James

getting the slot in the pin to line up with the latch might be a pain. Making the pin Square with rounded corners or even D shaped would help, but making the holes would be a little harder (you couldn't simply drill them, you would need to cut them the shape of the pin). If you bullet nosed the pin and put a grove in at a little ways down you could add more fingers to the two side pieces and have then act more like a hinge. The latch could be modified to a thinner bar with a u shaped cutout that fit into the grove on the pin. The bullet nose part would push it back and then it would snap into the grove as the pin was pressed in. kind of like a c clip on a hinge pin.

Edited by roboman - Mar-27-2008 at 01:03

MrBob, jgmrequel, any progress yet? I'm very curious...


Edited by Like Ra - Apr-03-2008 at 22:23

An update: partial wooden prototype

I made this partial prototype out of bass wood to help illustrate the sliding mechanism to the shop supervisor.  A 3/4-view plan drawing doesn't quite convey the full complexity of the primary latching mechanism.

My bass wood workmanship needs improvement, I know.

The morning of April 9th, I start working on the piece.  it'll all be aluminum, with exception of the slider, which for strength will be stainless steel.

-James

if you really want a pattern to try then you could look at this one http://www.kwiksew.com/Catalog/cat_detail.cfm?pid=2335&QL=MenSwimActive

As I mentioned in my last post, I've been thinking about how the locking mechanism could be made.

Like many others, I have only access to tools etc. that can be bought from the local DIY store, which has greatly influenced my design. Lamination is the solution I have adopted, i.e. a number of plates fastened together.

The first picture illustrates what the finished mechanism would look like. It consists of 4 assembled parts, the left and right collar attachments, the latch locking pin, and the release screw. When in place, i.e. locked, it will be symmetrical.

I have chosen to use an rectangular section shaped latch locking pin to overcome the problem of a round pin turning and failing to engage. The top of the locking pin could be shaped so that it automatically aligns itself.

The next 4 pictures illustrate the components of the locking mechanism in more detail.

At present, I'm thinking that most components will be made from aluminium, otherwise a very stiff leotard collar would be required if heavier steel was used. Alternatively, high density plastic could be used. The design would probably need to be modified if the components are to be glued together. It could even be smaller.

The first layer, i.e. the left and right collar plates have slots to enable the lock to be attached to the collar by 1.5" webbing. The 6 holes enable the plates to be fastened together.

The second and third layer plates are shaped to have tongues which fit into recesses (top half). The right hand plates have a second recess to house the latch plunger and spring (bottom half), as illustrated below.

The left and right hand collar attachments will be held together by fiction of the tongues in the recesses. When the latch pin is inserted, it will lock the collar attachments together. The pin itself will be locked in place by spring loaded latch plunger.

The plates could be fastened together by machine screws, pop rivets or even good old fashioned rivets, the type you bash with a hammer.

When assembled, the right hand collar attachment will have a 3mm hole drill into the right hand edge. This will allow the release screw to be screwed into the end of the latch plunger. Two possible release mechanisms could be adopted.

1) A release cord attached to a 'full length' screw could simple be pulled.

2) Alternatively, the screw could be removed completely, preventing the sub freeing herself. She must wait patiently for her master to insert a shorter release screw, such that when it is screwed all the way home, it retracts the latch plunger, releasing the latch pin.

As already mentioned, the latch plunger will be made from square bar. To make the retaining lug, a hammer could be used to form a mushroom head at the end of the bar. This could then be shaped to form the retaining lug. Well, that's the plan!

As can be seen, the latch pin is in fact, the top part the the T-piece. The arm binder sleeve, the straps etc. will be fixed to the horizontal bar.

Another eyelet (not illustrated) will be attached to the T-piece, just below the lock area. A cord from the ceiling will attached to this second eyelet. When a sub descends from an upright to a fully kneeling position, she will descend at least 8", closing the leotard's zip, and cinching the arm binder sleeve, straps etc.

The ceiling 'locking' cord will be tied to the eyelet by a special knot which I'm sure I've seen on the internet somewhere. Once the leotard is locked, the sub will then pull on the tail of the cord, which will undo the knot, detaching it from the eyelet (similar to undoing your shoelaces).

And that's it! Simple eh!

Comments, suggestions for improvements, even criticisms welcome!

Time for a pint...

I'm seeking advice on what material to use for the leotard. Ideally I would like to use a relatively thick (1mm-2mm), stretchable (10% or more), shiny, but not too glossy material, similar to that portrayed in the picture...

Originally posted by BDSmanUK The obvious choice is latex rubber, but I'm not too keen on this material. It is too easily damaged, is susceptible to petroleum based products like soap detergents etc.,

True, but you can try thick rubber, like 0.8mm. Or (as a compromise) a 1mm thick vest. Actually, making this construction separate from the leotard would solve many problems.

Originally posted by BDSmanUK and it deteriorates with age.

Also true. But what does not? Lycra, elasthan, nylon die in ~10years too.

It has been quite a while for me.  School has just swamped my time and I have not been able to get to the shop as of late. 

I am interested in seeing the acryl mechanism that you have made. My only concern with the flat design is that there is no apparent way to attach the pull cord. 

With my design, a rounded top ensures guidance into the hole, while the mount to the arm strap will be such as to minimize twisting and allow slight rounded corners to guide everything into place.

As soon as I have more, I'll post it here.

I have access to Solidworks, a 3D CAD package if that would help... 

GoLdStAr