[mention]Janger [/mention] have you figured out a price yet? [emoji3]
Sent from my iPhone using Tapatalk
Sent from my iPhone using Tapatalk
-
Spring 2024 meetup in Calgary - date Saturday, April 20/2024. discussion Please RSVP Here to confirm and get your invitation and the location details. RSVP NOW so organizers can plan to get sufficient food etc. It's Tomorrow Saturday! you can still RSVP until I stop checking my phone tomorrow More info and agenda
-
We are having email/registration problems again. Diagnosis is underway. New users sorry if you are having trouble getting registered. We are exploring different options to get registered. Contact the forum via another member or on facebook if you're stuck. Update -> we think it is fixed. Let us know if not.
New Never-Twist clamps
- Thread starter Brian26
- Start date
Got it!
Attachments
eotrfish
Super User
Janger
To confirm...
The handle end of the threaded rod is retained in the square block with a C-clip.
The knurled handle presses on the square block and the rod simply spins inside the block. You got it right. The threaded rod and handle is all one piece.
The far end of the threaded section has a stop washer which is retained by a C-clip.
I think your decision to opt for screws rather than peened rivets is a good one. You can change the anvils to V / Flat / Radiused or whatever your heart desires in less than a minute.
To confirm...
The handle end of the threaded rod is retained in the square block with a C-clip.
The knurled handle presses on the square block and the rod simply spins inside the block. You got it right. The threaded rod and handle is all one piece.
The far end of the threaded section has a stop washer which is retained by a C-clip.
I think your decision to opt for screws rather than peened rivets is a good one. You can change the anvils to V / Flat / Radiused or whatever your heart desires in less than a minute.
The only other thing I'd suggest is how to size a graduated set, like small / medium / large for example. Looks like the width is about 2X the distance between pads & jack screw. So big clamps may not be appropriate for small jobs given the overhang. And when they are wide open you lose a bit of mechanical advantage. Some things may scale, other things (like fasteners, therefore threaded holes, jack screw... maybe even plate thickness) may be different for different sizes. I'm a 1-IKEA wrench kinda guy, but sometimes that's just not possible.
And that is probably why they were discontinued you could probably move the rod to the left of it like the can’t twist because the more you get to the pivot the less clamping force.
you could extend the arm to use the same system as the can’t twist.
John
Wonderful drawings. Very clear and helps me understand that this type of clamp does have a deeper throat when fully open - a big plus, providing you do not have to close it too much. Your red circle concern could be solved the way Dimede did - by using right and left hand threads. If that is not practical for some reason, then this is bound to be an area for concern, because of the tremendous forces involved. You could probably find a solution for up to one ton of force - but this design goes way beyond that, and so a hefty part will be needed here.
Regarding the threaded standoffs - it is a great idea, and the guy in Winnipeg uses that for his design. It is more fussy however and would take lots longer than peening the ends. Regarding peening, I wonder if your fantastic Fusion 360 designs could easily be modified to show a longer end on the 8 standoff pins? Or, alternately, leave them as is and add a threaded hole? Both designs would work well, and any maker would be happy with either choice.
Great work - and I like the way you think!
P.S. - I plan to take some more detailed pictures of the clamp I made and post them. Maybe later today?
Kevin
I did not want to be too forward on this forum, so I put the prices in my PDF attachment. Let me know if I should send you that file separately, and I will gladly do it. Would need an e-mail address - it is way too large for a phone to handle I think. Cheers, Brian
John
I made my first one .060" - but that is too long I think. .040" should be about right.
More Pictures!
Attachments
John
To make the arms look like the picture, I used a 1" abrasive pad I got from Amazon in my milling machine - but any drill press will do this. These pads screw into an adaptor which you also need. I bought a package of 30 pads at once, and the first pad did all four arms, and still has life left. I free-handed the whole process, moving the arm perhaps 5/8" each time. Each "scratch" took only a few seconds.
Regarding the aluminum standoffs, I had not thought about aluminum - but it should work well. I think it would lower the strength a bit, but the savings in time might be worth it. One thing I do know from being almost finished making the second clamp (with the fancy-looking arms) is that it is a challenge to drill and tap a hole into steel for a 10-24 bolt. If I recall correctly, you intend to make a clamp using threaded ends on each standoff - an elegant solution I believe.
I think that aluminum would work very well if, like John you intend to drill and tap the standoff ends for small bolts to hold things together, and not use peening like I did. I think aluminum might be too soft for peening and so I did not even think of that. I now am thinking that brass might be better than aluminum? Very easy to machine, drill and thread. For the record, I have made the central pivot for my second and fancy clamp from brass. There will be pressure on this pivot point, but the diameters are large enough so it should not be a problem. We shall see...
Kevin - Prices are included in the .pdf document I posted initially. Hope that helps.
Busy yesterday and today making the "internals" for the second clamp. Ready now for the installation. I made the handle so that it slides this time around. Also used 7/16-14 threaded rod instead of 7/16-20 so the clamp will open and close faster. Have a look:
