Chamonix and Intrepid rise-fall/tilt knobs

[Peter De Smidt]

Right. Space saving is the best thing about them, including saving the space needed to switch between operating them. That said, I sometimes find that turning one of the knobs affects the other one, and that's no good. On my Intrepid, the front rise/tilt concentric knobs are only ok. The regular knobs are all easier to use, even if they're thinner. Ideally, controls should be smooth to operate with progressive locking. For me, that's more important than space saving, but maybe if concentric knobs are made properly, they'll work fine. On my P2, tilt and rise are concentric..but they're big knobs and using one doesn't interfere with the other.

[andratos]

The style of bolt in the first ali express link looks like it would work well, but if the actual bolt is 12mm diameter, that seems pretty chunky.

Here's pics of what I did. Note the wide plastic piece the hollow bolt is pressed into, with lugs that engage the slot in the standard preventing rotation, just as you suggest. The middle knob has a 5/16"-16 nut pressed in to a recess, and the top knob (tilt knob) has 10-24 cap screw pressed through it. I model the printed parts with slightly undersized holes where the bolts and nut press in, and extra wall thickness, then heat the bolts and nut before I push them into place. The plastic melts and hardens around the steel, and makes a very secure hold. I suppose knobs could be machined from steel or aluminum and bolts and nuts seated with an arbor press, but I doubt the machine work would be cheap.

Attachment 194216Attachment 194217Attachment 194218Attachment 194219

Hello! I know this post is a little bit old, but I am also currently trying to make a LF camera from scratch to 3D print and I am curious about something regarding the dual knobs.
You say that you have a large bolt that you made hollow and that you pass a smaller bolt through this hole. My question is: is this hole threaded or not? If not, where does the smaller bolt thread?

I have made a little CAD drawing to try to understand:


Basically the blue piece is a bolt that has been hollowed and tapped for a smaller bolt (i.e. in this case M6 hollowed and tapped for M4). Then the bolt is somehow joined to the lime piece (the second from the right) while the cyan and orange pieces on the left (which represent the side of the frame where the lens is mounted) are free to rotate. However when you screw in the M4, the pressure against the frame should prevent from moving… but I am not sure if this is how you also designed your piece and I am not sure if it makes sense.

[rfesk]

I will add to the above concerning thread sizes. Often, bolts are available in fine and coarse threads. i.e. 10-24 vs 10-32. I always choose the bolt with the finer thread for more precise tensioning of the locking of movements.

[Tin Can]

Sharpshooters never miss

[John Layton]

I'm with Peter in agreeing that progressive locking (an even/smooth progression, from light to rock-solid) and decisive separation between rise/fall and tilt controls, without risk of coaxial interference, is essential. With this I willingly sacrifice an otherwise admittedly significant amount of vertical linear movement:



Having said this...I do have a trick up my sleeve :

[AuditorOne]

Sharpshooters never miss

Only in the movies.

[andratos]

Excuse me, I am not sure I understood your answers �� Has anyone addressed my question regarding the mechanism of the double knob?

[Tin Can]

Not all use bullets

Sharpshooters are after the fact critics inside

24/7 in shift factories

[Tin Can]

Search McMaster-Carr online https://www.mcmaster.com/products/knobs/

Look hard they have MANY knobs with ALL Specs

Excuse me, I am not sure I understood your answers �� Has anyone addressed my question regarding the mechanism of the double knob?

[Tin Can]

Search McMaster-Carr online https://www.mcmaster.com/products/knobs/

Look hard they have MANY knobs with ALL Specs

eBay has 400 options