Cranequin (WIP)

Hey Guys!


Thanks to Jokum -who inspired me a lot with his project- I recently began working on my own cranequin.

I´d like to invite you to follow the construction on the german board where I report abut the steps in detail.

I think the pictures say more than words, so I am not worried about the language difficulties, otherwise just ask.

Generally I do the work close to Jokums description with some little differences, so again tribute to him.

The finished product will be presented here when work is done.


http://fletchers-corner.de/viewtopic.php?f=34&t=23434


Some impressions of the current work:





Greetings Rizzar

Hi Rizzar!

That's quite a project... Good luck!
What amazes me is how do you manage to make the teeth of the wheel and the rod so accurate as if they were made by industrial machinery.
I'm curious to know...

ZigiMan

Hey Zigiman!

Thank you.

I am lucky to have access to a manual milling machine which is like a very good and accurate drill press.
I made the circular drillings of the wheel with the help of a splitting device that provided me with a correct 360° alignment.
The rod itself was just drilled with the same distance from hole to hole.

But after drilling I grinded the teeth out with a better belt grinder.
At this point best care and attention was paramount.

Going to continue tomorrow with the rough work on the housing.
This thing has to be finished in the near future.

Greetings Rizzar

So far, so good...




Rizzar

In practical Engineering,there is a hierarchy,and top of the tree,and the most skilled,is the Toolmaker.The standard of your work is that of a highly skilled toolmaker Rizz,I don't know what you do for a living,but if you're not a toolmaker by trade,your work is remarkable,as is your patience.Regardless of what you do,your work is of the highest standard,and an inspiration to everyone who builds,or wants to build crossbows.
                                                              Hermit.

I forgot a question Rizz,are you going to heat treat the rack and pinion on your cranequin?
                                   Hermit.

Thanks Hermit

I spent my last 11 years in the german army. Before that I made an apprenticeship as electrician but that was too long ago to have any benefits.
I am considering doing a bachelor in mechanical engineering after my watch ends.
But In fact, no I never learned it, it is all time, patience and accurateness^^
And of course plenty of old, cool machines my father began collecting decades ago which I am participating in.

Since this model is completely made from mild steel and I assume not to exaggerate the load I do not plan to do some case hardening.
But I will have a look on the mechanics when operating.
Either it works out or I will consider building a new cranequin from higher grade steel sooner than I am planning right now.
This one is for gaining experience, personnaly I plan building 2 more cranequins, one with an opened housing, and one for very high loads using a worm drive)

Rizzar

Awesome and  beautiful! It is one of the  thing in crossbow building that I never dare to do! It is really fun to see your work detail. Machinery is certainly a great help but patience is the fuel !!!

I think you're right Rizz,as your cranequin is a prototype,and not going to be used to much,you don't need the wear resistance case hardening will give.
                                               From your basic biography,I was surprised how much we have in common,I spent 10 yrs. in the British Army,4 of them in Germany,in Krefeld,and Moenchengladbach.I started out in the Royal corps of signals,as an Electrician/Driver,then transferred to the R.E.M.E(royal electrical and mechanical engineers)where I did most of my service until discharge.I came to Canada{Northern Alberta}in 1990,and have been here ever since.Your cranequin is an excellent example of what can be done with patience,care,and hand tools(although you did use a basic milling machine)having done that sort of thing myself,I can appreciate the time,skill,and patience involved.
                          Hermit.

Hey there!

Update and done!








@Hermit: yeah, always interesting when realizing someone on the other side of the ocean with nearly the same interests has a similar biography


Greetings Rizzar,
who is very happy of having finished this incredibly long, exhausting work.

Rizzar,

      WOW ! A work of art ..........just beautiful ...... such craftsmanship !

Chaz

What to say more !!! Superb.... Is it possible to have a picture with the cranequin spanning a crossbow?

Beautiful craftsmanship. What is that triangular bit between the hooks?
Gnome

Hey guys, thank You!

Unfortunately I do not have a to the configuration fitting crossbow right now.
So showing it spanning a crossbow will take a while since I dont want to modify some existing for the required longer (compared to goats foot lever) knob distances. (resulting due to the long claws of the cranequin)

Perhaps I start a new build during the holidays, but unless I do not have proper tilller wood in stock there could be delay or difficulties. (besides I intended to build a spanning bank first)


The triangular bit between the hooks is a so called "Zeigeblättchen" (german but recently not translated in the lecture I own).

In translation I think "index plate" will do its duty.
It is a small plate that helps one to control wether the sting is moving on the tillers center or is alternating to a side. If applied to the sting it should be on the centerline of the tiller and whilst spanning stay there to prevent horizontal movement of the string and attached bolt while acceleration.

Most of these plates on original cranequins have been lost during the centuries, but some still have or do at least have evidence of being equipped with one before (small drill holes in claw flanks).


Rizzar