CRK Umnumzaan Full Back Spacers...

[BOOMER52]

Just finished up the prototype back spacer for the Umnumzaan. Low profile cogged and smooth designs in G10 or carbon fiber will be available in the near future...

 

[unwisefool]

Does it work with the Tanto blade as well?

 

[BD_01]

Cool.
I dig the orange too.

 

[BOOMER52]

Does it work with the Tanto blade as well?

The design was arrived at using the clip point blade so I can't answer that question.
I would need a 1:1 CAD file of a tanto blade or the blade on hand to insure fitment/clearance.

 

[unwisefool]

The design was arrived at using the clip point blade so I can't answer that question.
I would need a 1:1 CAD file of a tanto blade or the blade on hand to insure fitment/clearance.

Ah ok, thanks for replying!

 

[RTedder2]

I don't know if it'll help or hinder you, but the Zaan can use a body screw in the lanyard hole. CRK sells them from their website

 

[unwisefool]

I don't know if it'll help or hinder you, but the Zaan can use a body screw in the lanyard hole. CRK sells them from their website

Yep, that's how I have mine set up!

 

[BOOMER52]

I don't know if it'll help or hinder you, but the Zaan can use a body screw in the lanyard hole. CRK sells them from their website

That's a great option to have...!

It's a simple thing for me to change the hole diameter in the code so that the back spacer can be machined for either option. I will offer both when I get to the point of batch machining these up.

 

[unwisefool]

Do you make it in a glow material at all?

 

[BOOMER52]

Do you make it in a glow material at all?

The moonglow is an acrylic cast plastic having no internal structure. It is highly susceptible to fracturing with a shock load.

The long persistence moonglow I have on hand is not thick enough at .125" nominal. The back spacers require .154" to .165" depending on model.

It would require laminating two layers to achieve the required thickness... and then double sided thickness machining to maintain a perfectly centered bond line. Same issue if you laminate a centered colored liner OR sandwiching the moonglow.

Anything other than perfectly centered for the bond line would be an assault to the eye when installed.

 

[BOOMER52]

After evaluating the prototype design I've found this full length spacer which has a considerable cantilevered arm will flex at the pivot end. The forward end of the spacer will depress with finger/thumb pressure. There is NO potential breakage issue... it just flexes a bit.

My MKII design attempt to remedy this was to add beam depth creating additional stiffness however G10 still exhibits this slight depression flex even with this additional depth in the beam. Outside of shortening the back spacer to maybe half the arm length I don't see a fix.

I do not find this to be a huge negative. If you desire a FULL LENGTH back spacer for the Umnumzaan this slight flex is part and parcel... however I'm not certain how this with play in the CRK community.

 

[dilla]

After evaluating the prototype design I've found this full length spacer which has a considerable cantilevered arm will flex at the pivot end. The forward end of the spacer will depress with finger/thumb pressure. There is NO potential breakage issue... it just flexes a bit.

My MKII design attempt to remedy this was to add beam depth creating additional stiffness however G10 still exhibits this slight depression flex even with this additional depth in the beam. Outside of shortening the back spacer to maybe half the arm length I don't see a fix.

I do not find this to be a huge negative. If you desire a FULL LENGTH back spacer for the Umnumzaan this slight flex is part and parcel... however I'm not certain how this with play in the CRK community.

BOOMER52 are you still making these and do you take orders?

 

[BOOMER52]

I am no longer machining back spacers for CRK knives...