optional Drag Knife

[acourtjester]

In a post about routing there was info about 2 drag knifes posted, always interested in options I downloaded both sets of files and here is what I found. here are the images of the parts I printed and how I rate them and why. This is the better of the 2 overall better fit of the parts and a complete cover for the utility blade for safety. https://www.thingiverse.com/thing:3978176
This one did not have the good fit for the parts as shown and one of the blade's ends is completely exposed. There also was many unusable files included in the image section. I did however like the Top part and will use it in the final assembly of the drag knife.
This is that site https://www.thingiverse.com/thing:3994417
good one

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not so good

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[robertspark]

funny I printed the one that did not work so well for you.

Its OK, but I don't like the single screw arrangement.... as everything is held on with 1 screw + it depends how you print the part as to how it comes out with regards to squareness (I have a heated bed) + I printed the small and larger thumbscrew / spindle holder and my larger spindle snapped (I had not calibrated my 3d printer when I did it and it was one of the first things I printed..... still learning)

I am going to modify the design and am waiting for some RA2ZZ and RA4ZZ bearings to arrive (1/8" and 1/4" bore) so they will accept a spindle shaft directly (they are on the slow boat from china as they are not common over here being imperial sizes and I did not want to pay for SKF or a quality brand where there is little actual loading on them etc)


I use this model to calibrate my flow now for part fitting
https://www.thingiverse.com/thing:342198

[robertspark]

I have also taken to using these brass inserts with 3-d printed parts and installing them (pushing them in) with a soldering iron

[AREA]

SUPER COOL STUFF GUYS!!!!!!

[acourtjester]

Here is the finished drag knife in the model I printed, I stayed with the original bearing as I had some left over from my wind mill project.
Using this holder the utility blade fits into notches in the body, as shown in the first image.

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[AREA]

Here is the finished drag knife in the model I printed, I stayed with the original bearing as I had some left over from my wind mill project.
Using this holder the utility blade fits into notches in the body, as shown in the first image.
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Phenomenal!!! I'd love to get a 3d printer but afraid I won't have the time for it and it will sit on the shelf with so many other tings I don't have time for.

[acourtjester]

Well at least you have identified your situation, today's times there are to many toys and not enough time to enjoy them.

[robertspark]

For years I did not see the point of a 3d printer.... I mean I can weld, grind, plasma cut, turn and mill..... Why would I want something out of plastic.... That's going to be weak and not very strong.....

Stuff takes ages to print.....

I changed my mind when I thought it may be useful to prototype and make plastic enclosures for stuff

Slowly I accumulated the parts for a 3d printer.. (custom, kinda like a CNC plasma cutter).. It probably sat there for about a year.... Now I have it running I can see the point for quick testing of ideas and mechanisms

(Next project for me is my pneumatic T56 shifter (the transmission end) which I'll do in plastic first and then aluminium or steel once I get the pivot points right as I can adjust and reprint the parts at very low cost..... The printer just runs in the background and sends me a message when it's done or runs out of filament

I am just about to add a second coat of epoxy onto my breakaway plasma z axis machine torch holder which incorporates home, floating head and breakaway microswitches and a crosshair laser mount after sanding the first coat down. The epoxy is more for added strength and longevity than appearance (as it is going on a z-axis of a plasma cutter). I am not sure how it will hold up long term but it's been fun plus I've been learning to use fusion360 as a transition from Autodesk Inventor .... So it seamed a nice learning project and design from scratch

As I printed a few parts as part of the design iteration process they gave me a chance to test the strength of the structure to destruction which was interesting as the internal honeycomb structure is surprisingly strong and the expoxy coating just adds a whole new level to the shell structure strength

[acourtjester]

I got started with 3-D printing about 3 years ago, my wife and I needed to care for my daughter in Maryland which took about 3 months (spine operation). She was into 3-D printing and help me get started, so I would not go stir crazy. I cannot tell you number of handy things I have printed, some of which are shown in another post here. Things like a cross hair laser holder for my table, here is a insulator base for a USB BOB I have used on a few tables. A back scratcher, cover for a voltage regulator, a tool demagnetizer, draw slider, tape measure marker clicks on a tape measure. Very handy tool to make things of your own design or download file from others.

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[SeanP]

Good stuff Tom!!
I like the drag knife, very neat.

[acourtjester]

Thanks Sean
For those that may not know this drag knife is for thicker material not for sign vinyl. That type is posted earlier

[mcmental]

For years I did not see the point of a 3d printer.... I mean I can weld, grind, plasma cut, turn and mill..... Why would I want something out of plastic.... That's going to be weak and not very strong.....

Stuff takes ages to print.....

I changed my mind when I thought it may be useful to prototype and make plastic enclosures for stuff

Slowly I accumulated the parts for a 3d printer.. (custom, kinda like a CNC plasma cutter).. It probably sat there for about a year.... Now I have it running I can see the point for quick testing of ideas and mechanisms

(Next project for me is my pneumatic T56 shifter (the transmission end) which I'll do in plastic first and then aluminium or steel once I get the pivot points right as I can adjust and reprint the parts at very low cost..... The printer just runs in the background and sends me a message when it's done or runs out of filament

I am just about to add a second coat of epoxy onto my breakaway plasma z axis machine torch holder which incorporates home, floating head and breakaway microswitches and a crosshair laser mount after sanding the first coat down. The epoxy is more for added strength and longevity than appearance (as it is going on a z-axis of a plasma cutter). I am not sure how it will hold up long term but it's been fun plus I've been learning to use fusion360 as a transition from Autodesk Inventor .... So it seamed a nice learning project and design from scratch

As I printed a few parts as part of the design iteration process they gave me a chance to test the strength of the structure to destruction which was interesting as the internal honeycomb structure is surprisingly strong and the expoxy coating just adds a whole new level to the shell structure strength

Hi robertspark, did you finish the 3d printed version of the z axis breakaway? im looking to make one when my new printer arrives if you have any assistance please?
thanks

chris

[acourtjester]

Robert Spark has removed his receive contacts from members so you cannot send a PM to him. And he may be to busy to see your request.

[robertspark]

I'll have a look at this later (new job working in health service... bit busy at moment)