Thought you guys might like to see my new & improved process!

[aarongough]

Hey all!
So I spent most of June completely re-building my process for making my knives from scratch! It was a big leap, and a bit of a risk doing so, but it turned out to be totally worth it!

I have been using CNC for a lot of my process for the last year or so, but the previous processes were always very fiddly keep running right. A tiny variable changing here or there could really throw things off and because of that I have scrapped a lot of blades over the past year, probably close to 100 blades went in the scrap bin because of various problems in fact. However during all these issues I was making sure to take notes and think about what improvements could be made.

One of the big issues with my old process was that when the CNC machine was running I had to stand next to it and change parts every few minutes. It was never running in parallel with other things... Commercial machine shops have a measure of efficiency that they call 'spindle uptime', which refers to how long each day the CNC machine is running for. When I worked out my spindle uptime over the course of an entire batch it was very low (around 8% or so) because when the machine was running I wasn't doing other things, and when I was doing other things the machine was not running.

So when I set out to design the new process I had a few goals in mind:

1) The CNC part of the process should run 'unattended' meaning that I don't have to stand in front of the machine and change parts all the time
2) The CNC part of the process should be super robust and reliable, it should not need constant tweaking to keep running correctly
3) The new process should produce knives that are better and more consistent than anything I've made previously
4) The new process should empower me to do other things in parallel, and reduce the amount of 'batch work' which I find very stressful (sandblasting for days on end is no fun!)

With these goals in mind I decided to make a large 'fixture plate' that would mount to my CNC machine, it would have stations for each of the CNC processes that I do, and as such every time the machine would run it would turn out 1 blade ready for hand sanding and 1 pair of handle scales ready to go on a knife.

First up was initial concept sketching, very crude I know!


Then I started building the 3D models using my CAD program (Fusion 360). I ended up re-designing all of my 3D models for the knife and all associated parts during this process, as my original 3D drawings were less organized than I would like:


After the CAD models were completed and it all looked like it would work, I started making the various parts of the fixtures...

The top clamps for the beveling stations. These are made from A2 and received a heat-treatment and spring temper:


The side clamps for the beveling stations, these also got heat-treated:


Exchangeable pallets for the handle scale machining:


The base plate for the fixtures (this is a 1x10x22" slab of 6061-T6 aluminum!):


Here you can see all the fixture parts before assembly. The individual stations are made to be replaceable. They're made from 1018 steel blanks that are bolted onto the aluminum baseplate. The assembled fixture weighs close to 90lb:


The fixture plate was then assembled and located on the CNC table via a pair of locating pins:


The fixture was then machined 'in place' to ensure the highest possible level of accuracy. Here you can see the first step, cutting the tops/sides of all the fixture blocks:


All of the fixture stations then had their individual machining done. Machining everything took about a day as I was being careful not to muck anything up:


All of the 1/4-20 holes were then tapped by hand and the fixture was fully assembled:



The side clamps (spring-loaded clamping cauls) for the beveling operations are part of the secret sauce of this fixture plate. They let me hang onto the spine and edge of the knife to provide 100% access to the bevel without marring the knife. The spine side is made from hardened A2 and you can see how it operates in the GIF below. The edge side of the clamp is stationary and made from a replaceable insert of 4140HT steel so that it won't get worn out too quickly by the clamping force applied to such a tiny area (just the 0.015" thick knife edge):

The final fixture plate consists of 6 stations for 6 operations:
1) Machining of the weight relieving cutouts, pin holes and lanyard holes
2) Machining the spine of the knife along with the right hand side of the windowbreaker bevel
3) Machining the edge of the knife and the left hand side windowbreaker bevel
4) Machining the left bevel
5) Machining the right bevel and engraving my logo
6) Machining the handle scales

Each time the plate is loaded each knife blank moves one station to the right, across 5 machining cycles it will go from a raw rectangular blank to a knife ready for hand-finishing and heat-treatment! This eliminates the need to work in batches and allows me to make constant small improvements to the process as I work which has turned out to be invaluable!

Here you can see one of my Resolute MkIII knives as it comes off the CNC machine (top) and how it looks after hand finishing to 220 grit (bottom):


The handle scales are now completely 3D contoured using the new process, which means that I can include a lot of small details (like smooth blended corners and so on) that I wasn't able to previously. The handles now come off the machine looking like they used to after I did the hand finishing on them in the old process:


So far I'm incredibly pleased with this process. After some small tweaks it is running really consistently and turning out really awesome blades! The CNC machine runs for 2 hours to complete all the steps on the fixture plate, and during that time I do hand finishing on the last blade that came off the machine as well as various other parts of the process on blades at various stages of completion. My 'spindle uptime' is now close to 80%, up from around 8% with the old process, which is amazing!

The new process really spreads out my efforts and breaks up the day, which makes life far more pleasant than it used to be. Standing in one spot doing one small part of the process for days on end was really not fun, now I get to do lots of different stuff all the time which is great!

I plan to make a video showing the fixture plate in action soon, I will post it here when I do so!

Anyway, hope you enjoyed seeing the new process! As always I'm happy to answer any questions you guys might have!
-Aaron

 

[AVigil]

I have enjoyed watching on your learning process.

To be honest it seems to be about the hardest way, time consuming and costly way to make that style of blade.

As long as you are enjoying your journey is what is important and thanks for show us your process.

 

[aarongough]

I have enjoyed watching on your learning process.

To be honest it seems to be about the hardest way, time consuming and costly way to make that style of blade.

As long as you are enjoying your journey is what is important and thanks for show us your process.

Haha, yes I won't really disagree with you on that! It is certainly much harder to get a process like this running than it is to simply make them by hand...

However, once the process is up and running it is much more pleasant to keep it running than it is to keep churning along cranking out the same knives by hand, and this was really the thing that drove me all along. I really like the difficult technical side of designing a process like this, all the thinking and machining and refinement, and I really don't like the monotony of repetitive hand-work, so making knives this way really suits the way my brain works! It also makes it possible to make more knives than I could by hand, once the process is actually running at least!

Also a process like this makes for a level of consistency and repeatability that simply isn't possible by hand, and that is also a goal of mine because I want the knives I make to be as true to my design as possible!

I am definitely enjoying the journey! It has been a pain in the @ss at points, but I'm learning a huge amount and I really enjoy the process!

-A

 

[aarongough]

I have enjoyed watching on your learning process.

To be honest it seems to be about the hardest way, time consuming and costly way to make that style of blade.

As long as you are enjoying your journey is what is important and thanks for show us your process.

I should clarify: Hardest yes! Most costly and time consuming, no... Doing things this way is costly and time-consuming up-front, but the time/investment sunk pays back over time just like with any other tool!

 

[AVigil]

I should clarify: Hardest yes! Most costly and time consuming, no... Doing things this way is costly and time-consuming up-front, but the time/investment sunk pays back over time just like with any other tool!

I guess if you are going to make a few thousand of the same pattern it will all even out one day. But 100 thrown away blades is approx $30,000 potential income that will never been seen. Not to mention the knife hobby is always evolving looking for new patterns and trends.

Your blade is a nice blade, it is a pattern many of us have used or a variation of over the years. How quickly can you adapt to a new pattern and how long before it becomes profitable?

Do not get me wrong, I like what you are doing and know many knife makers doing similar but they often are machinist by trade and built a customer base before diving in completely as a full time maker.

Maybe you can give us a peek at your next design you have planned.

 

[wizzer]

Aaron, it has been a pleasure watching some of your threads over on practical machinist as well as your YouTube videos. I am very impressed with your approach to manufacturing and design. As a machinist first and foremost it's cool to see how much you're able to get out of your equipment.

As far as your design, it's refreshing to see someone build a tool that is clearly designed with use in mind. It's a great looking knife, but your torture test proves that it's not just meant to sit on a shelf and get ogled.

Adam, wont to functionality of a knife like this make it timeless?

I don't want to derail this thread, but i would love to hear more about your past and how you became so proficient in machine shop skills.

 

[aarongough]

I guess if you are going to make a few thousand of the same pattern it will all even out one day. But 100 thrown away blades is approx $30,000 potential income that will never been seen. Not to mention the knife hobby is always evolving looking for new patterns and trends.

Your blade is a nice blade, it is a pattern many of us have used or a variation of over the years. How quickly can you adapt to a new pattern and how long before it becomes profitable?

Do not get me wrong, I like what you are doing and know many knife makers doing similar but they often are machinist by trade and built a customer base before diving in completely as a full time maker.

Maybe you can give us a peek at your next design you have planned.

This kind of process is fairly well suited to making hundreds of a particular model, it need not be thousands. Now that I have this general concept down I could adapt it to a new design in a few weeks if I so desired. The 100 blades that were scrapped happened because I was learning a lot of new skills all at once, not something that's fundamental to this kind of process.

However with that said I do not plan to introduce a new design of fixed blade to replace the Resolute. The Resolute design as it stands is an excellent outdoors utility knife and I plan to evolve it slightly (possibly a new steel next year after I do more steel testing, and maybe a slight change to the bevel geometry) but I do not plan to replace it. I like the idea of a design that is produced essentially unchanged for years. Many older companies used to do this, and I like that approach to design. If it ain't broke, don't fix it. I think changing things just because it needs to be 'new' as opposed to because there is some fundamental improvement to be made is a bit nuts...

That said I do plan to start making other models that will have entirely different uses. Ultimately I plan to make a lineup of 3 different knives. The Resolute, an EDC folder yet to be designed, and a kitchen knife (likely an 8" santoku, this is already prototyped and being used every day in my kitchen and a few others).

 

[aarongough]

Aaron, it has been a pleasure watching some of your threads over on practical machinist as well as your YouTube videos. I am very impressed with your approach to manufacturing and design. As a machinist first and foremost it's cool to see how much you're able to get out of your equipment.

As far as your design, it's refreshing to see someone build a tool that is clearly designed with use in mind. It's a great looking knife, but your torture test proves that it's not just meant to sit on a shelf and get ogled.

Adam, wont to functionality of a knife like this make it timeless?

I don't want to derail this thread, but i would love to hear more about your past and how you became so proficient in machine shop skills.

Thanks mate! I always love getting to share this stuff, so thanks for following along!

I do wish I had a bit better equipment to play with. If my mill was in better shape I'd definitely be looking into hard-milling the blades, but that's something I hope to look into in the future!

Design for use is definitely always first and foremost in my mind... My ideal customer is someone that uses their knives all the time and uses them hard. I'm lucky enough to have a lot of customers like that, and I hope I will get more! I too hope that a knife like this, designed with utility being the first priority, is essentially timeless. I'm sure I will find new materials/coatings/etc as time goes on but I do not feel any need to make big changes to the design as I'm very happy with it as it is.

My background is actually all over the place. I don't have any formal education beyond high-school (which I will admit to barely passing). After that I worked in a variety of different fields including sales, construction, warehousing and in a guitar factory to name a few. After I moved to Canada in 2006 I ended up specializing in software engineering (web application development) for early/mid-stage startup companies. I did that for about 6 years before I'd had enough of the crazy treadmill that is the startup world and decided to make knifemaking my full-time gig.

Knifemaking has been something that interested me for a long time. When I was 14-15 I spent a few hours every week for a year with an Australian knifemaker named Neil Charity. He was exceptionally good at what he did (beautifully inlaid lockback folders for the most part) but I was really too young to absorb much from him, but that time definitely built groundwork that I was able to build on later. My father and grandfather are both quite handy in a workshop so I learnt bits and pieces from them when helping repair cars and so on. When I worked at the guitar factory they had a huge 5 axis CNC router that totally captured my imagination, I was rapt with CNC from that time on.

I got back into knifemaking as a hobby about 3-4 years ago, at that time I was renting part of a shared workshop and had dabbled with some small home-built CNC routers as well. From there I basically learnt via trial and error and lots of time spent on the internet doing research... Before I got my VMC (~16 months ago) I had never seen a big CNC mill in the flesh, let alone run one, so that was a huge learning experience. I had run a small manual mill/lathe but that was it. As you can imagine there's been lots of moments where I had no leg to stand on in terms of experience, but luckily the internet is an amazing tool for researching all kinds of things... Everyone here and over at PracticalMachinist has been amazingly helpful as well!

 

[Kevin McGovern]

If I'm not mistaken, he has a waiting list? They are in demand regardless

 

[AVigil]

I think changing things just because it needs to be 'new' as opposed to because there is some fundamental improvement to be made is a bit nuts...

That is not why you change, you change to progress and grow and not remain stagnant. "Fundamental improvements" are often due the"New" developments.

The reality of being in the custom knife hobby for over 35 years collecting and now making is diversity is king, mulitple money making streams from different designs is one of the key things that keep bread on the table and the lights on for a knife maker.

 

[J. Doyle]

Having a great selling pattern is a good thing. But if you're in it for the long haul, you will want some variety. People's tastes in ANYTHING is so varied and unpredictable and an individual's tastes change over time. You may have no end in sight for orders for Resolutes but eventually (the day will probably come soonner than you might expect) you will sell one to everyone that wants one and your buying pool will dry up. Very few people will want another of the same knife and there are doubtless hordes of people that would buy one 'if 'X' was different' or 'if 'Y' was changed slightly' or 'if 'Z' was a different material'.

You will want to change eventually to keep things fresh or you will stagnate... eventually. I don't see a way around it. Don't paint yourself in a corner by being so rigid on one exact design. You're keeping yourself from a large part of the market if you do.

You got some mad machining skills by the way. Cool thread.

 

[kuraki]

Great fixture design. It has all of the features I would want to include on production tooling. Repeatable holding, interchangeable pallets (I think? It looks like that for your scale station). The only thing I would have done different, is to make the blade stations a little less model specific. With minor changes, simply by switching clamp plates you could do 100 different blade variations on that fixture. Maybe you still can. Oh, and a station for establishing your holes in your scale blocks. Where are you doing that?

 

[navman]

Aaron, you give us shadetree, garage steel butchers inspiration, from hand filing to CNC with continued high quality and attention to detail....Bravo sir!

 

[Kevin McGovern]

I would think that the processes Aaron is developing for the Resolute 3 could be adapted to other designs pretty readily. Having one design currently takes out a lot of variables at the moment. Just my observation.

 

[kuraki]

The process surely it's transferable. There are just some small things about the base plate that appear model specific but did not need to be.

I'm all for reducing variables on process introduction. It appears he's done an excellent job at that.

 

[Horsewright]

Always enjoy reading your posts Aaron!

 

[jdm61]

Cool stuff as always. How are you machining the bevels as they look pretty darn spiffy coming right off the the CNC machine!!!! Could you just throw them in a tumbler and remove the tool marks if you chose to do so? Those scales look good!!!! How much
more 3D" can you go as far as shaping and still maintain that level of fine finish?

 

[Jonathans]

As a novice machinist I must say that your skill and machining setup and process is quite awesome. I'm sure that once you have this style under your belt other styles will emerge. Eventually you will have a repetoire of blades and fixtures ready to go based on their particular demand. As long as the numbers work out, it seems like a sound model to me.

 

[KnuckleDownKnives]

Aaron, that is quite impressive. I can see the potential this has for future expansion as far a styles/patterns. A matter of machining different fixtures and different CNC programs to machine them. This has very good potential for small to medium scaled production.

In my days in manufacturing working in my grandfathers shop building air ride 5th wheel hitched I started out marking every part to be cut, drilled and welded by measuring each individual cut, hole and fitting to be welded by manually doing each part. It would generally take me about a week to produce enough parts for 4 hitches and weld them up, and no two were identical so fitting the upper half to a base that wasn't fixed and welded together were virtually impossible. I spent a couple months after hours designing fixtures that either went into a saw, a drill press or a mill or cut with a plasma cutter that would hold a length to be cut, a shape to be cut or a hole to be drilled in the exact location as the next and a fixture to hold all the parts in an exact location during the welding process. This brought my productivity from 4 hitches a week to 40 hitches a week, and every part was now interchangeable from one to the next. Different and lighter duty models simply used different fixtures. We were very close to having robotic welders but opted not to spend the million dollar price tag for the tooling. If I could have only figure out a way to automate grinding and sanding..

 

[aarongough]

That is not why you change, you change to progress and grow and not remain stagnant. "Fundamental improvements" are often due the"New" developments.

The reality of being in the custom knife hobby for over 35 years collecting and now making is diversity is king, mulitple money making streams from different designs is one of the key things that keep bread on the table and the lights on for a knife maker.

Fair enough, I get what you're saying! I will make sure to keep it in mind!