Who needs chickens...

[Burkhardt]

Another one of my weird projects. Recently I wrote some special software to cut bevels on rectangular parts with rounded corners. But it occurred to me that I can make round parts as well if the rectangle side length is zero and only the rounded corners are left.

So, while Easter is still a few months away, I think this can be used this as a jewelry box..

Blank from 2.5" square curled maple.
https://lh5.googleusercontent.com/-AWDramVE8s8/VGb-JwKSYRI/AAAAAAAAFaU/Q4gNo5CnE2I/w972-h853-no/DSC02849.JPG

Outside top cut:
https://lh4.googleusercontent.com/-u8bTowEOj8s/VGb-MYdX0lI/AAAAAAAAFac/WwsgHYL4x7Q/w1137-h853-no/DSC02851.JPG

Top and bottom piece:
https://lh3.googleusercontent.com/-kQ1U-mh3jsU/VGb-YI_0sII/AAAAAAAAFa8/-ylOTDFK_cY/w1172-h853-no/DSC02854.JPG

Jam chuck to conform with outside, used for inside machining:
https://lh3.googleusercontent.com/-IUPwShViWW8/VGb-SYn47gI/AAAAAAAAFas/9qIyyKBREmw/w1315-h853-no/DSC02858.JPG

[Burkhardt]

Machining the inside:
https://lh4.googleusercontent.com/-Cy7ULidLqII/VGb-Pa4xcMI/AAAAAAAAFak/DgBEwtzFM6k/w1072-h853-no/DSC02857.JPG

Both half parts (only Danish oil so far):
https://lh5.googleusercontent.com/-AKxytUuFTmA/VGb-ZgcBJ7I/AAAAAAAAFbE/hOWn88FFLlM/w1519-h853-no/DSC02862.JPG

Bottom part is still too deep....But not so bad, after all:
https://lh5.googleusercontent.com/-L_Ebibh9Gz0/VGb-UMMs38I/AAAAAAAAFa0/U3WD6ILjwrM/w1101-h853-no/DSC02861.JPG

[myxpykalix]

You CLEARLY have too much time on your hands!!!:eek::D

That looks great. I can see other applications for this. I'm unclear on your holddown method?:confused:

[scottp55]

Jack, I can't wait to see what Gert does when he retires:eek:
G. , Is that a continuous spiral pass with the cutter sides getting into the act as it descends?
OR more of a exterior pocket cut going down layer by layer with a Z-retract after each pass and pass depth being used as your stepover?
How did the waste react-I guess I'm wondering if cut is dependent on the cutter length equaling height of object to be successful.
What was cut time for say 1 exterior?
Was interior done by spec'ing inside vs. outside line, OR - vs. + value?
When are you going to offer a Beta with Free License to the first four people to make an egg or sphere? :)

[Burkhardt]

You CLEARLY have too much time on your hands!!!:eek::D

That looks great. I can see other applications for this. I'm unclear on your holddown method?:confused:

Well, the nice thing about doing this as a hobby is I can spend as much time on such things as I want without worrying about it being profitable. As for Scott's question about my retirement, many people I know suddenly don't have time anymore when they retire. Given that I might start a business then, it may happen to me, too.

Hold down for the outside cut is just 2 screws through the mounting plate. The screw holes are later cut out with the inside material.

Hold down for the inside cut is that jam chuck (or receptacle). It is just a negative surface of the outside and conforms exactly with the part. 3 strips of masking tape make for a little interference and the part is jammed in with a hammer. I still need to work on that and make it 2-part for easier release. Right now I have to split the board to get the part out again.

[Burkhardt]

Oh, lot of questions. See below


J.....
1 G. , Is that a continuous spiral pass with the cutter sides getting into the act as it descends?
2 OR more of a exterior pocket cut going down layer by layer with a Z-retract after each pass and pass depth being used as your stepover?
3 How did the waste react-I guess I'm wondering if cut is dependent on the cutter length equaling height of object to be successful.
4 What was cut time for say 1 exterior?
5 Was interior done by spec'ing inside vs. outside line, OR - vs. + value?
6 When are you going to offer a Beta with Free License to the first four people to make an egg or sphere? :)

1: Kind of. They are loops along the surface on one z-level and then going one level down for the next loop
2: No
3: Correct, right now I can go as deep as the flute is long. The stepover is small and I can machine with the entire flute length. For the oval part I had to rough out some of the innards first to avoid the shank rubbing. I will add that roughing feature to the program.
4: The inside machines in about 2 minutes, the outside in 5 minutes. Outside is slower because the stepover must be smaller for the same surface ripple. However with that aggressive inside machining I had trouble holding the part in place on my slippery aluminum table. I need to use t-bolts instead of clamps.
5: Yes, I can spec inside vs. outside. Otherwise I need to specify the part dimensions, depth, corner and bevel radius (or 2 radii for oval shapes)
6: Have not even thought about it. I just started experimenting with what it can be used for. Next test will be some bowls and rounded boxes.

[Burkhardt]

No eggs this time but a squarish bowl. This is a 6x6x2" piece of wood that I bought as a turning blank some 15 years ago and I have no idea what it is. Very dense, hard and no pores. Anybody knows what species that might be? Please bear with me, lot of pics but I thought some might find the process interesting:

Started cutting the outside shape:
https://lh3.googleusercontent.com/-LPsiGVkAJAE/VGgWPpEEdSI/AAAAAAAAFbk/X_WiKLNJX6o/w1172-h853-no/DSC02865.JPG

Outside complete:
https://lh5.googleusercontent.com/-1qEfcgalKkU/VGgWS6fyOfI/AAAAAAAAFbs/EC2TrogAmhw/w1065-h853-no/DSC02867.JPG

A bit shiny already after 220 grit sanding:
https://lh5.googleusercontent.com/-LnX-LbX7TDU/VGgWVwOxx1I/AAAAAAAAFb0/NhQMvXr_fL4/w1068-h853-no/DSC02868.JPG

Cutting a negative shape of the bowl outside as vacuum pod adapter:
https://lh5.googleusercontent.com/-N6vxpBoSMIA/VGgWX9FyJQI/AAAAAAAAFb8/1_uGUK1N648/w1362-h853-no/DSC02870.JPG

[Burkhardt]

Holes for vacuum connection drilled and gasket applied:
https://lh3.googleusercontent.com/-WfyHZiksVRo/VGgWZ9PNh6I/AAAAAAAAFcE/Sd_KnsgaCzg/w1462-h853-no/DSC02871.JPG

Started inside cut:
https://lh5.googleusercontent.com/-yLV5lOsZmg4/VGgWcmDTGnI/AAAAAAAAFcM/yvqaJmbpKlc/w1137-h853-no/DSC02873.JPG

Inside almost done:
https://lh4.googleusercontent.com/-Jax_t7icYFU/VGgWf-iX3JI/AAAAAAAAFcU/FUlpX2xZy1M/w1214-h853-no/DSC02875.JPG

And....finished. Very little sanding left to do:
https://lh3.googleusercontent.com/-hgCG9wc45c0/VGgWis2oAUI/AAAAAAAAFcc/LNaPeKHAh1U/w1143-h853-no/DSC02876.JPG

[Burkhardt]

A little carnauba wax goes a long way, no other finish:
https://lh4.googleusercontent.com/-1vMiEoZcm2g/VGgWk-bwdHI/AAAAAAAAFck/lU47MmTSnho/w1105-h853-no/DSC02878.JPG

Bottom side:
https://lh3.googleusercontent.com/-ID5us5nhi7w/VGgWnODNQWI/AAAAAAAAFcs/XP_cPcRwFrU/w969-h853-no/DSC02879.JPG

Really wondering what kind of wood that is:
https://lh6.googleusercontent.com/-XpGuReCZweU/VGgWquDHQvI/AAAAAAAAFc8/WioMnksV9xE/w1381-h853-no/DSC02882.JPG

[scottp55]

NICE G. ! :)
Almost like the bottom more than the top. Like how you lucked out with the "Drainage Feature" location, very pleasing to the eye.
Was that- the melted/brushed/heat gun method? or did you make/buy a Carnauba paste first? Been playing with immersing buttons in molten "glass fill"paraffin and after 4 dozen got it down pat for exotics- trick is to let the wood get enough heat so all wax can be wiped off with paper towel before button cools down-soft boar bristle hair brush removes/buffs wax in tiny features. Thanks:) Going through the "Woolite washing" tests now, and they still look good after 2 washings, but going for 6.
Wood reminds me of my Olive kitchen utensils when they were new?
Like how you had enough faith to do good wood:)
Elegant!
scott

[Burkhardt]

....Was that- the melted/brushed/heat gun method? or did you make/buy a Carnauba paste first?
No, just off-the-shelf carnauba polish, rubbed in with a rag:
http://ep.yimg.com/ay/autopia/mothers-california-gold-pure-carnauba-paste-wax-6.jpg

[srwtlc]

G, it looks like it could be Myrtle wood. See it often in northern California and Oregon. Beautiful stuff! I brought home a large bowl blank several years ago and I had to sit on my lathe to keep it from bouncing across the floor while I roughed it out. :)

Nice work there!

[Burkhardt]

Still undecided about the wood. I have some myrtlewood pieces that look similar, but with more open grain and maybe not as hard. Not sure about olive with the color but who knows...

In the meantime I bought an extra long ballnose bit to make deeper bowls and boxes with this method. Got a real good deal for a 6" long 1/2" diameter bit with 3" long flutes. Got it from Toolmexonline (http://www.ebay.com/itm/161467461433#) on eBay for $37, not too bad for such a massive bit, even TiAlN coated. Made in India.....

https://lh3.googleusercontent.com/-ekUVEuN7kRo/VG7NIpmpg6I/AAAAAAAAFd0/o_QwpfjjB68/w604-h389-no/DSC02890.JPG

[Burkhardt]

First attempt at trying to use this extra long ball end mill. Works pretty good but I noticed I need to change the cutting strategy for vertical walls. When cutting a deep slot (the top section of the inner surface) such a long bit starts to chatter like crazy, especially when working at 45 degrees angle to the grain (this is pretty soft western cedar). I suppose the flutes engaging with the wood fibers make the whole bit bounce between the channel walls. Once the bit has some clearance it works just fine.

Anyway, this is a test piece, intended to be a mold for dough rising. 12" long, 3" wide and 3" deep with 3/16" wall (for Scott: yes I am still consuming that cedar fence post).

I am getting quite proficient at making disposable vacuum pods.

https://lh5.googleusercontent.com/-9xf420SfIuo/VH1LgF4xy1I/AAAAAAAAFes/yKzlEvfYHOA/w1341-h853-no/DSC02905.JPG

[scottp55]

Nicest fence post I've seen in a while:)

[chiloquinruss]

Get together with Joe, I believe he might still have some extra post holes to go with those 'fence' posts! :D

Great job and thanks for the tip on the bit I need a bit just like that for an upcoming project.

As far as chatter goes what if you hogged out the piece with a regular end mill and then used the new bit as the 'finish' bit. Would that help with the chatter maybe? Don't know but I will be ordering that bit, thanks. Russ

[bleeth]

Hey Russ-I don't think Gert's been around long enough to know about Joe's special on post holes!

Gert, I would definitely rough most of it out with a different bit as Russ suggests. A Vortex chip breaker end mill would blow you away with what it does on that.

[Burkhardt]

Ha, had to go back to 2008 to find the post holes threads. Too bad such a quality product is no longer available. No wonder with all the Chinese imports nowadays.

But it is true I did not have not CNC on my mind back then.

As for my chattering problem, hogging out first with a roughing pass is surely a simple solution. I just liked the method to directly finish cut at full 3" depth because it saves me a tool change and a lot of machine time. Right now I can machine the inside and outside of this mold with barely visible tool marks (0.02" stepover) in less than 50 minutes.

I have now changed the program with a weird double waterline strategy where on each z-level of such deep slots the bit first machines a loop at a small distance away from the intended surface to create clearance Then it does another loop on the target path. The clearance will hopefully avoid the slot wall bouncing. Of course that also takes longer but is only required for the mostly vertical wall sections. I will try that next couple of days.

[Burkhardt]

The slot clearance method did the trick. I made another bowl from a Juniper/Red cedar blank and that came out very clean. You may see I am working on Christmas presents, too.

This time I went with only 0.008" stepover which made for a quite long machine time (about 90 minutes each side) but now I just need to buff it with some 600 grit or x-fine steel wool. Otherwise it is good to finish as it comes from the machine. You have to look with a magnifier to see the bit traces. Wall thickness is only 3/16" and aligning inside with outside cut took me a while to figure out. The size is 8" diameter x 2.8" deep.

Inside cut (1/2" 4-flute ballnose, 3ips, 9000 rpm)
https://lh4.googleusercontent.com/-qp8KkZgm6zo/VIFF1CNcntI/AAAAAAAAFe8/h9vnlFVU0i0/w1286-h853-no/InsideCut.jpg

Outside cut (same bit and speed)
https://lh4.googleusercontent.com/-JMhHFUCaqcc/VIFF3A0KoNI/AAAAAAAAFfE/6WcTK0ETACo/w1288-h853-no/OutsideCut.jpg

[scottp55]

Hey G. , Looks like you have it dialed in! :)
Virtual "No Sand" finish is perfect cut in my book and maybe others in non-production shops.
Thinned CA i see in Pic? Was it soft or cracked?
REALLY like how you're making your own Excelsior for a display pillow/closet sachet! :)
scott

[Burkhardt]

...Thinned CA i see in Pic? ...

The CA glue is indeed to seal some cracks. If not sealed, they tend to tear out and are difficult to fix after finish machining.

Also for the machining of the outside, especially when making such thin walls, all cracks and knots must be sealed very well or you will lose vacuum immediately and send the piece flying. In this case I even oil finished the inside first for additional leakage reduction. In spite of the large surface and thin wall I could keep 24" vacuum cutting the outside until the end.

Did you start your vacuum experiments already? I recommend a large vacuum gage in clear view as almost more important than the pump. Then you can see if something bad starts happening and turn off the machine before you ruin the work piece. I am even considering a vacuum switch connected to the E-stop but on my machine the E-stop stops hard and does not decelerate (as it should) and will lose steps. So got to think about how to put the machine in pause mode remotely.

[Burkhardt]

Finished (danish oil and carnauba). Still need to make another 3 or 4 bowls for Christmas.

Yes, I cheated. I buffed and waxed it on the lathe.....

https://lh5.googleusercontent.com/-NNU-G0G5fk8/VIKKDa--jJI/AAAAAAAAFfU/oiFJQfG-ZVo/w1106-h853-no/DSC02926.JPG

[scottp55]

Came out beautiful G. , I'm sure they'll be treasured:)
Used up the last of my carnauba pellets(was adding 10% by weight to beeswax) so researched Mothers, but didn't like they didn't list exact petroleum distillates used, so will probably stick with mineral oil and D-Limonene.
No on Vac, keeps getting sidelined.(spent 2 hrs with Dad yesterday trying to convince him that "deep frying" Maple in 350F paraffin was a BAD idea, and much better to micro torch Maple for effect he wants, and THEN do the 170F paraffin dip/soak I've been using for buttons- Oh, test buttons soaking in water for last 24 hours- then on to Woolite washing tests).
Thanks for Gauge tip , only a 2" dial, but made me rethink placement and will now mount gauge/main valve on top of Crate next to E-stop/spindle interlock key using a mounting block and the Crates connection bolts(1 Allen key bolt to mount/remove) as it will also help keep vac lines away from the Y-rail. Renesting so waste will be held as well as buttons to prevent bit chatter when waste loosens up.Hooking Pump into UPS but running out of "switched" outlets.
Getting good tips as I get closer(Thanks David and George).
Nice versatile program from "eggs" to "bowls" :) Congrats!!
scott

[Burkhardt]

...... researched Mothers, but didn't like they didn't list exact petroleum distillates .....

MSDS Sheet Here (http://apkgroup.com/msds/English/Mothers%20Wax%20%28MOT%29/35750%2810-027-2011%29.pdf). It is written about as harmless as I have seen an msds. I have no concern using it for bowls in occasional contact with fruit or bread. There is anyway only a very thin film on the wood and the naphtene solvent will evaporate immediately. But I would not use it for spoons or similar that people lick off.

Making your own wax is probably preferable. That paste was just simpler for me.

[scottp55]

G. , Didn't mean to sound down on it! Reviews gave it absolute top rank(about what I expected from something you probably use on your "Toy" :) ) and only negatives I saw was that it was too "Old School" and required too much "elbow Grease" to remove when they put it on too thick, and not as easy to use as those with more "gunk" in them. Nowhere near a black mark as far as I'm concerned.
Dad made 2 sales calls this trip, "hoighty-toighty" upscale shops whose customers go so far as to raise their own sheep/llamas/alpacas etc.. Their eyes glazed over on "hot dipped paraffin""mineral oil/paraffin wood butter", but when he dragged out the Celtics I buffed out Tuesday AM and said "Maine beeswax/food grade Coconut Oil/Lemon Oil wood butter" Their eyes lit back up and one asked if he sold THAT :) Hey give the customer what they want. Did find Carnauba at $57 for 8.8 pounds. Probably good sales point for those who know their waxes.
Bowls really do look great!! :)

[myxpykalix]

G,
did you cut that bowl on a lathe or on your bot? I gave up bowl turning because of the arthritis in my neck and shoulders. That looks beauitiful:D

[Burkhardt]

G,
did you cut that bowl on a lathe or on your bot? I gave up bowl turning because of the arthritis in my neck and shoulders. That looks beauitiful:D

That is CNC cut (see previous page for some pics during machining). But I did use a vacuum chuck on the lathe to sand 600&1000 grit and buff the oil/wax finish. It is impossible to do that by hand with same quality.

I stopped wood turning also several years ago, partly because of tendonitis and partly because I just ran out of talent.

I was surprised how well this juniper (I believe it is the same as aromatic red cedar) can be polished. After 1000 grit and 0000 steel wool it had a nice shine already.

[Burkhardt]

Faboulous having a few days off over the holidays. I even finished my Christmas present bowls on time. Here is the final yield:

- I made another bowl from juniper like the one in the earlier posts

- Baguette bread tray 24" x 3" from maple, lightly stained:
https://lh3.googleusercontent.com/-LfR0gCgXGBY/VKcQMR_n9yI/AAAAAAAAFhc/nqbVRCZk69Y/w1191-h853-no/DSC02969.JPG

- Myrtle bowl 8" . Looks great after lot of sanding but not a good wood to machine, very stringy and lot of tiny tearout.
https://lh5.googleusercontent.com/-9ZNjQaWAd4Y/VKcQI_JFAII/AAAAAAAAFhM/jZZNZvTKrBQ/w1135-h853-no/DSC02965.JPG

https://lh4.googleusercontent.com/-aw__VsWPPtM/VKcQKWH8NnI/AAAAAAAAFhU/QkU8yEH_PpY/w1115-h853-no/DSC02968.JPG

- small 5" bowl from very checked mulberry sapwood. It shows that even a piece of firewood can make a respectable bowl.
https://lh6.googleusercontent.com/-22XQgIuWg2U/VKcQHUSwOwI/AAAAAAAAFhE/egZn3c_am_g/w1135-h853-no/DSC02959.JPG

[scottp55]

They're all Great G, But the Myrtle was definitely worth the work!
See striped and burl maple all the time in peoples wood piles:( Enough to drive a guy nuts:)

[Tim Lucas]

beautiful !!! Did you write the tool path or are you using Aspire?

[Burkhardt]

beautiful !!! Did you write the tool path or are you using Aspire?

No Aspire. This was made with special tool path generating software. Actually the tool path is a single contiguous spiral from top to center/bottom. This is the fastest and smoothest way to cut. It will also make tool paths for conforming vacuum chucking plates.

[angel and the bear]

awesome work, love your avatar too! thanks for sharing, can't wait to try a version of this! :)