Milling & Machining

[gpounce]

For sure, even with the fairly safe speeds and feeds I have been running with the fogger it was a night and day difference compared to that flood. I think thats the cleanest the mill had been since I got it to I most of my cuts to run well with a nice rooster tail but with the fogger it means sticky chips stuck to everything.

Sticky chips 🤮 flood wins if you can contain the spray, up till you get to the fancy end with air blast. I do a fair bit of fairly slow cutting with large slitting sawa- flood coolant washes chips out of the fine tooth cutters otherwise prone to burning up from packing off.

Cutting dry is great if you can control it. There is some fancy chemistry in the interaction between coolant and workpiece which makes a lot of difference.

 

[psykown]

I am actually a bit excited to mess with the slitting saw for some clipons now that I have an enclosure, I just didnt like that very fast blade spinning around gut height without something between us
I've recently been going down the advances in tooling rabbit hole and man is it eye opening just how much things have changed since WW2 or so with HSS. its crazy the MRR you can get nowadays especially compared to the pre HSS days!

 

[psykown]

That sounds expensive, what machine was it on? I've been keeping up with John Grimsmo the knife guy and I think he said the new spindle on the Kern with instal was $30k

 

[gpounce]

I am actually a bit excited to mess with the slitting saw for some clipons now that I have an enclosure, I just didnt like that very fast blade spinning around gut height without something between us
I've recently been going down the advances in tooling rabbit hole and man is it eye opening just how much things have changed since WW2 or so with HSS. its crazy the MRR you can get nowadays especially compared to the pre HSS days!

Yeah if you push those saws too hard they shatter at something close to the speed of light lol... sometimes you can find fragments.

I can hold .001" straight without a lot of trouble w/ good finishes in steel, aluminum, copper alloys. It helps to make the first few passes as not more than .005 to .010, until the kerf depth is about the same as the teeth, then you can step up the cut depth to not more than twice the thickness of the saw. You can go higher and even try to be studly and do a complete cut in one pass but you have to be careful with the feed, control the rpm, chip evacuation and so on- when chips start packing in the tooth gullets or the saw starts flexing things are starting to go sideways.

I use saws on a lever feed production style horizontal mill, so its hand pressure on the table traverse lever which gives great feedback on how the cutter is doing. Since most arbor/saw combos have some runout that amounts to a cut with some degree of pulsation. When feeding by hand, the tool can push back a bit as the high spot passes thru the cut which relieves tool pressure. When feeding by a screw that high spot is doing most of the work and is at risk of overpressure. Overpressure leads to saw breakage and a wandering kerf, which also promotes tool breakage since it warps the cutter.

Careful setup is the game; minimize the runout, use quite a bit less than the textbook feed and rpm, manage DOC via multiple passes if possible, handle chip evac, use flood if you can, use only sharp saws (don't save the dull ones).

IIRC my largest saw is 6" diam and about 1/32" thick- my thinnest saw is .016". They are super-helpful when sawing pieces of of plate, much less waste, no rough sawing- sometimes I get lucky and saw right to finished size. I use only HSS saws (being a LOT cheaper)- wouldn't mind trying some carbide ones but I'm not optimizing production rate so don't mind if the ops take a bit longer.

 

[gpounce]

Speaking of WWII, coolant through the spindle is great, right up to the point that the transmission is filled with synthetic oil and coolant. I got a main bearing for a souvenir, so it wasn't all bad.

Through coolant is great :) I don't have it on the mill but set up a thru coolant system for the lathe tailstock so I can use thru coolant drills. They are $$$ for large sizes so I only have smaller ones but it is effective. Somewhat easier to arrange thru coolant boring bars of course- so much nicer than constantly fiddling around to get the coolant stream into the part.

 

[psykown]

I feel like there is a pretty big benefit to having some experience with manually running slitting saws and getting an idea of how the feel before trying to get them to run safe in a cnc.

What have been some of your favorite machines to run? I've been looking through all the manufacturers I can think of for that "next step goal" machine, something to work towards for turning this into a career. Obviously depending on how life goes this is pretty fluid but its nice to have a (for me) large goal to aim for.

 

[gpounce]

I think I like running lathes the best, but manually cutting gears on the dividing head and mill is great fun. But I'm a homegamer so its just machines in the garage using 80+yr old methods- mostly I do work as favors for folks. A machinery's handbook, calculator maybe 2d cad is excellent therapy for the software engineering racket at work. There have a few skunkworks projects that I've brought home to do... saves a mountain of the paperwork and related nonsense needed for simple jobs in the facility's shop. Anyhow they aren't really set up for little jobs or somebody's back-of-the-napkin idea.


Prepping to split this bushing lengthwise into 2 halves- this is the production mill I use, the handle seen hanging vertically down at the bottom of the pic rotates a pinion gear that moves the table back and forth. Its suprisingly senstive and effective. There is a halfnut assembly that can be fit for handwheel feed of the X axis, I use that fairly often too.

A freebie job for a friend of mine- this is the glass/metal base for a bigscreen TV that had the wrong screws installed so broke the plastic anchors out of the TV mount piece (seen here with the threaded rods extended up). My fix was to make aluminum bushes that fit into the recessed holes of the base plate, with a t-nuts on the far end, positioned in the hollow of the mount which I then filled with casting plastic. All that jigging drama was to support and align the base in its correct position once the anchors were positioned and the plastic poured. After curing overnight (seen here) the base plate comes off and the threaded rods removed. The rods were greased ahead of time so any plastic leaking in wouldn't glue them in place. TV still in service in their family room standing up to a 13yr old boy and his 9yr old sister- so a good repair ;)

 

[Punkinhead]

Now that I'm retired nearly all my machining is for antique aircraft. I'm tied in with a lot of people who own and restore WWII era planes and it's cool making a part from a hand drawn 70 year old drawing. Last Wednesday I fabricated some custom tools needed to disassemble a 1946 Aeronca L-3 that's being restored as a teaching exercise for children interested in aviation. A few adults and a gaggle of kids just started stripping it in preparation for what will likely be a 2-3 year restoration. I occasionally make parts for more modern planes but my heart is really in the old taildraggers.

 

[BDKW1]

I feel like there is a pretty big benefit to having some experience with manually running slitting saws and getting an idea of how the feel before trying to get them to run safe in a cnc.

Not just slitting saws. Everyone should send a year on a manual machine. It would really help weed out the ones that just don't have it.

 

[psykown]

Big things are happening again! Got the power drawbar finished, installed, and working quite nicely today before work. I think I need to bump the pressure up just a hair more as it drags a litle more than I like on release but otherwise I am quite happy with it! Especially since it cost under $350 or so to make versus OEM Tormach PDB running $1500. Already it's dropped a minute from one program so time to really put it to use

 

[Danno]

What brand home wood mills iis anyone running. We run a wood mizer lt70 at work. About 3000-4000 board feet a day..but big machinery to feed it. I want to make lap siding with precut cants on a rocker jig. Parts and support for a home owners mill is the main question.

 

[Shinyribs]

I've been happy with my Woodland Mills. I got the 27" mill but with the bigger motor since our place is full of oak and hickory. Lap siding attachment was another $500, I think. I haven't installed the attachment yet, but there's YouTube videos showing their operation and it's pretty simple.

I'm a rookie, I don't know what I'm doing and I haven't even tried to fool with figuring board feet. The output of the mill is directly related to my energy levels that day. It'll gnaw through 20" oak slabs damn near as fast as I can push the sled, so any lack of productivity is 100% my fault.

Blade adjustment and whatnot has never moved. A piece of the locking mechanism where you raise and lower the saw head failed and I shot Woodland Mills an email. They'd already updated the part and they sent me two of the new design so I'd have a spare. They build everything in Canada, so parts came in pretty quick.

 

[Danno]

Nice work! Looks good! I have been looking at woodlands, norwood, frontier. The wood mizer lt15 might be an option. But there are a few concerning design details of the lt70. The support isnt great. And the company is very back logged.

Board feet is just width times thickness times length divided by 12. A 16ft 1x6 is 8 board feet. Easy way to get alot of board feet is to cut beams plus the boards to get to the beams. A 12ft 12x12 is 144 board feet. Square beams are ideal. We had a heck of a time trying for 2 perfect 22ft 3x12 Took 6 tries to please a picky customer. A beam would just hide what is inside. So the quoting was changed. And the process slowed down enough to flip the beams/boards around a few times.

Ya I enjoy it but bigger production has big problems. A simple mill like a lt15 can produce alot of product. I think the woodlands would produce more siding than I could ever use. And handle beams at a slower rate.

 

[Shinyribs]

I watched a lot of videos on different designs and I remember correctly the wood mizer had the overhang design that you could see bouncing in the videos. I didn't care for that, but the lumber looked fine, so who am I to say 😁 I couldn't find a bad thing said about Woodland Mills and the price was considerably cheaper so I went with that.

27" mill with 16' of track and the 14hp motor. Pull start because I don't need another battery around here. Lap siding attachment, blade sharpener ( it's swedish built and very nice) and a spare parts kit with all the bearings, belts, guide blocks,etc came up to $5,600 shipped to my door. I couldn't justify another $1,000 to step up to the 30" mill, and honestly I don't want to fool with logs that big anyway. I'm just having fun with the thing and don't have equipment to move huge logs anyway.

When you get the sharpener from woodland it has a cam to match the profile of the Lenox blades they sell, but they're twice the price of other blades and the tooth profile isn't optimal for hardwood. I ordered a box of ten Ripper 37 blades for $120 and reprofiled the sharpener cam to suit. The Lenox blade that came with the mill wandered in oak and threw dust. The Ripper 37's throw chips and don't bog the engine down.

I try to keep the logs clean and get through about 10 logs before I need to change blades. All my blades are on their third sharpening now and holding up will. No signs of cracking and haven't snapped or thrown a blade yet.

 

[Danno]

The lt70 has a one side rail. This has caused guide wheel problems. But the alarming part is the wire routing was zip tied tight where every wire has stress. We went into limp mode and it shut the whole operation down. The yanmar service tech has been there twice and it happened again this morning. Saving grace was I found the issue. Plactic wire loom through an uninsulated p clamp by the turbo grounded 2 of the regen wires. It would be nice to have simple mill controls. The lt seems to take a crap only when we have big cypress orders.

 

[Shinyribs]

Yeah, that's annoying. Woodland sells an electric motor version that I looked in to. Makes a lot of sense for a stationary mill, until you start thinking about cable routing. I'm glad to have a basic machine. Zero wiring on the Woodland. The hour meter runs off vibration. Throttle grip and centrifugal clutch. Let's go.

But I see the videos of the fancy mills with log turners and remote control dogs. Those are slick.

 

[Danno]

Even the log turning hydros have ecm. But yes lifting, a rolling chain, clamping, leveling all through joysticks and a tft screen. Much of this could be added to any machine with manual hydros. There is nothing special about the hydro valve block. Just magnetic poppet valves.. Gets kinda crazy when the end of a butt weighs 100lbs of pounds on a 16ft oak slab with a thin center. The hydraulics kick that piece fast for whoever wants it! I prefer cypress..but wet cypress is heavy too. There is definitely a level of excitement with the weight, length and cycle time. Awesome when it runs smooth. We have knocked out big beams in under 4 minute cycles while edging and stick/stacked all the edged live edges.

 

[BDKW1]

Started out at about 700#

2" Seco insert mill. 1280rpm .0075fpt .150doc Took about 2 hours to rough out.

Monday we'll see how much it warped. There's. 060 on the sides and .250 on the hieght. Hopefully it's enough.

 

[gpounce]

Man that sounds a sweaty smokey job 150 thou no join steel.. what material- chips look great

 

[BDKW1]

A36 plate. The flame cut edges are hard on inserts. It also puts a lot of stress into the bar. It had about 1/8" of bow from the cutting. Once you cut the skin off it will move. I would have preffered to have it normalized, but that wasn't in the budget apparently.