I didnt realize the ideal process is to run one side through a joiner and use that freshly joined side as the base and run the other side into the planer. Or do you need to plan the joined side as well after?
If your joiner is in good working order, thereâs no need to plane a joined side. Itâs already been made flat. Technically, a joiner does two things, it makes one side flat, and it makes that flat side perpendicular to the side/edge riding the fence. The two things a planer does is make one face flat, and makes that face parallel to the opposite face that itâs riding on (or the effective âfaceâ). But since the planer exerts a fair amount of force on the board, and can uncup a board just by its clamping force, itâs better to join one face first, getting it to a âtruerâ flat, before using that flat side as a reference for your planer to flatten the other face.
edit: The usual use for the âsquaringâ function of a joiner is to flatten a face of the board, then put that flat face up on the fence, and get the edges square to the face. At that point, youâd want to use your planer to flatten the opposite face, but your edges are now square, and you can join multiple boards to make a wider board⌠
Actually, I think thatâs backwards. The primary use of a joiner is to get an edge perpendicular to a face, but you can use it to flatten a board.
What Iâve seen is:
- Flatten a big side on the joiner.
- Flatten on edge on the joiner, keeping the joined side against the fence.
- Use the table saw to cut the other edge, so they are parallel. The joiner wonât make a parallel edge if there is any difference. This is where you get your final width
- Send the other face through the planer. This is where you get your final thickness.
- Use a chop saw or crosscut sled on the table saw to cut the ends.
The more wood you take off in each step, the more likely the board will move when going through these operations, so you have to get within 1/4" first by rough cutting.
Itâs all a huge process. Wood is a natural material and doing precision work is always a miracle.
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Thatâs why we break it down, and reconstruct it into engineered material (laminated beams, MDF, etc) to do amazing things with it!
Thats the one thing im curious about messing with except I dont feel like buying a monster sheet of it. Seems like the dust sucks but everything else about MDF is pretty good.
MDF is also hard on bits. Keep spares and donât use bits for MDF on regular wood afterwards.
MDF is good for milling and painting. It keeps crisp edges.
Baltic Birch (not the home depot kind) is really nice. Void free, and cuts like sugar cookie dough. I like the look of the edges after finish too. But itâs not for everybody.
I didnât know home depot carried anything similar to baltic birch. I do know itâs better than the crap lowes carries.
They sell âbirch plywoodâ here, but it has the same terrible glue and voids in the middle layers.
I think you really need a full fledged lumber yard to get honest to goodness Baltic Birch plywood. Otherwise itâs the same garbage with a nicer outer skin and a swipe by a sander.
One of the things I love about the forums here is that they are made up of a mix of people; some having fantastic backgrounds and knowledge of Electronics, Programming, 3D Printing, Woodworking, Metal Working, CNC backgrounds, etc. Each is able to give Great advice and recommendations.
Getting into a new hobby, or hobby business also means being reeducated, and educating yourself in all the topics needed. At least to a level to make the hobby enjoyable.
It also means that you MUST learn about the medium you are working in. In this case it is wood. Wood being cut, egraved, carved by a small router guided by motors and a computer.
The CNC only knows what the program tells it. Nothing more, nothing less. It doesnât know why something isnât turning out right. Thatâs why we all have turned to the forum is to get help.
If you are planning to work with wood as your medium, then you need to learn as much about the various woods as possible.
You stated you are machining Particle Board flat to use as a spoil board. NOT A GOOD IDEA!!! Particle board will kill whatever cutting bit you use on it very fast. Itâs nothing more than compressed wood chips/sawdust/powder held together with hard resins. Those resins will not only dull the cutting edge very fast, but will nick the cutting edges, as well as cause excessive heat and burning a cutting edge.
You said youâre using Pine because it is cheap, mentioning that the oak worked better. Pine is actually one of the hardest woods to work with. Since it is soft, the sags (compresses) when struck but a cutting edge, which causes tearing, and dulling of the cutting edge. Also the sap in pine never dries or goes away⌠NEVER! That sap builds up in the cutters and causes excessive heat build up, dulls the cutting edge, and MUST be cleaned off the tool after EVERY use. That of start buying your router bits by the dozens.
All wood contain âStored Energyâ in the form of tension. Commercially sold Pine from the big box stores, and lumber yards is rushed through the mills without allowing the wood to stabilize, and then rushed through the kiln, tossed on a truck and delivered straight to the stores and lumber yards. You look over the board at the store and say this looks pretty nice, buy it and then when you get it home, cut it. When you cut it, you have just released some of that energy/tension and restructured the remaining. Then the wood you just cut starts to bend, twist, bow, cup, etc. over the next couple of days or so. There is no set amount that this happens in, and varies from species to species⌠but Pine is the worse for this.
Woodworker go through the following steps when working all types of wood: These steps can take days or even weeks to prep to wood.
- Step 1: Place the wood in your shop and let it climitize for a day or more⌠gets the wood to the same temperature and about the same humidity as your shop.
- Step 2: Cut the wood to a working size - longer and wider than needed ⌠this is needed for proper machining. Let the wood sit for a minimum of 24 hrs.
- Step 3: Run the wood over a Jointer to create 1 flat side, and 1 flat edge. DO NOT try jointing both sides flat, as it will result in a wedge shape!!! Jeff was 100 percent correct! Let the wood sit for a minimum of 24 hours. Then inspect to see if it has warped (which is very common when using Pine), as jointing releases a lot of tension in the wood. If needed repeat this step.
- Step 4: Run the wood through a planner (or drum sander if you have one) taking very small pass cuts at a time. Deep cuts is not only had on the equipment, but releases a lot of tension at a time. Let the wood set for at least 24 hours.
- Step 5: Cut and machine to final size.
I would not advise trying to machine any type of pocket into any type of plywood, particle board, or hardboard to use as a spoil board. All plywood materials, regardless of their quality are glued together, and will play havoc with a cutting edge. I recommend using a good quality MDF for a spoilboard, and do not try to cut a pocket in it either. MDF is cheap, Hard, and the is the flattest sheet goods you can use, just remember to keep it dry, and well supported.
One other thing you need to realize about cnc cutting/carving ⌠the MPCNC and the Lowrider are feather weights⌠they are using small âTrimâ routers, not CNC spindles, or large routers. What this means is that when you are using them you do not have the tactile feel that a woodworker has when he/she is doing it by hand. Therefore you are get some errors because pine is soft and hard. The rings (or grain) is hard, while the wood in between them is much softer. Like I said, the CNC machine doesnât feel this and therefore doesnât adjust to it. Using a dull router bit/cutter or a large one can cause the bit/cutter to bounce off when it encounters the hard grain.
Hardwoods have a far more evenly hardness, and since the wood is harder, it also resists being compressed by the bit/cutter, and cut rather than be torn away.
Yes Pine is cheap, but can cost far more in the end. Check online for small local lumber mills, or hobby lumber mills you will be able to get better wood through them at better prices than the lumber yards or big box stores. Note: The drawback is that many of the small mills do not have kilns.
A not on Baltic Birch⌠What Home Depot sells is not a true Baltic Birch. And yes it is Shit. A lot of "real lumber yards) are NOT selling true Baltic Birch either. Basic rule⌠if it is in a 4x8 sheet, it is not true baltic birch. What a lot of the lumber yards are selling is China - Baltic Birch in 4x8 sheets. Unlike the high dollar baltic birch, China Baltic Birch might have some small voids. Normally close to the edges. China Baltic Birch is a true Baltic Birch, without the love and attention of the baltic birch from Europe. Russia is also starting to import more Russian Baltic Birch and it too is available in 4x8 sheets. The main thing about both the Russian and Chinese Baltic Birch is that the a lot of it is poorly glued together and tends to delaminate.
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Excellent tips so much info to take in. Ill keep that info in mind about killing my bits on soft wood and particle boards. I already surfaced my spoil board but once that thing is swiss cheese ill switch to MDF.
As far as a good wood to work with (avoiding pine) thatâs easily machinable that wont break the bank or kill bits prematurely do you have any suggestions? (I know I know I want it all lol)
This is all great advice, but there is a lot of room for working with pine and particle board. Itâs definitely possible to get a lot of projects done in these materials without a lot of stress.
The milling process is also very good information, but again, doesnât have to be followed on every project.
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I agree with everything youâve said. Just like I agree with all the utensil care advice given in the Smoking Meat thread. I still put my knives in the dishwasher. 
But it is good to know what rules youâre breaking/ignoring/avoiding, and what the consequences could be, so you can both plan for the eventual failures and maybe even account for the shortcomings ahead of time.
For some of us, perhaps the calculus of materials cost in money and time for both wood and bits, combined with the total amount of pieces actually done is such that pine is a fine choice. But for others, they may find that it is, in fact, worth the extra time and/or money to invest in hardwoods. As for the prep-work milling, I know itâs what should be done, but I donât have the patience for doing it on a project by project basis, and I donât have the space/money/spousal-patience to maintain a cache of prepped material.
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You can also design the piece to tolerate errors.
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Iâve gotten to where I use poplar for a lot of projects. Loweâs sells it in pre-dimensioned sizes like the finished pine. The cost is only a bit more, but it has less knots and tends to warp less.
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I have used okoume plywood (marine plywood) for kayak construction in the past as it has no voids and a finished surface. I would expect it to be very acceptable for a CNC operation. Unfortunately, since I have moved to Pennsylvania, I have not found any local sources.
Poplar is very nice to work very little feathering holds sharp edges and paints well
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