Just about two years ago, I stopped using my dado set for my table saw in lieu of my router and an “undersized” 3/4″ bit. Faster set-up, cleaner cuts, blue skies for miles!
Now, the plywood industry has struck again! Thinner veneer=thinner plywood!
I’m back to my dado set, eagerly awaiting the next “undersized” router bit to show up on the market!
Pretty soon I’ll be looking around for an “oversized” 5/8″ bit!
Replies
You have noticed it too, have you.
I was working with a couple of pieces of birch plywood yesterday. I had them stuck together with carpet tape while I cut them so they would be identical. When I pried them apart, the tape actually pulled a piece of veneer off. If it gets any thinner we'll be able to see through it!
Surely you can get your router bits ground to whatever size you like.
I would go to the knife makers for spindle mouders.
benchdog, cut a 12 mm groove, trench, dado, housing et al in the female part. Create a shy 12 mm tongue on the matching edge of the male part-- you can leave it a tad fat and do a final fit with a skimm or two using a shoulder plane if you're pernickety.
One extra step admittedly, but still quick and a stronger joint anyway, and you don't have to worry about the exact thickness of your man-made board. I rattle these joints out in n short order and seldom find any use for a full housing, dado or groove. Slainte.
Sgian,
Would this still be strong enough for a full-size book case? You are saying, for example, that a 0.47" (12mm) plywood tongue can hold a 35"-long shelf full of books?I'm not doubting you, I just want to confirm that we're talking about the same thing here. If so, I'll switch to this system in a moment. Beats trying to match the dado to the thickness of the plywood!
Edited 2/10/2005 12:19 pm ET by Matthew Schenker
Matthew, if you put the tongue worked on the end of the shelf to the bottom you effectively have the whole thickness of the ply supporting the weight (books) on the top face.
If you put the tongue to the top then you should probably consider that only the thickness of the tongue is carrying the weight. but to set against that you also have a larger gluing surface and a mechanically better joint because you have more returns and interlocking angles.
It does perhaps take a little longer to work, but you're no longer a slave to finding the right diameter router bit or shimming dado blades to suit the materials thickness. Mostly I cut the joint with a router, straight bit and T square housing (dado) jig which registers off the front edge for the housing. To cut the tongues on the end of the shelf I use a router, straight bit and router side fence (edge guide.)
I know the joint as a tongue and groove if worked with the grain, or tongue and housing (US dado) if worked across the grain. Slainte.RJFurniture
Sgian,
I would put the tongue on the BOTTOM of the shelf. In addition to the reasons you gave, the approximately 1/8" thickness above the tongue conceals the seam where the dado and shelf meet up.It's always good to get your opinion on these matters. It really helps someone like me to gain confidence that a technique I am considering is the proper way to do things!
Edited 2/10/2005 12:54 pm ET by Matthew Schenker
As an addendum to my post 8 in this thread Matthew, here's another configuration. Run a groove (along the grain) or housing or dado (across the grain) at anywhere between 6 and 9 mm (1/4"-- 3/8") and make the tongue on the end of the male part to suit.
This works well for cabinets or bookcases with shelves. You can cut all the shelves the same length as the base and the carcase top and work exactly the same joint for every shelf end and top and base. you just need to orientate the housing at either end of the sides so that the tongues worked at the ends of the base and top face towards the centre of the sides.
This way you leave enough meat at the end of each side beyond the housing to be strong enough that it won't simply break off during assembly and in service. Slainte.RJFurniture
Sgian,
Just to make sure we're talking about the same thing here, I created a quick file with the two joinery suggestions you gave.Tell me if I have interpreted your suggestions correctly.Thanks,
Matthew
Mattew, first one, yes- second image, no.
In both cases the tongue should be as in your first drawing-- an extension of one face with a rebate worked from the opposite face to create the tongue thickness.
It's just a case of adjusting the rebate (rabbet) depth to create the appropriate tongue thickness, e.g., 1/2", 3/8", 5/16", 1/4", etc..
The tongue is worked to match a groove or housing routed by a standard router bit, and the measurements I listed above are standard router bit diameters. You could just as easily use convenient dado blade stacks to form the groove or housing as use a router bit. Slainte.RJFurniture
Eeek, I eagerly downloaded the attachment and opened it up. This is all I got:
Book Case Possibility #1: single-shoulder joint (front view):
Book Case Possibility #2 (front view):
Color me sad. Wha' happened? I tried opening it with WordPad, no luck. IE -- didn't open. Help!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)Another proud member of the "I Rocked With ToolDoc Club" .... :>)
forestgirl,
It's a Word 97 file. I think if you save it to disk then open it in Microsoft Word, it should be visible.If you still can't see it, let me know and I'll e-mail the file to you.It looks like only the first one (Book Case Possibility #1) is worth looking at.
Ahhhh, that explains it. I'll put it on my old computer, which is the only one that currently has Word on it. Hmmmm, that reminds me, now that I have all those glitches fixed on this computer, it's probably safe to go ahead and install Word!forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl ;-)Another proud member of the "I Rocked With ToolDoc Club" .... :>)
You lrft the s out of persnickety. Definitely from Canada.
Nah, not a Canuck, David. other side of the pond. Slainte.RJFurniture
The joint Sgian's talking about is called a single shoulder joint in this country, the USA. It's the best way to deal with plywood to be sure.
All I would add to Sgian's instructions are that if possible index your cut on the edge of the plywood from the face that will be retained. This way the tongue left will be precisely the right thickness and variations in the thickness of the sheet will be taken up in the rabbeted side. A shaper is the best tool for this but there are top bearing router bits that will accomplish this same task.
Lee
Sgian had me going there with his millimeter talk! : )
I've tried all joinery possible with plywood, and you're correct that it's the best way to join it, but time consuming.
I'm lamenting on the plywood industry, just how thin are they willing to go?
"I've tried all joinery possible with plywood, and you're correct that it's the best way to join it, but time consuming."Benchdog,I agree that thinner veneers and unorthodox plywood thicknesses are a PITA. That being said, however, the rabbet-dado joint to which Sgian refers isn't all that time-consuming - once you finish making test cuts.Whether you're using a stacking dado set or a router, test pieces are required; it doesn't matter much if you're milling a single dado or a dado and corresponding rabbeted tongue. That's probably one of the reasons I prefer to use a rabbet-dado or lock rabbet for production drawer making (when the revenue per drawer isn't high enough to justify dovetails).Something to consider,-Jazzdogg-
Whether you think you can, or you think you can't, you're right.
I use lock rabbets for drawers as well, for the exact same reasons.
On carcass construction I prefer to use a full width dado, simply because I can't stand to see any seams. A tight fitting dado will also conseal any fine tear-out from cross cutting, which saves some time from scoring the pieces.
AH well, If you lot would convert to mm there would be no such thing as thin ply. 1/2" (nominal 12.7mm) would simply be 12mm - problem solved.
Actually, I learned the craft in mm from a Portugese woodworker. Since then though, it just makes more sense to use inches because everything here is labeled that way.
When in Rome, do as the Romans!
P.S. I could easely convert to mm, but try convinsing some architects to switch over!
It was supposed to be very tounge in cheek. We (Aust) converted to metric in 1966, except....
Some indutries recieved exemptions and changeover periods. I have just bought a house built in 1973 and extended in 1986. The original plans are in Imperial measure, the extension, drawn on the same plan is metric. So I have both systems on the same plan sheet to deal with issues such as a new heating system.
We also had the time when all of the dowell making machines wore out at the end of the 80's. I have 12, 12.7, & 13mm bits to deal with nominal 1/2" dowells produced since then.
Same as you, when you play in either this or leather work you rely heavily on the size of the US market for supplies and it is easier to change rulers than do the conversions.
Why use plywood at all? Nice veneered plywood is easily $45 dollars a sheet.; while I buy solid wood (Say white oak) for $25.60 for 32 bd.ft. (4'x8'=32 sq.ft.) I can get hickory birch, and a lot of other hardwoods for the same price..
Now granted that's rough and green and at the mill price but why not sppend a feww hundred dollars up front buy too much , dry it and start to save money?
If you use a thousand bd. ft. in a year buy two thousand bd.ft. dry it and plne it to the thickness you want and be done with it.
2000 bd.;ft of hardwood, cost today $1600.00 , 2000 bd.ft. of plywood @ $45 a sheet Cost $2812.50, saving you over $1200 dollars which should easliy pay for a planer with enough left over to pay any interest charge on your credit card.
The next year when you buy the wood you'll save even more..
Labor hours to process that much lumber into panels would easily negate any savings. Not everyone has access to lumber as cheaply as you do frenchy but you do love to brag about it don't you. The fact is that plywood is often a better material to use especially when one doesn't want to be concerned with wood movement or wants consistent bookmatched or slipmatched panels.Tom
Douglasville, GA
"Why use plywood at all?" Frenchy,In a word, stability: plywood is inherently more stable than a cross-grain assembly of solid wood.Yeah, there are plenty of times I've preferred to use solid wood for various projects, but shelves - with their grain perpendicular to the sides of the case - isn't one of them.To me it's a trade-off between the issues endemic to solid wood's expansion and contraction (not to mention the extra time required for machining rough wood, and the stability and convenience of sheet goods.My $0.02-Jazzdogg-
Whether you think you can, or you think you can't, you're right.
Look to our recent past for methods to deal with woods changing nature.. There are countless methods to deal with that issue and still result in "fine woodworking"
As for the extra time involved, don't you need to spend time to put a banding on the edge of plywood to deal with the "look" of plywood? In additon the risk of dealing with Plys of various thickness are eliminated.; Finally imagine a ding or dent of significant depth.; you cannot possibly deal with that by sanding.;. you'll go thru the ply , whereas if you spread the dent/ ding removeal over a broad enough area on solid wood it will effectively disapear..
Frenchy-
Good job on the analysis. I think you forgot a few things.
1. You assume that all the hardwood lumber will be usable. I think you need to throw at least 20% more lumber into the equation to account for wood actually yielded.
2. I know many, many hobbist woodworkers like to say that there time is free. I am also a hobbist woodworker, but my time is not free. In fact it may the most valuable element in the equation. Let' conservatively say that time (my time is worth $100/hour)
3. As others have pointed out-- plywood is a great product because it is dimensionally stable and as I will show is a cost effective material.
Using my additions to your first equation:
$.80 X40bd ft = $32.00 for the material for a solid piece of 8X4
40bd ft = the total amount of lumber needed (20-25% more than you counted for) .80/bdft for the lumber. By the way I would love to know where you buy any hardwood for .80 / bdft.
Now for the labor time
I estimate it would take about 4 hours to dimension and glue the lumber. That comes to 4hrs X $100 = $400. Plus the lag time for it to dry= another 6-10 hours which I will not put any labor rate on since no physcal man hours are being sent.
IN TOTAL a 4x8 sheet of hardwood equals $400 time plus$32.00 for material bringing the total to $432.00 in total for a piece of hardwood 4x8.
Thanks--but I will stick with plywood.
BTW--This has been fun. and I hope you do not take me too seriously. I see your point, hope you see mine too.
Thanks for playing,
Mark
Thank you,
The Great Marko
marko,
I agree with you. My woodworking is a hybrid of hobby/professional, with growing emphasis on professional. In recent years, I have become ever more attuned to the value of time spent on a project. I have learned, the hard way, not to underestimate time. For the first few projects I was hired for, I would name a date that seemed manageable. For example, I would say three weeks for a built-in, because that's what I figured it took me in my own home. But doing a built-in for a client is not the same as doing it for myself. In your own home, you can wander over and do a little here, a little there. If the project has time over-runs, you don't mind that much. But when you're working in someone else's home, you don't have these luxuries.There is nothing more stressful for me than falling behind on a job I am doing for a client. For any bookcases and built-ins, I use plywood as much as possible. As you know, built-ins usually involve a lot of on-site finish carpentry. Plywood allows me to calculate with greater accuracy the time for construction, leaving more time to fiddle with finish work on-site and still get the project done according to the proposed time frame.Of course, I use hardwood for lots of projects. Someone asked me to make a set of nested tables, and I built a kitchen table for someone else. For these, maple was a perfect choice.So I guess the distinction is whether the project is entirely shop-built (furniture) or has a lot of on-site components (built-ins).
Edited 2/10/2005 3:01 pm ET by Matthew Schenker
Matt:
I am with you. Plywood is a viable product. Those do not feel that is a product worthy of fine furniture or craftsman pieces have their right to feel that way. But I feel that plywood vs. solild wood is alot like the debate between power tools and hand tools. Both can can get the job done. Using solid wood and hand tools will product wonderful results but will take a considerable amount of time.
Personally I am an advocate of using ply (other sheet good like MDO, particleboard and even MDF) for particular projects. But I also love using hardwoods for a majoirty of my work. Just like I use a good mix of both power tools and hand tools.
The moral of the story is "Use a balance of modern day technology coupled with strong traditonal methods and you can not go wrong in producing high quality, hand crafted pieces.
Thanks for letting me ramble.
MarkThank you,
The Great Marko
Marko,
I do see your point, but to me there is something inheritly superior to solid wood over plywood, particle board or MDF..
I honestly don't expect a plywood anything to ever be considered as fine as it's solid counterpart*.. Maybe it's decades of dealing with antiques made from solid wood maybe it's just snobery on my part anmd maybe it's just because I'm really a cheap tightwad and buying soming that I feel is superior for a lower cost is a bargin that I can't pass up..
* I don't want you to assume that I think I'm better than you are.; Let me say that my best efforts with plywood and my best efforts with solid wood will make a piece made from solid wood superior.
I'm building a timberframe house because I feel that a timberframe is somehow superior to it's plywood counterpart..
Frenchy:
I admire your apreciation for hardwood. Of course I do not think that you think that you better than me or anyone else.
I found your post to be great. It just made me think and then one thing led to another and here we are.
Good chatting with you.Thank you,
The Great Marko
Darn! No arguement, <G>: sigh!
Personally I get sick of solid wood for a while when it starts moving around and acting up, then I get sick of plywood because it's so ridiculously thin and easy to damage, both when I'm building and afterward when it's being used. No perfect answer. I do think probably for shelving solid wood is better. It's stronger and shelves tend to get a lot of abuse. Any movement doesn't matter too much on a shelf. Also, not too much time or difficulty gluing up a "panel" to serve as a shelf.
antiques made from solid wood ..
I agree BUT they got wood in nice BIG sizes REALLY cheep back then!
I'm building a timberframe house
God I wish I had the money to do that.. I lived in one as a kid and in a really old Victorian.. In the Victorian my bedroom was in one of them towers.. How COOL is THAT for a kid!
Actually it's cheaper to build a timberframe than you'd think, the real trick is to find a good source of great wood cheap!
The trick is the need to control wood lust!
Make a jig like a double T-square (Pi sign).
You can register on your baseplate, or use a template guide.
Down one side and back the other with a 3/8" bit.
No tear out on the back cut, and you can adjust to whatever size you want.
Language was invented to ask questions. Answers may be given by grunts and gestures, but questions must be spoken.
Eric Hoffer
Twilight Zone time.
Bought some stain-grade (B) Maple ply from a local supplier a few days ago. Ripped and dimensioned everything as per plans. Set-up and ran dados and rabbets at the usual 23/32". Did a test fit, too narrow. Measured the ply...3/4". Had more plies also. Almost looked like BB ply. Dee Dee Doo Doo....Dee Dee Doo Doo....
You should save those pieces somewhere safe, they're collectors items!!!
And not forgetting,In glue and dust we place our trust.
This forum post is now archived. Commenting has been disabled