Hi gang:
I am considering using 3/4" plywood ripped into 4" strips to build my benchwork framing. I know I want G2S (Good 2 Sides) to minimize slivers etc., but I'm not overly familiar with plywood so I don't know how many plies I should be looking for. What do you suggest?
FYI, the layout will be in an insulated but unheated garage that is fairly well sealed. Cost, within reason, is not an issue. I figure I will need 6 - 4' x 8' sheets. I absolutely will not use OSB!
I spent some time searching Google and the forums but I couldn't find a clear answer as to what is available.
Thanks,
Dave
I'm just a dude with a bad back having a lot of fun with model trains, and finally building a layout!
3/4" plywood is usually 5 ply. The different grades refer to what the finish is on the outside ply. A/A, would be best, anything with B would be it has knots, but they have been filled, anything with C the knots show. ( A/A, A/B, B/B, normally used for concrete forming), A/C, etc., and then you have CDX, which both sides are rough.
Maybe price out 1"x4" which is actually 3/4"x3 1/2" for your framing. This can be bought in different grades, which clear would be the best, with no knots, and grades that have knots, but are tight. 3/4 inch plywood can get pricey. Treated 3/4" plywood is even more expensive.
Mike
EDIT: Just seen you were in Canada, so I have no idea how grades are classified.
Good on both sides really has nothing to do with slivers, but what the actual finish of the top veneer is.
My You Tube
Hi Mike:
I'm pretty sure the grading is the same on both sides of the border. The industry specs for the Canadian stuff are in metric units but I think the classification of the makeup of the plywood is the same.
I'm looking at something with more than five plies. I think it is referred to as cabinet grade or furniture grade but I want to hear others thoughts on it before I spend the money. I believe that the higher grades have better screw holding ability when the screws are are going into the end grain. Somebody correct me on that if I'm wrong please. I do plan on pre-drilling the holes regardless of the material.
I am also going to price 1x4 clear lumber for comparison. I'd love to do the benchwork in poplar but that would definitely be expensive. We have a trim manufacturer close by who sells dimensional poplar wholesale so I will look at that too.
One of the reasons that I am considering plywood is that our model railroad club just happens to be in the back of a cabinetry shop. I haven't approached the owner yet but I'm hoping he could give me a reasonable price on the plywood and the cutting. When I talk to him I want to have at least a basic understanding of what I should be looking at. I have a radial arm saw but ripping 4x8 sheets on it is a pain, and my back won't allow me to handle 3/4 x 4 x 8 sheets anyhow
I second the suggestion of good old fashioned 1x4s, or even 1x3s for that matter. Solid wood is stronger than ply, probably cheaper, and much easier to build with than having to rip 4x8 sheets of plywood dozens of times. Wrestling a 4x8 sheet into a table saw is not fun!
I see you replied while I was typing my reply re: the screwing into end grain, I suspect ply would less terrible at holding screws into endgrain than lumber, but IMO it'd be best not to screw into the endgrain of either, and I don't see why you'd really need to?
3/4" ply is usually 7 ply. You can pay more and get better, but I don't think it's worth it.
I agree that ripping down plywood to make planks is a real pain--just buy planks.
But them we run into quality problems. If you use plywood, the defects average out. If you have a knot in a 1 x 4, you REALLY have a knot.
I buy, on occasion, clear kiln dried fir. Did you know it's REALLY expensive? Especially if it's quarter sawn. It is beautiful sweet wood. EXPENSIVE. And stable. And strong. And EXPENSIVE.
You will probably be happier with 3/4 ply ripped. Really.
While there are some really neat plywoods that some of my buds use, I'm real happy with what is usually called shop grade. It's AC interior. Maybe AD.
I've worked construction most of my life. If that gets any credibility here.
Ed
IMHO, you don't need cabinet grade,A/b would work as well, good side out.
From my experence, I would never trust screw into end grain on plywood, cornor blocks are better,if you must use ply.
As others said I vote for 1x4s. If your picky when you buy, use them up in a reasonable amout of time,don't leave em lay around too long. Once you have em screwed,nailed and/or glued they will stay where you put them
Don't be scare off by knots, if there small and tight, won't hurt anything.
hon30critter One of the reasons that I am considering plywood is that our model railroad club just happens to be in the back of a cabinetry shop. I haven't approached the owner yet but I'm hoping he could give me a reasonable price on the plywood and the cutting. When I talk to him I want to have at least a basic understanding of what I should be looking at. I have a radial arm saw but ripping 4x8 sheets on it is a pain, and my back won't allow me to handle 3/4 x 4 x 8 sheets anyhow Thanks, Dave
You wrote this while I was writing. Just do what he says. The guy's an expert. If you think he's going to screw you over, then don't do it. If he's not, trust him. That simple.
He probably knows more about how to solve your problems than all of us, here. Including me. Oh. Did I say? I've worked construction most of my life. Like 40 years. What would I know?
speedybeeIMO it'd be best not to screw into the endgrain of either, and I don't see why you'd really need to?
How would you suggest attaching pieces at a 90 degree joint without screwing into the end grain of one of the pieces?
hon30critter speedybee IMO it'd be best not to screw into the endgrain of either, and I don't see why you'd really need to? How would you suggest attaching pieces at a 90 degree joint without screwing into the end grain of one of the pieces? I could use corner brackets but that will get real expensive real fast. Dave
speedybee IMO it'd be best not to screw into the endgrain of either, and I don't see why you'd really need to?
How would you suggest attaching pieces at a 90 degree joint without screwing into the end grain of one of the pieces? I could use corner brackets but that will get real expensive real fast.
You use corner blocks. Typically 2 x 2's. See earlier comment by other poster.
There are subtleties beyond this discussion. But that's about it.
1) Buy the best cabinet grade hardwood plywood you can, the more plies the better.
2) If you price it out you will find that even the most expensive plywood is WAY cheaper than individual 1 x 4s. Do the arithmetic yourself. The plywood will be straight and will not warp. I used both plywood and pine 1 x 4s on my last layout. The right answer is plywood. Period.
Disclaimer: This post may contain humor, sarcasm, and/or flatulence.
Michael Mornard
Bringing the North Woods to South Dakota!
Hi Michael:
How did you do your 90 degree joints?
Thanks
UNCLEBUTCHFrom my experence, I would never trust screw into end grain on plywood, cornor blocks are better,if you must use ply.
UNCLEBUTCH:
What would you use for corner blocks? The suggestion was made to use 2x2s but I'd be concerned about them splitting since they would be less than 4" long. I guess if I pre-drill them that would not be an issue?
FWIW, using plywood is not a 'must' but I find the stability factor to be very attractive.
7j43kI've worked construction most of my life. If that gets any credibility here.
Ed:
Your advice is definitely creditable. Thanks for sharing it.
I built a small 4X4 test structure using 3.5" wide 3/4 plywood and fastened the thing together with pocket screws. It went together well and with a little bracing would be dimensionally stable.
When layout constuction commences I plan to use Baltic Birch plywood for the structure, as it is a lot better for pocket screws. Googling around for those kit based layout systems revealed that is the material they often use. The advantage to BB plywood is it has no voids. Regular run of the mill plywood often has another species used as the core, and since it isn't seen, often has voids. Voids don't hold screws.
To rip the plywood I plan to build a cutting table out of two sheets of particle board and use guides to get the right sizes.
Dollar for dollar, plywood is cheaper and more predictable than dimensional lumber.
Do stay away from the big box retailers, their wood isn't that great, and their customers do even more harm when picking though it. Speciality wood suppliers will often have Baltic Birch.
hon30critter How would you suggest attaching pieces at a 90 degree joint without screwing into the end grain of one of the pieces?
It depends on the situation, but I expect you're thinking of how the crossbeams rest on the vertical supports (legs).
The most primitive option is to simply glue+screw their faces together at a right angle so that they form an L shape. Obviously this would offset the crossbeam to the side and so there'd be unfortunate torquing forces on the wood. But considering the relatively light load that is a model train layout I don't think it would even matter... it's not like you're parking a Winnebago on this.
A stronger and more symmetrical solution would have the crossbeam sit on the top of the leg, with their long widths aligned the same way, if that description makes sense. Basically, if viewed from the side, it looks like an upside down "L", with both the crossbeam and the leg showing their 3" or 4" sides. Then on each side of the joint overlap it with short pieces of 1x3 or 1x4, using screw+glue joints.
Face-to-face screw+glue joints of any decent surface area are basically unbreakable... the wood beams themselves will break before the joint.
Another already mentioned method is the corner blocks. Not as strong as the above method IMO when you're attaching a supporting beam to a leg, because the supporting beam has its long side vertical, as in roof rafters.
Re: small pieces of wood splitting when screwed, yes predrilling should take care of that.
But when still concerned about splitting, after you've predrilled your pilot hole, you can also go in very very shallowly with a big drill bit. All you want is the tapered triangular dent in the wood, because wood screws have the same triangular shaped head that forces the wood to split apart as it goes in.
And when really really concerned about splitting, I will also use two of the classic Irwin bar clamps, one on each end of the piece, so that it cannot split. Once the glue has set a bit, the clamps can come off.
I hope this post makes sense... It's 3am.
edit: as was just mentioned, stay away from the likes of home depot if you need decent lumber. I don't know about any lumber supplies in Bradford, as it's not my stomping ground, but if you ever happen to be up in Collingwood, I've never been disappointed with Bill Brown's.
Whether you use expensive plywood, cheap plywood, common boards, select clear boards, old-growth fir, framing 2-by lumber, or whatever . . . if you're connecting with screws, just two words of advice: drill pilot holes. And use star-head screws. The six point bit drives much easier than the four point Philips head bit.
Robert
LINK to SNSR Blog
hon30critterHow would you suggest attaching pieces at a 90 degree joint without screwing into the end grain of one of the pieces?
I bought one of these jigs and the screws made for them
It makes nice pocket holes for screws. Results in a great joint.
I have the right to remain silent. By posting here I have given up that right and accept that anything I say can and will be used as evidence to critique me.
I was spiking down some rail and I couldn't get the spikes in. They would go through the ties, start into the plywood, and then stop and bend. Even trying to get track nails in with a small hammer was a problem. This was strange as I have spiked down rail in other section of my layout without problems. Turns out the older sections of my layout were on plywood with the top layer of wood was about 3/16" thick. The newer section was on plywood that had a top layer about 1/16' or less. The spikes would go into the newer plywood's top layer and stop when it hit the glue layer. Drilling pilot holes for spikes is a pain.
The layer thickness might be a consideration depending how you are attaching things to it.
I have built some tables and benchwork using the ripped plywood to make both the L shaped legs but also the framing and joists (and the table top). I used very ordinary quality 5/8" plywood. I did indeed screw into the exposed end of the plywood both for the legs and the table framing and have had no problems with the joint giving way, even though two of the tables carry a considerable load (an artist's kiln in one case). I was fairly lavish with the screws. Jim Hediger had suggested this technique years ago in MR and it worked fine for me, with no need to go with furniture quality plywood (although I am sure that would LOOK much nicer). I went with what I had on hand. It did however have the virtue of being reasonably flat so maybe I should not call it "very ordinary quality"
Dave Nelson
Use 1x4s, much easier and you can get nice 1x4s for fairly cheap. Knot holes don't always mater as with warp. I bought some 1x4s with a slight warp in 8' but since I needed a 4' and two at 22 1/2", no problem, as far as knots go depends on where they are and the type, if you plan a little many times they end up in the scape.
I am strongly leaning toward using plywood instead of dimensional lumber when I start my next layout, for many reason, but cost and stability are the two big ones.
The nice thing about using 2x2 nailing blocks, evn less than perfect 2x2's can be used (which is good because last time, I could never find even ONE that wasn't twisted to some extent) because you are cutting them down to short lengths. Splitting shouldn;t be a problem - I used the same sort of thing in the legs of my last layout - the legs were 1x3 and 1x4 in an L with a short section of 2x2 at the bottom drilled out for adjustable feet. 2 screws in each of 2 faces, plus a larger hole drilled up along the length and none of them split. I did predrill the holes on the faces, through both the 1x and the 2x2. To speed things up since this next layout will be MUCH larger, I'm considering getting a nail gun and using nails and glue instead of screws to attach the nailing blocks. It's the glue that does the real holding, properly applied it's stronger than the wood. If you've seen any of the newer layout builds on MRVP, they often use a nail gun to hold parts in place after applying glue.
My other option would be to go overboard and make it all out of 2x4s which even the good ones are cheaper than a good 1x4 and the higher quality ones usually have a lot of straight pieces available - it's what I built my new workbench out of. Seems quite overkill though sonsidering most of the new layout will be able to cantilever out from the walls with very few legs.
--Randy
Modeling the Reading Railroad in the 1950's
Visit my web site at www.readingeastpenn.com for construction updates, DCC Info, and more.
Dave,
When I've used the 2x2's, it's not been as short as 4"--more 5" and 6". I don't think it would make much difference. BUT. You absolutely need to drill a pilot hole. I use flat head wood screws, and I have an all-in-one drill that does the true pilot, the clearance for the shank, and the countersink. If you're still worried about the wood splitting (not unreasonable), put a clamp or two across the 2x2 at 90 degrees to help avoid that. I've been known to.
I expect you'll be needing clamps, by the way, to hold things in alignment while you drill. Crooked sucks.
So you're likely to have a whole forest of clamps at a joint as you work. Ugly. But the alternative is worse. And, of course, you remove them when you're done.
I always get kiln dried clear fir. I don't use much, so the cost is minimal. But since it's "flawless", I can just keep chopping off pieces. And it's stable.
I do mostly Free-mo. We build LOTS of modules. The sides and ends are 6" high. The smart move is to add a plywood top, but some people do use foam only. At first. Anyway, all the modules I've seen use plywood sides rather than plank. I use 3/4" AC interior ply, and am happy with it. Other folks use fancier stuff. Baltic birch 13 ply comes to mind.
Another vote for plywood although I don't think cabinet grade is warranted. Common 5 ply hardwood plywood works very well. I used the 3/4" birch sold at big box stores for $30-$40 a sheet for both my benchwork and sub-roadbed. Benchwork has been up for a little over 4 years, sub-roadbed in place for 3 years with no observable change. No track is kinking, no odd gaps have appeared, no warpage or sagging. Even the leftover strips of plywood laying in the shop bin for 3 years are still straight and flat. Can't say that about any of the stick lumber in the same pile.
Plywood grain runs perpendicular to the adjoining layer which makes it much more resistant to dimensional change than solid soft wood. Model trains and scenery don't weigh very much so strength is not a worry. Dimensional stability is the bigger issue. Hardwood plywood wins over stick wood in this measure.
Two important differences between plywood grades are the number and size of voids between the plys and the outer veneer thickness. Often the real difference between a $30 sheet of plywood and a $90 sheet of plywood. Veneer thickness is a cabinetmaker's concern, not important for benchwork. Minimum voids is important for benchwork as it affects screw holding. Better quality plywood has fewer and smaller voids. Stick lumber has no voids but does have knots and sapwood.
I suppose it varies with location, but here the price is pretty much a wash when comparing decent quality 3/4" ripped to 3-1/2" vs 1by clear stick lumber. You do need the ability to rip it yourself. Otherwise, paying someone could make plywood more expensive than stick wood. A table saw is ideal but if you had one you would probably would never have posted the question. A circular saw and a clamped straightedge can be used with success. Common angle steel or aluminum make a good straightedge.
End grain fastening in plywood is horribly weak and tends to distort the plys. Don't bother. The Kreg pocket screws mentioned earlier work very well. Blocking is also a popular and plenty strong method although it encroaches a little on the underside space. You can also use nailing plates and screws if you want easy to modify benchwork.
Stick lumber has the advantage in that you just buy it, cut it to length, and end fasten together. Very easy especially if your woodworking tool selection is limited. Plywood offers stronger straighter construction quality but does require more work and tooling on your part.
Alan
Freelancing the LK&O Railroad
Thanks everyone. Lots of things to consider.
Just to clarify a couple of points, these are the things I decided right from the start to do:
- I have always planned on pre-drilling the holes regardless of the material. I have a double ended bit that does both the drilling with the countersunk hole at the surface, and it holds the screwdriver bit in the other end. Drill the hole, pop the bit out (its magnetic) and turn it 180 degrees, and drive the screw in. It will hold whatever type of screwdriver bit is needed.
- I also intend to glue the joints, again, regardless of material.
- cutting the strips myself is a non-starter. My back won't let me handle the weight of a 3/4 x 4 x 8 sheet of plywood. Doing the benchwork top surface will be bad enough with 1/2" ply. I'm trying to plan things so I can use 4 x 4 sheets on top.
What I haven't decided yet is whether to go with 'L' girder construction or just a flat box style. 'L' girder construction is attractive partly because there are a couple of depressed and elevated areas where 'L' girders with cross beams on top of them might make those areas easier to build.
Anyhow, please keep the suggestions coming.
hon30critter Hi Michael: How did you do your 90 degree joints? Thanks Dave
I used 2x2 s for legs, so I had a lot of 2x2 blocks and they worked fine.I used sheetrock screws rather than wood screws. Have a second drill handy for a pilot hole. You don't need a full size full depth pilot hole, just a 1/16 hole about 1/4" deep was plenty. Sheetrock screws are cheap and are very, very sharp so they're easy to drive.The reason I don't recommend cheap plywood is that if there is a void in the second ply you can crush the outer ply. Ask me how I know.
Also, honesty compels me to admit that the one drawback to plywood is it is MUCH heavier. Not a problem if it's not a portable layout, but you'll want good strong clamps to hold things during building. I found I could use the "quick clamps" with pine but for plywood I needed honest to Pete C-clamps.
5/8" G1S (or "good on one side) plywood is plenty strong, has that nice one side smooth that is mostly knot free, is cheaper and lighter than 3/4", and can be ripped to precisely the same dimensions you need and still be stronger than you need.
For legs, I always use 1X2 spruce. I buy it in the 10' lengths. I place the top end up tight against a corner of the 1X4 frame outer (and by 1X4 I mean spruce or ply...either one), and then 'cap' the top of the leg. This forms an effective and strong joint, although the 1X2 still needs diagonal bracing.
What I mean by cap is that I cut a 4" length of the same 1X2 as the leg, and place it outside the leg so that it is flush across both of them. They both lie 'flat' so to speak. Then I cut another 4" cap that is of 1X4 so that it caps, or covers, both of the snugged items, the leg top and the small block to its outside. I drive several screws, always piloting first in softwoods, to make it all tight and rigid.
You'll find that 5/8" G1S will do everything you need it to do. For what it's worth, on my last layout I built it all out of 1/2" exterior grade plywood, roughish stuff, including all my cookie-cutter roadbed. It worked just fine, including in my large covered helix.
I just did a comparison between the amount of wood required to build 'L' girder benchwork vs a simple box frame and the numbers came out the same. I guess that shouldn't be suprizing since both methods cover the same area. However, the more I think about it, the 'L' girder method seems to be much easier to do and will allow for any elevation changes much better. There is certainly much less cutting and fitting to do and angled joints won't require complex calculations to get the joint to fit properly.
Up until now I couldn't see the advantages of 'L' girder construction but the light has finally dawned! Darn I'm slow sometimes!!! I've been working on this for more than 10 years!!! (To be fair to myself, I've only started to design the benchwork in the last few months).
(Slow) Dave
hon30critter What would you use for corner blocks? The suggestion was made to use 2x2s but I'd be concerned about them splitting since they would be less than 4" long. I guess if I pre-drill them that would not be an issue?
Rich
Alton Junction