one more wood question

[robertglines1]

when installing hardwood floors can planks be full length across bus..I have noticed most have end joints.necessary? Bob

[eddiepotts]

Robert, if I am reading this right you do need to leave a 1/4" gap around the edges for expansion. Plus you do not want any of your joints to line up. So take your first board and cut about 3ft off and start there with the end that has the tong on the end.Use something that is a 1/4" (like a strip of plywood) and lay your next board down backwards up against the board. where the two joint would meet mark it. It does not have to be exact (your trim will cover any imperfections. Cut there. You should have the piece with the grove on the end. Side it in place. You will have about a 1/4" gap on the end. Next start with the other piece that you cut off with the tong on it. Put it in place for next row. Continue on with a new board measuring the same way. Of coarse add glue or nails depending on what you are using.

[cody]

Bob, I'm assuming you used your planer to S4S them, so you didn't t&g the ends only the sides. one question I have is did you cut any relief into the backside of the boards, the relief is a stabilizing ellement that keeps the wood from cupping or warping, also if you have a camphered edge from your cutters you can duplicate that camphur on the ends so that they can butt up together and match.  For the finishing I would use a high solids varnish, a polyurathane type specific for marine or exterior use, in the past it was simple spar or not but now you have many choices including a product called Bartop that many people are using that gives the apperance of like 20 coats. Lightly sand between coats to scuff the surface for better adhesion.  A coat of stain, if you want any, should be wiped on before you varnish, it has to go directly into the wood surface, it'll enhance any grain patterning or tigering you may have in the wood.  Leave a small gap around the perimeters for expansion.  The poly's are a plastic varnish and very forgiving for the long run, they don't generally crack or or craze in time cause of the flexability built into the poly's.  I wouldn't worry about running the wood full width, you can do that without a problem, as a matter of fact, I would recommend that every few boards you run one full width to even out any runs that may be forming in the pattern.

[Runcutter]

Bob, the way I read your first post makes me think you're installing the boards with the length running across the bus.  Whether you're doing that, or (the more customary?) lengthwise to the bus, you'll need to account for wood movement.  Wood will continue to move, and change with the seasons (moisture content) of their environment.  Good construction takes that into account, you can't thwart mother nature.  

Boards will cup, as the tree rings try to straighten themselves out.  Wood will move, primarily across the grain, with humidity.  That's the reason for frame and panel constuction of doors.  One of the "rules" is -- inside of tree, outside of project.  So, if the wood cups, the side edges go down, keeping the joint tight.  Tongue and Groove, of course, helps keep the joints together.  That also puts the harder part of the tree on the wear surface.  

If you're looking at the end of a flatsawn board, the rings should look like     \         /    
                                                                                                                  \ __ /                                                                                                                      

It's easy to use a router table to put tongues and grooves on boards - both the sides, and the ends.  Several suppliers sell decent tongue and groove bits - I personally like CMT, but I also have a few Freud bits.  Stay away from the cheap imports, not worth the money.  As Cody mentioned, you could put a small chamfer on the tops, that would disguise any slight movement in the joints.  It could, though, be a dirt catcher.  

Another principle is that whatever you do to the top of the board, you should do to the bottom - so moisture reacts the same on both sides.  When I resaw a board to make veneer, or a bookmatched panel, I take it right from the bandsaw to my thicknessing sander or surface planer, to open up the pores on the side not cut.  That would argue that you would want to finish both sides of the board with the same material, same number of coats.    

If you install the boards lenthwise, parallel to the long axis of the bus, you'll need to leave a little room against each wall.  If you install across the bus, each board will move, so you could run into difficulty if you butt the boards tightly to each other.  The T&G principle is to anchor one edge of each board, leaving the other edge free to move, but it's anchored in the vertical plane by the next board.

One alternative that I've seen pictured here, is to install the boards at a 45 degree angle to the long axis of the bus.  That could also take care of wood movement issues, but it depends on your personal taste - can you accept something not parallel, or at 90 degrees to, the axis of the bus.
 
A disclaimer, I'm discussing woodworking in general.  I don't have any experience with wood flooring in my coach, I'm keeping the original RCA Rubber flooring.

Here's a pretty good write-up on how wood moves.

http://www.woodworkerssource.com/wood_movement.php


Arthur

[eddiepotts]

Just keep in mind if you do chamfer the boards and run them across the bus you will need a vacuum to clean instead of a broom. You will fight the dirt in the chamfer from now on.

[cody]

Depends on how deep the camfer is, 99% of the hardwood flooring available now has a camfer of some sort, it's very hard to find hardwood flooring that has a T&G with a butt seam tho that is the traditional way from years ago, the reason I asked is because Bob has a sawmill and I'm assuming also a commercial planer and depending on the age of the cutters it may be camfered already, newer knives seem to do up a camfered edge and older ones the butt seam, I have both and my old oliver uses the butt edge for a T&G application, my newer delta puts a slight camfer on the top and I kinda like that for appearance, the camfer isn't deep enough to keep a broom from cleaning it.

[Runcutter]

Bob, I didn't know you had a sawmill, so you probably already knew everything I mentioned. 

Arthur

[robertglines1]

all wood was quarter saw..was going to run at 20 degree angle across bus..just wanting to try something differant..one piece boards to 14 ft long is no problem  longest would be 102 inches  96 inch inside width plus 6 inch for end angle...is 102 inches two long of run for expansion and contraction? will leave end gap along sides. 3/4 inch board ..have several thousand board ft dried so can select grain..tried one yesterday sue turned out beautiful and came out of plane slick to touch.  will remember slight camfer wood is at 18% rite now.planning on 3 inch width is that good ??or go wider.have many 14 inches wide assumed they would be to hard to keep from warping.will be placed over 1/2 plywood with sheet lead below finished floor..if I would run length ways how long could I go???Bob  a beginner in wood working

[niles500]

If I had access to the lumber you have - I'd do it just the way you are planning - FWIW

[Runcutter]

Bob, sounds like you have things well in hand, and you have a wood supply that makes many envious.

Length isn't an issue with expansion/contraction, since the movement takes place across the grain - not lengthwise.  You also have the right direction in using narrow boards, to eliminate (actually, reduce), cupping.  The wider the board, the more prone it is to cup - especially since part of the board will likely be flatsawn.  Quartersawn, narrow - the way to go.  The current moisture content sounds high, but I'm used to making furniture in my shop - not something that will, essentially, be out in the general atmosphere (buses breathe, and temperature/humidity will vary when not occupied by humans).

Running at that angle, with movement across the grain, it is possible that some slight movement against the wall will happen - so your planned gap sounds right on.

Think about how you'll anchor the wood floor to the subfloor.  The wood will move, but the plywood subfloor is more stable.  That leaves construction adhesive (liquid nails) out, it's not like laying tile.  Back, perhaps, to the tongue & groove - nail at an angle through the tongue, then slide the next board (groove) up, nail through the tongue of that board.  That way, each board is anchored only at the tongue, so expansion/contraction can happen at the grooved edge.  Since the groove is mated with a tongue (that, itself, is nailed down), the groove is anchored vertically.  

If you do chamfer, my thinking is very, very slight - just enough to disguise minor differences in height from board to board.  You're creating a very subtle shadow line.  Will you like that?  Alternately, would you be able to run a belt sander over the floor (with the grain, up to 220 grit paper - to flatten it out?  Would that even be an issue?  Personally, I'm not sure I'd want to chamfer flooring - think of the wood floors you've seen.  (I do plan to make some cedar tongue & groove for the outside of the house, and I will chamfer that).    

Your profile shows that you're in Evansville, Indiana.  I'm a regular at our local Woodcraft store, where all of the employees and most of the customers are woodworkers - from professional to neophyte.  You might find it interesting to visit the Woodcreaft in Evansville, and get to know some of the folks .  Here, a lot of the discussion and give and take revolves around woodworking ideas.  They've saved me from more than one bad mistake.  

By the way, what kind of wood is it (it'll help me admire the job you're doing from afar)?

Arthur

[robertglines1]

Red Oak  most logs were 30 inch out of old growth woods (not wind twisted) I also have a lot of poplar that I'm using for frame work..have black walnut drying but is to dark to put next to the cherry cabinets. Wife Judy said! got to keep her happy she does all the upholstery work.               Thanks again to all..I'm still figuring it out..Have hardwood floor nail-er.    will not be up to the pro's but my only cost will be finishing material..

[Runcutter]

Nice - I just saw your PM after I'd posted my wood question.  The red oak should work well with the cherry, and I agree that you don't want to go too dark in the bus.  Dark floor could make it look more cave-like. 

Personally I do like cherry and walnut, and I use maple and walnut together quite a bit.  Several years ago, I made a dinette table for the 4107 out of curly cherry and walnut.  While you don't want to mix too many different woods, in a project or a room you might find places to use the walnut as an accent.   

Now, picture Homer Simpson saying "Hmm, doughnuts", and let's all say together "Hmm, Black Walnut."

Arthur

[mike802]

I have to agree with Runcutter, 18% moisture sounds high.  I am a professional furniture maker and upholster and we like to keep things down to around 7 to 8%.  At 18%, I would be worried about shrinkage causing gaps in the finished flooring. I am laying a pre finished oak floor in my pantry right now and it is running around 6%.

[robertglines1]

thanks: Mike  that's what I need to know.no problem will cut to width and strip for awhile. can be last thing to go in.our humidity has been low and I haven"t checked it in a couple weeks.Haven't got access to kiln.

[bottomacher]

I think you will find that only prefinished wood flooring is normally chamfered; that prevents damage to the delicate square edge in shipment and handling. Raw lumber is square cut, since it will be sanded in place and edge damage will not then be apparent, and matching the finish for touch-up is not a factor.