# Surfacing 4' x 8' glued up panels



## damnitboy (Mar 3, 2012)

Hello everyone,

I am building a setup for surfacing 4 x 8 glued up solid stock panels. I have purchased 4 pcs of linear shafting with the linear bearings on ebay (around $300) and instead of the usual way of using a wooden jig I plan to run the router on the linear slides with a 2-1/2" surfacing bit.

Anyone have any input on things I should could or how to add to this project to improve it. This is a common task and I want something that will be fast and clean. Budget within reason is not an issue.

Thanks,
-Eloy


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## ggom20 (Feb 1, 2012)

Hello!
Well , you can make nice piece of machinery out of your linear shafting!
You did'nt say what lenght you bought.
Like router-lathe , routing slots , universal precision sliding mitre for router and circular saw, a copiing 3d router, 
Many things.
*IMHO:*But just for cleaning surface, i' ll consider Harrysin ski system, its costless, fast to make and quite efficient!

The only point that could make this design fail a litle precision is the router's base:
Some bases uses too thin steel bars, some give an angle, when you screw router lock
to the steel bars, then the router is not staying horizontal , needs a bit of adjusting.

http://www.routerforums.com/jigs-fixtures/23799-beginners-guide-making-router-skis.html

Regards


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## CharleyL (Feb 28, 2009)

Trying to make 4' X 8' panels from solid wood does not sound to me like it will be very successful. With any change in humidity the panel will change shape. It may be flat one day, but look like a potato chip the next. Wood changes it's size too much with moisture content changes for this to work out well. 

In fine furniture and paneled room construction it has been common to break up larger areas into frame and panel designs to allow the wood panels to move with changes in moisture content. It's a lot more work to do this type of construction, but it works out very well. I would never try to make a solid wood panel larger than about 1' X 2' and expect it to remain very flat, unless it was built into a frame with provision for it to move within this frame for any changes in moisture content.

Charley


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## damnitboy (Mar 3, 2012)

Good point Charlie,

I have had to go to a three ply glue up to solve that problem. I A little trickey to get three levels thick by 4' wide but using cawl's it can be done. It takes work but these are very expensive projects. Thanks for pointing that out. I normaly just laminate to a pc of MDF but some clients insist on "solid wood"

-Eloy


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## damnitboy (Mar 3, 2012)

Hello Gerard, good tip. I am building the same principle as the ski's but more ridgid. By the way, on the linear slides I will have 12' x 6' of travel.

-Eloy


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## KenBee (Jan 1, 2011)

I am working on a set of skis like Bobj3 has and pictured below. Mine is 24 inches long with a cut down phenolic router table insert plate for the router. Going to use a Milwaukee 5615-20 router with the handles removed and a 2-1/4 diameter drawer lock bit to plane the stock. Got the extrusion off Ebay for around $30.00 shipped. The holes in the ends of the extrusion are perfect for tapping 1/4-20 threads to attach knobs for height adjustments. As it stands I will have invested less than $60.00 when finished excluding the router of course.

I also have a Woodhaven planing jig that is a monster and as such will plane larger stock than the ski will. I wanted the ski to plane 50 or 60 boards that average 12 x 6 x 3/4 down to 5/8 or less depending on the application as well as being easier to take down and store when not in use.


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## WillMatney (Oct 6, 2011)

Without knowing the size and type of shafting you have, it would be hard to predict how it will act as far as deflection goes.

I used to design industrial machinery such as this, before I became disabled, and for the size of project you're going to do, shaft deflection will be a problem, unless you have some pretty big shafting and bearings. Shaft deflection can mean an uneven cut, and vibration.

Normally, for a project of this size, the shafting to be used on the longest length you have, which will be 8 feet, plus some for the carriage, should be the supported rail-shafting mounted down to a fixed and very sturdy table. This is the shafting that mounts down onto a solid aluminum riser, and goes completely under the shafting making it into a rail. If you tried to use, say two pieces of shafting only supported by its ends at around 9 to 10 feet long, it could cause a vibration when the cutter was mid-way in the work, especially if you took a very heavy cut. The other direction, or axis, will be a little over 4 feet, and you could probably get by with end supported shafting here, as long as its big enough.

An idea would be to take a look at a CNC routers construction of something this size, and see what was required to do it without vibration.


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## ggom20 (Feb 1, 2012)

Hello!
Interesting project!
can you send picts?
Are you making some sort of real heavy plywood or am I wrong?

My grand father made a table like that. still got it , he made a 45° frame around it. 
It never did move, but at this time,They where patient.
I'm very sure he did use some 20 to 50 Years of drying wood.

Some of the best woods for difficult jobs are the wooden beams and framing took
out at destruction of old houses.

Regards.


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## WillMatney (Oct 6, 2011)

*Extrusions*



Ken Bee said:


> I am working on a set of skis like Bobj3 has and pictured below. Mine is 24 inches long with a cut down phenolic router table insert plate for the router. Going to use a Milwaukee 5615-20 router with the handles removed and a 2-1/4 diameter drawer lock bit to plane the stock. Got the extrusion off Ebay for around $30.00 shipped. The holes in the ends of the extrusion are perfect for tapping 1/4-20 threads to attach knobs for height adjustments. As it stands I will have invested less than $60.00 when finished excluding the router of course.
> 
> I also have a Woodhaven planing jig that is a monster and as such will plane larger stock than the ski will. I wanted the ski to plane 50 or 60 boards that average 12 x 6 x 3/4 down to 5/8 or less depending on the application as well as being easier to take down and store when not in use.


If he used something similar to the 80/20 extrusions for the long rails, on the 8' axis, like the 2" x 4" sections, he would be better off, or I would think. They also have the nylon linear bearings to fit the extrusions, and the extrusions could be easily mounted to a table or level floor. He could then use the round rods and bearings for the other axis, but my guess is that he would need at least 1" diameter rods, or larger, to stop any vibration.

He's using a 2-1/2" bit, which takes a good size router, and it creates a good amount of cutting force, so I'm worried about him getting vibration, and sway or sag in the rods over a long distance. The idea of the tubing is a good one.


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## damnitboy (Mar 3, 2012)

Thanks for the response Will, 

You made some good points. I have 25mm supported shafting, The long rails will be mounted to a table so I am sure they will be fine. What is your opinion on the cross travel since it will only have the additional rigidity of the rail support. Since it will be inverted I will have spacing brackets over both ends over the long travel shafting. The plate to mount the router will be recessed to get the spindle down to the work. I would appreciate knowing what you think.

-Eloy


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## damnitboy (Mar 3, 2012)

Hello Gerard,

Plywood is a good guess. I am actually building out a law office and the workpeice will be one of three parts for a conference table top on this project, hence the solid stock. I have done a few jobs similar and decided to make something that is quicker than the way I have done it before.

-Eloy


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## CharleyL (Feb 28, 2009)

If I needed a 4 X 8' flat panel I would purchase a good quality veneered sheet of 3/4 or 1" plywood. It would be far more dimensionaly stable than trying to make a flat panel from solid wood. Add a ribbed frame or torsion box to the table design to support it and it would remain flat and stable for a very long time.

Charley


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## ggom20 (Feb 1, 2012)

Hello!

shaft mounting for a 8 feet travel on a 25mm steel round ?
IMHO:
No need to calculate, it will surely move too much.
Unless you go for a support in the midle and change the moving bearing for 
a 3 bearings at 120° thus leaving possibility for supporting the sliding bar.
That makes 6 bearings with some kind of machined wheel to run on round profile.

Regards


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## WillMatney (Oct 6, 2011)

*Design*



damnitboy said:


> Thanks for the response Will,
> 
> You made some good points. I have 25mm supported shafting, The long rails will be mounted to a table so I am sure they will be fine. What is your opinion on the cross travel since it will only have the additional rigidity of the rail support. Since it will be inverted I will have spacing brackets over both ends over the long travel shafting. The plate to mount the router will be recessed to get the spindle down to the work. I would appreciate knowing what you think.
> 
> -Eloy


Well, the 25 mm shafting is the same as 1", or very close to it, as 25.4 mm is one inch. I take it you have four linear bearings to mount to the router plate, one per each corner? If so, I would think it will probably be enough, as long as you don't go over about four to five feet in span for the shafting length. The rods will need to be a little over four feet, because the router plate will need to extend past the work somewhat on each side for the bit to cover a full four feet.

The main thing is, mounting the shafting at the ends, rigidly, where it will ride on the shafting for the long axis. This long shafting should be connected to the table at least every two feet or so to keep it as rigid as possible.

You might buy two pieces of heavy aluminum angle, maybe from 80/20's eBay site, to make the carriages for each end of the four foot cross shafting. You can mount two linear bearings under each angle to attach to the long axis shafts, or the eight foot ones, and mount two 25 mm rod clamps on the top of the angle to hold the four foot+ shafting. They have these made from aluminum castings, and are available on eBay for CNC builders.

The trick is to keep everything spaced a close as possible, as far as the distance between the linear rods, etc. go. This will give a minimum of deflection in the router plate, because it will be smaller, and in the carriages for the rods.

I think I saw some 3" x 3" aluminum angle on ebay the other day, with 1/4" thick legs, which would be about right for what you need. The rod clamps are available from a few places, mostly from the guys supplying home CNC building components. The clamps use a couple of bolts underneath to hold them, and the top is split, with a through-bolt to tighten it down onto the end of the rods. There's some others made from a block of aluminum, where the top comes off, and splits the rod hole in half, using that to clamp the rod with two screws.

Last, that shafting is very hard, and hard to cut or drill. To cut it, you will most likely have to use an abrasive cutoff to do it, as I doubt a band-saw will handle it, without quickly dulling the blade. To drill it, you may have to take it to a machine shop, as trying to drill it dry on a wood shop drill press may not be advisable. To mount the shafts, we used to grind a flat towards the ends, and use a set screw to hold it. We couldn't mill the flat, it had to be ground, as its just that hard.

I hope this helps, as it can be hard to explain what one envisions.


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## damnitboy (Mar 3, 2012)

Hello again Will,

All were good coments, I appreciate you helping with your thoughts.


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## damnitboy (Mar 3, 2012)

Hello Gerard,

I appreciate your input.

-Eloy


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## damnitboy (Mar 3, 2012)

Hello Charlie,

I agree with you but my client insists on solid wood. I agree with you I could veneer a panel myself having him select a grain that suited him. It would be stable, tons cheaper and no body would know. But it's his money so here I go.

-Eloy


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## gav (Oct 12, 2009)

People glue up solid wood panels of this size all the time to make conference tables. I wouldn't worry about it being an issue.
Check this one out that I guy over at lumberjocks created.









mahagony Meeting table - by aviad mishaeli @ LumberJocks.com ~ woodworking community

Check out this video of a large slab planing sled. It's probably one of the better ones that I've seen as far as ease of use and simplicity goes.
Large Log planing - YouTube


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## ggom20 (Feb 1, 2012)

*Please make a sketch.*

Hello!
I'm carrefully reading everything here, and it's difficult.
WillMatney seems to know about it.
Think it could be time for a good litle sketch, just to figure out.
So i could input sizes and forces to my Tech calculator and output values for deflection.Its only a static calculator, but it's a start.
I could start with a wheight around 15kg on long travel.
And then vertical cutting forces my estimation would be to inputa minimum of 30 kg for ridgidity i even think 100Kg would be better.

What could be the distance betwen a bearing pair ? say 1 foot or 10 inches ?
If this travel holder is very ridgid it helps a bit .
As WillMatney said, the shaft would hold better if strongly hold at ends.
Like stuck in a concrete wall It goes for super- strong support.
I can see no need of drilling or grinding shafts, i' ll keep them as they are.
The holder could be two half cylinders with a pair of bolts.
Thats exactly how it is made in a Thermic motor, simple and strong.

Regards


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## ggom20 (Feb 1, 2012)

Hello!

Made a quick calculation:

lenght 2.4m 
ends ridgid support
Travel is one bearing one point for force
Shaft 25mm steel Youg module: 210 000 MPa elastic limit 250 Mpa.
True steel but not hight grade.

Force: 115kg midle deformation 40 mm
Force 15 kg midle deformation 3.5 mm

Go for better steel:
steel 45 SCD6 young module 220 000Mpa
force 15 kg deformation 2.6 mm

If my calculator works, deflectionn is obsiously too big.


The design works with central ridgid support here with 15kg
deflection is 0.3 mm

Oups ! Been putting all force to one bar, means deflection is to be divided by two with two bars
Or you can think about 15Kg on each makes a 30 Kg total force.


Regards


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## allthunbs (Jun 22, 2008)

Hi Eloy:

I've just picked up on this. Talk about interesting.

Ok, I've just finished a 65 pc. 3'x4'x1.5" glue up in maple. If you keep your sticks small, you can overcome some of the tendency to warp. I setup my glue-up so that the cupping is opposed all across the table. One stick is set to oppose the cupping of it's neighbour. I'm also using stringers on the underside to "compensate" for the need to warp. There are two elements that will aid, keeping your sticks narrow and your top thick. At least, I'm hoping. That's what I've done and I'm not going to finish mine so I'll tell you in a few weeks, how well it works. Spring thaw here is very wet.

As for skis, the longer the rods the more bounce. You're dealing with one heavy bit so you'll need a heavy router. I've actually run into harmonics on the rods. I'm going to recommend that you support the rails in close proximity to where you're cutting. You'll also find that your router in such a setup is for "rough" work. You'll still have to clean it up with a scrub plane and then a smoothing plane then scrapers. You just must might be ahead by starting with a scrub plane, cross grain. That will take it down quick enough. If you're worried about it being perfectly flat, the carbon trick will deal with that.

But, then I'm talking through my hat in the hopes that I can encourage your grey-cells to improve on my feeble attempt to help.


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## damnitboy (Mar 3, 2012)

Hello everyone,

First let me say thank you all so much for your input. I wish I would have known about this forum before committing on my plan. Fortunately I still have the backup of subbing this out to a CNC shop that I use. I always end up in interesting jobs like this so I am going to run with this project. I want to bring it in-house. Please feel free to share more input. I will keep you all posted on my progress once I get started.
Thanks Again!
-Eloy


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## ggom20 (Feb 1, 2012)

hello!
IMHO:

It 's possible to use the 25mm rods but change bearing guiding to a one 
with 3 wheels at 120° it gives acces under the 25mm rod for support it .
For 4 supporting points, just supporting, not seeled and total 30Kg deflection is 0.27mm 1/10" Will be sanding, but that's not a mirror.

With a round pipe 75mm inside hole 65mm on simple stands at ends
With 15Kg each bar it gives 0.6mm at center for a total 30Kg applied.

This is acceptable but quite heavy...

Regards.


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## ggom20 (Feb 1, 2012)

Hello again

There might be an other way to go throught this project.
A suspended rail system with a 1 ton capacity at ceiling level.
It could go on wheels and rails, and also help moving things around.
It would bee possible then to add mass to the router slide to keep vibrations low.

In fact, all long precision machines I have seen are pretty heavy ones.

Regards


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## ggom20 (Feb 1, 2012)

A good machine can be made with 25mm round
But it means heavy *locking* support example is every 0.8m
Steel 25mm , 15Kg ,30Kg total, 4 locks, deflection is very low less than a 0.1mm!
But then to achieve this heavy locking a big construction-type rail will have to be installed to hold the 25mm bar with strong holders.

It make me think, the simpler the better! 
>railway rail and wheels.

Regards


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## WillMatney (Oct 6, 2011)

*Deflection*



ggom20 said:


> A good machine can be made with 25mm round
> But it means heavy *locking* support example is every 0.8m
> Steel 25mm , 15Kg ,30Kg total, 4 locks, deflection is very low less than a 0.1mm!
> But then to achieve this heavy locking a big construction-type rail will have to be installed to hold the 25mm bar with strong holders.
> ...


Yes, your seeing the big picture for it. If you were just carrying the weight of a router, and doing no work with it, things are not too bad, but once you start cutting, and with a large bit, the cutting force can cause a good bit of movement, and then vibration. Though, it is according how much of a bite you're taking with the bit, maybe 1/8" to 1/4" deep of a cut for leveling the piece. There could also be harmonics involved, but a slight change in cutting speed could null that.

There would be another way, if you have enough rod, and that would be to use four rods on the short axis, instead of two, which would divide the forces by four instead of two.

To be honest, you would want no more than maybe 0.002 - 0.003" or so deflection, with the router sitting mid span, and that would be static deflection, without cutting forces. The rule of thumb we used was to design for a maximum deflection of 0.001" of deflection per foot of span, using the the live or dynamic loads, plus the static weights.

If you're using the hardened rods that come from a linear bearing set, they have a high working strength in kips, and very minimal deflection due to it, as would be compared to a cold rolled rod of something like 1040 material or so. These are hardened to something like 55-56 Rockwell C hardness, and ground, or for example, they're hardened like the gear teeth in a transmission. The tensile strength will be a lot higher than it will be for plain 1040 CRS, or similar. You should recheck your numbers, and see what the proper numbers are for these rods. The manufacturer should have this info, or you can roughly guess it by looking at the rod specs from Thompson's website, or another manufacturer.


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## ggom20 (Feb 1, 2012)

Hello WillMatney!

You right about the steel, it might be better than a young module of 220 000 Mpa.
but this not change much the results.
Deflection is just in inverse proportion to young module.
Double the youg module (Elasticity and you divide by two the deflection).

Not enought, geometry like going up to 75 with 65mm inside hole round bar affects a lot more the result 75-65 was just a guess don't even know if it's a standard.
It gives a good result like 0.3 mm ( About 1/1000") for 30 Kg on two bars.
With the much simple construction, no need to strongly hold extremities.

If you can get this Young module, it could help, didn't find it for HRC 55 steel.

Regards


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## WillMatney (Oct 6, 2011)

*Shafting tensile strength*



ggom20 said:


> Hello WillMatney!
> 
> You right about the steel, it might be better than a young module of 220 000 Mpa.
> but this not change much the results.
> ...


Thomson's rods are case hardened to RC 60, but if I remember, some other brands are a little less, so I mentioned RC 55 or so. Anyhow, the Thomson 1566 steel shafting's numbers are below:

For reference 1060/1566 grade per McMaster Carr:

Tensile: 335,000 PSI-Case; 100,000 PSI-Core
Yield: 250,000 PSI-Case; 75,000 PSI-Core

I couldn't find anything on the 1566 but its chemistry, but since 1060 is supposed to be similar (about same in carbon), below is for a heat treated 1" rod, at RC 25 hardness, but this is through hardened, not case hardened, however the tensile strength is close.

Tensile Strength, Ultimate: 883 MPa, 128000 psi
Tensile Strength, Yield: 545 MPa,	79000 psi
Modulus of Elasticity: 200 GPa, 29000 ksi	

Now, you can get these rods either case hardened, or deep hardened, but since you probably don't know which you have, it's better to figure it as case hardened, and use 100,000 PSI or 100 kips for bending or deflection moments.

Thomson Linear Bearings & Rods

AISI 1060 Steel, oil quenched 845°C (1550°F), 595°C (1100°F) temper, 25 mm (1 in.) round

Also, I used an online calc for the deflection of one shaft, supported at both ends, and the weight in the middle. Yours would be slightly less than shown, as the weight would be through the bearings on the router plate, and not centered exactly. For the c dimension, or the neutral axis, I used 0.5" for the radius of a 1" round rod. I used 20 pounds for a total weight, including router, plate, bearings, and some cutting force.

Total Load : 20 (lb)
Length of Beam - L : 48 (in)
Moment of Inertia - I : 0.049 (in4)
Modulus of Elasticity - E : 29000000 (psi)
Perp. distance from neutral axis - y : 0.5 (in)
Support Force - R1 : 10 (lb)
Support Force - R2 : 10 (lb)
Maximum Stress - : 2449 (psi)
Maximum Deflection - : 0.0324 (in)
Deflection for two rods: 0.0162"

Beam Calculator


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## ggom20 (Feb 1, 2012)

Hello willMatney!

Lots of input! all in inches and PSI !

I' ll take it seriously and do that tomorow , got to translate units and so, not really familiar
with it , I' ll be carefull and compare results.

About comparing , some of my calculations implies ridgid at both ends,
(it shows on pictures)
I will not state that anymore.It make the thing more complex.

Then there is already a question about "deflection of one shaft, supported at both ends"

-Q1:
Does it means simple support at both ends ?
(If Yes now we calculate the same way.)

My last idea whas to think about leaving free flexibility at both ends , because ridgidity
would imply use of a very solid table or beam to hold things straight. 

If I input ridgidity at both ends, the calculator would calculate a deflection quite less
but would state that end holders got an absolute ridgidity.Witch is difficult to achieve.

So now I would consider the rod being the only ridgid thing, support is only for 
support.

-Q2:
You choose 20 pounds each rod , it makes about 10Kg for a beam ,
I did choose 30 pounds each rod ,is that right?
My evaluation is for a total of 60 pounds.
-Q3:
What is the goal ? about deflection and forces?
Not very well defined at the moment,a mirror? what is acceptable deflection for a mirror? A mirror can go down a few micrometers, not for us...
-Q4:
Just noticed:"Length of Beam - L : 48 (in)" that makes 1.2 m
I thought it was about having 8 ' travel , makes 2.4 m
Or you got central support and two travels .

Maybee that 1/100" on total could be good enought (0.25mm)


My last opinion whas about keepin it simple, one travel 2.4 m.
Simple support, no table ridgidity, only rod is ridgid.
As big as it needs to be 3" round or 4 " round if needed. 
not so heavy in fact and sure it works.

With the 75mm(3") pipe bored 65mm , 2.4 m (8') the results where good:
60 pounds on center would give 1/100 " deflection.
so with 20 pounds it gives 0.003 " at center.

I apreciate our efforts to make it good,fun.

Regards.
Gerard


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## WillMatney (Oct 6, 2011)

*Explanation*



ggom20 said:


> Hello willMatney!
> 
> Lots of input! all in inches and PSI !
> 
> ...


Gerad,

The cross rods (48 inch cutting axis) will not be mounted rigid, even though they're clamped down solidly, so its a simple support. Since they will travel on the long axis (96" axis) rods or pipes, using bearings or wheels, they will give, so they are not rigidly mounted like a rod welded at both ends between two columns. Also, in your case, there will be rod bearings on the router plate, so the distance between those come into play, and its just that online calc doesn't have the ability to figure this, so it concentrates the load in the dead middle, instead of spreading it out over two bearings, say 8 inches apart. So, your deflection will be a little less than what was shown by the calculator, but not much.

I just roughly guessed 20 pounds for the load, as I was trying to count the weight load of the router, a base plate, and four rod bearings, along with a small amount of weight loading being generated by the bit during a cut. There's really nothing you can do on this but estimate it, due to the cutting force, as it will not be known until you try it out after its built, (unless you can measure it beforehand). Generally, the engineer tries to over-estimate the loads. The total load weight could be more than this, so I'm not sure. The only way to be close, would be to weigh the components, and estimate any dynamic loading.

Over the 96 inch cutting length, you need those rods, or pipes, supported every 2 to 3 feet - (1 meter), or so to avoid deflection, etc. That is, if you use 1 inch rods here too. If you go with big pipe, etc. on the 96 inch cutting length, it doesn't have to be supported as much, as the bending moments change with the size, and are less as the diameter goes up. The weight load they'll see will be the total weight of the 48 inch cutting axis cross rods, rod trucks with bearings and or wheels, the router, router plate, and bearings, plus any live or dynamic load, which will not be that much.

A good idea would be to look at the pipe or tubing size used on one of the large panel saws that they use at a lumber yard or home center, to cut plywood or sheet stock for their customers. The ones I've seen use something around 3 inch diameter tubing, but I don't know what the total specs are, with the internal diameter.

What I envision is two 1 inch rods that will hold up a router, and be long enough to move the router for a 48 inch cut. These rods will be mounted to something like an aluminum angle on each end, which has bearings or wheels underneath, that will run on the rods or tubing for the long 96 inch cutting axis.

Best,

Will


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## jw2170 (Jan 24, 2008)

*Here come the Luddites........*

Hi all,

From an outsiders perspective, it seems that the thread is moving toward a new Brooklyn Bridge. (tongue in cheek.........)

The slab is only 4 x 8? 

I would keep it simple, as in the video Gav posted for rough planing and then finishing with hand planes or scraper.

Large Log planing - YouTube

This jig could probably be built with a couple sheets 3/4 ply..


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## GulfcoastGuy (Feb 27, 2012)

If you make the rails working, down the road there's a real automation potential. A couple of low end servos and an equally low end PLC and you could setup a job and walk away while it planes. But you'd have to do something for power cord management or you'd cut right through it sooner or later.

GCG


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## ggom20 (Feb 1, 2012)

Hello!

Now we know that 25mm rod with circulating ball-bearing don't work.

A cheap wheel and rail is easy to achieve , but it has got a problem
when dust goes under a wheel, useless to make a rail ridgid to a 0.2 mm 1/100"
If a 1/10" chip of wood lift the wheel.

This relatively cheap system could work if at a 2.5m up to avoid chips, and with 
brushes for automatic cleaning and some protective panels to block the way for chips.


The round and brass-guide in a 3 " size is good ,resist to dust, but very expensive.


And by the way with a 250mm(10") between guides on the long distance 3.6m(12') and a long cross distance like 1.8m 
(6') it gets to the point where it might be self-locking if too much wear in guides.

Solution could having a travel with 900mm(3') between brass-guides.

There is also out of the shelve solutions for everything, they got the travels ,sliding
on tech plastic, travel guiding for cables, possibility of electric linear travel and so on:
igus® DryLinÂ® W linear guide system - Program overview

It just need a coherent structure like 1" plywood and that's all.
(I would add a steel flat like 100mm x 5mm screwed to it at rails location).

It resist to dust and garanteed if well selected items for 1000 miles of table moves
at final accuracy to a 0.4mm 1/64" after years of use.

The cost could be around 1500 $. (Out of automation)
A specialist in electronics could motorise it for around 1000 $.


Now if comes to what Damnitboy whants to do.

Regards.
Gerard


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## WillMatney (Oct 6, 2011)

Gerard,

You can keep the rails clean by mounting a brush in front of the wheels, or a wiper made from rubber. We used a brush to do it, or like a small scrub brush with non-metal bristles held in a mount. I've seen some use compressed air to blow the rail off.

You can make a good wheel, or set of wheels, by using ball bearings, which are pretty cheap. Just buy some that have a through hole that will match what bolt you want to use, and you have it. They also make a flanged bearing, sort of like a railroad wheel, and those would work too.


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## WillMatney (Oct 6, 2011)

jw2170 said:


> Hi all,
> 
> From an outsiders perspective, it seems that the thread is moving toward a new Brooklyn Bridge. (tongue in cheek.........)
> 
> ...



I think he would be better off with the plywood like you mention. He should use Baltic Birch plywood, and the reason for this is its more stable than the 7 ply, 3/4" made here in the US, as Baltic is around 13 ply's built up to 3/4".

One could make two box beams for the cross cutting, say around 6" x 8", and mount a piece of miter track on the bottom inside edge of each. Then, mount a good miter bar on each end of his router baseplate, and slide it into the tracks.

He could have this rolling on some leveled beams made of plywood, with an aluminum or steel angle for rail, and use some ball bearings for wheels, and he would be done.

Best,

Will


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## ggom20 (Feb 1, 2012)

Hello!

That's Damnitboy project.
Time for him to decide something.
About aluminium rails, you are right, some are very cheap , like the 4" x 3/4" ,I use
for levelling concrete floor with an assembly of 3 of those in paralell, ridgidity is good
enought, and its super flat garanteed, then a big bearing can roll on it.
With cleaning brushes, of course.Some nice ready-made wheels exist too, whith 
some polyurethane around. They use them for some lift and carry systems :

Galets polyuréthane pour transpalettes 77006010

Yesterday whent around american's metal suppliers,Found a good aluminium rectangle $122 for 12' (3.6m).

Order Aluminum 6061 Rectangle Tube in Small Quantities at OnlineMetals.com

The calcutation is very good with that one.
Deflection should keep under a 0.1mm.or less with the use of more bolts
to screw it on your birch 3/4 first choice plywood.

Have you been looking at those from Igus?
Nice and clean,and fast, seen them on an industrial show 2 years ago.
Was very impressed, cause you got everything ready in a matters of hours.
igus® e-chains®, chainflex® cables, iglidur® bearings, igubal® bearings, drylin® linear motion

I also can give links to a german system, but that's a lot more expensive
it's all hard steel, brass, precision machined for a 10 Years 24/7 working life.
Could be all inox etc.Thats for big industry:
Mechanical Components from RK Rose+Krieger

For me I'll go for plywood and alu rails.The cheap way.
And then add some steel cables for motorisation and automation,
Easy with step motors and a pc.

They sell piloting software, power control for step motor and everything is ready
to use.A bit of programing.
.
But now again, not my project.
depends on Damnitboy skills and money he's going to invest.

IMHO:
Even a $4000 machine that could plane, sand, spray, polish tables
could be worth if it can work alone for hours...

Regards.
Gerard


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## damnitboy (Mar 3, 2012)

More good ideas, I know we can do this. I am racing a deadline on a job right now so limited time for this project for awhile but once it starts, I will upate all of you with pictures of it's progress. Thank's and I appreciate the input.
-Eloy


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## ggom20 (Feb 1, 2012)

Hello!
Re-stard this thead when you will be ready !
You could also input your design when decided something.

Regards


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## damnitboy (Mar 3, 2012)

*** Update on this project*** 

I ended up buying the Woodhaven 3004 51" planinig sled.Amazon.com: Woodhaven 3004 51" Planing Sled: Home Improvement (There is a link to a video on that page as well) Completed the job with no problem. It is alot less than I had pictured this project being but we have taken so much new work I needed something easy on my time and this did the trick.
I hope all is well for everyone and happy woodworking.
-Eloy


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## ggom20 (Feb 1, 2012)

Hello!
Ok!
Send a pict or video!
Let us know the good and bad about this product,
It' s cheap and could be interesting me too.

Regards


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## GeorgesG (Mar 19, 2012)

GeorgesG
Good luck , I planed 1 12" X 5 1/2 X 66" long With a 3/4" Strait bit , the wood was twisted and warped , The end product was 1 1/8" , 1 1/4" , 1 3/8" thick I made 6 , to make a railing 4 1/4" thick 1 1/8" + 1 3/8" + 1 1/2" = 4" This is 1/4" of but is not notisable 1 Week average 7 hours a day , I filled my chop vac 2 1/2 times , The important thing is that my custemer is satisfied !


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## GeorgesG (Mar 19, 2012)

GeorgesG
Good luck , I planed 1 1/2" X 5 1/2" X 66" long With a 3/4" Strait bit , the wood was twisted and warped , The end product was 1 1/8" , 1 1/4" , 1 3/8" thick I made 6 , to make a railing 4 1/4" thick 1 1/8" + 1 3/8" + 1 1/2" = 4" This is 1/4" of but is not notisable 1 Week average 7 hours a day , I filled my chop vac 2 1/2 times , The important thing is that my custemer is satisfied !


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