How flat is flat?

[Greg Hairston]

Im about 80% done with my new bench and was wondering how flat is flat. Should this be glass flat or not warped flat. I have my bench reasonably flat. The more I play with it the worst it gets. Just wondering how anal should I be.... Big problem is I did not pay attention during glue up. I have grain going different directions.... Big lesson learned. So it is hand plan and ROTEX and it is getting to the point where I am wondering what is the return on investment here. Any way here are a couple of pics of the bench and some new toys I have acquired in the past weeks. There are more but I will save them for another day.

I still have to put on the end caps for the bench and Vise and I have a front vise I am installing this weekend.



Greg H

[Roy Wall]

Greg,

Nice Bench!!!! Looks impressive and solid!!!

I am not qualified to answer you question because I'm too much of a rookie - but I will try and willingly follow this post for my inaccuracies.....do you have a LA jack plane or #7....

I think the LA jack will assist with the grain problem and will also help flatten better - the smoother is too short.

[Steve Wargo]

It should be the absolute flattest surface in your shop. It does make a difference, in everything from planing to glue-ups. Don't stop until it's perfect. You'll be glad you did. Now with that in mind, please don't ever look at my decrepid bench.

[Roger Bell]

My view is this: Don't be too hard on yourself. If you really feel that it is indeed reasonably flat, then it is probably flat enough for now. All you can do is to plan to do your best considering the capabilities of your tools in your hands. And to be willing to settle for a bit less perhaps than the perfection that you had hoped for... and to be willing to strive to do a better job next time (ie. make fewer of the same kinds of mistakes...whatever those might have been this time). No more can be asked or expected from anyone.

The bench top is not made of granite, but of wood. The top can always be surfaced again....and it will indeed need occasional "flattening" from time to time no matter how perfect or imperfect it may be at this moment. But that can be a project for a later day when your energy is renewed and you determine it is in fact needed. Realize also that each project has its "patience quotient"....and perhaps it may be time to just keep moving along towards completion. I guess that my point is that this a value judgment that you alone are qualified to make.

[Tim Sproul]

I agree with Steve....you want that top surface as flat as you can muster. But I also agree with Roger in that you've got to stop working on your tools (your bench is a tool) and start building stuff.

If those are the only planes in your arsenal, that is a good portion of your flattening woes. Give Steve Knight a ping and tell 'em you need a nice 30 inch long plane.

[Derek Cohen]

How flat is flat?

- can you plane flat boards (and at what lengths) without them rocking?

- can you clamp boards across the bench securely, and flat to the table?

- are the edges good reference points for 90 degree angles?

- can you sight down a board with winding sticks secure in the knowledge that you are measuring the angle of the board and not the angle of the table?

Any others?

Nice looking bench!

Regards from Perth

Derek

[Mike Holbrook]

I am a rookie too but...I believe you will find that a longer Jointer type plane will help with getting that long surface flat. Others have touched on this but as I understand it the longer plane bed gets out imperfections that the shorter planes go around, makes sense if you think about it. Another factor is the angel of the plane iron. A York pitch, 60 degree angel, is better at dealing with difficult, hard grain.

[John Hart]

Greg, I built my benches the same way...You're going to love them! In my humble opinion, get them flat....Don't go for glass because over time they won't be glass anyway...but don't have raised spots and avoid a "dome". Using a plane or a beltsander on a rocking piece of wood is a real pain in the neck (literally). And, many times, gluing requires that you rely on a reasonably flat surface. As time goes on, there will be glue and finishes deposited, knicks gouges, scratches. Going for glass now is a waste of good project time.

[Greg Hairston]

Question about technique.
I have a Record #7 Plane that I just tuned up. The bench seems to have a slight dip in the middle.
Would it be best to plane perpendicular to the grain or should I concentrate with the grain or at an angle.

I am thinking perpendicular because I can feel when I get the low spots. Once I have it flat that way then I can shoot at an angle to work the flatness for the length of the bench... Your thoughts...

Greg

[Mark Singer]

Greg,

I would try to find a wide drum sanding service in your area! For about $20 you will save a lot of time and get it perfect. Otherwise diagnol is easier to plane...but, you have to bring it all down to the level f the recess,

[Alan Turner]

Greg,
Looks like you are coming along nicely on your bench. Yes, in answer to your question. You should plane cross grain to level out the valleys, then at a 45, then with the grain. The flatter the bench, the better, since most use the bench as a gluing platform.
As a side note, the pattern shop where I am buting the used tools used what they call "layout" tables, which are milled steel, dead flat, and they were used as the table to glue up the patterns which had to be quite precise. The sizes varied in this shop, and some were smaller, and sat on regular benches, but there were some full sized ones, perhaps 36 by 60 or so. Boy, are they heavy!

[Greg Hairston]

As I sit here with SWEAT dripping off my forehead I say NO!!!! to you and your evil ways MR. Singer. That would be too easy. We must do thing the way our ancestors did them.

Really that would have been the best way to go about it but I am too far along now to do that (read piss poor planning). I would have to rip the aprons off and remove the vise and vise supprorts. So it looks like manual labor is the way. I just spent 30 mins flattening a 2 in section across the bench. Since the bench is approx 80 inchs long I have about 40 hrs of work ahead of me unless someone has a better idea..... I purchased the Rotex for this but it just does not seem to do the trick. The plane seems to be a bit faster and I will touch up with the ROTEX......

Alan you are welcome to fly down and give me some first hand instruction at this. Do you like Barbeque????


Thanks for the input..

[Roy Wall]

As I sit here with SWEAT dripping off my forehead I say NO!!!! to you and your evil ways MR. Singer. That would be too easy. We must do thing the way our ancestors did them.

Alan you are welcome to fly down and give me some first hand instruction at this. Do you like Barbeque????


Thanks for the input..

Ha Ha!! Keep at it Greg.......The time will pass - and you'll be glad you did it!!

[Steve Wargo]

Greg,
30 minutes to flatten a 2" by 80" section is way too long. You should be able to get the whole top flat in an 60 to 90 minutes. I say flat. It's O.K. to take a course cut in this process. Then just lighten up on the cut to finish it off. maybe another 45- 60 minutes. I wouldn't really concern myself with the overall smoothness of the top in the flattening process. You're really just looking to get it flat. You may need to scribe a line around the outside to achieve this. A jointer plane is really needed to make this easier. I imagine you'll plane all day and not get it flat with a smoother. After it is flat (not smooth) go over it with the jointer with a really light pass to make it smooth. If necessary you can touch up the surface with a scaper to clean up any tearout, but it's not really required. Hope this helps.

[John Hart]

Geez...The hard way. Even though I do everything the hard way (foolishly), I must be a hypocrit and suggest an easier way.

In my young days, an older gentleman took a large square and laid it on the table top then peered at the gaps it showed with his eye level to the table. Using a pencil and moving the square along the surface, he scribbled on all the high spots for the full length of the table. Then with his plane and a belt sander, he removed the pencil marks...then he did it again. The table was flat in 2 hours.
It takes me longer because I'm an impatient fool...But it works and I still do it and think about him today.

good luck!