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View Full Version : Jointer testing and set-up: What tools / gauges do I need?



Allan Speers
11-24-2019, 6:50 PM
I'll soon be buying a used 8" jointer, and I'm trying to determine what tools I'll need for a full check, & later setup. This would include testing flatness, twists, etc. The tables, the fence, and whatever else.

I know the basic concepts, but I can't figure out which exact items are best, to get good accuracy without wasting money on uber-machinist type stuff. Can anyone simply post a list, of what they would recommend I buy?
(And maybe even some ulrs for recommended instructional videos?)


thanks a ton.

Paul F Franklin
11-24-2019, 7:34 PM
The woodcraft 38" straightedge is decent for the money; no starret, but mine is flat within a thou or less over the length. An even longer straightedge would be helpful but good ones get pricey fast. The Oneway gauge will let you check the fence pretty well (just using the precision ground right angle sides) and runnout of the head with the indicator. You won't need it to set the knives if you go shelix, but it would still be useful for setting the outfeed table height. Of course you'll need feeler gauges, especially the thinner ones.

David Kumm
11-24-2019, 7:56 PM
A good extruded 6' level, feeler gauges, and a Oneway base with dial indicator. Dave

Doug Dawson
11-24-2019, 8:19 PM
A good extruded 6' level, feeler gauges, and a Oneway base with dial indicator. Dave

Longer levels tend to sag, which could mask the sagging of the tables. Better to get a shorter (4 foot?) straightedge, even a Borg will do (test the straightedges against each other by flipping them back and forth and choose one that causes the least error, etc.) Test each table separately, and then try to make the tables _even_ (zero cut depth) and measure across them. That should give you a general idea of whether you have something usable.

FWIW, a parallelogram jointer's superiority is for when you want to _correct_ an out-of-line condition. Shimming large dovetail jointers is an experience nobody would relish.

Mel Fulks
11-24-2019, 8:21 PM
I like the 4 foot Harbor Freight aluminum rules. Just pick up two of them ,in store , and test...in store. Surprisingly accurate.

Bill Dufour
11-24-2019, 8:51 PM
I like the 4 foot Harbor Freight aluminum rules. Just pick up two of them ,in store , and test...in store. Surprisingly accurate.


You need to test three at a time all against each other.

Allan Speers
11-24-2019, 8:55 PM
Thanks, guys.

So no winding sticks or similar?

Doug Dawson
11-24-2019, 9:08 PM
Thanks, guys.

So no winding sticks or similar?

Winding sticks are for the flea. But that flea has littler fleas upon him. And so on ad infinitum.






(IOW, for a reference stock processing tool, no.)

Allan Speers
11-24-2019, 9:25 PM
Huh?


How do you check for twist?

Doug Dawson
11-24-2019, 9:33 PM
Huh?


How do you check for twist?

Diagonal check. Sorry if you missed the point that this is an iterative process of stock prep, where the tool you start with defines what you are ultimately able to achieve re "straightness" or whatever.

Allan Speers
11-24-2019, 9:58 PM
I don't even know what "iterative" means. Lol....


BTW, is the this Oneway guage I want?

https://www.amazon.com/Oneway-2289-Multi-Gauge/dp/B0002SA98I

Any other accessories I should get? (I wouldn't mind being able to better tweak the rest of my shop, as well.)

David Kumm
11-24-2019, 10:03 PM
Have several long levels and measure them against a Pinske edge. None sag. An 8" jointer has a relatively short bed so the tables are pretty easy to make parallel. Dave

Doug Dawson
11-24-2019, 10:50 PM
Have several long levels and measure them against a Pinske edge. None sag. An 8" jointer has a relatively short bed so the tables are pretty easy to make parallel. Dave

Well, great. I don't have any "Pinske edges", I only work with Starrett (NIST traceable) as an absolute reference, and as a material, longer (typically aluminum) levels do indeed sag end-to-end, placed on edge. Not the greatest reference. There are cheaper ways of checking a jointer, as I pointed out. The typical 8" jointer will be 7' long, so...

Paul F Franklin
11-24-2019, 10:54 PM
BTW, is the this Oneway guage I want?

https://www.amazon.com/Oneway-2289-M.../dp/B0002SA98I

That's the one I have. Works great for setting jointer knives and outfeed table height, but I find I reach for it anytime I want to square a fence to a table, or check bandsaw table to blade, etc. It's wide enough and heavy enough that it's easier to use for those checks than an engineer's square, for example.

Allan Speers
11-24-2019, 10:56 PM
That's the one I have. Works great for setting jointer knives and outfeed table height, but I find I reach for it anytime I want to square a fence to a table, or check bandsaw table to blade, etc. It's wide enough and heavy enough that it's easier to use for those checks than an engineer's square, for example.


Thanks, Paul.

Can you also use it to set up a planer?

- Or would this one be more versatile?

https://www.amazon.com/Woodstock-W1218A-Rotacator/dp/B0000DD0P0/ref=pd_cp_328_2/141-6766909-0799204?_encoding=UTF8&pd_rd_i=B0000DD0P0&pd_rd_r=882e4650-3cf4-47f0-a90c-894b13723f08&pd_rd_w=psqu6&pd_rd_wg=IVyMP&pf_rd_p=0e5324e1-c848-4872-bbd5-5be6baedf80e&pf_rd_r=P858VNED6CDXAR7HNF00&psc=1&refRID=P858VNED6CDXAR7HNF00

Paul F Franklin
11-24-2019, 11:16 PM
You could use it on a planer if there is a good flat reference surface adjacent to the cutterhead, but I'm guessing most planers don't have that. I know my lunchbox planer doesn't.

I don't think that other tool you link to would be any more versatile. It lacks the nice machined square back end of the oneway. The amazon photo of the oneway cuts off the part of it I'm referring to, you may want to look at it on the oneway site.

Thing is, once you have a decent dial indicator (the one that comes with the oneway seems decent) there are all manner of bases with adjustable beams that will hold it and position it to make useful measurements.

David Kumm
11-25-2019, 12:44 AM
Brian lamb at lambtoolworks.com makes a nice indicator stand similar to oneway. A dip across the width of the table is a problem as is out of co planar if looking at a wedge type jointer. Problems near the head are worse than being out of flat at the ends of the tables. Cheaper wedge jointers with 6' tables can be out of flat up to .010 and still considered within spec. My DJ 20 has an .008 dip on the end of the infeed and a few thou at the lips. My old larger jointers much less but both can make flat boards. I'm not disagreeing with any of Doug's methods . When you set the straight edge on the outfeed and bring up the infeed, there isn't much unsupported length to be concerned with. Dave

Michael A. Tyree
11-25-2019, 7:01 AM
First off, I am 76yrs old, served an 8,000 hr apprenticeship as an industrial mechanic/millwright and worked in mechanic pre wrenching jobs for yrs, so I know my way around machines. I've also been a helo mechanic, car & MC mechanic too, retired auto tech teacher.
Meanwhile I'm a lifelong woodworker. I use two tools to set the blades on my 8" jointer- a high quality carpenters level and a 12" Starret scale blade. I do own dial indicators w/magnetic bases and much much more but those two tools serve me well in the end. My jointer is an old one from the defunct Indiana mfg., and has a 1hp motor thats a leftover from my Grandfather's stuff-it's about 3X's the size of modern motors but in practice it gets to speed quickly and that huge armature once spinning is ideal for the machine. meanwhile, my Delta 14" bandsaw which is about 45 yrs old is on the 3rd or 4th motor and maybe the 3rd switch!

Brian Holcombe
11-25-2019, 7:47 AM
Doug is certainly correct in that checking crossways will show twist, that said in my opinion there is nothing wrong with using winding sticks, it will make a twist very obvious. If the table has a twist in it, I would certainly pass on it.

Check your winding sticks against a reference, like a granite surface plate and verify them to be accurate. Winding sticks out of parallel will have you thinking everything in
the shop is twisted.

Personally, I would want a straight edge at least as long as one table, use it to verify that the tables are flat (or otherwise) then use it to make them parallel to one another.

I don’t use a one way gauge for outfeed table height, I just flatten a board’s edge, then set the height to the point at which rotating the head (by hand) will just barely pull the board. This is likely .001-.002” above the outfeed.

Outfeed too high will have the board your jointing bump into the table edge as it goes over, outfeed too low will cause snipe at the end of the board.

Brian Holcombe
11-25-2019, 8:07 AM
A carpenter’s level is not a straight edge. Consider that a Starrett straight edge 72” long has a 3.15” x .276” section and I believe they are hardened steel. They are accurate to .0002”/ft to over 72” that is .0014”

A Stabila level is rated accurate to .5mm/m so over 72” that is .036”. Ok for checking door frames but pretty useless for checking machinery.

Robert Hazelwood
11-25-2019, 9:28 AM
For checking a prospective used jointer I would just be checking that each table is flat and not twisted and to see if there are gross errors in table alignment. So a good ~36" straightedge and some feeler gauges are the main tools. Lee Valley sells a nice steel 36" straightedge, supposed to be +/- 0.0015" over its length. You can check the face of the fence with this as well. The rest of the inspection would be trying to assess the state of the cutterhead and motor bearings, listening for strange noises or electrical issues, etc.


For setting up a jointer you've taken home, you need those tools above plus a dial indicator and base, and a good square. And to really check the table alignment, you need a longer straightedge. Brian pointed out the problems with levels, and the machinist straightedges that are long enough are really, really expensive. The best solution for me is to make a pair of wooden straightedges, match planing them with a jointer plane then flipping over onto the other and checking for gaps. The straightedges need to have some depth to them to stay rigid enough to plane accurately, and you need to support them well while planing. If you do that then it isn't too hard to get them to 0.001" or less. I think the ideal shop-made straight edges would be a wooden I-beam, similar to a floor joist. Two 1x1 hard maple strips with a 1/4" BB or MDF web and a total depth of 6 or 8 inches.

As for the dial indicator, I basically use the method Bob Vaughan shows in this video: https://www.youtube.com/watch?v=VRnrWOwun68

He just uses a regular magnetic indicator base. That works but my indicator stand is not the best and I don't completely trust it not to move during the process, so I made a sort of wooden version of the Oneway gauge out of a block of SYP. It has three points of contact on the bottom and enough mass to stay in place while I move the knives/cutterhead. Indicator mounts to it with a wood screw. Works great. The Oneway gauge looks really nice as well.

You want to get a broad convex tip for your dial indicator. I ordered a set of tips off of amazon, they are kind of a joke tbh but one of them works well enough for this. I would just order an actual starret tip from MSC or someplace like that.



Bob Vaughan made a video for planer knives as well: https://www.youtube.com/watch?v=uSM7Jrg34a8

Alan Schwabacher
11-25-2019, 10:56 AM
I recommend "Care and Repair of Shop Machines" by John White. He not only shows how to adjust machines including the jointer, he also shows you how to make test bars to adjust flat and parallel to high precision. These bars are simple and cheap, and while they work to set jointers, they are not straight edges useful for other purposes. The idea is to get three test points that are in line accurate to .001" or better, and to use these judiciously to align your jointer tables. You need a set of three bars at each size: one set the length of your entire jointer span, and another the length of each bed. The trick is to get the points in line without an expensive reference, and he shows how to do that.

This is not to say that machinist quality tools are not useful, but that if setting up the jointer is their only planned task, you may be able to get good results while avoiding paying for them.

Brian Holcombe
11-25-2019, 1:21 PM
A key point is that the OP intends to inspect a machine and then determine if he wants to purchase it. Four points is excellent for setup but it won’t tell you much when used for inspection.

Two tables can be adjusted to agree on four points even if they’re not flat, but they may not joint a board well.

Allan Speers
11-25-2019, 8:08 PM
Great stuff, guys. thanks. And Alan I'll definitely check out that White book. From what you describe, that's some kind of "deluxe winding stick" method, using 3 sticks. I'm very curious about this.


My big problem is what has been discussed at the end here: finding a reliable straight edge. I have a number of long carpenter levels, but none of them butt together without any daylight in-between.

I was thinking about getting one of the Lee Valley units, as they are reasonably priced, though $122 is still a bit steep. (I assume it's the same one Robert mentioned)
https://www.leevalley.com/en-ca/shop/tools/hand-tools/marking-and-measuring/50074-veritas-aluminum-straightedges

I'm also going to check my EZ track rails. They are thick aluminum. Maybe one of them will work

I also am wondering if one could possibly use a laser level? I have a pretty expensive one, and it can be locked so it doesn't have to be level. I'm thinking maybe putting it on a tripod, then getting the output right at the level of one table, & shining it across. You get the idea. Well, maybe......

Edward Dyas
11-25-2019, 8:40 PM
I'll soon be buying a used 8" jointer, and I'm trying to determine what tools I'll need for a full check, & later setup. This would include testing flatness, twists, etc. The tables, the fence, and whatever else.

I know the basic concepts, but I can't figure out which exact items are best, to get good accuracy without wasting money on uber-machinist type stuff. Can anyone simply post a list, of what they would recommend I buy?
(And maybe even some ulrs for recommended instructional videos?)


thanks a ton.You don't need much. You might lay a level across both tables and see if they are coplanar. Personally I've never seen one that is not but it wouldn't hurt to check. From there just make sure each of the knives is level with the rear table all the way across the width. If one is sticking up just a little it will be doing all the cutting. All you do to check the knives is lay a steel rule across the rear table edgewise and gently rotate the knife so it barely touches the ruler. If you get all the knives set like that it should cut nearly as smooth as a hand plane.

Tom M King
11-25-2019, 9:17 PM
Copying, and pasting this from a thread I started called: Quick and Easy Setting Straight Jointer Knives on another woodworking forums.
I think I forgot to mention that the first thing I do with a jointer is take the springs, and jack screws out. I change jointer knives fairly often. They are sharpened by hand on my Sigma water stones to as sharp as I can get them, which is way sharper than they come back from any sharpening service. Of course, they don't stay that sharp long, but if I have a few hundred small parts to run, as in making a bunch of window sash, it saves a lot of time in the long run, to finish off the jointer. This process takes just a few minutes. You can feel less than a thousandth of an inch.
I do have a pretty fair assortment of indicators with various stands, and they do get used for planer knife setting, and planer adjustments, but I can do at least as good of a job with this simple method. You do have to be aware of wear on the wooden strip in the process, and only use clean, unscalloped sections for the final feel.

You can see the machine marks on that test piece of wood, if you look closely, and have a large monitor. It was not fed unusually slow, but not slammed through either. Light is reflection from a North window.

Last picture shows all the tools needed for precision knife setting. The right angle pick is to pull a knife up, if it starts too low, or you push it too low, for some odd reason.


Tools needed: angle hook pick to pull knives up above final position if they drop too low when putting them in behind the gib
wrench to fit gib screws
strip of the hardest wood you have. I don't know what size this piece of Boxwood is, but it's a good size for the job. A wood not so hard would need to be a little thicker so it could push the knives down without such a large dent sliced into it.
The trick is to install the knive so the gib will hold it where you put it, but not slide up, or down without help. Tighten until you feel a little resistance, and then back off a hair.
Wrench starts on one of the center gib screws, and rotates the head back and forth. Tail end of the wood stays down on the outfeed table, so it can't possibly push the knife down too far. Rotate the head back and forth while gently pushing down each end of a knife. When you can rotate the head, and feel the knife brushing the wood, ever so lightly, on each end, tighten that screw that the wrench is on, and then after checking both ends again, tighten the other screws.
Same for the other knives. Keep moving the position of the wood so the knife is not resting in any tiny groove. Takes maybe 20 seconds per knife, if you don't get in a hurry.
No need to measure anything, or how far the knife can pull the wood.
Test run a piece through the jointer. Some people I've taught this to end up with a little snipe. That's why jointers have adjustable outfeed tables. I use that adjustment a lot more than most people I expect. One reason some like to leave the knives proud of the outfeed table plane is so as the knives wear, you can still straighten a board. I just adjust the table at that point, but run it back up the next time I set the knives so it doesn't eventually get lowered too much. To adjust the outfeed table, learn which way it goes while you have knives out, so you don't have to chase it with fresh knives.
I wouldn't mind having one of those Byrd heads, but the time necessary to change those cutters would be a little maddening for me. This way, if you need to run finished sides on the jointer, it doesn't take long to change a set, and saves a lot of time sanding.
Picture of wood is piece of Cypress run against the grain. Freshen up the edges of your setting strip while the knives are fresh, so it will be ready to go next time.
https://www.woodtalkonline.com/uploads/monthly_2019_08/IMG_1922.thumb.JPG.efabedb628d635e642ac8d0d4ad40bd e.JPG (https://www.woodtalkonline.com/uploads/monthly_2019_08/IMG_1922.JPG.32c19f0fb9ef1251e1258920338d8e29.JPG) https://www.woodtalkonline.com/uploads/monthly_2019_08/jointerknivesinstall.thumb.jpg.748f40ba3679681b8ac 16b70813e5102.jpg (https://www.woodtalkonline.com/uploads/monthly_2019_08/jointerknivesinstall.jpg.c38d3c44ccb07a46c5f91880b e972977.jpg)https://www.woodtalkonline.com/uploads/monthly_2019_08/IMG_1927.thumb.JPG.cdf9fe574edd18b03c917f418a0d25b 4.JPG (https://www.woodtalkonline.com/uploads/monthly_2019_08/IMG_1927.JPG.1dba63e2c8348f68b83e2dc7f3f366e2.JPG)
https://www.woodtalkonline.com/uploads/monthly_2019_08/IMG_1921.thumb.JPG.176dc1b27e668e3affcf02ad37af6d5 4.JPG (https://www.woodtalkonline.com/uploads/monthly_2019_08/IMG_1921.JPG.abd8cdf1bb39c5f2ef5d85efb7d21c0f.JPG)

(https://www.woodtalkonline.com/topic/30242-quick-easy-setting-straight-jointer-knives/?do=showReactionsComment&comment=397682&reaction=1)

Tom M King
11-25-2019, 9:48 PM
Some will ask how many thousandths proud are the knives after I set them like that. I measured it a long time ago, with one of my dial indicators, but since it doesn't matter a bit to me, I forgot.

These window sash have every part finished on two sides off the jointer, and not touched again. There were 38 of them total, and they are exact reproductions of the original ones that only parts were left of. They're in an 18th Century museum house. The inside of the Heart Pine sash were not painted, so the surface did matter. Everything else wooden in there is hand planed, but it wasn't worth the trouble for the sash.
http://historic-house-restoration.com/images/DSC_0030_2959.JPG

Andrew Hughes
11-25-2019, 10:41 PM
Excellent work Tom.

Mark Hennebury
11-26-2019, 8:39 AM
Nice work on the windows Tom, I need to get the courage to start making the replacement windows for our 115 year old house, i have been avoiding it for several years.

Tom M King
11-26-2019, 8:46 AM
The full process should be in pretty good detail, with pictures, on my website.

edited to add: The ones in that picture haven't been pegged yet. Just like the old ones, I don't use glue. That allows you to replace parts 200 years (or more hopefully) into the future, by driving the pegs out. Picture is 1798 sash that had two broken glazing bars.

http://historic-house-restoration.com/images/windows4_001.JPG

Mark Hennebury
11-26-2019, 9:06 AM
With a straight edge.

A straight edge and the understanding of how to use it is all you need.

Ideally you would have five precision buttons. they would all be the same thickness, you can anything that is the same thickness, bearings, tool steel, dimes, pieces of paper.. whatever in a push.
And a set of feeler gauges if you have them, or paper if not.
Set one button on each corner and one in the center of the table that you want to check.
Place your straight edge across the diagonals resting on the three buttons.
On a flat surface the straightedge would touch the three buttons across diagonals.... in both directions.
If it doesn't then you table is not flat. and you can see where and how it is not flat.
With feeler gauges you can precisely measure how much out your tables are.



Huh?


How do you check for twist?

Allan Speers
11-26-2019, 4:39 PM
A related questiON:

Let's say I find that the tables are a bit off. And being picky, I want them a little flatter.

Assuming I have a very good reference, like the Lee Valley straight edge (I think I'm going to order one)

IS IT POSSIBLE TO CAREFULLY HAND-SCRAPE A TABLE, to something resembling machinist precision?



- Or is that akin to jumping off a high cliff, during a hurricane, into an ocean full of rabbid sharks?

Brian Holcombe
11-26-2019, 5:06 PM
A related questiON:

Let's say I find that the tables are a bit off. And being picky, I want them a little flatter.

Assuming I have a very good reference, like the Lee Valley straight edge (I think I'm going to order one)

IS IT POSSIBLE TO CAREFULLY HAND-SCRAPE A TABLE, to something resembling machinist precision?



- Or is that akin to jumping off a high cliff, during a hurricane, into an ocean full of rabbid sharks?

Yes, if you're willing to buy a large, recently inspected granite surface plate and scraping tools. Theoretically scraped surfaces are the highest precision flat surface, in practicality that depends on whose doing the scraping and the caliber of inspection tools they have.

Andrew Hughes
11-26-2019, 5:10 PM
I say yes it is possible. But you will need a second reference surface bigger and flatter then the table your scraping.
Plus you’ll need more tools,time and skills you may not have.

I hand scraped my Fence for my tablesaw it took a most of a day and lots of elbow grease.

Good Luck

Allan Speers
11-26-2019, 5:12 PM
Yes, if you're willing to buy a large, recently inspected granite surface plate and scraping tools. Theoretically scraped surfaces are the highest precision flat surface, in practicality that depends on whose doing the scraping and the caliber of inspection tools they have.

I was thinking more of testing carefully with that precision straight edge, (and maybe Mark's "3 button" idea above, or precision winding sticks,
or....) Then marking all the high spots, and just SLOWLY taking things down. Is that viable?

Of course, if there's a low spot, I'm sunk, but I figure small low spots probably wouldn't affect lumber milling much, anyway. (unless right by the cutterhead.)

Doug Dawson
11-26-2019, 5:18 PM
A related questiON:

Let's say I find that the tables are a bit off. And being picky, I want them a little flatter.

Assuming I have a very good reference, like the Lee Valley straight edge (I think I'm going to order one)

IS IT POSSIBLE TO CAREFULLY HAND-SCRAPE A TABLE, to something resembling machinist precision?


It's theoretically possible, and I'm sure they've done this in North Korea, at the instructions of Dear Leader. But for all intents and purposes in our country, it's probably not worth it. Better to suffer thru the use of shims, in the hope of getting the "global" alignment right.

Brian Holcombe
11-26-2019, 6:40 PM
I was thinking more of testing carefully with that precision straight edge, (and maybe Mark's "3 button" idea above, or precision winding sticks,
or....) Then marking all the high spots, and just SLOWLY taking things down. Is that viable?

Of course, if there's a low spot, I'm sunk, but I figure small low spots probably wouldn't affect lumber milling much, anyway. (unless right by the cutterhead.)

I can’t imagine this approach doing anything but frustrating the user.

This type of thing works for hand planing becuase the hand plane itself is a long reference. Scraping is done with a small scraping tool which has no reference surface so i imagine it would be similarly difficult to flattening a board with a carving with a spear plane (long handled Japanese slicing tool), yes it can be done but without a big reference surface you may just be causing dips.

Tom M King
11-26-2019, 6:45 PM
If it's old enough to have been from the time when they left castings out in the weather for several years before machining them, and has not been in a production shop with a feeder, I'd expect them to be okay.

Allan Speers
11-26-2019, 10:31 PM
If it's old enough to have been from the time when they left castings out in the weather for several years before machining them, and has not been in a production shop with a feeder, I'd expect them to be okay.


Sadly, it's a 1980's Taiwanese Dayton. That's why I'm so concerned.
But like I said, the price is very good. And it has a USA 1.5 HP motor. And no rust. And one hobbyist owner since new. So.....


I know, I know, I should have jumped on that 8" General when I had a chance. Sigh ...

Doug Dawson
11-26-2019, 10:53 PM
Sadly, it's a 1980's Taiwanese Dayton. That's why I'm so concerned.
But like I said, the price is very good. And it has a USA 1.5 HP motor. And no rust. And one hobbyist owner since new. So.....


I know, I know, I should have jumped on that 8" General when I had a chance. Sigh ...

Just start using it, then. Everybody needs a scapegoat. :^)

Paul F Franklin
11-27-2019, 9:31 AM
If it's operating, another approach would be: take a wide flat board a few feet long with you (you know, from Home Depot's flat board section:rolleyes:) and take a few passes and see if it's still flat....

Robert Hazelwood
11-27-2019, 9:58 AM
I think you could do the scraping with a straight edge as your main reference. You won't be able to get ten-thousandth accuracy without a large plate, but one thousandth might be doable. A smaller reference plate could be used to assist to find local low spots.

There is a technique scraper hands sometimes use called "blind" or step scraping, I think. This is kind of a roughing technique to get the workpiece to sit flat on the surface plate before beginning the spotting and scraping process. Suppose you have a concave surface along the length, measure the extent of it. Say it's 0.005" deep at the center. Divide the surface into a number of equal parts along the length with a marker. Knowing that a scraper removes about a third to half a thou per pass, on the outer divisions need something like 10 passes, and the center section just one pass, the increasing numbers of passes for the intermediate sections as you move away from the center. Each pass is just an even series of strokes across the surface, keeping a consistent pattern. A similar concept to tapering a stick with a handplane.

If you have a lot of time on your hands I think that could work. A true madman might even create his own woodworking surface plate, maybe a 1'x4' MDF torsion box with the top flattened to 0.001" with planes/sanding blocks. Seal it good and spot with that.

A handscraped finish should have an additional advantage in reduced friction compared to a surface ground table. But really if your jointer tables are bad enough to cause problems then just take the top assembly to a shop that has a big surface grinder or blanchard machine and get the tops ground together while attached to the center dovetail part. That way you get flat tables and guarantee parallelism (which you could not easily do with the shadetree mechanic scraper method). An 8" jointer shouldn't be too expensive to get ground, and afterwards it should be better than any new jointer.

Mark Hennebury
11-27-2019, 6:49 PM
You can do it, and you don't need any special tools, you can improvise and use whatever you have. You just have to ask yourself if it's worth it.

The sliding table on one of my tablesaws was out by 0.020" , so i got it to less than 0.002" with a disc grinder and a die grinder using a good straightedge. The saw is at least usable at those specs, when i get around to rebuilding it i will handscrape it in on the surface plate, but then i have to do the guide tracks and mitre slots etc, Its a lot of high precision ( time consuming ) work. Fun if you enjoy it and have the time.

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Allan Speers
11-27-2019, 9:45 PM
Just start using it, then. Everybody needs a scapegoat. :^)

LOL.


Built-in excuses can be very helpful !


I got a good dial indicator package, plus I ordered that LV straight edge today. - It's actually only 99 bucks in US dollars, so that' really not bad at all. I guess I'm good to go, for the moment.


Thanks, all. Great stuff.

Allan Speers
12-10-2019, 1:08 AM
Well, that 8" Dayton jointer is in my shop.

What a nightmare getting it in my truck.
(Hint: Don't forget a set of large metric allen wrenches! Oh, and don't pick up heavy machinery in the pouring rain.)

Maybe I'll post all the things that went wrong in a separate thread. It might save some future shlub the agony I just went through. Couldn't take it apart (the fence only comes off with an allen wrench & the tables won't come off if the fence is still on it), broke the fence mount picking it up with the hoist, had to slam on my brakes on the way home and broke the windows in both my cap and my truck, then the broken window let rain pour onto the tables for the 2 hour ride home & now they're covered in surface rust....
------------

BUT THE GOOD NEWS IS: :)

Thanks to all the ideas here, I was able to determine that the tables are dead-flat (not even a .005 gap anywhere) coplanar, no twist, etc. - Same for the fence.
The head is perfectly parallel and the bearings feel like new.
Not bad for 1987 Taiwanese.

The US Dayton motor runs great, the cutterhead bearings seem perfect, the tables move easily .....

I have to weld that broken fence mount before I can try it here, but it worked great at the sellers house. It seems like a VERY nice machine, actually. I think Grainger must have had pretty tight specs back in the day, and used an ISO 9001 factory.

I'm going to do a ground-up restoration, as most of the bolts are somewhat rusty. (I also hate the color.) When I do that, I'll try to do a write up on this model, with pictures. It's kinda' your standard Taiwanese Delta clone, but has nicer fittings than some of the others I've seen. (Bridgewood, etc) Plus, of course, it has those lovely table extensions.

It could be a great choice for guys on a tight budget, like me.
(Even tighter, now that I have to replace two broken windows. :( )

Paul F Franklin
12-10-2019, 9:17 AM
Oh man! Can't wait to hear the whole story....once the sting has gone away.... Glad the jointer turned out to be a good one at least!