How To Flatten A 12" Jointer Table?

[Derek Arita]

I have a 12" Mini Max jointer/planer that has a top that is not as flat as I'd like. In places it's out .010. Anyways, it seems like a big job to flatten the top, as I've never had to have it done on any other machine I have. I/ve heard that I can take the machine to a machine shop and have it done.
How do I find a good machine shop that can do it? Do I remove both tables and take them in? How do they flatten the top? By the way, I'm in the Sacramento, CA area.

[Brian Brightwell]

A surface grinder is the tool of choice. It would take a good size grinder.

As a side note. The throat plate on my Laguna table saw was warped. My first thought was a machine shop with a surface grinder. But then I put it on a backing board and ran it through my wide belt sander. An ink marker on the surface indicated the progress. I made very light passes and it took awhile but a lot less time than taking it to a machine shop. By the way the throat plate on a Laguna is rather large,

[Ellery Becnel]

Derec, is the .010 dip across both tables or is it in just one table? Is it a dip in the middle, or low on one end? If it is low on one end it might be possible to shim the mounting portion to adjust? If it is a dip, then it would have to be disassembled. They will charge you more than you can imagine. It would have to be surface ground. Normally the machine has a magnetic table to hold plates that need to be parallel within .0001. Some have a vise that can hold iregular shapes. There is a large precision grinding wheel that is above the part. The table strokes from left to right and front to back with the part. The spindle with the grinding wheel moves downward in .0001 increments. The table is flooded with coolant so the wheel and part does not get overheated and explode. It will probabbly need to be an industrial machine shop. This is not a cheap job to do. If a smaller shop can do it than you might save some money. If you know any machinist in the area, you might want to talk to them for local help. I hope this helps. If it can be adjusted it will be better for you.
Good luck Ellery Becnel

[Dan Forman]

I have a 14" MM J/P who's table is not as flat as I would like either, but have managed to adjust it so that it really doesn't seem to matter. With mine, it's mostly dips, the most significant ones are right behind the the steel lips on either side of the cutter head. I can't use the two drafting triangle method for adjusting the tables to parallel because the dip will throw the triangles off, but a 4 foot machinist's straightedge gets me in the ballpark, then fine tuning by placing two jointed edges against each other will reveal if there is any convexity or concavity present. Be sure to use a piece that is wide enough that it won't curve on it's own. I found mine produced a convex edge, so that the two edges rocked ever so slightly. Removing a .001" shim on the outfeed side fixed the problem.

Seems that for that kind of money you should get better tolerances, but with a machine so big and heavy, unless it's really out enough to cause measurable problems in your work, you're kind of stuck - especially if it's in your basement! I think a hump would be more problematic than a dip, as it would force the workpiece up, whereas the contour of a dip might be bridged if not using too much force.

Dan

[ian maybury]

Much as the guys have said - it's not the easiest issue to find a solution to.

I've been looking locally for an option to get the tables ground on my 16in planer thicknesser which has similar issues - which in my case won't seem to easily dial out without dropping tables out of plane. (it wants to cut slightly convex)

The issues i've run into reflect what the guys said. It isn't exactly a happy hunting ground for machine shops over here, and it's not that easy to find a large enough surface grinder. The other issue is that most use the aforementioned magnetic chucks, and with these it's really important to ensure that the table is very accurately supported and shimmed so that when the magnet is switched on the table doesn't deflect. This is basically a labour intensive (= potentially expensive) deal, and the risk I couldn't find a way past was that even that is no guarantee that it would be done properly - that the result wouldn't be worse than before. It's pretty clear too judging from the nature of the inaccuracies that my (milled) tables were not well enough supported and/or the feed rates were too aggressive when they were originally machined.

So it's very feasible, but has to be done right. Here's a couple of relevant pages from vintage machinery.org: http://wiki.vintagemachinery.org/JointerTableGrinding.ashx http://wiki.vintagemachinery.org/Flattening%20Cast%20Iron%20Surfaces.ashx

I've taken another tack, in that I've committed to try to scrape mine flat - encouraged (with a warning that its a skilled operation) by one of the guys on the FOG site. Labour intensive and quite hard work too - and there's scope to screw up good and proper. Be that as it may i've bought a carbide scraping tool in the UK made by Sandvik http://www.greenwood-tools.co.uk/shopscr63.html , and used it as an excuse to invest in one of the very reasonably priced Chinese made granite surface plates now around which I want for sharpening and other tool set up jobs. (shipping these is more expensive than buying them)

Some scraping information links: http://en.wikipedia.org/wiki/Hand_scraper http://www.machinerepair.com/Orders.html http://www.andersonscraper.com/Anderson-Hand-Scrapers.php#Tubular%20Scraper http://www.machinerepair.com/Tools.html There's quite a few scraping videos on Google, these give a look at the basic method of using a marking dye and a surface plate to identify the high areas: http://www.youtube.com/watch?v=JGYwJ3RQpQo http://www.youtube.com/watch?v=y2AUew5Evxc

I can't say how it's going to work out, but it's the big job for the holiday period. Wish me luck...

ian

[Phil Thien]

.010" is a lot. That is 1/10", almost 1/8". How are you measuring that?

Are you sure it is that far off? If it were that far off, I'd think you'd be able to see it by just looking at it, or running your hand over it.

[Jerry Wright]

One hundreth of an inch is not much in the world of wood seasonal or daily movement. Why the concern? That is an honest question- I don't understand the problem.

[David Kumm]

.010" is a lot. That is 1/10", almost 1/8". How are you measuring that?

Are you sure it is that far off? If it were that far off, I'd think you'd be able to see it by just looking at it, or running your hand over it.

.010 = 1/100. If the infeed is off it is much less of a problem than the outfeed. Dave

[johnny means]

Is this issue affecting your ability to joint a board? We tend to waste a lot of time and money chasing theoretical tolerances when close enough will do. IMO, Pi is 3.14.

[Brian Weick]

Blanchard Surfacing........


Talk to a machinist with a horizontal blanch grinder.



B,

[Phil Thien]

.010 = 1/100. If the infeed is off it is much less of a problem than the outfeed. Dave

LOL, thank you. What a brain-fart.

[Jeff Miller]

Total junk......unfixable I'll give ya a $100.00 for it

[Chris Fournier]

0.010" most likely isn't going to ruin your life and I would certainly want to know that my measuring tools and methods were extremely accurate. Where this 0.10" deviation exists is important. A surface grinder is not what you are after, a Blanchard grinder is the tool that would be used to remedy your table. Expect to spend some money as the set up is critical and flat is only one measurement that matters and quite frankly it is not the most important criteria; if the table comes out flat but not "square in relation to the cutter head you are in a far worse place. If you get good results from the machine I'd leave well enough alone.

[Brian Weick]

For all the money your going to spend for such a small diffrence,,,and when it's done, you won't know the difference....you may want to think twice about this.

Metal milling machines....lathes, stroke planners,vertical milling machines.......something of that nature I can see needing to get back up to specs, but wood machines ........most if not all are slightly a skewed in some way.......


I wouldn't have it done......

JMPOV,....

B,

[Sam Puhalovich]

Hello, everybody ... after 'lurking' on SMC for about 10 years ... I think that I can finally make meaningful 'pay-back' for all the information that's helped me.
I started into wood-working as I was preparing to retire 12 years ago ... I'm 74 now and still consider myself pretty-much a 'newbie' with every project being a another learning experience.
Whenever a project is finished: it seldom makes any difference what the exact size turns-out to be. However; everything is easier when the pieces are flat, square and parallel.
Having a machining background ... I don't want my equipment introducing a machined-in fault that will introduce 'difficulty' to any of the subsequent the joinery.
Last year I bought a Robland X-31 that had been sitting in various storage facilities for about 10 years. The cast iron tables stress-relieved as they aged and went out-of-flat.
I took the 12" wide tables to a shop that does car engine re-builds. They have a head-flattening machine that netted virtually dead-flat tables ... by any means that I could measure.
In the past, I had seen head-flatteners that had a grinding wheel like a vertical grinder ... this one had a 14" milling cutter. Set-up for the operation was about 5 minutes with no 'exertive' clamping used that would impart any kind of flex to the table ... far-and-away simpler then anything that would need to be done for a surface grind operation. Cutting time was less then 15 minutes per pass. The cost was $50 per table.

[Chris Fournier]

Hello, everybody ... after 'lurking' on SMC for about 10 years ... I think that I can finally make meaningful 'pay-back' for all the information that's helped me.
I started into wood-working as I was preparing to retire 12 years ago ... I'm 74 now and still consider myself pretty-much a 'newbie' with every project being a another learning experience.
Whenever a project is finished: it seldom makes any difference what the exact size turns-out to be. However; everything is easier when the pieces are flat, square and parallel.
Having a machining background ... I don't want my equipment introducing a machined-in fault that will introduce 'difficulty' to any of the subsequent the joinery.
Last year I bought a Robland X-31 that had been sitting in various storage facilities for about 10 years. The cast iron tables stress-relieved as they aged and went out-of-flat.
I took the 12" wide tables to a shop that does car engine re-builds. They have a head-flattening machine that netted virtually dead-flat tables ... by any means that I could measure.
In the past, I had seen head-flatteners that had a grinding wheel like a vertical grinder ... this one had a 14" milling cutter. Set-up for the operation was about 5 minutes with no 'exertive' clamping used that would impart any kind of flex to the table ... far-and-away simpler then anything that would need to be done for a surface grind operation. Cutting time was less then 15 minutes per pass. The cost was $50 per table.

The Robland would be much easier to set up on a blanchard grinder because it is a flat saw top which has a mounting face which is parallel to the work face (this is a bit of an assumption on my part). Jointer table do not reference of of flat parallel mounting surfaces. Impossible too do? No, but certainly much more set up involved in the OP's case than yours. Get it wrong and you have a machine is worse than when you started.

Most importantly, does this OP's machine produce straight, flat lumber? If so, do nothing.

[John Gustafson]

Is this issue affecting your ability to joint a board? We tend to waste a lot of time and money chasing theoretical tolerances when close enough will do. IMO, Pi is 3.14.

Actually Johnny according to the Old Testament, Pi is 3. It's in the description/ specifications of the columns for Solomon's temple. One cubit across, three cubits around. That was pointed out to me amny years ago by a Calculus Prof who happened to be a Hasidic jew. Outstanding instructor in the subject but he would pop up with trivia like that almost every day.

[Mark Wooden]

.010 is within tolerance for most machinery today, and like everyone has said, if it produces a good cut, don't fix what ain't broke.

I bought a Delta jointer some years ago, noticed a dip in the infeed table and with a straight edge and feeler, it measured.010 - .011. I called Delta and they said their standard tolerance was .012 so my jointer was good.

3 years ago, I needed a tilt spindle shaper.I had a limited budget and could't afford a Martin or SCM but had experience with an offsore machine that was still being produced after 20 years, so I ordered one from a machinery dealer.When I told him my Delta story and questioned him on their guarantee of table flatness, he said it was much "better"-.010" !. The machine came in at .005"+- so I'm happy, but no guarantee it will stay there. But it wasn't a hugely expensive machine either.

You can get yours set up to Blanchard or Mattison grind or you can go at it by hand, but be sure you need to and understand what the outcome- resulting flatness, surface finish, and cost- will be before you do it.

[ian maybury]

Hi Mark. The problem with maker's table flatness specifications is that it's far from necessarily the case that they are written with an eye to advising the customer (despite our tendency to presume this) of the maximum tolerance for parts within which a machine will perform correctly if set up right. Heaven knows what would happen if a machine was set up so that everything was at the outer/worst case limit of the permitted tolerance.

If we can accept that a jointer should be capable of being set up to consistently joint straight it's pretty clear that 0.010in out flat in the wrong place will make this pretty much an impossibility. It depends on what you are targeting too, and chances are that a look will show that there haven't been too many hostages to fortune created by manufacturers by the manner is which machine capability is specified either....

ian

[Carl Beckett]

I'm guessing 0.010 is within 'flatness' specification.

But a straight edge and a feeler gauge isn't capable of meausuring 'flatness'

Have no idea how a hobby shop would go about measuring flatness.....

[ian maybury]

I'm not a toolmaker Carl, but so far as I know the catch in measuring flatness is to detect twist. In that a precision straight edge (or a length of cylindrically ground silver steel of say diameter 25mm - a cheap item off the shelf from a tooling supplies place) and feeler gauges will only pick up deviations along a given line - but not relative to any defined plane. A calibrated precision spirit level (ideally) with a micrometer vertically adjusted foot at one end gets over this problem and tells a lot for small money (maybe $200) - you need to shim the table up as level as possible, and then work a defined grid in both directions. A bit fancier is a beam and dial gauge on supports sitting on a surface plate over which the table to be checked is mounted. There's various optical instruments too, but that gets into big money.

Scraping as a flattening method uses marking blue on a surface plate to identify the high spots to scrape off - you rub the table on the plate and the blue transfers to the contact points. Numerous rub and scrape cycles later your tables are flat... Measurement is necessary only to figure whether flattening is needed in the first place, and to figure how much metal needs to be scraped off. Surfaces plates have got pretty cheap these days too, and may be useful for all sorts of other jobs like sharpening and checking tools...

ian

[joe milana]

Really not enough info in the OP to give any credible advice, but it's an interesting subject. Perhaps a post over at the OWWM would get better answers.

Anyway, supposin' a guy is really determined to do something, and he picks up a large granite surface plate on ebay on the cheap. He then procedes to remove the tables, use some marking blue to determin the high/low spots on said tables, and procedes with a RO sander to flatten the tables, then fine tunes them by hand scraping, what harm could be done? (I've seen this documented in a thread over at the previously mentioned website). Remember...I'm talkin' a really determined individual...:cool: ... Shift+R improves the quality of this image. CTRL+F5 reloads the whole page.

[Mark Wooden]

But a straight edge and a feeler gauge isn't capable of meausuring 'flatness'



Oh. Well then, never mind.

[Mel Fulks]

Ian,haven't seen any where here what kind of jointer you have.Its clear you want it to be accurate. The machines that I have had to adjust were old good quality machines made of Mechanite with factory hand scraped tables,so it was only adjustment was needed. Wouldn't that be easier?

[Myk Rian]

In order to flatten the tables with any surfacing machine, the tables need to be mounted to the frame of the jointer. That's how they're done in the factory.
It would take quite a large machine to do a 12" jointer.
.010" isn't worth it to me.

[joe milana]

Supposin' the .010 is a dip across the width of the outfeed table all the way down it's length. Now that would suck!

[ian maybury]

Hi Mel. My machine is a Hammer A3 410. It's actually within factory spec, and it's possible that i've missed something - hence my not saying too much about the model of machine.

So far as i can tell with an engineer's straight edge and feeler gauges it seems to have a hump across the width of the outfeed table of about 0.008in high about 2/3 of the way along, and a dip in the edge of the infeed table closest to the knives of about the same that goes back for about 8in. The tables are actually dead solid, it looks though like when they were machined (milled) that some combination of perhaps a slightly too rapid feed rate (high cutting forces) and inadequate support led to some issues in this specific case.

These machines in general enjoy a very good reputation - it doesn't seem typical. Going back to the factory isn't really an option as (a) it's within spec, and (b) i've had it for about two years - unused due to unexpected circumstances.

So far as i can tell it's the table inaccuracies that are conspiring to make it want to joint slightly convex. It's actually not hard to get it properly aligned in that the adjustments are straightforward - the knife height adjustment using the Felder quick change system is especially simple and effective.

It's cutting very cleanly now, but having worked incrementally through knife height settings from too low (catching the lip of the outfeed table) to too high (snipe setting in) without success re. the tendency to joint convex the only way i can get it to joint almost straight is by dropping the infeed table by maybe 0.010in. Not really happy with that though - it looks like it's compensating for the bump in the outfeed table deflecting pieces upwards. There's a gap of about 1/32 at the ends when two 40in pieces are placed jointed edges together.

Hopefully hand scraping the tables flat will sort it out, and be a fun exercise too. I've all the kit in house now, and even had a quick try out with the scraper (a 25mm Sandvik carbide insert model). Very promising, it cuts really well and seems very controllable. I thought of trying a hand held belt sander Joe, but wasn't sure i could trust my touch with it.....

ian

[Phil Thien]

If you guys are going to hand-scrape your tables, please take some pictures and write it up. I would like to see the process and the results.

[ian maybury]

Can do Phil. it'll probably take a week or two...

ian

[Myk Rian]

If you guys are going to hand-scrape your tables, please take some pictures and write it up. I would like to see the process and the results.
Search Youtube for it. Not an easy task by any means.
http://www.youtube.com/watch?v=ZTru-KEdaR8 as an example.

[Jamie Buxton]

..Scraping as a flattening method uses marking blue on a surface plate to identify the high spots to scrape off - you rub the table on the plate and the blue transfers to the contact points. Numerous rub and scrape cycles later your tables are flat....

When you say "scrape", what are you using as a tool? "Scraper" on this forum usually means a cabinet scraper, which I don't think would cut the steel table.

[Chris Fournier]

I would strongly suggest that folks take a very close look at what is involved in "scraping" a machine tool. Perhaps they should try to hunt down a copy of Machine Tool Recondtioning by Connolly? By the time the first chapter is read it should be apparent that just "having at it..." is a pretty foolish plan. In fact if would take months to just build the tools required to undertake the task presented in this thread. To say that there is some serious bravado in this thread is an understatement. A starter project would be scraping a surface flat - your straight edges required to transfer "flat to your jointer table. Unfortunately flat must be referenced to another object - the cutter head. Things get more complicated and quickly. Machinists would consider scraping a machine tool to be a specialty skill with in their trade. To suggest that your average woodworker can scrape in a machine tool to better thatn manufactured tolerances is pretty naive/bold/stupid. The outcome is most likely a messed up machine. The cost of putting together a scraper's tool kit is well beyond most of the posters budgets on this forum I can assure you - in most cases the cost would be greater than the machine under consideration.

It's not helpful to throw out absurd "solutions" like this.

[Jerry Wright]

This thread is illustrating the point that some folks build shops and rebuild machines and others build projects in whatever shop and with whatever machines they have. I doubt that the period furniture at Winterthur in Wilmington, ever saw a .010" tolerance anytime over the past 200 years!
"BTW, my machine is flatter than your machine.":)

[ian maybury]

My guess is that the tolerances in period furniture are tight Jerry. There's places where absolute dimensions don't necessarily matter as long as everything is the same, but a a well fitted drawer for example is surely to size to within a few thou. Ditto the opening. The difference is presumably (guessing) that they didn't have machines that cut straight in a single pass, they instead sneaked up to straight edges and precise fits using hand tools.

It seems well worth putting in a couple of days labour to optimise the performance of a $6,000 machine. (blueprint it you might say)

There's links to a variety of metal scraping demo videos, instruction manuals and tool and equipment supplies in post 5 near the start of the thread Jamie - liberally sprinkled (as are subsequent posts) with warnings and the caveat that scraping is a skilled task and that there's lots of scope to mess up. It's most definitely not a thread promoting the idea that all and sundry should rush off and scrape their own machine tables - the possibility was only mentioned in passing, and additional information tabled in response to questions.

It's certainly not a job to be undertaken lightly Chris, but it's by no means as expensive to set up for as it used to be and isn't remotely close to the cost of the machine. The granite surface plate required for use as a reference can these days be bought very cheaply if you do your homework e.g. http://www.grizzly.com/products/18-x-24-x-3-Granite-Surface-Plate-No-Ledge/G9654 and a ready to use carbide hand scraper costs less than $100 too. e.g. http://www.machinerepair.com/Orders.html

Now i'm the first to admit that the task may contain hidden pitfalls, but given a high level of hand tool skills and that the options to have the tables ground locally were limited (concerns about accuracy of fixturing and high costs) it's a lot more attractive to me to place the job under my own control - and be left with a scraper and surface table too, both of which are potentially useful for all sorts of shop jobs....

ian

[Jerry Wright]

One of the neat thing about this site is the great Exchange of ideas and opinions. I am only pointing out that seasonal wood movement of well dried wood is well understood. The annual movement of woods in reasonably regulated environments is many times the .010"/foot that we are discussing. Suffice it to say that a drawer fitted to a few thou will enjoy seasonal self locking episodes.

[joe milana]

That's the spirit Ian http://www.johnbridge.com/vbulletin/images/smilies/thumbsup2.gif Besides, we are not talking about grinding a lens for the hubble telescope. There are amazing things done in garages and basements by the participants of this forum. Flattening a piece of cast iron is hardly beyond the scope...

[Phil Thien]

I've been watching some videos at youtube.

What do you plan to do AFTER the scraping? Do you just leave the surface? Or do you do something to finish the surface (like sand it or something)?

I know aluminum is much softer than CI, but when my jointer fence was causing problems due to a substantial twist, I cut some belts from a sander and I glued them down to an MDF board which I clamped to my bench. I then ran the fence back and forth over the sandpaper until the twist was gone. It took a little bit of concentration (to apply pressure correctly). But it went very fast and I had a nice, flat fence. And it was smooth.

The scraped surfaces sure don't look very smooth.

[Chris Fournier]

I've been watching some videos at youtube.

What do you plan to do AFTER the scraping? Do you just leave the surface? Or do you do something to finish the surface (like sand it or something)?

I know aluminum is much softer than CI, but when my jointer fence was causing problems due to a substantial twist, I cut some belts from a sander and I glued them down to an MDF board which I clamped to my bench. I then ran the fence back and forth over the sandpaper until the twist was gone. It took a little bit of concentration (to apply pressure correctly). But it went very fast and I had a nice, flat fence. And it was smooth.

The scraped surfaces sure don't look very smooth.

A properly scraped surface is in fact very smooth. Light relecting off of the scraped surface is deceiving on a final pass the surface deviations are much less than 0.001" more in the order of 0.0001". A scraped surface also hold oil quite nicely which is a benefit in the metal working machine world where the oil lubricates bearing surfaces.

[Mel Fulks]

Good analogy ,Joe .When they first made the Hubble they ground by the wrong formula ....but they fixed it!

[Phil Thien]

A properly scraped surface is in fact very smooth. Light relecting off of the scraped surface is deceiving on a final pass the surface deviations are much less than 0.001" more in the order of 0.0001". A scraped surface also hold oil quite nicely which is a benefit in the metal working machine world where the oil lubricates bearing surfaces.

Thanks Chris.

So instead of hand-scraping, has anyone considered using a router sled and rails like are sometimes used for flattening wide boards, or workbenches? I would imagine a carbide-tipped bit adjusted to just kiss any peaks may provide a more predictable outcome.

Of course, I'd first determine whether the not-perfectly-flat surface is causing a problem. Irregularities have to be averaged over the width of the work piece. And the further the irregularities are from the head, the less pronounced their effect. Calculus anyone?

Bottom line, if my boards came out flat and twist-free, I'd leave it alone.

[ian maybury]

Hi Phil. Having an Agazzani bandsaw with a table purposely machined to have quite deep grooves in it (possibly with a round nosed tool on a now little used machine tool over here is called a shaper - nothing like a woodworking shaper) that works just fine and is commonly spoken of as being desirable (mutterings about less suction and the like) i concluded that if i could just produce a network of reasonably closely spaced high points in the same plane that it would be fine. In practice though as Chris says most of what's seen in a scraped surface is optical/reflection.

The big no no is probably what you might call a 'toothy' or grippy sort of surface that holds wood. Hopefully it won't be required, but if it arises it should be very capable of sorting out by all sorts of means. Best to see what arises first...

Scraping to a very smooth surface seems to be a technique deal too - in that while it's possible to remove a fair amount of material by being aggressive with the scraper it seems like the final passes need a lighter touch. (you can see distinctly different cutting strokes in action in those Japanese videos)

I thought of the possibility of stuff like a router, or a series of very light runs through a wide belt sanding machine, or even careful use of a hand held belt sander - but chickened out. There may be potential there, although a router would need incredibly solid support to maintain a flat plane to within the couple of thou that is the target here. The big attraction of scraping is that it's a gradual process guided all the way by the surface plate - with what seems like less potential for a major screw up. Much like the Hubble Mel if one pass is wrong it can be 'fixed'.

The other biggie that's put scraping in the frame as a DIY accessible option is that it requires a decent surface plate - an items which cost $000s not very long ago but is very low cost these days.

Just to put this scraping business in perspective. It is a skilled task, and having the correct equipment is advisable - but it clearly doesn't require a miracle worker to pull it off. It has developed a lot of mystique, but my guess is that's as much to do with the pursed lips and the long indraw of breath before tripling the price as anything. :) (unscrupulous machine resellers are nowadays re scraping worn out machine slides so they look unworn to the eye impressed by this mystique)

One of the first jobs that 17 year old toolmaking apprentices were often handed for example was to scrape in the then typically quite large cast iron surface plates used in the toolroom/metrology room - they picked up wear and damage over time. http://tiny.cc/89ogpw Basically because it was a PIA job. Ready made carbide insert scrapers have made it a lot easier these days - back in the day they used a ground file end which i'm told blunted in no time.

ian

PS I've just done the aluminium fence from the same machine in the manner you describe Phil (it was yourself or somebody else that inspired it by a short comment some time ago - mine was cupped by about 0.005in), and it's going back for re-anodising this morning. Relatively straight forward, and a very nice finish - although it could progress into quite a hard job (as in lots of work) if there's a lot of material to remove. I stuck down sheets of abrasive (80 grit - finished it with a 3M synthetic steel wool pad) on the slider of my saw which is dead flat using a Pritt Stick (that's a dry easily removable stationery adhesive that comes in the form of a wax like stick) It's NOT waterproof (is designed to be water soluble), but the benefit is that you can easily wash the residue off with warm water. A length of 2x4 with blocks on each end to sit lengthwise on and drop over the ends of the fence and a handle on top to help pushing and pulling eased the sanding - the sand paper gets quite a grip when cutting over that sort of area and it's easy to skin a knuckle too. (as i found)

It's probably not strictly necessary, but is straight forward - so I got the anodising on the fence stripped by the anodiser before sanding. (stripping leaves a satin aluminium finish that could easily be mistaken for anodising - but is soft aluminium)

It's worth noting that about half of the cupping in my fence was caused by a less than perfectly flat folded mild steel mounting bracket - easily sorted with a few passes on a similar set up to that used for the fence - only in this case on the new surface plate. About half of the cup in the fence came out when it was unbolted from the bracket, although it didn't show up until checking it after the stripping.

[Erik Loza]

No dog in this fight but if it were me and if the jointer table did not present any issues in terms of getting a flat/square board, I would not worry about it. Reason being that "yes", you could pull a table and machine it to whatever thousandth you want but the moment you re-mount it and lock the latches, you induce stress back into and it might distort again. In the world of automotive engine machining, there is a process call "torque plate" honing, whereby a steel plate with the exact same number of bolts is torqued to spec, to the cylinder deck, before the honing mill hones the cylinders. The torque plate duplicates the exact same uneven and asymmetrical stress pattern the the cylinder head does, when it is torqued down, so you get a perfectly true bore on each cylinder. You would need a similar setup in order to do the infeed/outfeed tables on any combined machine. IMHO, that is a one-way rabbit hole to go down.

If it was fence, then "yes", something would need to be done about that.

Just my 2-cents as always,

Erik Loza
Minimax USA

[Steve Rozmiarek]

If it bothers you, why not just sell it to someone who it does not bother?

[Derek Arita]

If it bothers you, why not just sell it to someone who it does not bother?
I thought about that, but decided not to. I recently had to downsize my shop, so having a jointer and a planer in one, is a great advantage. Secondly, when I purchased the machine, I was still working a full time job and had the extra cash. I could never afford this machine now, as I am retired.
Clearly, there are woodworkers who work with the machines they get and produce great stuff. There are also those who regard the machines as part of process and are just as picky about them as they are the finished piece. I get just as much enjoyment out of owning the machines and maintaining the machines, as I do the working of wood itself. I enjoy working toward perfection in both, but realize I will never achieve it in either.
I wish I could be a Neanderthal and use only hand tools to work wood, but then, even those guys strive to maintain perfect hand tools. Truth is, I just don't have the patience and skill that it takes, nor the inclination towards that much physical labor. My Grandfather was a woodworker from Japan and, I'm told, spent hours working on a single joint. He was a builder and furniture maker in Hawaii. Unfortunately, he was gone by the time I came along, but boy do I wish I could have spent time with him in the shop...the things he could have taught me...

[ian maybury]

Hi guys. Another scraping video, it's quite instructive: http://www.youtube.com/watch?v=nOJrhrne80s No mystique, he just gets on with it. It shows stoning off to remove the burrs left by scraping...

ian

[Derek Arita]

Scraping a 12" jointer looks like a huge job, especially if you don't already own the equipment for it. The power scraper looks a little easier. Also, my jointer surface is the type that has the large ridges throughout, so I'm not sure how you could scrape along the "ridges" only and not the "valleys". With that in mind, I can imagine sanding the surface by hand, before scraping it. I'll enjoy seeing the results of your scraping efforts. Please show the equipment you used as well.

[Andrew Joiner]

Derek,
I flattened a 24''x 24'' bandsaw table with a belt sander.

You could practice on a piece of scrap metal first if you want. A light touch on the switch and a firm down pushing grip are needed. Of course mark and check all for your highest spots often as you work.

It goes pretty slow so it's almost easier than getting wood perfectly flat. That is, it's harder to mess it up and get gouges/divots in cast iron like wood.

[brian c miller]

Find a place with a large blanchard grinder... IMHO for a large subplate this is the way to do it... a surface grnder would take WAY too long.


See if you can find someplace like http://www.precisiongrinding.com/

We used these guys to true up machine subtables for CNC mills... for what they do it's pretty reasonable.

BCM