# Machinist opinion re: General cast iron table not flat?



## corth (Jun 13, 2014)

I am a big fan of lock miters, but I find it requires considerable precision. My old MDF router table top with its slight bow just wasn't cutting it, so recently I decided to upgrade my router table to a General/Excalibur cast iron top thinking that a cast iron router table top would necessarily be flatter and more accurate than a MDF table top. That was a dumb assumption on my part.

My new General/Excalibur cast iron top arrived not too long ago and I set it up. I quickly realized that I cannot get the lift/insert perfectly flush with the cast iron table top. The aluminum insert itself seems flat (within 0.003" or better). However, the cast iron is out of flat such that one of the corners has to be up 0.008" high to get the other 3 edges flush. As a result, there is a bit of a "clicker" when a board runs over the insert. I know that 0.008" is probably within the manufacturer's spec, but I would really like to be able to get the insert flush. The cast iron top is rigid enough that I don't think any shimming will fix this. Now I am learning about Blanchard milling and wondering if it is reasonable to get this 32" wide top milled to within 0.0015" of flat.

Are there any machinists out there who can comment? What is the tolerance of Blanchard milling over 32"? Is there a better way to get my cast iron top flat?


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## Semipro (Mar 22, 2013)

?, welcome to Router Forums, glad to have you join us, I'm positive the members of the community would be more than willing to answer any questions you have 
I am sure someone will able to help you ( but a machinist I'm not) again welcome


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## RainMan 2.0 (May 6, 2014)

Welcome to the forum . I'm sorry I can't be of any help but I'm sure there's someone that can give you some input .
I find this post interesting as I had ordered there cast router table also and then cancelled the order after I assembled my GI table saw and found it's casting was far less than perfect.
And I didn't order there cheap saw either but the GI270

I think this is the outcome of getting there parts made in Taiwan as opposed to the good old days when they were made locally


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## Stick486 (Jan 4, 2013)

corth said:


> Now I am learning about Blanchard milling and wondering if it is reasonable to get this 32" wide top milled to within 0.0015" of flat.
> 
> Are there any machinists out there who can comment? What is the tolerance of Blanchard milling over 32"? Is there a better way to get my cast iron top flat?


it's Blanchard grinding not milling......

Blanchard Grinding, technically referred to as Rotary Surface Grinding, quickly removes stock from one side of a part…typically a part too large to be Double-Disc Ground is Blanchard ground. Dimensional tolerances to ± .001", parallelism to .001", and flatness to .0005" are achievable.
Using significantly greater horsepower than other grinding methods, Blanchard Grinding removes large amounts of stock quickly and efficiently.

Blanchard Grinding is ideal for large parts, your table top is medium to medium small. 
Blanchard Grinding surface finishes go to 150 Ra and higher. 16 Ra is achievable if you want to spend. 8 is mirror

Surface Finish Charts : L.J. Star Incorporated


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## Stick486 (Jan 4, 2013)

corth said:


> Is there a better way to get my cast iron top flat?


Blanchard should be all you need...
but if you have large pockets or many wallets and if you could find somebody with the machines to do them......

There's:-(but what for?)

DOUBLE DISC 

Flatness: Within .0003
Parallel: .0003
Finish: 16 RMS

HYPROLAPPING 

Tolerances: to .0002
Flatness: Within .00005
Parallel: .0001
Finish: 2 RMS

Note: Parallel is top relative to bottom...


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## phillip.c (Aug 9, 2012)

First you might consider giving the company a call and informing them that their product is flawed and you request a replacement.


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## old55 (Aug 11, 2013)

Welcome to the forum.


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## Stick486 (Jan 4, 2013)

phillipdanbury said:


> First you might consider giving the company a call and informing them that their product is flawed and you request a replacement.


probably get more of the same...


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## corth (Jun 13, 2014)

Stick486 said:


> probably get more of the same...


I suspect you are right. If I can find someone to grind this router table flat for less than $150, then I will do so and mark it up as a learning experience. I'll never buy a General International tool again. My General table saw and drill press that were made in Canada on the other hand are beauties.


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## RainMan 2.0 (May 6, 2014)

corth said:


> I suspect you are right. If I can find someone to grind this router table flat for less than $150, then I will do so and mark it up as a learning experience. I'll never buy a General International tool again. My General table saw and drill press that were made in Canada on the other hand are beauties.


And it's such a shame as I really thought they were quality products . Since they went international they've gone down hill IMO .
I would be tempted to try a replacement once , although I agree with a Stick as it will probably be more of the same . I was sure disappointed when I had between a 1/8" -1/16" gap on my TS . Luckily I managed to straighten it by tightening the outside bolt first , then lining the wing up with the centre and tightening it , then I put a clamp on the outside of the wing forcing the centre up and tightened it's bolt which managed to correct it . 
But I shouldn't have to do that with a $3,000 saw 

As I was saying after your incident I'm glad I put the kibosh on there cast router table . I'm going to build a torsion box under an Incra table and be done with it


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## Jerry Bowen (Jun 25, 2011)

O.k., you guys that know about machining are talking way over my head, but the thread begs a question. I just recently started cutting miter lock joints. I have a router tablel that I bought from Incra Tools serveral years ago, never checked it for being flat. The plate is the plate that is part of the JessEm Mast R lift but sold by Incra.

The results that I am getting with the lock miter bit are, in my opinon, very good, but perhaps my standards are nearly as high as yours are. As long as the edges of the two pieces are sharp and the width of the workpieces are not dimenishe by the cuts and when the parts are glued up the seam at the corner is nearly invisible at close range, no gaps in the joint looking at the ends of the two jointed parts, what else should one be looking for? 

I double seriously if my router table and plate are any where near as flat as you guys are talking about. When I started posting on this forum and was talking about close toleances, I was quickly told that such accuracy was not important when working with wood and so I eventually got weaned away from thinking such terms. But now, here is a thread that is certainly bring up the subject of thinking in thousandths of an inch. What am I missing if you don't mind enlighting me?


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## MikeMa (Jul 27, 2006)

The critical juncture for a router table is the plate, that needs to be flat. The rest of the table needs to be flat enough to not interfere with the stock move flat along the plate and through the bit. The rest of the table doesn't necessarily need a high degree of precision as its function is to support the plate and work piece.

In regards to what the original poster is saying, I would consider that a flawed table since it is getting in the way of the proper operation of the table. I would be on the phone with the company seeing about getting a replacement or refund.


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## phillip.c (Aug 9, 2012)

Perhaps see if they will replace it for free. If the second table is also out of flat, you can then see about grinding.


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## corth (Jun 13, 2014)

Thank you to everyone who responded to my initial post. It seems my part of the country is devoid of precision grinding facilities. The only shop nearby that might even have Blanchard grinder large enough to grind this top is a defense/aerospace contractor, and they're not interested in small potatoes. 

I've emailed General to see if they will do anything to help. I'll let you know....


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## DaninVan (Jan 1, 2012)

Are there any engine re-builders in your area, Corth? Not my area but I'd assume they have some way of machining engine heads?


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## RainMan 2.0 (May 6, 2014)

corth said:


> Thank you to everyone who responded to my initial post. It seems my part of the country is devoid of precision grinding facilities. The only shop nearby that might even have Blanchard grinder large enough to grind this top is a defense/aerospace contractor, and they're not interested in small potatoes.
> 
> I've emailed General to see if they will do anything to help. I'll let you know....


Very interested to see there response . I suspect there going to exchange it and hopefully the next ones exceptable


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## Stick486 (Jan 4, 2013)

RainMan1 said:


> Very interested to see there response . I suspect there going to exchange it and hopefully the next ones acceptable


suspect chinese manufacturing..
good luck w/ that...

I'd be looking for an American or Canadian manufactured top..
JessEm makes a very nice top and w/ the right under supports... no issues...


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## RainMan 2.0 (May 6, 2014)

Stick486 said:


> suspect chinese manufacturing..
> good luck w/ that...
> 
> I'd be looking for an American or Canadian manufactured top..
> JessEm makes a very nice top and w/ the right under supports... no issues...


I believe GI international is made in Taiwan. Same poor build quality and castings I suspect .
I know guys used to swear buy GI that was manufactured in Canada. So much for manufacturing overseas :bad:


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## corth (Jun 13, 2014)

RainMan1 said:


> I believe GI international is made in Taiwan. Same poor build quality and castings I suspect .
> I know guys used to swear buy GI that was manufactured in Canada. So much for manufacturing overseas :bad:


I am still waiting to hear back from General about the cast iron top. Believe me if there was a cast iron router table top made in North America, I would have bought it instead. Even Onsrud's inverted routers don't have cast iron tops. I briefly consider Festool's version of a router table, but it seems more portable than beefy. I definitely wanted beefy.

Oddly enough many parts on the General/Excalibur router table can be found in other vendors router tables. The fence on the General/Excalibur is identical to Jessem's router fence. General's lift has some similarity to Jessem's lift, such that Jessem's Tab-Loc inserts fit the General plate perfectly. In Europe, the General's router lift is essentially the same as UJK's Router Elevator. The base for this router table is ubiquitous and available from many different vendors.


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## corth (Jun 13, 2014)

A quick update: I am the original poster. General's response to my problem has been overwhelmingly positive. Excalibur's product manager happened to be driving through my area and stopped by my house to help me with the router table. He acknowledge that there is an issue with this cast iron router table top and has resolved to get it fixed. I will post an update when all is done, but I am confident that I am in good hands. Kudos to General and Excalibur for what can only be described as superb customer service.


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## corth (Jun 13, 2014)

I am the original poster for this thread. General/Excalibur's response to my concerns have made me realize they are serious about customer service. I am confident we will get this resolved.


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## corth (Jun 13, 2014)

RainMan1 said:


> I believe GI international is made in Taiwan. Same poor build quality and castings I suspect .
> I know guys used to swear buy GI that was manufactured in Canada. So much for manufacturing overseas :bad:


General/Excalibur's response to my concerns have made me understand that they are serious about customer satisfaction. I am confident this problem will be resolved in the near future. Moreover, I am impressed with General's/Excalibur's operation. I will buy from them again.


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## corth (Jun 13, 2014)

General has responded in an overwhelmingly positive fashion to my concern about getting the router plate flush. From what I have seen, they are committed to customer service. I believe this issue was a "fluke", and it will be resolved. I'll post more when all is resolved.


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## RainMan 2.0 (May 6, 2014)

corth said:


> General has responded in an overwhelmingly positive fashion to my concern about getting the router plate flush. From what I have seen, they are committed to customer service. I believe this issue was a "fluke", and it will be resolved. I'll post more when all is resolved.


Good news . I suspect my table saw being warped was a fluke to . I never pursued it so I have no idea what the outcome would have been . I really didn't want to pack 600 pounds back to the store . 

Looking forward to hearing about the next router top . I'm going to be a tad concerned if the next ones warped though


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## RainMan 2.0 (May 6, 2014)

corth said:


> A quick update: I am the original poster. General's response to my problem has been overwhelmingly positive. Excalibur's product manager happened to be driving through my area and stopped by my house to help me with the router table. He acknowledge that there is an issue with this cast iron router table top and has resolved to get it fixed. I will post an update when all is done, but I am confident that I am in good hands. Kudos to General and Excalibur for what can only be described as superb customer service.


Stopped by your house , now that's service ! Wow


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## corth (Jun 13, 2014)

RainMan1 said:


> Stopped by your house , now that's service ! Wow


This is especially true, considering my house is literally more than 1000 miles away from General.


P.S. Sorry for the multiple posts earlier. I typed a few replies and the system seemed to bounce them back. I thought my browser wasn't working, but it looks like the posts were awaiting moderator's approval.


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## timbertailor (Oct 4, 2009)

Thanks for the update. It is reassuring to hear that they appear to be responsive.

Keep us posted.


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## RainMan 2.0 (May 6, 2014)

corth said:


> P.S. Sorry for the multiple posts earlier. I typed a few replies and the system seemed to bounce them back. I thought my browser wasn't working, but it looks like the posts were awaiting moderator's approval.


Ok, I was wondering what was going on . I thought maybe the guy from General was holding a gun to your head or something


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## Stick486 (Jan 4, 2013)

corth said:


> general has responded in an overwhelmingly positive fashion to my concern about getting the router plate flush. From what i have seen, they are committed to customer service. I believe this issue was a "fluke", and it will be resolved. I'll post more when all is resolved.


wow!!!


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## biocmp (Jul 2, 2014)

Corth,

Any updates? Have you discussed the tolerance you are looking for? Are they replacing? Did they make mention of any manufacturing processes that have caused problems? I really want to find a cast iron or full-aluminum top that is dead flat but in 2014, it appears that may be too much to ask. 

From what I've seen: phenolic tops sag over time, MDF doubly so and cast iron tops aren't precision machined any better than .008

Keep us updated as I have some difficult decisions to make soon (because I badly need a router table).


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## corth (Jun 13, 2014)

As of last night, I am in possession of a new top. I'll update after I have the chance to inspect it for flatness. There may be some other issue(s) that we don't fully understand yet though, and it could be as simple as the procedure with with the router is installed in the lift. Excalibur/General has been with me every step of the way so far. Kudos to them.


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## RainMan 2.0 (May 6, 2014)

corth said:


> As of last night, I am in possession of a new top. I'll update after I have the chance to inspect it for flatness. There may be some other issue(s) that we don't fully understand yet though, and it could be as simple as the procedure with with the router is installed in the lift. Excalibur/General has been with me every step of the way so far. Kudos to them.


Good to hear . With any luck this ones the winner


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## MAFoElffen (Jun 8, 2012)

Sounds like this is getting resolved... But some additional sidenotes to this (in case someone else has a problem like this and needs ideas).

If the plate is lower than the table, if you drill and tap holes through, near the corners, then you could use set screws to level the plate (OP siad he was getting plate woble as the stock traveled over the plate.

If the plate still has travel, I use toggle clamps under the table to lock the riser securely down to the table. This is overkill for most people and most applications... but if your are routing a profile where you need things stable, secure and looking for accuracy, this works good.

On another table that I mainly use for cabinet profiles, after I level the plate, I have other holes in the corners, that take tapered headed screws and lock that plate down with screws.

(Of course, I make my own plates out of aluminum. Not sure how poly plates would work doing that.)

Like I said, not your normal mounting... more suited for HD commercial work.


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## RainMan 2.0 (May 6, 2014)

Ok the suspense is killing me!


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## timbertailor (Oct 4, 2009)

RainMan1 said:


> Ok the suspense is killing me!


Me too!


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## RainMan 2.0 (May 6, 2014)

lol that's awesome Brad ^^



If Corth isn't away on holidays , I'm getting a little concerned here :sad:


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## corth (Jun 13, 2014)

At last an update!

The Excalibur manager swapped out my cast iron table at no cost to me, and we reinstalled my Porter Cable router in the Excalibur lift. However, we once again could not get the lift plate flush with the cast iron table top. We were perplexed by the situation to say the least. The manager took my lift back to General to analyze what was going on. 

It turns out that our inability to get the lift plate flush with the cast iron top was due to two problems. What we didn't understand initially is that the thick aluminum lift plate was being distorted out-of-flat by 0.006" by the hardware mounting the router motor to the lift. I observed a 0.011" step up from the cast iron top to the lift plate at one corner. I thought this step up was solely due to an out-of-flat cast iron top, but I was wrong. The cast iron top was not flat, but likely was within an acceptable tolerance--my cast iron top probably did not need to be replaced! My step up was due to the additive effect of a slightly out-of-flat cast iron top and a slightly out-of-flat aluminum lift plate. Each deviation is probably within the limits of acceptability, but when the two deviations are added together, the end result is not acceptable. My case was unique in that these deviations were additive, and I am not the type of person to overlook them. For other owners of this tool, the deviations may have been subtractive essentially canceling out each other. Excalibur has determined the root of the lift plate deviation which I will not detail since it is quite technical. Nevertheless Excalibur, has changed the router lift assembly at the factory to minimize the likelihood of other users encountering this problem. They are also re-writing the instruction manual recommending a more accurate technique for installing the router motor in the lift. If anyone else has similar issues, Excalibur should be able to help without a significant downtime for the end user.

Excalibur was with me every step of the way, and their commitment to getting this problem solved has been simply spectacular.


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## DaninVan (Jan 1, 2012)

Thanks for the update 'Corth'!
Great customer service needs to be acknowledged. Bouquets to Excalibur,eh?...


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## timbertailor (Oct 4, 2009)

I do not consider a cast iron top to be within spec if it is 0.005" out.

I use my table saw top as a reference and to make other "flat" work surfaces.

I can not get a 0.0015" feeler gauge under a straight edge anywhere on my table and its just a cheap contractors saw.


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## timbertailor (Oct 4, 2009)

DaninVan said:


> Thanks for the update 'Corth'!
> Great customer service needs to be acknowledged. Bouquets to Excalibur,eh?...


How about a Minion Cheer instead?


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## RainMan 2.0 (May 6, 2014)

I was getting worried ther for a while , and I'm glad to hear the company stood by there product


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## al m (Dec 13, 2012)

Sounds like what I would call a case of accumulative error,everything is within tolerance,but in such a way that when all the tolerances are "stacked " in assembly, become un acceptable
If it were mine,and I had the machinery available ,I would assemble the pieces in a happy median,meaning some adjustment was still avaliable and surface grind the entire assembly flat.
This will only work if all surfaces are ferris,and am scrambling to ember if you said the insert was aluminum


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## grumpygeologist (Dec 11, 2014)

*my cast iron table is flat.*

I have the cast iron general/Excalibur router table top and router lift. With the lift properly leveled out and testing with a machinist's bar, the table and lift are perfectly flat - or rather let's say that I couldn't fit my thinnest shim anywhere between the bar and the table or lift.

The cast iron top has more levelling screws than I've ever seen in another top.

Enjoy 

Glenn

ps. does anyone know what insert rings will fit the general lift? Have tried a set of jessem rings but they don't work. The general ones seem rather hard to find


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## paduke (Mar 28, 2010)

corth said:


> A quick update: I am the original poster. General's response to my problem has been overwhelmingly positive. Excalibur's product manager happened to be driving through my area and stopped by my house to help me with the router table. He acknowledge that there is an issue with this cast iron router table top and has resolved to get it fixed. I will post an update when all is done, but I am confident that I am in good hands. Kudos to General and Excalibur for what can only be described as superb customer service.


There are manufacturer reps that check our forum. Mike used to liaison with them for our members. Glad to hear how the experience led to improvement or all


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