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krprice84
09-25-2015, 11:48 AM
Ok, first off, my name is Kevin, and I'm a single father who lives in Alberta, Canada. Didn't see an "intro's" section, so I figured I'd throw this in here first. I'm into doing my own gunsmithing, do all my own work on my truck and motorbike, etc. I've wanted to get into milling and machining for a long time, as using a file and vise to do some work is just too imprecise.

I've actually used (please don't flame!) a 12" Delta drill press to do some really light machining on my CZ858 (to allow it to take AR/STANAG pattern magazines, which come in a "pistol" version that allows us Canadians to use 10 rounds in our semi-auto rifles legally). It worked quite well, though I was scared to hell the chuck was going to drop out and attack me. I went in very small passes (I'd estimate about 10 to 20 thou per pass, at the most), and did about 15 passes, and the finish was actually decent, though there was a pretty significant burr on the edge of the cut. But it worked. This jump started me into really wanting to find a basic mill.

Problem is, I don't have a shop. I've got a basement that I've turned into my shop. So there's no room for a nice Bridgeport or similar machine. I was stuck looking for a benchtop milling machine, so it was looking pretty bad. Definitely no room for a lathe (at least not a standalone lathe, maybe down the road a milling machine/lathe combo, if they're any good at all).

I finally came across a used vertical milling/drilling machine on Kijiji, and jumped at it. It's a Force International vertical milling/drilling machine. Very small, probably not good at all for doing any real serious work, and I highly doubt it's much more rigid than a moist spaghetti noodle. But it's mine, and it's what I have to work with.

Anyways, that's me. What I posted here for was to ask a few questions, and I hope they're ok to ask here (the other machining forum bans anyone who discusses such "awful" machines as these).

1. Does anyone have a resource (other than random Youtube videos - youtube videos are fine if you respect what the guy says and he knows his stuff, but most of the ones I've found are fairly specific to big machines, or they're using CNC machines) that I can utilize to help me learn the basics about milling and machining? I know REALLY basic stuff, but when the talk turns to "what DOC are you using, what type of coolant/coolant system, indexable mills, feed speed, etc" that stuff goes right over my head. I don't even understand how feed speed can be determined on a manual milling machine - feed speed, for me, is about "not very many inches per minute". So I'm looking for a resource that can help me learn how to best utilize my wet-noodle-machine.

2. Does anyone have any suggestions on how much I could realistically expect to do with this type of machine (I don't even have a model number, but it's basically the same machine as the Sieg X2 - in fact, I think it IS the same machine, just painted a different color. Every knob, bolt, cover, etc, is all in the same place, and looks to be the same). What my goal is, is to be able to machine small parts for my guns and bikes, and maybe work on making a knife or two, and other such smaller projects like that. I understand this machine is going to have serious limits.

3. Is it reasonable for me to expect to be able to mill larger material, so long as I take smaller cuts? Or is it totally out of the ballpark? If so, why would it be out of the realm of possibility? In my mind, if I'm willing to take off small bits of material with each pass, and do lots of passes, then I see no reason why I couldn't mill a 2" deep by 2" wide by 2" long hole into 1018 steel. I understand I'm not going to be hogging out 1/2" at a time, and that's fine. The purpose of this is a hobby setup - so taking a long time isn't the end of the world. I can always leave it for the night and go back the next day to cut some more. I'm not running a production/for profit shop.

4. What is a reasonable amount of material (1018 or similar steel, aluminum (probably 6061 or maybe 7075), 4041 alloy steel, or some sort of stainless steel) that I could expect to cut per pass? Should I keep it to 10-20 thou, or can I go more like 100 thou deep? How wide should my passes be? Should I keep away from climb milling, or could this machine do it if I'm careful?

5. Should I stick to cold rolled 1018 or similar steels, or will hot rolled be ok?

6. Does anyone have any experience with case hardening (Cherry Red, Kasenit, etc)? Any tips on doing smaller pieces with it? I've heard of guys doing it in a molten bath of the stuff, but the instructions say to just dip the red hot piece into the powder/compound. Opinions/thoughts?

7. Does anyone have experience with hardening steels in a kiln? I'm looking at buying a smaller 120 volt kiln that I can setup and use to bring steel up to temperature, then lower it in a way that won't ruin it. I can definitely set it up outside or near the front door, so that I can oil or water quench the steel, but any resources or suggestions you guys might have would be awesome too.

Sorry for the bajillion questions, and I really hope I'm not putting this in the wrong place. If it is in the wrong place, please let me know and I'll make a new thread elsewhere before this one gets deleted.

Thanks, and I hope this forum is a good resource for a guy like me!

RichR
09-25-2015, 12:01 PM
Welcome to the forum. Another new member just bought a small machine and had lots of questions:
http://bbs.homeshopmachinist.net/threads/68030-Bench-top-Mill-typical-1st-post-questions
If you ignore the wet noodle posts you should find some useful information.

mars-red
09-25-2015, 12:38 PM
Ok, first off, my name is Kevin,

...

I finally came across a used vertical milling/drilling machine on Kijiji, and jumped at it. It's a Force International vertical milling/drilling machine. Very small, probably not good at all for doing any real serious work, and I highly doubt it's much more rigid than a moist spaghetti noodle. But it's mine, and it's what I have to work with.

...

Thanks, and I hope this forum is a good resource for a guy like me!

Wecome! I'm sure you will find a wealth of knowledge here. I have the littlemachineshop branded version of the same mill and like it real well, you just need to understand it and work within its limitations and capacities, like any other machine. I machine mostly steel, but occasionally brass or aluminum. I'll address some of your questions specifically:



1. Does anyone have a resource (other than random Youtube videos - youtube videos are fine if you respect what the guy says and he knows his stuff, but most of the ones I've found are fairly specific to big machines, or they're using CNC machines) that I can utilize to help me learn the basics about milling and machining?


There is a series of videos by "Open Source Machine Tools" on youtube, that I've always thought were good. Check out their first part on milling machines here:
https://www.youtube.com/watch?v=T5gjkYvMg8A



2. Does anyone have any suggestions on how much I could realistically expect to do with this type of machine (I don't even have a model number, but it's basically the same machine as the Sieg X2 - in fact, I think it IS the same machine, just painted a different color. Every knob, bolt, cover, etc, is all in the same place, and looks to be the same). What my goal is, is to be able to machine small parts for my guns and bikes, and maybe work on making a knife or two, and other such smaller projects like that. I understand this machine is going to have serious limits.

3. Is it reasonable for me to expect to be able to mill larger material, so long as I take smaller cuts? Or is it totally out of the ballpark? If so, why would it be out of the realm of possibility? In my mind, if I'm willing to take off small bits of material with each pass, and do lots of passes, then I see no reason why I couldn't mill a 2" deep by 2" wide by 2" long hole into 1018 steel. I understand I'm not going to be hogging out 1/2" at a time, and that's fine. The purpose of this is a hobby setup - so taking a long time isn't the end of the world. I can always leave it for the night and go back the next day to cut some more. I'm not running a production/for profit shop.



Your challenges, as the work gets larger, will be mostly around work-holding and running out of room between the bottom of the spindle and the top of the work. If not careful, you can end up with the work held in place, and then no way to change out the tool in the spindle without removing the work. When you get to stuff that size, that's really too big for the machine. Other than being aware of that, it's more a matter of how much material you are removing, rather than how large the work is. If you have the version of the machine with the tilting column, you will find that often complicates things if you wish to make angled cuts. I recommend angling the work, rather than fooling with tilting the column. I specifically bought the solid (non-tilting) column version, and I angle the work when necessary.



4. What is a reasonable amount of material (1018 or similar steel, aluminum (probably 6061 or maybe 7075), 4041 alloy steel, or some sort of stainless steel) that I could expect to cut per pass? Should I keep it to 10-20 thou, or can I go more like 100 thou deep? How wide should my passes be? Should I keep away from climb milling, or could this machine do it if I'm careful?


The width of your pass should be less than the half the diameter of the end mill. For depth, it depends on the width of your pass. I can comfortably take 0.25" depth of cut on mine, in steel, as long as the width of the pass doesn't exceed about 0.25". Much more than that in either dimension, and chatter becomes a problem. I can use the entire depth of the end mill's cutting flutes for finishing passes ("side milling") up to about 0.005". Your 1/2" depth of cut will work fine, as long as it's a pretty narrow width path, 0.015" maybe more if your machine is a better example of the breed. If you have the tilting column, then that is really going to reduce the rigidity and you may not be able to achieve the numbers I'm putting out here. Fly cutting is going to be an issue unless you have a very small fly cutter. Even mine, with the ballsy brushless DC motor, getting out to about a 2" radius on the cutter is getting touchy on steel. I usually keep it a tad under 2", with just a few thousandths depth of cut, and it does well. If yours has the older type of motor, I'm not sure what you can expect there. Pocketing/slitting, like you mention, is going to be especially slow going. Let's take your 2"x2" hole through steel, assuming it's not sheet metal. It might be best to start with the largest diameter center-cutting end mill that your machine can comfortably drive, and plunge it through the interior of your soon-to-be hole, repeatedly offset. The remainder can then be milled away from the edges. Pocketing real deep like that, to try to "core it out" is going to be awful, I'd avoid that if possible. Pocketing a slot is one thing, but a 2"x2" hole is another matter. If it was a large enough hole, you'd save time by drilling pilot holes inside the corners to fit your jewelers saw blade or hacksaw blade or bandsaw blade, and saw it out, then finish with the mill.



5. Should I stick to cold rolled 1018 or similar steels, or will hot rolled be ok?


Hot rolled is better for not warping as it is machined, but it has that tough scale on the outside. Just take a deep enough cut to get all the way under the scale for that first pass, and it'll be fine.



6. Does anyone have any experience with case hardening (Cherry Red, Kasenit, etc)? Any tips on doing smaller pieces with it? I've heard of guys doing it in a molten bath of the stuff, but the instructions say to just dip the red hot piece into the powder/compound. Opinions/thoughts?


That topic by itself can go on forever, I suggest searching through the forums for that specific subject and I'm sure you'll turn up lots of great info.



7. Does anyone have experience with hardening steels in a kiln? I'm looking at buying a smaller 120 volt kiln that I can setup and use to bring steel up to temperature, then lower it in a way that won't ruin it. I can definitely set it up outside or near the front door, so that I can oil or water quench the steel, but any resources or suggestions you guys might have would be awesome too.


This is another discussion that would take on a life of its own. I've found that this subject has a lot of severe mis-information online. It can be very difficult for a newcomer to tell fact from myth (or just plain lie) when it comes to heat treating carbon steel. This has also been discussed quite a bit here, but if you're interested in my own advice on the matter, coming from all my experience so far, then PM me and I'll gladly provide you with everything I know. Most older books on the subject of metal working cover heat treating, and they're usually spot-on. Old watchmakers texts, in particular, as the successful heat treatment of small steel parts is so crucial.

spongerich
09-25-2015, 12:48 PM
I'll take a shot at some of these. I'm no expert, but I've got a couple years in my shop on smaller machines.

Determining feed is pretty much seat of the pants for a machine without power feeds. (I suppose if you're anal-retentive enough, you could calculate the feed in handle turns per second and try to match that)
You'll just need to make a bunch of chips and get a feel for what works. Start slow but not too slow. You don't want the cutter to rub, you want it to cut.

You can definitely make large cuts by breaking them down into lots of smaller cuts. I have 2 small milling machines (not as small as yours) and I've found that plunge cutting is a good method for roughing out slots and pockets. You're putting more pressure along the stiffest axis of the machine that way... so plunge a bunch of times, then remove the material that's left by conventional milling.

Climb milling is possible but really only for a very light finish pass, IMO no more than 10 thou and 5 would be better.

Watch eBay for end mills. Since you've got a small machine and will be using small cutters, you should expect to break a good number of them. Good used ones are a lot more economical then buying new. I've had good luck lightly hand honing ones that are slightly dull. For the most part, stick with HSS. Carbide is great on larger machines but not so great on smaller ones. I'll occasionally use one on my Clausing 8520, but only for material that's especially tough or troublesome.

3 in one Lathe/Mill combos are generally not brilliant. Even the better ones are frustrating because the work envelope tends to be quite small. You'll find yourself wishing for a longer bed for lathe work and a taller column for mill work. Find a way to make room for a small-ish lathe. An Atlas 618 is a reasonably capable machine if you respect its limits. Build a bench with lots of drawers to minimize 'lost' space.... make a top that you can drop on for more bench space... If you can squeeze just a tiny bit more, a 9x36 South Bend or Atlas doesn't take up very much more room and would give you more capability.

Keep an eye on yard sales and estate sales for stock. Buying materials to practice on gets expensive. I'm always picking up scraps of aluminum and steel. Pieces that are too small to make something useful out of can be had for next to nothing.

Lastly, have fun and stay safe.

mars-red
09-25-2015, 01:27 PM
Climb milling is possible but really only for a very light finish pass, IMO no more than 10 thou and 5 would be better.


I forgot to mention this in my response, yes definitely very light cuts. I wouldn't climb mill even 0.010" on mine. 0.005" would the limit I'm comfortable with, personally, and that's plenty for a finishing pass on a machine this size.



Watch eBay for end mills. Since you've got a small machine and will be using small cutters, you should expect to break a good number of them. Good used ones are a lot more economical then buying new. I've had good luck lightly hand honing ones that are slightly dull. For the most part, stick with HSS. Carbide is great on larger machines but not so great on smaller ones. I'll occasionally use one on my Clausing 8520, but only for material that's especially tough or troublesome.


Speaking for mine specifically, the largest end mill I use is 3/4". 3/8" is probably as high as you'd want to go on one of these if you didn't have the latest motor with the infinitely variable speed control.



3 in one Lathe/Mill combos are generally not brilliant. Even the better ones are frustrating because the work envelope tends to be quite small. You'll find yourself wishing for a longer bed for lathe work and a taller column for mill work. Find a way to make room for a small-ish lathe. An Atlas 618 is a reasonably capable machine if you respect its limits. Build a bench with lots of drawers to minimize 'lost' space.... make a top that you can drop on for more bench space... If you can squeeze just a tiny bit more, a 9x36 South Bend or Atlas doesn't take up very much more room and would give you more capability.


I will second that. I used a 3-in-1 machine for a lot of years and the milling head on it was absolutely useless for milling. I used it as a drill press occasionally, but milling was a waste of time, and that's no exaggeration. Steer clear of them if you want to mill. I'd personally rather have a decent lathe with a milling attachment, than one of those Chinese 3-in-1 machines.

danlb
09-25-2015, 02:22 PM
I have the Seig X1 with an extended length table. I thing my table is similar in size to yours. The extended table gives more room for clamps.

I've milled pockets several inches wide and deep.

To hog out a deep pocket, use a drill to remove most of the material before using an endmill. Drills are cheap and easy to resharpen.

Check out these courses developed by the US Army; http://opensourcemachine.org/us-army-courses . They were designed for self study, so you should be able to go through them and get a LOT of information. I used a similar US Army guide to machining when I got my first lathe.


Dan

janvanruth
09-25-2015, 03:40 PM
youtube: that lazy machinist,oxtools, toms techniques
that lazy machinist also has a site, quite recommendable

check out the maximat lathe with the milling column

MrSleepy
09-25-2015, 04:32 PM
Youtube does have some gems.. Dan Gelbart, Keith Fenner ,Abom etc
MIT has a good selection of tutorials aswell (text blatantly stolen from machinestblog)


Machine Shop 1 Machining Skills for Prototype Development (http://techtv.mit.edu/genres/24-how-to/videos/142-machine-shop-1) (Length: 40:32)


Basic tour of the machine shop
Layout techniques (including transferring hole locations)
Basic tools: drill press, band saw, belt sander and grinder
Locating and drilling holes (includes using a center finder and deburring)
Tapping holes (including using a tap guide)

Machine Shop 2 Machining Skills for Prototype Development (http://techtv.mit.edu/videos/130-machine-shop-2) (57:33)


Drilling holes
Special drills for plastics and hard or abrasive materials
Drill press limitations
Bandsaw
Suitable speeds, feeds and materials
Bandsaw setup
Using the drill press vise

Machine Shop 3 Machining Skills for Prototype Development (http://techtv.mit.edu/videos/181-machine-shop-3) (30:02)


Good practice clean up
Small belt sander configurations
Grinder operations and materials
Deburring and buffing
Finishing techniques

Machine Shop 4 Milling Machine 1 (http://techtv.mit.edu/videos/127-machine-shop-4) (50:33)


Parts and controls of a Bridgeport Mill
Quill feed
Axis handfeeds (11:20) backlash explanation (12:15)
Gib locks (14:40)
Power feed (18:33)
Digital readouts (21:07)
Milling machine set-up squaring/tramming the head square (22:37)
Squaring the vise adjusting the vise so the stationary jaw is parallel to the bed (32:33)
Milling machine accessories and workholding techniques (41:15)

Machine Shop 5 Milling Machine 2 (http://techtv.mit.edu/videos/84-machine-shop-5) (1:03:33)


Square and hex collet blocks used to hold/clamp parts to machine features on 4 and 6 sides of a part respectively (1:02)
V-blocks (2:10)
Hold-down clamps used to hold large or irregularly shaped parts (3:40)
Using angle blocks used to hold materials to machine features not perpendicular on a part (6:15)
Drill press vise using a vise within a vise (8:29)
Lathe chuck with vise can be used to hold parts in the milling machine (11:11)
Double sided tape can be used to securely hold a part without distortion (12:00)
Squaring high aspect ratio parts (16:02)
Right angle attachment (23:04)
Slitting saws used to cut slots/slits/features in a part (33:21)
Rotary table used to machine circular parts, grooves, circles, and segments (41:16). A dial indicator (43:20) or Coaxial indicator (47:25) can be used to square/center the table to the X & Y axes
5C collet indexer used to hold collets and to position parts in up to 24 positions (52:42)

Machine Shop 6 Milling Machine 3 (http://techtv.mit.edu/videos/143-machine-shop-6) (42:36)


Squaring a part machining a piece of metal so all of the surfaces are flat, perpendicular and milled to the nominal size (1:00). Also covers using a fly-cutter (4:50) and deburring (8:40)
Squaring a plate (17:52)
Using the edgefinder (32:00)
Drilling holes with a mill (35:32)

Machine Shop 7 Milling Machine 4 (http://techtv.mit.edu/videos/183-machine-shop-7) (23:07)



Reaming holes (1:00)
Boring holes with a boring Head (3:04) also covers using Plug Gages to measure hole sizes (8:54)

Milling a slot (10:45)
Milling a shoulder, conventional and climb milling (17:11)
Cleaning the machine (21:05)

Machine Shop 8 Lathe 1 (http://techtv.mit.edu/videos/144-machine-shop-8) (42:37)


The Lathe components
Turning tools (6:40)
Turning and facing (11:04)
Cutting off a part (22:45)
Drilling (32:20)

Machine Shop 9 Lathe 2 (http://techtv.mit.edu/videos/134-machine-shop-9) (46:15)


Tapping
Boring (7:31)
Knurling with a bump knurler (15:30)
Cutting tapers with the vompound (22:21)
Turning shafts using a live center (26:18)
Single point thread turning (31:03)

Machine Shop 10 Lathe 3 (http://techtv.mit.edu/videos/172-machine-shop-10) (29:00)


Lathe chuck
Lathe arbors (6:42)
Turning between centers (15:40)
Face plate irregular shapes (19:00)
Face plate thin materials (21:13)






Rob

RussZHC
09-25-2015, 04:49 PM
IIRC, and depending on where you are located, there was an ad or series of ads on Calgary Kijiji with the idea of starting up a local hobby shop machining group. IF you are close enough that could be a good source of info and learning.

Welcome.

Jyman
09-25-2015, 05:02 PM
If you are close to Edmonton, there is a metal group that meets every month

krprice84
09-25-2015, 05:33 PM
HOLY SMOKES GUYS!!!

Haha, thanks so much for all of the info.

I'm just about to leave work, so I don't have time to read everything yet, but I absolutely will.

I live in Calgary, Jyman, just fyi. A little far from Edmonton... but at least I'm not in Edmonton :P (little jab there at Edmonton haha). Naw, in all seriousness, I'd love to find a group of people to discuss this kind of stuff with in person, but for now, the forums look like they will be great.

The machine is the tilting column one - I would have loved to found a solid one, but this is what came up, and I got it for cheap (500 bucks, with a whole wack of end mills, some ball mills, a collet set, and a vise). Couldn't say no to that. I'll just make sure I go slower.

1/4" x 1/4" though on steel? wow, I expected to have to go way slower. I'll still take it slow, but that's cool that you can do that much on a very similar machine.

Just on my way to Busy Bee right now to look at some things. i'm thinking of getting a hold down/clamping kit, and a rotary table. Any thoughts on this? I'd really like to be able to machine arcs, and possibly even do some minor "turning" with a rotary table, a 3 jaw chuck, and go slowly around the piece. Is that even possible? There's no room for a lathe here, so until I can get the space for one, or the money for a lathe/mill combo, I'm stuck with this. Any way to make round pieces? (they don't need to be absolutely perfect, not chambering a barrel or anything!)

Thanks again, and I'll reply soon with more questions, no doubt. But any quick advice on what I should pick up at Busy Bee?

Right now I have the mill, a number of end mills, ball mills, etc (some are center cutting some not, for the end mills), I have a pretty big facing end mill that I doubt I'll use, a full collet set, a drill chuck, and the vise that it came with (doesn't look amazing, but doesn't look great). Also have a set of parallel bars (they might be too big for this though, I didn't think about that when I bought them, we'll see tonite), and a set of 1-2-3 blocks.

LMK what you think I need to buy, and especially that rotary table. Any reason to spring for one with a dead center, so I could do cool things with it, or is that silly to think of for a mill this size?

Jyman
09-25-2015, 06:22 PM
The 4 inch tilting rotary table is nice/alright, but it has a little play in it. I use mine for making gears. If i was you I would look at the fly cutters also, it's nice to cover bigger areas faster. I can't think of anything else at the moment. Too bad your down in Calgary I don't know of any groups down there.

sasquatch
09-25-2015, 06:32 PM
Does anyone have a link to the Edmonton Group?? Thanks.

Jyman
09-25-2015, 06:39 PM
The Edmonton group is known as AMEN and I don't think there is a website, but the last Thursday of every month they meet at humpty's on gateway

sasquatch
09-25-2015, 06:47 PM
Lol, AMEN ? Ok, thanks for the posting, have a friend in Edmonton to send this info to.

Jyman
09-26-2015, 05:25 PM
Did you happen to get a rotary table or anything else? if so what one did you end up getting?

krprice84
09-26-2015, 08:33 PM
Did you happen to get a rotary table or anything else? if so what one did you end up getting?

No I didn't make it there in time. Kms had a 4 inch one non tilting, but it had a lot of play in the engagement for the worm drive.

Gonna go out to busy bee on Monday.

Is a clamping/hold down kit worth buying or do you not really need one?

krprice84
09-27-2015, 10:48 PM
I have the Seig X1 with an extended length table. I thing my table is similar in size to yours. The extended table gives more room for clamps.

I've milled pockets several inches wide and deep.

To hog out a deep pocket, use a drill to remove most of the material before using an endmill. Drills are cheap and easy to resharpen.

Check out these courses developed by the US Army; http://opensourcemachine.org/us-army-courses . They were designed for self study, so you should be able to go through them and get a LOT of information. I used a similar US Army guide to machining when I got my first lathe.


Dan

Those courses are great. Not too complex but give enough info to feet going.

I also watched the video above about getting set up.

Unfortunately, my machine has a tiny bit of can't to the table. From the front to back it is tiled by about 2 thou or so. Not the end of the world I guess, but I won't be doing anything that requires 100 percent flat surfaces on this thing. That sucks. Don't think there's a way to take that out with this mill either, because there's only bolts holding the head up, and then there's the big pivot for tilting it. I guess in theory I could try to machine a ring that was ever so slightly angled, but I doubt it would work and I doubt I could do one that thin on this machine.

Ahh well :(

mars-red
09-28-2015, 08:10 AM
Those courses are great. Not too complex but give enough info to feet going.

I also watched the video above about getting set up.

Unfortunately, my machine has a tiny bit of can't to the table. From the front to back it is tiled by about 2 thou or so. Not the end of the world I guess, but I won't be doing anything that requires 100 percent flat surfaces on this thing. That sucks. Don't think there's a way to take that out with this mill either, because there's only bolts holding the head up, and then there's the big pivot for tilting it. I guess in theory I could try to machine a ring that was ever so slightly angled, but I doubt it would work and I doubt I could do one that thin on this machine.

Ahh well :(

From what I've read online, the tilting column type can be shimmed to correct that "nod". If you look at the spec on them, it's pretty poor though. The spec on mine was something like within 0.005". It measured over that (0.007", iirc), but unless it was pretty much zero I was going to tram it anyway so that really didn't matter. As bad as 0.002" of nod is over that short distance, it's still better than most of them seem to be from the factory. With some fiddling you should be able to get it right on, though. I'm not positive, but it looks like the best place to shim might be between the square column itself and the casting for the pivot.