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View Full Version : Squaring; wonder how this would work?



QSIMDO
09-01-2006, 04:02 PM
I believe there's a picture around here of the bottom of a Tormach column which apparently shows adjusting screws instead of using shims for squaring.

Is that correct?

So how would it be if I drilled and tapped the IH column for such adjusters?

My greatest concern would be torquing down the column bolts and snapping a corner off the column base. Perhaps though if the adjuster screws were close enough to the column bolts the force would be directed straight down through them and not so much at an angle if the adjusters were some distance away.

Thoughts?

miljnor
09-01-2006, 04:40 PM
bolts are convenient but shims are the sure way to go and typicaly (unless you crash alot) this process dosn't happen much.

I would stick with the shims and ditch the convinient/lazy way!

Beside I don't recall ever having a shim back out on me but a bolt???

QSIMDO
09-01-2006, 10:15 PM
Well...point taken, but let's not ignore that a seemingly highly accurate machine uses the adjusting bolt method.

Not born of laziness...convenience I'll readily admit to.
Rather like "adapting, improvising and overcoming" wouldn't you say? Which, with what I have left of vision and dexterity is getting harder all the time!
You bet I'll try anything that makes it easier! ;)

miljnor
09-01-2006, 11:21 PM
That was basically off the cuff, so I don't know what other machine manufactures do. But if someone uses that method on commercial machinery then its probably good to go!

I addmit to being lazy all the time, my wife disagrees but hey its human nature to do the least work for the most benifit!

Cruiser
09-02-2006, 07:43 AM
I drilled and tapped mine for 5/8 fine set screws, works great, then find a feeler gauge to slip in next to bolt before torqueing it down and do so in stages. My collumn is within .0005 now and i figgure on checking it again after it gets shook in some. I got pics to show where i drilled.
I have developed some proceedure/technique to get it righ. only back off bolt so spring washer has enough tension to hold collumn from tipping unwanted, then do tramming, if set gets too tight then back off bolt 1/8 turn or so and further adjust, lastly steal feeler of appropriate fit to jam into gap under bolt and then as you apply torque to bolt check tram and readdjust to complete. firstly tho set slides parralel to table axis as sets will get a bite into base not allowing rotation later on. if done correctly it'll be strong enough to take it all, and the feeler jammed under bolt area will aid in minimizing required readjustment as torque is applied. this is what i did. Also a not on drilling, go in steps starting with a small drill and use a drill guide for every step all the way up to tap drill size then use guide to start tap as well or it'll wander for sure.

QSIMDO
09-02-2006, 09:13 AM
Excellent.
I'm in for that.

miljnor
09-02-2006, 04:52 PM
i just trammed mine in, and although it is a custom made collum it is similar in construction to yours. Wish I would have put set screws like yours in for later. Although truthfully when i trammed mine in with shims it take 2 try's and got it perfect. That wont happen again!!!

Adobe Machine
09-02-2006, 05:45 PM
Thats a very good , professional way to align any part on a machine tool,I doubt that you will have to readjust veryu often unless the casting is soft. Nice job !


Adobe ( old as dirt )

philbur
09-08-2006, 07:05 AM
The Tormach doesn't have adjusting polts to square the column. What you are probably mistaking for adjusting bolts is the dowel pins. These are used to ensure realignment after disassembly/reassembly. In my opinion adjusting bolts risk introducing a degree of unwanted flexibility, unless the design is very cleverly implimented.

Regards
Phil


I believe there's a picture around here of the bottom of a Tormach column which apparently shows adjusting screws instead of using shims for squaring.

Is that correct?

So how would it be if I drilled and tapped the IH column for such adjusters?

My greatest concern would be torquing down the column bolts and snapping a corner off the column base. Perhaps though if the adjuster screws were close enough to the column bolts the force would be directed straight down through them and not so much at an angle if the adjusters were some distance away.

Thoughts?

QSIMDO
09-08-2006, 04:16 PM
, unless the design is very cleverly implimented.
Phil

Point well taken Phil, which is why I intend to inject Moglice into the joint between column and base once squaring has been accomplished to whatever degree I'm capable of giving it.

A depressing thought in and of itself! ;)

BobWarfield
09-11-2006, 12:55 PM
Moglice would be one approach, though it would seem hard to eliminate pockets in the process, and I'm not sure how things would go if you ever needed to get it apart.

How about just using shim stock once you have it adjust where you want it? It's still got to be tremendously easier to adjust with the set screws than going for shims alone.

Best,

BW

QSIMDO
09-11-2006, 04:36 PM
Bob,
When you consider how much of the column and base are NOT in contact when using shim stock alone even poorly dispersed Moglice would have to be better.
However, this application is ideally suited for the product and anywhere you don't want it to stick just apply their release agent.

Set screws, trammed, Mogliced...done & done, Bob's yer cousins father!:D

Len

BobWarfield
09-11-2006, 06:56 PM
Congratulations!

Best,

Bob (no relation despite the rumors) Warfield (chair)

Ron111
09-11-2006, 07:18 PM
What's Moglice?
Sound kind of messy.

Ron (I'm not related either)

BobWarfield
09-11-2006, 07:25 PM
Moglice is very cool stuff invented for machine refurbishing. Think of it as epoxy with teflon embedded. It is typically used to refurbish ways, but can be used for other precision surfaces as well. QSIMDO has found a clever application.

It can be injected, and it can also be molded. JerryFlyGuy is using something similar to try to create an absolutely flat mounting surface for his linear rails on his big gantry project.

Best,

BW

PS Went off on one of my many qixotic web searches to review my knowledge of Moglice. How about this machine tool maker that is using QSIMDO's exact approach on a high dollar machine: http://www.mech.utah.edu/~bamberg/research/StarToolGrinder/EberhardBamberg-PhD(05-2000).html

The guy's PhD thesis is something I'm still downloading, but I thought this was interesting.

QSIMDO
09-13-2006, 06:38 PM
QSIMDO has found a clever application.


Oh, hell no, I can't take credit for that!

Moglice has been used for that for many years.

Check it out...http://www.moglice.com/newsite/frames/staticframe.html

ozzie34231
09-21-2006, 11:03 AM
Of course if you want the best possible rigidity, set up with shims, take it apart and scrape the sides opposite the shims. You'll nedd a hoist to lift the column a dozen times or so, but you'll get the most solid setup.
Jerry

miljnor
09-21-2006, 12:53 PM
I only have one word for that statement man:

Hobby! :D

or maybe two words: too lazy :D:D:D

Harlow
09-26-2006, 08:39 PM
Epoxy + Iron Oxide. You can mix Epoxy with Iron Oxide, Aluminum Powder or other metal powder to make a paste. You probably have enough sitting around your grinder. You should get about 50/50 by volume using off the shelf epoxy as it is rather thick. Thinner epoxy or heating thick stuff and you can get a higher metal ratio. Don't go over 70% metal to 30% epoxy.

Once you have it shimmed or adjusted where you want, raise it up +- .004. Coat the bottom of your column and the base where it contacts with a good coat of car wax, paste floor wax or grease. That will keep it from sticking.

Shove the epoxy in with a feeler guage or shim stock. As the epoxy cures it heats up and expands a little. It will go from liquid to gel to semi-solid to solid as it cures. You want to drop the column back down between the semi-solid and solid stage. Depending on the epoxy you use the time will vary. Do a test mix about the same thickness as the void to fill first. Thickness does matter. It effects the cure rate. If you put an IR temp guage on it you will see the temp rise. Check it occasionally and when your fingernail can still make an easy impression it is right. That's when to drop and tighten.

Don't use for at least 24hrs. 48 is better. If you pack it in good you will have 100% contact area. Don't use the 5 minute Epoxy. Use a medium set. Epoxy is very temp sensitive. You can thin it easily with a heat gun. Heat also reduces working and cure time.

Harlow
http://cncbridges.com/

philbur
09-27-2006, 03:28 AM
Sounds like a very dodge procedure for a column that needs to be perfectly square with the table. If you mix solid material in the epoxy and this solid is between the shim and the casting then the squareness result will surely be effected. Also you will never extrude the last fraction of epoxy from between the casting and the shim so this will effect acuracy also.

Regards
Phil


Epoxy + Iron Oxide. You can mix Epoxy with Iron Oxide, Aluminum Powder or other metal powder to make a paste. You probably have enough sitting around your grinder. You should get about 50/50 by volume using off the shelf epoxy as it is rather thick. Thinner epoxy or heating thick stuff and you can get a higher metal ratio. Don't go over 70% metal to 30% epoxy.

Once you have it shimmed or adjusted where you want, raise it up +- .004. Coat the bottom of your column and the base where it contacts with a good coat of car wax, paste floor wax or grease. That will keep it from sticking.

Shove the epoxy in with a feeler guage or shim stock. As the epoxy cures it heats up and expands a little. It will go from liquid to gel to semi-solid to solid as it cures. You want to drop the column back down between the semi-solid and solid stage. Depending on the epoxy you use the time will vary. Do a test mix about the same thickness as the void to fill first. Thickness does matter. It effects the cure rate. If you put an IR temp guage on it you will see the temp rise. Check it occasionally and when your fingernail can still make an easy impression it is right. That's when to drop and tighten.

Don't use for at least 24hrs. 48 is better. If you pack it in good you will have 100% contact area. Don't use the 5 minute Epoxy. Use a medium set. Epoxy is very temp sensitive. You can thin it easily with a heat gun. Heat also reduces working and cure time.

Harlow
http://cncbridges.com/

Harlow
09-27-2006, 08:38 AM
Also you will never extrude the last fraction of epoxy from between the casting and the shim so this will effect acuracy also.

Common sense should tell you not to put the epoxy where the shims are. Filling voids would mean the area not covered by the shims.

Harlow

http://cncbridges.com/

Cruiser
09-27-2006, 08:54 AM
With my system of 5/8' fine set screw, and the cannibalism of some feeler gauges, and torque to 90 in steps adjusting as you go you will find it to be solid ! just keep enough of the split lock washers compressed yet loose enough to allow the set to move collumn. I only needed feelers of .002 to .004 as i recall maybe more but it wasn't much, I've pushed a large end mill in some steel to test it and the only lacking was in the 'z' saddle and i've tightened it since, and of course my machine enclosure did a bit of a dance and resounded the music, but the collumn held fast and solid ! If I feel the need to adjust it later on, it'll be easy and i don't have to chip away epoxy and i'll be done before you will !