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Looking good!

Your idea about making the parts from wood first is not a bad one. Over at CNC zone, this fella build a machine completely out of MDF to start with, only to have this machine, cut all the parts for his aluminum machine after that!



If you stick to some good tolerances while you machine the wooden parts, that machine will then give you much better tolerances to cut these same parts again, out of aluminum (being careful on the speeds and feeds of course....keeping it slow, should not be an issue).

Also, I do not know what the "run out" of the porter cable router is. You can mount it, and with a dial caliper, find this out. A thousand of an inch I would think would not be an issue.

Excellent work so far!

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-CyborgCNC
http://www.cncguitar.com
https://www.facebook.com/CncGuitar

Thanks much...
I've contemplated MDF for the temporary material since it is very stable stuff, at least until it gets wet. I've also thought about using some phenolic board, or even some HDF laminated to 1/2" thickness. It would really make life easier to not have to pay someone a ton of money to cut the aluminum.

Well...time to head down and try to do some work on the gantry. Woo-hoo!

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I bought my mill as a small home made rig, which was made out of MDF. It idd fine as far as tolerances (for wood working, anyway).

I am upgrading my mill to a larger size, and continued with the MDF design, just larger. The MDF part of the equation is fine, but I am having problems witht he precision ground rails that I bought having some "spring" to them. I bought these rails and the linear bearings to ride on them for the table rails, but over the 48" stretch of the length, it bounces. The rails are only supported on each end of the rail (a 3/4" round steel bar) and this is part of the issue I am experiencing. I havent decided how I am going to address this issue yet.

I may go ahead and get what i have running, then use the working mill to help build a better rail system out of aluminum. I have several pieces of 3/4" corian laying around also and have considered using this as part of the new setup.

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Reguards,

Ken H

Ken…have you considered using the open linear bearings with the continuous support rails. They work exceptionally well as long as the table that they lay on is stiff.

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Rich S

"The inconvenience of poor quality will linger long after the thrill of a bargain has been forgotten"

The continuous support rails is most likely what I am going to have to do. The bearings that I have will not work on that type of rail as they are solid and dont have the opening for the rail supports. This means that I will have to replace those as well, but they arent that expensive on eBay. I actually found a guy selling CNC stuff on eBay that is located here in Florida and I get things from them really quick. Their prices arent bad either, so most likely I will go with them for the continuous support rails.

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Reguards,

Ken H

Ken,

These folks have Hiwin linear rails and sleds at a pretty good price...Automation Overstock
I may buy some just for any future projects I may come up with...

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Here's a couple pics of the progress on the gantry.

In the second photo, it shows a 1/2" aluminum plate up against the upright that still needs to be machined and drilled out to attach the gantry to the linear rails.

The last part was finally ordered this morning...a motor shaft coupling to attach a 6mm shaft to a 1/4" shaft, that will fit within a narrow space. The 1/4" side will have to be reamed to a 1/2" diameter for my purposes.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

This is inspiring me to build a new gantry for my machine. I'll be keeping and eye on your progress. Thanks.

Man Don that is looking great!
Wish I new what I was looking at

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Lance@LuthiersForum.com

I am confused, whats this part?

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Support the OLF! Bookmark our STEWMAC link Today!
Lance@LuthiersForum.com

Those are called "paper towels" Lance. Haven't you ever seen those before? I mean, come on now!

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I refer to them as "crying towels". Sure is looking great Don!

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tim...
http://www.mcknightguitars.com

Well, here's a picture or two to show the latest progress. The linear rails for the gantry are finally installed, and the plates that join the gantry to the base linear rails are machined. Also, the plate to attach the Z-axis to the linear rails is done. I was going to hire a machinist to do this stuff, but it turns out that aluminum plate drills out so easily that I was able to accurately do these myself. It was pretty tedious work, but the results were excellent, if not for a couple minor hicups.

I also had to drill out a flexible motor coupling, which was the only one I could find that was small enough for my needs, yet that could be modified to shaft size. It was tricky, in that it flexes do to a series of slits in the side. I had to wrap it in metal aluminum tape, and squeeze it into a 1" hole in a piece of scrap movingui to hold it, and even then I had to use a pair of vice grips to keep it from turning. Somehow, I got it drilled to within .01" of the correct internal diameter. I got lucky...

Pictures tonight. Even if they are pretty boring.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

is the coupling keyed onto the shaft? or is it held via setscrew? you'll need to do one or the other to prevent backlash...

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http://www.PeakeGuitars.com

It's a clamp-on model. I suppose I could drill and tap for a set-screw, but it's pretty darn tight, and I doubt it will go anywhere. Two tightening screws per end. Very very tight fit.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Not sure what type of clamp collar you're using but I would doubt that it would slip especially if the bore is sized precisely to the shaft. Might actually be better if it did slip in the event of a crash but the servo over-current limit would probably kick in anyway.
Speaking of crashes they always say to make sure you have a hard-wired Estop and not depend on a software Estop.

You know it! That's the one thing I have yet to order.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Here's those pice I promissed....the plates I made, the linear rails attached to the gantry horizontal, and the little motor coupling.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Looking good Don. Those linear slides look like THKs??? There’s nothing like “pulling out all the stops”, Way to go!!!

I am as envious as one could be…keep bringing on the pictures.

One more thing, don’t forget to plug those rail holes when you’re done. I recently had to remove a rail and every Allen-head bolt had sawdust packed in it, what a pain in the neck that turned out to be.

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Rich S

"The inconvenience of poor quality will linger long after the thrill of a bargain has been forgotten"

Yep...those are THK HSR20's. I bought them off eBay. I think I'm going to have to replace the trucks though, as they are pretty sluggish. To me, linear rails are supposed to be slick and fast, and these take some effort to get them moving. It makes me wonder if they are over-greased, or just worn beyond their life. Not looking forward to the cost of replacements though...it might be cheaper to by new Hiwin rails or the like. My other set of rails are IKO 15mm, and they are so much smoother and faster than the 20mmTHK's...that the THK's must be worn out. I wonder if they can be rebuilt rather than replaced...

What do you mean by "plug those rail holes"? Can you do that and not interfere with the function?

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

I just checked the McMaster-Carr catalog and they call them “Rail mounting hole plugs” Cat # 6709k9. They just pop in and they don’t interfere with the normal operation of the guide blocks.
If your guide rails are mounted so debris won’t collect in the holes you may not need them but after having to deal with cleaning out Allen-heads for a couple of hours, I’ll use them no matter how the rails are mounted.

As far as the worn issue, it is possible that someone used the wrong type of grease.
How do they feel when in motion?
Do they feel smooth or are they rough and how much play is there?
THK’s will have next to no play in them when new.

Also getting you rails parallel is critical. IMO it is the hardest part of building a machine. The more accurate and precise guide blocks are the more critical the alignment must be. It’s sort of a love, hate thing that I have for these types of linear motion slides.

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Rich S

"The inconvenience of poor quality will linger long after the thrill of a bargain has been forgotten"

We used epoxy to fill the bolt and dowel holes in hardened ways year ago. Normally the bolts and dowels came up from the bottom so this wasn't an issue.
Might suggest a technique for aligning your ways for parallelism: Tighten the "guiding" way after it is in correct geometric position and leave the "floating" way a little loose. Slide the carriage along the rails and begin tightening the bolts on the "floater" as you're sure it's aligned as indicated by free motion of the carriage on the ways. This, of course, establishes the distance and parallelism between the two ways.
The tightness in your blocks could be an indication of heavy preload models provided it is not rough. The wipers might be causing the friction?

Parallel doesn't seem to be an issue here. The 8020 aluminum extrusions are extremely precise, and the nuts self-align in the slot. When the joining plate was bolted on to the rails, there was no discernable difference down the entire length. I really thought there was going to be an aignment issue, but there wasn't. How lucky was that? ! ? !
A good friend told me that the stickiness of these rails may not be that much of a concern, as some rails are designed to work better under loads, and with a 600 oz/in motor driving a 5:1 screw, that's a pretty strong advantage for torque, in the neighborhood of 200 lbs... I don't think there will be much of an issue there. I could sell these rails on eBay, and get a coup;le hundred for them, and buy some new rails, or I could replace the trucks...for about $350. Yikes!

Thanks for the part number Rich. Did you ever consider just blowing out the grease from the cap screws with air pressure? I like the plug idea better...

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."

Compressed Air was my first course of attack. I was able to get the majority out but there was still some residual that remained packed into the corners that would not budge. The bolts were button heads, so the sockets weren’t all that deep. Why the person who built this machine didn’t use socket cap bolts I’ll never know??? Anyways the residual would not allow the Allen wrench to seat deep enough to grab enough of the bolt to put any torque on it. These bolts were really in the for keeps. So before I stripped the heads on any of them I put a drop of WD-40 in each bolt and let them soak, then I used a dental pick and cleaned them out. I was then able to get the Allen wrench in deep enough to get the bolts out. After all that I replace the old bolts with the right bolts that should have been used in the first place.

Nelson…I was referring toward getting the holes drilled correctly in the table. I forgot that Don is using aluminum extrusions so now it’s just a matter of getting the extrusions parallel which shouldn’t be to difficult.

Speaking of drilling accurate holes, I want to share a quick story…my best friend owns a machine shop. He bought a new EDM machine and needed to make room for it, so he decided to get ride of a machine that he hadn’t used in the last 10 years. It was a Swiss made Jig Borer. He bought it new and I am guessing that he paid some where in the neighbor hood of $100,000 for it, he wouldn’t tell exactly how much but he said I was close. He offered it to me for free, but I didn’t have a place for it. This thing is heavy, huge and requires 3PH power so to turn it down. I considered it a “white elephant” This machine he tells me, will drill holes that will hold a millionth of an inch. It uses optics for alignment. The perfect machine to build a CNC. I could kick my self in the head.
Maybe I should post this in the “what’s your latest goof?”Thread.

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Rich S

"The inconvenience of poor quality will linger long after the thrill of a bargain has been forgotten"

Nah....overkill. Considering how much play there is in a 3/16" hole for a 3/16" bolt, I don't think you need that kind of accuracy. Oddly enough, I was nailing holes almost dead center with just a simple drill press. When cutting a mounting plate, there has to be a little slop to adjust for plumb and level anyway. Besides, the real world doesn't allow for that much perfection when putting together an assembly.

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"I want to know what kind of pickups Vince Gill uses in his Tele, because if I had those, as good of a player as I am, I'm sure I could make it sound like that.
Only badly."