DIY Linear Rails

[Geof]

"just convince my wife that my machine must go in the garage, instead of her bug...."

That is easy; your machine will be big enough to straddle the bug. Just put a 3 axis head on it, a big buffing pad in the spindle and bingo! you have an aotuomatic car polisher.

[JerryFlyGuy]

That is easy; your machine will be big enough to straddle the bug. Just put a 3 axis head on it, a big buffing pad in the spindle and bingo! you have an aotuomatic car polisher.

AHHH... see now here's someone who's speaking from experiance.. Geof, your skill's as a negotiator must be second to none

However... the wife.... is a practiced negotiator also..and her field of expertise is in legal matters.. so you guys can imagine how many arguements I win...

Jerry

[WhiteTiger]

Jerry, the acraglass is sold by fluid volume, not by weight. Try this link and scroll down to bulk quantities.

You can get a 1 gallon volume for around $150. If you know the cubic volume of you application that figure may turn out to beat the moglice (a product I've had no experience with). At least it should be competitive I think... I can't imagine you're expecting to use more than 4 gallons of seating material



Tiger

[Robyn]

Also check out www.teausa.net for the linear slides they offer.

[KTP]

I don't think it is quite proper to spam every group with the teausa link.

[Robyn]

Sorry KTP - Error on our part - new person - won't happen again.

[BobWarfield]

I'm coming into this one late, so the choice of moglice alternative may have already been made. I did want to point out that the madvac kayak guy (love that name) used West Marine epoxy with steel and aluminum dust filler. Boat epoxy is very sophisticated stuff and West seems to have good prices on the stuff. I certainly read about it being used in a lot of places other than boats.

I'm continuing to watch all this with some interest. Getting these rails mounted flat is a problem I'll have too. While I am curious about what I'll call the moglice approach, I'm not sure it's the right choice for me. I have a mill for one thing, but another thought comes to mind: why not cobble together a surface grinder for this purpose using a granite surface plate? Seems like your task is then to feed the square tubing or whatever you want to surface through taking very light cuts until you've got a flat bed for the rail. Alternatively, you could rig a fly cutter in a similar way and have a go, perhaps even cutting the side alignment surface as well.

The bedside reader series talks about cobbling together a surface grinder in this fashion. Heck, you can buy the real thing relatively cheaply compared to what this project will come to.

Too crazy? I dunno, but I'll throw it out there anyway.

Best,

BW

[JerryFlyGuy]

Thanks Bob, I have actually progress on this and have got 5lb's of Devcon sitting about 5' from me right now [ still in the can ]. This whole discussion has kinda moved to another thread about laying out centerlines. I've got some idea's on how to level the rail [ I think they are actually posted on this thread somewhere also] but will keep ya'll informed as to how things progress.

Jerry [garage painted.. and stuff moved back inside.. making Haste.. slowly..]

[vid1900]

I didnt see anyone mention using actual drilled support rails, that are actually made to support the linear shafts. I could not see any easy way to link, but go to:

www.mcmaster.com

and then goto cat page # 991, they are at the bottom half.


Even more tasty, on cat page # 992, they have one piece 1" shafts (ceramic coated aluminum, stated to be as hard as steel) with the support rails already attached to them for $58 in 9' lengths and $77 in 12' . These are so much cheaper than anything on ebay.

thanks

vid

[JerryFlyGuy]

I think round bar rails are ok, and would be a good half step between the DIY and good linear THK rails, I've not really paid much attention to them simply because for the price, you might as well go all the way to a good linear rail. In my application bar rails would have to be supported along their entire length, and when you start adding up the price, you might as well go for the little bit extra bit and get the added accuracy of the THK style stuff.


Jerry [pockets now empty after these 2 cents.. and a monster milling machine ]

[Geof]

... on cat page # 992, they have one piece 1" shafts (ceramic coated aluminum, stated to be as hard as steel)

The coating may be as hard as steel but the substrate 0.002" below certainly is not.

They do specify they are for use only with plain bearings.

The use of the term ceramic coating may be a bit of hype. The surface of hard coat anodized aluminum (all anodized aluminum for that matter) is aluminum oxide; hydrated alumium oxide if you get technical. This is a metal oxide; the principal constituents of ceramics are metal oxides so the surface of hard anodized aluminum could be described as having a ceramic coating.

Maybe they are applying some esoteric form of ceramic coating but at the prices they give I am dubious.

[Allan]

Whatever happened to this thread? Was this monster ever built, or were the participants only theorizing? Philosophising? Jabbering?

[JerryFlyGuy]

Whatever happened to this thread? Was this monster ever built, or were the participants only theorizing? Philosophising? Jabbering?

I suppose, being this is a forum... Jabbering is to be expected....

And yes the machine has been built and is being used regularly to build parts for various projects..

[lgalla]

Hay Jerry,I am back in business.
I just got some NIB's.3-46"THK rails and 6 blocks THK HSR-20.I would like to have one rail cut in half and buttjoint to the outher two,giving 69" perfect for the Y axis.How does one get perfect but joints?EDM? Your monsiter must have had some butt joints.what machining was necessary?
Larry

[lgalla]

ALLEN you are new to the forum and should realize it takes time for research to build a machine.Our top posters.Jerry,jGer,Geof,Altheman have a wealth of information all 4 free.
These guys are brillant.Hope they can answer any of your questions.
Larry

[Allan]

Hi Jerry and Larry,

>>ALLEN you are new to the forum and should realize it takes time for research to build a machine.Our top posters.Jerry,jGer,Geof,Altheman have a wealth of information all 4 free.
These guys are brillant.Hope they can answer any of your questions.
Larry >>
__________________

>>I suppose, being this is a forum... Jabbering is to be expected....

And yes the machine has been built and is being used regularly to build parts for various projects..>>

Judging from the response to my question it seems as if my post was perceived as being derogative. If this is the case, I apologize. Seeing that this thread ran so long and the last post was on 04-25-2006, and it ended so abruptly, I was curious to find out what happened to the project. Some photos of this machine would be interesting to see.

Yes Larry I have come to realize that these things take time; I have been milling ideas around in my head to build a CNC router since I joined this forum in 2005 and have just recently got around to buying 3 steppers and a controller for a to-be-built machine although I am still painfully in the process of getting AutoCad mastered in order to be able to draw/design my linear rails.

Kindly accept my apology if offense has been given.
Allan

[JerryFlyGuy]

No worries Allan, reading anything online can soo easily be misconstrued.

Anyway, I've yet to post any real pictures. It's hard to get them as the machine fills the space it's in [I'd need a fish eye lense to get it all] however I do have a couple video's on youtube

"http://www.youtube.com/watch?v=nQytmfvUc7M"]YouTube- 10x20 Mill

"http://www.youtube.com/watch?v=vQSdxaGOG5o"]YouTube- CNC Mach3 Router-120ipm 0.5"EM in Aluminum

Larry, I didn't do too much when joining the rails. I just made sure they were ground nice and flush [just visually] and then assembled them..

They've got over 1000hrs on them so far... w/ no issue to date. When the machine moves across them I can't detect any jolts or bumps... I guess that is one benifit of having as heavy a unit as I do

Fwiw

[lgalla]

Jerry thanks for the videos.Good to see a build in action.