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Low fixtures and lack of Z travel

Houndogforever

Hot Rolled
Joined
Oct 20, 2015
Location
Boring
I have the speedio S700x1 machine and I love it. Recently I have been working on various fixtures for some repeat jobs and I have run into an issue.
If I bolt the fixture plate down on the table, the tools won't reach unless I use extended tool holders which pretty much kills the machining time.

On one fixture, I made 1" round and 1" high legs and mounted the fixture to the interchangeable plate on those risers just to get that high enough to reach.
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Now this next fixture I am designing is another small part and will be a low lying fixture. I will need to raise this one up about 1-1/2". I would rather not put a 1-1/2" piece of plate on top of the 3/4" quick change fixture plate.

What do you guys do to get your reach on small parts?
 
I'm kind of in line with Bobw. On my 30 taper mill I have an 8" vise that in the 7+ years I've owned has never been off the table. Vise parts go in the vise. Fixture plates go in the vise. Works well for my work type and flow which is very low quantities, often one of a kind parts.
 
What do you guys do to get your reach on small parts?

TL;DR Everything goes in a vise.

For easy stuff I just put fixture plates in a vise. If I’ve got a lot of load I use Talon Grips on the fixture plate or mill in a dovetail.

I also made up a OV pallet with a standard grid on it for parts that want step clamps and such.
 
The thing is, I'm trying to get away from vises and more into dedicated fixtures. The old fadal has no problem getting down onto a 3/4" fixture plate, but el speedio can't reach.
So that means I can't use the same fixturing on both machines.

I also only have 4-1/2" orange double vises so I would need to purchase at least one 6" double vise to be able to use vise pallets for the fixture.

I guess for now I will ponder on it some.

As to why I am making fixures, well, if I make this part once, I will more than likely be making it for the next 20 years, so I might as well do it right. Being a manufacturer has it's advantage over job shoppinng.
 
Now this next fixture I am designing is another small part and will be a low lying fixture. I will need to raise this one up about 1-1/2". I would rather not put a 1-1/2" piece of plate on top of the 3/4" quick change fixture plate.

What do you guys do to get your reach on small parts?

Just put a 1.5" thick plate beneath the plate that receives your fixture?

Your fixtures probably can't get any thinner than you are currently doing, may as well "fix" the problem by making the whole thing sit higher off the table.

One thing I HIGHLY doubt is possible, but can you extend the travels of the Z axis down further, or will way covers/ballscrews/whatever collide? We have an older 1300mm machine that should be roughly 51.2" of travel, that we were able to weasle out some extra inches in xy. It now travels 55.6" and we might be able to get another .25 each way if we were daring...

Again, I highly doubt you could get much if any, and I certainly would doubt you'd get 1.5" in this manner.
 
We use Miteebite quick change pallets.
They are similar to Jergens ball lock but more rigid.
IIRC, receivers are $600 each and blank pallets are $300. (Psst..you can make your own pallets. :D)
Changeover time is 20 sec. if you hustle. The receiver and pallet raise everything 2" total.
What we did was drill a 1/2-13 grid hole pattern on 1" centers across the entire pallet, and then a dowel pin grid as well.
Then we put a vise on a pallet, indicated it, and never took it off the pallet.
 
Maybe go 'whole hog' on the fixture plate idea and get a couple of the Pierson 'Pro Pallet' systems to permanently mount on the machine table? Build your fixtures to all mount on top of that... You could even make bases for your vises that mount on top of the pallet system as well. Would act like a permanent riser without the massive weight and get you some extra capability at the same time...
 
Good ideas guys. Thanks for the input.
I usually have 2 vises and my rotary Raptor on the table at all time.

But I'm finally starting to use my trunnion table so both vises need to come off then.

I can't wait till my son takes over and then I don't have to stand out there and work any longer.
 
I made some 4" legs from a 2" thick piece of aluminum. The riser legs have dowel pin holes for alignment. 1" thick fixture plates drop onto the dowel pins with 3, 3/8 cap screws per side. The center of the fixture has a bored hole for probing work offset. I have 3 pallets(for now) with different designs to hold parts. After I machined the riser legs, I bolted them to the table and gave them a skim cut for flatness. For the fixture plates, I face and drill the dowel holes, then bolt to the riser legs and machine work holding features.

It pretty easy to switch from fixture to vise and the whole assembly is pretty light. I made these to fixture 6 parts at a time with 3 different parts. Repeatability has been very good so far.
I didn't like the thought of running full rapids with 2 Kurt vises on the table of my speedio. Maybe that's a none issue, I'm pretty new to this. But all the small features and 0-80 holes, I want to haul ass. It's been great so far.

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