[Falcon69]

I just got done looking at my HiWin profile rails. I noticed that there is a HiWin logo laser etched on them with an arrow on each side of the logo, pointing the same direction.

Does this mean that the arrow needs to face up when I mount these rails?

Also, I've noticed that some commercial machines mount their rails so the Gantry sits right on top of them, Like the Thermowood machines. Others, like the Weeke, mount their rails on the side, like I have my machine designed for. Is there any advatage to mounting them like the Thermwood machines have there's?

I was thinking for the dust factor, to mount them on the side of the CNC frame.

[DonFrambach]

I just got done looking at my HiWin profile rails. I noticed that there is a HiWin logo laser etched on them with an arrow on each side of the logo, pointing the same direction.

Does this mean that the arrow needs to face up when I mount these rails?

Also, I've noticed that some commercial machines mount their rails so the Gantry sits right on top of them, Like the Thermowood machines. Others, like the Weeke, mount their rails on the side, like I have my machine designed for. Is there any advatage to mounting them like the Thermwood machines have there's?

I was thinking for the dust factor, to mount them on the side of the CNC frame.

The arrows are supposed to point to your datum line. I found the mounting instructions on pages 10-16 of the HiWin catalog to be very interesting. Here's a link: http://www.file-vault.us/pdfs/hiwinguideway.pdf

[Falcon69]

hmmm, I didn't design it using a datum line.

Thanks Don, I'll have to do some more reading.

[DonFrambach]

hmmm, I didn't design it using a datum line.

I have no personal experience mounting HiWin rails but my take from reading build logs here is that most people don't use a datum line and seem happy with their results.

[Falcon69]

what about the way I have them planned to be mounted? With them on their side.

[Falcon69]

Hmm, doing alittle more researching, the Multicam machines also have their rails mounted like I had planned too. So it must be fine to mount the rails that way.

[louieatienza]

According to THK for their 4-way LM bearings/rails: "each row of balls is placed at a contact angle of 45° so that the rated loads applied to the LM block are uniform in the four directions (radial, reverse radial and lateral directions), enabling the LM Guide to be used in all orientations."

I believe in general if your LM blocks/rails have 4 bearing races you should be able to mount them in any direction....

[ger21]

Some types of rails have higher load capacities depending on orientation. For a small homebuilt machines, the loads are so small that you won't notice a difference.

Our Morbidelli uses 30mm (maybe 40?) rails mounted on the back side, and the 2000+ lb head cantilevers nearly 6ft toward the front.

[louieatienza]

Some types of rails have higher load capacities depending on orientation. For a small homebuilt machines, the loads are so small that you won't notice a difference.

Our Morbidelli uses 30mm (maybe 40?) rails mounted on the back side, and the 2000+ lb head cantilevers nearly 6ft toward the front.

A firend of mine has a Biesse Rover in their shop also with a cantilevered gantry; pretty crazy when you think about it how much weight is slung whne the carraige head is at the other end... and those spindles have to weigh quite a bit....