Vac Sys SE Vacuum Clamping Unit- Will It work At Higher Altitudes?? Buy Or Not?

[JFelchlin]

I’ve increasingly considered buying Festool’s Vac Sys SE Vacuum Clamping Unit.
I’ve read the many glowing reviews on the FOG – And can see where it would add to my ease and speed in my woodworking.
Wanting to be thorough in my research – I went to the Festool USA web site –
And downloaded/read thru the product’s Operation Instructions PDF.
The Trouble Shooting section (page 16) details: Problems – Causes – Solutions.
Problem:
“Required vacuum is not attained, indicator on the vacuum gauge [1-2] in red sector.”
Cause:
“More than 6500 ft (2,000 m) above sea level.”
Solution:
“Usage prohibited. Vacuum cannot be attained, expect device malfunction!”

So Here’s My Question:/b]
I live at 7,435 ft (2,266 m) above sea level (Colorado).
It looks like – According to Festool – This unit won’t work in my shop.
My local Woodcraft store don’t know – One way or another.
I really don’t want to "drag it home" – Set it up – And then have to take it back to the store.
Should I go ahead and buy it? Or just forget about it?
Your expertise and input - Would be greatly appreciated.

Thanks ahead,
Joe

 

[tjbnwi]

Mine worked fine in Highlands Ranch. I recall them mentioning just over 5900 feet above sea level.

Tom

 

[Svar]

Ambient pressure at sea level is 101 kPa. Festool pump is rated 15 kPa, i.e. it can generate 86 kPa static pressure drop.
Ambient pressure at your altitude is 78 kPa, so the pressure drop can't be more than 78 kPa.
Your clamping pressure will not be as good as at sea level, but I don't see how it can be damaging to the pump.

 

[Gregor]

The pump will have it a bit easier to pump against the ouside air pressure, so it'll possibly generate a higher (or lower, to be precise, when measured in mbar absolute) end pressure - but might not generate the same pressure differential as on sea level.

As the clamping force is a function of the pressure differential between the outside and the (lower pressured) inside of the suction cup (times the surface area), having a reduced outside pressure (you have ~80% of what is at sea level) will result in a reduced clamping force.

My guess would be that at your height you'll end up with somewhere between ~3/4 to ~2/3 of the clamping pressure the system can generate at sea level. In case you havn't had bought it yet you might want to think about skipping the festool VAC-SYS pump (that cuts out around 300mbar absolute, in case I read the spec correctly) and get one that can generate

 

[Jesse Cloud]

Mmmm, I dunno.  7,500 may be pushing it a bit.  I have a friend who gave up on vacuum veneering at 8,000 and clamping would need even more strength.

I work just shy of 6,000 and mine has no trouble.

Unless you find someone using a Vac Sys SE at that altitude, I guess it would have to be a matter of try one and take it back within 30 days if it doesn't work.  Setup is trivial, won't take long to find out.

If the local woodcraft has a demo unit, maybe they would let you borrow theirs for a few hours to test it....

Let us know what you find out!

 

[JFelchlin]

Tom:
Thx for the input. Good to hear from a fellow Coloradan.
Wikipedia lists the altitude of Highlands Ranch, CO as: 5,920 ft -
Which is well under the 6,500 ft Festool working limit for their Vac Sys.
At 7,435 ft, my place is 25.6% higher than yours -
And... 14.4% higher than 6,500 ft Festool stated limit.
Hence, my concern - And search for more info -
Before: "round tripping" 80 miles - Buying - Installing/Testing -
Then having to return the product to Woodcraft (another 80 miles).
And... While I surely appreciate the expertise and input -
From my fellow FOG woodworkers - The more the better from actual users -
Being that the Section is named "Ask Festool" -
I was (still am) hoping to hear from FESTOOL.
Tyler C.??  Shane??  HELLO??
None-the-less - Thx again, Tom.
Regards, Joe

Modify:  [member=57769]TylerC[/member] [member=101]Festool USA[/member]  - Peter Halle, Moderator

 

[tjbnwi]

Joe,

I live in northwest Indiana. Was out there doing a job, otherwise we could give the unit a try at your location. I know a lot of people in Colorado Springs, none with a Vac Sys.

Tom

 

[pettyconstruction]

Buy it and try it.
You have 30 days to return it.

Btw I bet you feel like super man at the coast lol
Charlie

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