Roots model 33 vacuum chucking blower

[Chuck Keysor]

Hello, when I bought my used PRT Alpha 5' x 12' almost 3 years ago, it came with a Roots Model 33 Vacuum Blower/(pump?). I have done nothing with it, deciding it was more important to learn about the other aspects of programming and running my machine. But I am getting really tired of nailing all my little wooden plaques onto my spoil board.

I have ZERO background in this type of equipment, so upon reading the manual, most of it makes no sense to me. The manual refers to many different models, and for example, it references checking the sight glass to monitor the oil level. But there are no diagrams showing where the sight glass is, and I don't see anything that looks like a sight glass.

The manual says the unit must be mounted on a flat surface, and says a machinists level should be used. But the people I bought my PRT alpha and the vacuum pump from, had the vacuum blower sitting on a crooked skid under the PRT alpha. So, I built a heavy duty roll around cart for this BEAST, assuming it was better then what the previous owner had done. I had to build a cart just to be able to move it into position.

The manual says if the unit has been sitting, check the cylinder for rust prior to start up.

So for starters,

How do I check for my oil level?
How do I check that there isn't rust in the cylinder?
Is my mounting of the unit on rubber wheels a stupid mistake that only a rube would have done?
How do I bring this on line without messing it up?

Any advice will be appreciated. Hopefully this isn't such a broad request, that it is impossible to get good replies. I am pinching every penny, so I don't want to call in an expert Roots service technician.

Thanks to anyone who can provide me with some direction. Chuck

[donek]

if you google your subject, the top 3 listings are companies that re-manufacture these things. If you call them, they can most likely answer all your questions and be willing to sell you any parts necessary to get your system running. If they won't work, then they'll likely offer a trade in price for a replacement.

[SterlingDevelop]

Chuck,

We have the same blower, bought it used as you did, and we have gone through several modifications of the system. Feel free to call, I'm sure we can help.

Brent
www.dcscnc.com (http://www.dcscnc.com)

[bleeth]

Chuck:
Direct answer to your question-That thing is a workhorse and is not nearly as touchy as the manual may make it sound. Pipe your vacuum system, plug it in, and enjoy!
Some models have a sight glass and some don't. Call SB, who markets them with their tools, or post more specific info for more specific answers.
Also, take off the wheels and put it on the ground.
Remember that having bought a used SB you are going to get the same friendly customer service from SB as someone who bought a new tool direct.

[Chuck Keysor]

Hello Brenton. I will call you later today. Thank you for your helpfulness.

Hell Dave. Thanks, I did not realize that the Roots Blower was a Shopbot supported device, though I had noted it was painted Shopbot blue! So I had not even imagined I could call SB on this. Thanks for that VALUABLE information!

Thanks again, Chuck

[Chuck Keysor]

Hello Brenton. I have tried phoning, and with my calling card, I get a message saying there is a problem with the number. I left a private message. But can you email me and let me know the best phone number and when I should call to best fit your schedule? My email is chuck.keysor@sbcglobal.net

Thanks, Chuck

[Chuck Keysor]

OK, based upon two conversations with owners of blowers, and the fact that I have no place to put my Roots blower except under or near my Shopbot, (my shop is in the basement of my house) and all the noise the Roots blower creates when it runs, I plan to not use this. I should probably sell this.

While I am not asking for advice at this time, I did want to post the conclusion of my query, and thank those of you who have given me your time and opinions. Thanks, Chuck

[Brady Watson]

...and all the noise the Roots blower creates when it runs, I plan to not use this. I should probably sell this.


Good choice, Chuck. Those roots blowers are very high performance. They move a LOT of air and pull about 14" Hg if my memory serves me right. The problem is they are loud...like 92 decibels loud, and if you are married, it would be a one way ticket to lonely town if you fire that thing up for any period of time!

When a customer ordered one of these, SB recommended that the pump be located outside in a mechanical room or other protected enclosure for noise abatement. This pump will literally rattle your skull, and heavily ripple the surface of the drink you are holding in your hand.

I would flip it & get a regen...or a Becker if you want to pull the stars closer to the earth... :D

-B

[Chuck Keysor]

Well, here it is, 7 years later,,,,,,,,, and my Roots blower is still sitting under my Bot.......... I am going to make various upgrades to my Bot this winter, and I'd rather have a smaller vacuum when I make my other upgrades. I only want a vacuum to hold down large sheets of MDF and I don't want all the noise with the Roots blower.

What is this worth? I found two ads where they wanted $2000 for a Roots blower. But I have no idea if they were able to sell at that price. What is a fair asking price?

I do drive between Chicago area and St. Paul to visit my sister and her family, and could consider delivery along that path. Otherwise someone would need to come and get it.

Your advise will be appreciated! Thank you, Chuck

[Brady Watson]

Chuck,
There's really no set price window for used pumps. When I bought my Becker ($10k new), I paid like $1500 for it (used from Boeing...so it was maintained well) but it cost me like $1200 to get it shipped from WA state to me. It's worth whatever someone in your neck of the woods will give you for it. There's next to nothing in my area and low demand. If you live in a 'machine desert' like me, you might get more for it, but you'll have to wait a bit longer to sell it...vice versa if you're in a spot where people actually work with their hands for a living.

Regarding the pump itself, IIRC, the 15hp version was a really good bang for the buck @ I think around $6k. It would pull 14Hg" and do an amazing 600CFM. However, as you probably know, roots blowers will LITERALLY rattle the fillings out of your skull meat and hearing protection is absolutely required. I recall installing several of them where the customer did not heed SB's recommendation to house the unit in a sound insulated mechanical room (aka outside) - only to have me unhook it and send it back for a quieter, but more expensive pump. "It's got performance you can feel" should have been the slogan because when it is running, it's like your whole body is being thumped - and whatever liquid/drink you have in your hand dances with concentric ripples. There may be weight loss benefits to hanging out while it's running ;)

So I guess the real question you should ask yourself is if it would be worth isolating the pump - either outside or in a purpose-built box with the unit sitting on rubber/cork pads. Customers have done this, with the caveat that you still need cooling to the unit, which some have done using labyrinth shaped vent runs and a few small inline fans. It's not quite as complicated as it may sound, but it is certainly worth looking into. The reason I'd consider it is because pumps are kind of a hard sell and I doubt you are going to get anything that will approach the performance of what you already have - especially on a big 5x12 table where CFM is important. Big commercial machines use multiple Beckers (2 to 6 of them) to get the CFM numbers up. I would personally at least try to quiet it down by adding another/longer muffler and making a shroud/box with provisions for cooling. You've got the CNC...so you can make the box with CNC type joinery and get the baffles/ports/labyrinth 'seals' perfect the first go around if you design it right.

You may find some of the ideas on these pages helpful:

https://www.enoisecontrol.com/vacuum-pump-sound-reduction/

https://allnoisecontrol.com/product/how-to-soundproof-a-pump/

Edit: Dresser Model 33 does 195 CFM. I don't recall if this is a 5hp or 7.5hp model. It's rated @ 12Hg"; Max 15Hg"

Also...run it to warm up the pump and change the oil...I wouldn't be surprised if that old oil came out like water.

[Chuck Keysor]

Thank you Brady! I always greatly appreciate your input. It would make more sense to put it in a sound isolating arrangement of some sort........ Unfortunately, this is in my basement, right under the kitchen, and I live in town with small city lots, and no place to put this beast...... But before I post this in the for sale listings, I'll read the articles you provided........... but it is late now,,,,,,,,, Thank you again! Chuck