Black Box Vac Source

Thanks Gary,
Funny my manifold under the table looks just like that. I left room so I could cut the 2 " pipes when I built it so I could add that type valves later but I haven't yet.

I am going to save your post so I can refer back to it. I was thinking of adding a 3rd motor to the 2 I have now. I may not need it but with your setup they only run when the vacuum drops I really like that idea. I should gain a lot when I redo it and glue the spoil board and seal the edges. My spoilboard edges are semi sealed now I varnished them when I made the system.
Mike

Hey gaRy does that box come in white:D: Also I did remember the R












r









r

Thank Gary. I miss post # 8 That help alot. Couple of guess those. Was their any thought in useing the black over the white or is that what you had? The other question. Where did you place the vac switch in your system? I can't seem to see it in the picture. One more. How far do you think I can place the vac unit from the table before I start to lose vac? I want to place it about 20' from my table and thinking of used a 4" trunk line. think that would help?

thank
frank

Frank...
Black was just the right height on the rack to slide onto the cart and the white had to be lifted. No real reason, as they are the same product. Black box sounds better.

When I installed the analog swith from Joe WW I drillead and tapped a 1/8" pipe thread into the front vac chamber on the side with the relays. Once I switched to the digital I tapped the Vac distribution manifold under the table.

With 4" pipe, I dont think that 20-30 feet would be a problem. Look at post #40 for a little more info

by holding Gary's old saw hostage, i got him to come back to the keys and help me with the vac box on his old machine,needless to say it is awsome.Being warm and sunny in s fla.we ran the vac motor box outside now the shop is so quite. Gary just what to say again a big thank you for all your help and knowlege:cool:

Hi Gary….
I just wanted to thank you for the picture of the new vacuum box you built and design. Also thank you for the help you gave me with it. I try making it out of the melamine like you. But I can’t work with that stuff. I made mine out of ¾” birch veneer. I got to tell you it works GREAT. The sound is way down. I think I will just keep it in the shop. The vacuum I can’t get over. I got my vacuum switch in today I can’t wait to install it.

Again Thank
Frank

Frank...
Glad its working out for you. I agree on the melamine.

One thing to look out for is relay switching current. Many of the digital switches only have 80ma switching current. Make sure yours is below that.

thank gary I will check in that. forgot to show you finish box[ATTACH]Attachment 11778[/ATTACH]

Frank...

That looks good! Thanks for posting.

I just made my two vac box. but i did it out of plywood as it was all I had. I did not use all of the baffles though I wish I had the room to do it. it is more noisy then the feins. they are about 80db and the box is 90db. but I also have twice the vac inches. I will need to hard hose it though the fein hoses want to collapse.

Hi Gary I had a question. Did you put a filter in between your vac table and the black or did you just pipe it stright thru so the dust go thru the vac motor? BY the way It really work great. I still have a hard time beliving how good it work.

Frank...
No filter installed. Glad its working out for you.

Guys...
A few notes on this system. Now that I have built, sold and installed a number of these systems, Most are being switched to full manual control.

Reasons are:
1) cost (saves a few hundred $)
2) I have noticed on mine that the vacuum varies much more than I originally thought. From a freshly surfaced spoilboard to 25 sheets into a job I may have almost 2 inHg difference. This moving target of initial vacuum made the hysteresis settings a real pain. In the end, sheets were initially cut with 2 motors and 4 are used to add hold down for the cut thru.

I was hoping to automate this switching, but it appears that either another approach to the control or full manual is the answer.

Greetings, Gary

Thank you for this post and for the knowledge that you have shared on this forum. I have gleaned much from you (and all who have contributed).

It has been about eight months since your update and I am wondering if you have any more updated information on how your system is working.

I have been using two Feins on four valved zones for the past several years, but one of them has now melted all of the internal plastic parts for the second time. Rather than the cost of another repair and another failure, I have ordered two LH 6765-13 vacuum motors from Ward and I am preparing to build a two motor box similar to yours with manual switches.

I have read every post that I can find regarding vacuum boxes and have seen two schools of thought regarding filtration on the intake side of the vacuum system. Are you and the others that you have built for still running without intake filtration?

Kind regards,

JIM

Jim, I built Gary's vac box and put 4 motors in it. They are divided into two chambers inside the box. Each chamber has two motors. Two motors are used to hold 90% of what I cut. The additional two motors can be turned on to increase the CFM to more securely hold the parts when necessary.

I've opted to run mine without input filtration. I have set mine up where I have a simple little desk fan to blow clean fresh air in to the intake part of the box so the motors are always getting clean fresh air. I check the motors regularly to see if there is any dust or debris build up and so far, after about 4 months of running daily, I've had no problems.

Gary did a fantastic job on the design for this box. It works great and my hold down capabilities on my sliding-valve controlled 7-zone table could not be working better. I am extremely pleased with the performance. Even at an altitude of 2500' ASL I still get 7"-8" of vacuum.

Jim...
Along with Don, I have given info to a number of guys that self built, sold a half dozen outright and sold and installed a few more. Other than using a manual switching system instead of the digital switch and relays, no other changes have been made. No changes have been made (by me) on the box design.

So far, no complaints. Mostly good reviews, similar to those by Don. Even better news: No motor failures that I am aware of. Most of my sales have been to commercial shops.

Since 4 of these motors (I used the 240V LH-7123) cost less than a new Fein, consider the advantages of over 400cfm. The 240 V versions use half the amps, have more power and generate less heat. Vacuum is like money; you can never have too much.

I am sure that is not impossible to pick up some debris, but if care is taken to clean the tubing and a fully adhered spoilboard is used, very few that I have seen use a filter. That said, no one could argue that it is a good idea.

Greetings, Gary and Don

Thank you for your replies. Gary, I was able to switch my motor order to the 240V LH-7123s. Ward is great to deal with. I am going to build a four motor box with a partition to divide the vacuums into two sets like Don did (no check valve). For now, I will just use two motors as they will provide much more vacuum than I have been using for the past years. When I can afford it and have the time to add another circuit I will add two more motors.

Would ether of you be willing to share or sell your box plans? I understand the pictures that are posted, but I would like some dimensions as your boxes seem to work quite well.

Kind regards,

JIM

Jim...
My plans, which I sent to Don were designed in eCabs and processed as a TWD file thru the SB Link. I havent taken the time to convert them to DXF or PWks files.

Jim,

I have the check valve in my vac box with two motors in each chamber. 90% of the time I use only two of the motors. I normally switch on the 2nd set of motors (which opens the check valve) when I go to cut through smaller parts. It sticks them to the table like glue.

As Gary said, he sent me the plans from eCabs and I cut the parts through the ShopBot Link. The only thing I can think of would be for you to sign up for eCabinets (it's free), download it, bring in Gary's files, then use them to create the Partworks/Aspire files from the dimensions.

Gary and Don,

Thank you. Don, PM sent.

Kind regards,

JIM

Quote:

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Originally Posted by dlcw

Jim,

I have the check valve in my vac box with two motors in each chamber. 90% of the time I use only two of the motors. I normally switch on the 2nd set of motors (which opens the check valve) when I go to cut through smaller parts. It sticks them to the table like glue.

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I am glad to hear that you get by with 2 motors most of the time. I plan to try to nest smaller parts within 24x48 zones, and I am wondering at what point parts become small enough that all 4 motors are required. I am going to start out with the two motors I have.

I don't mind cutting drawer parts on the table saw if I have to. As long as I can hold nested parts larger than 1-2 square feet I will be happy.

Michael...
I dont know if this is the best barometer, but I was able to cut a half sheet melamine of 3.5 x 8 dadoed stretchers without losing any. Only the onionskin pass has the 2nd pair of motors on.

Quote:

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Originally Posted by michael_schwartz

I am glad to hear that you get by with 2 motors most of the time. I plan to try to nest smaller parts within 24x48 zones, and I am wondering at what point parts become small enough that all 4 motors are required. I am going to start out with the two motors I have.

I don't mind cutting drawer parts on the table saw if I have to. As long as I can hold nested parts larger than 1-2 square feet I will be happy.

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if you use a smaller downcut bit is not an issue. I use a 5/32 downcut when am cutting smaller parts. the thinner the material the smaller the bit I use when the parts are small. I can cut a sheet full of 3" circles and not loose one.

Sounds good. I am pretty excited.

I am going to work on my plenum, and spoil board later this week. I have acquired all of the plumbing.

I bought a 12x24x24 NEMA type 1 enclosure, along with a pair of louvered vents. I am going to mount my motors inside of this enclosure, and mill some flanges from 1.25" thick type 1 pvc to mount to the outside. I got a pair of pvc swing check valves. I should have the rest of the materials for this on monday.

it's best to have check valves on both sets in case one of the two motors goes out. so you can choose what set you need.
as far as heat it seems the exhaust is hotter from my 220's then my fein type motors.

I cut 4" coasters (about 230 per sheet) out of 1/4" MDF for a local sports plaque maker and with the new vac setup, I've eliminated having to use any tabs. Off the machine into the customers parts bin. Before I setup Gary's vac box, I always had to use tabs which made for a LOT more work. I've been able to lower my price to the plaque shop because my labor has gone down ALOT. He wins and I win.

I try never to use tabs they are suck a pain.

You're right Steve. They are a PITA but sometimes a necessity. Some projects my vac system just won't hold. :(

using smaller downcut bits or the pressure foot keeps me from needing tabs most of the time. though sometimes it will waste extra material.

I use the hold down tool on occasion. The only thing I found was that sometimes the chips that are dragged around by the hold down will scratch the surface of my material. I've had this happen a couple of times as the dust collector hood can't be on at the same time as the hold down.

i'm using two of Gary's original 220V motors mounted to a simple "temporary" plywood box manifold which is connected to my PVC plumbing system (ever since my last Fein gave up). I have the other two motors on the shelf but haven't had time to set up the fancy new four-motor manifold so they are just sitting there as backups right now.

I cut full sheets of melamine and plywood with few problems as long as I take a few steps, like ensuring that no small parts near the edges of the sheet get cut last. I keep small parts away from the edges, make sure the small parts get cut first when there are a mix of small and large parts on the sheet, and try to separate small parts to leave a web of waste around them when necessary.

I also use the two motors to cut solid wood parts down to just a few inches square on a single 24 x 24 zone by nesting them against an "L" shaped fence which is butted to the table stops, covering the rest of the zone with 1/4" one-sided MDF (or anything non-porous), and taping all the seams with blue masking tape. Rigid masking boards work better than plastic sheet to cover the rest of the zone because they provide great resistance to sideways movement of the workpiece. Taping it all together (with the vacuum running) makes the whole thing act as a single workpiece, giving you effectively the surface area of the whole zone to prevent sideways movement.

Using a down-cut bit leaves enough chips packed in the kerf to keep most wood parts from moving or losing too much vacuum, plus it applies downward pressure as it cuts. I can count the number of times I've had to use tabs in the last five years on one hand.

Quote:

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Originally Posted by beacon14

i'm using two of Gary's original 220V motors mounted to a simple "temporary" plywood box manifold which is connected to my PVC plumbing system (ever since my last Fein gave up).

I can count the number of times I've had to use tabs in the last five years on one hand.

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This is really good to hear.

Quote:

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Originally Posted by beacon14

I also use the two motors to cut solid wood parts down to just a few inches square on a single 24 x 24 zone by nesting them against an "L" shaped fence which is butted to the table stops, covering the rest of the zone with 1/4" one-sided MDF (or anything non-porous), and taping all the seams with blue masking tape..

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Thanks. Based on this recommendation, I am going with a 5 zone plenum, rather than 4. I am glad that for whatever reason I bought an extra knife valve. I will add a 24x24 zone.

Glad to be able to help. Sounds like a good plan.

Hello everybody. My name is Daren & I'm posting this - my very first post - from my home in western Canada.

First of all, let me say thank you very much to Brady, Gary, David & many others for all the fabulous info you have shared with the rest of us clawing our way up the learning curve. I really admire your commitment to sharing your wisdom, as well as your creativeness & workmanship. I have learned more than just SB stuff from you guys here.

About me. I've had a used, dual-Z, 4x8, PRTalpha for a couple of years, but until recently I haven't been able to spend any real 'quality' time with her. After reading (and re-reading) through this forum for many months (I'm a slow learner) I have started working on my first (and very much desired) vacuum table. I always planned on posting something on the forum someday, it's just that until recently I didn't feel like I understood enough SB terminology to say anything relevant. A few weeks ago I was further inspired by the sense of helpfulness you guys provide in a short Q & A phone call to David about his table design. Now that I've broken the ice here, I hope to be able to do the same as you some day.

I currently have two, 240V, LH7123 vac motors that I'd like to build into a black box like Gary's. I'm not sure yet whether to build the box big enough to possibly expand it up to four motors later, and if I should include a series/parallel valve. I plan on cutting sheet goods in various sizes as well as solid wood parts & I'd appreciate your feedback.

My questions for Gary are:
1) Would you share (or sell me) your black vac box design? I have recently installed eCabs & the SB link trial version, but I have not purchased it. It looks good, but I'm waiting to get more fluent with the SB & eCabs before I invest any more money. I would however gladly accept it from you in eCabs file format (and decipher it from there) should you decide to share it with me.

2) I have read your previous vac motor setup (where you had 2 motors setup with a valve that would switch between series & parallel). But I'm not sure about this black box design. It seems to me like you are only running it in parallel mode. Is that correct?

3) I'm not clear how the integrated check valve works. Could you please explain to me how it operates?

Cheers from frosty Edmonton!
PS. A big thank you also goes out to the ShopBot staff & management who welcomed me with free support when I first called them with my question of "how the heck do I get this to connect with my computer?" This is definitely a business worth supporting.

Daren...
Thanks for the kind word on behalf of myself, David and Brady. Answers to your questions:

1) Yes, I have sent it to others. One note: it requires use of both eCabs and PartWorks to complete as the exact motor geometry was unknown at time of design.

2) This box is parallel only. My testing showed very high temps when connected in series.

3) It is simply a pivoted flapper valve made to mimic the check valve provided to our user group by Brady.

I would recommend using the 4 motors as it will allow you to hold most anything (that is reasonable). Getting the CFM over 400 is the single biggest advantage of this system over most others.

Thank you for enlightening me Gary.

I think I'll be able to work with your eCabs design. My goal with your drawing is not so much to use it to cut from, but rather as a guide to show me how you directed the airflow. I assume once I see it I will better understand how the flapper valve works. Will you send it to me via email, or is there something I need to do?

I'm glad to hear you think parallel is the way to go, that helps reduce the complexity a little.

Daren..
Send an email to caseworxmfg (at) gmail (dot) com and I will send you the file(s) when I return to Durham.

There is no referrence to the check valve in the files. There is actually more info in the post via the pictures.

Gary. After looking at your design in eCabs I now understand how the flapper valve separating the two pairs of motors works (doh!). I'm going to build a box like yours (with room for 4 motors) that will allow me to use the 2 motors I have now with a flapper valve & add 2 more later. But I've still got some questions if you're not tired of me yet.

1) I noticed there are a couple of small differences between the eCabs drawing you sent me & the drawing & pics you posted here. I assume the ones you posted here (ie: below) is your revised/preferred design? If so, what is the open cavity used for on the top of the other side? I saw that you used 1 side for the electrical switches.

2) How do you plan to access the motors for service/replacement? Remove an end, then top, then the upper-center fixed shelf above the motors?

3) Do you think it would be beneficial to seal around the vacuum exhaust pipes (through the melamine) with silicone to insure that all of the exhaust is sent out below the box & not coming back into the box? Would it help to keep the motor cooling intake & exhaust air completely separate from the vac exhaust? Perhaps with your open-bottom design this is not important, but I was even thinking that it might be worth adding a vertical, length-wise partition under the middle of the cabinet section to help keep the high-pressure (I assume) vac exhaust from pushing it's way up the lower-pressure (I assume) cooling exhaust.

4) I'm not sure how big of a breaker I need for 4 of theses motors. I believe that they draw up to 6 amps each. So does that mean I should get a 25 amp breaker?

Thanks

Hello all,

I am also building a box right now, very similar to Gary's design, and thank you very much for all of the information on this forum!

I am putting together a 5 zone system, with a couple of tweaks that I'll detail in the thread I've put together for the build.

http://www.talkshopbot.com/forum/showthread.php?t=14940

For now though, I'm having a little confusion about these vacuum motors...

I see in the black box image that the cooling fans point upward... but where is the inlet for the cooling air? It seems from the picture that that part of the box is completely sealed... is it above? And, is that intake filtered? It seems like it would be a good idea, keep the dust off the cooling fan blades. Maybe with a shopvac filter or something to that effect?

Any help is very much appreciated! Thanks for everything already! :)