Holding Thin Workpieces: Vacuum, Superglue, and More!

[@prodesign8189]

I did a 3 x 5mm ss eye wear peice for a company I am currently working for with a .032" mill using locktite adhesive and blue tape and won thier trust when I showed them I could do it. (didn't think I could but tried and won). Talking about cutting into .032" ss sheet and coming out with a peice so small you need tweezers to hold. Any how, I use the tape n glue for many clients and I love it. Thank you John. Hope you all are well and Jarod and family too. I'll stop by for a class soon. If you haven't been to a Saunder's training class you are missing out on moving forward in becoming a small shop business that can make your life more meaningful quick!

[@ImranImran-wi5dh]

So very interesting, I have worked in AERSOPACE parts manufacturing and we used to machine the entire wing skin beginning with 35 mm thickness of a full 4ft by 8ft sheet and finishing up with thicknesses as low as 3.5 mm. All done using vacuum and high speed machining. Also hybrid fixtures with both mechanical clamping and vacuum for complex fuselage frames with multiple pockets. A word of advice ... The vacuum system must be integrated with the machine PLC so in case of vacuum loss the machine does an automatic emergency stop.

[@ImranImran-wi5dh]

It would be useful if you share the method to calculate the cutting load ao that the required vacuum pressure can be calulated.

[@OldCarsAreFun]

This is great, thin parts can be challenging

[@Mike-ke7ud]

John, the green tape with the 2p-10 adhesive and activator are my go-to combo, I have been very successful with combo (much better than the blue painters' tape becomes brittle hard to get good even bonding (high spots that harden fast when using activator) and tough removal) as always make sure you have a solid decked surface to start with, the green tape with the 2p-10 is easily remove no mess and the part unless you get a bit of a gap in the tape o the part side. I have done all flat plate work this way and i am always amazed what you can actually pull off with just a bit of foresight as to when to break thru on multiple up parts with a drill or milled hole. Endless. I have a vacuum plate have been saving the surface for bigger runs but look forward to the sandpaper trick this has been a gem from you that just keeps on giving. especially fun to wear SMW teeshirts when showing off the greatness. sometimes trying not to take the big cut pays off in dividends especially if you don't use the activation I find pockets of goo that still had air around the adhesive look for slight rotation motion as something might be about to let loose. this is a fun subject thank you for getting me in the right direction back in the blue painters' tape time frame...the golden nuggets! Thanks, John as always look forward to more.

[@philliplipscomb9461]

I've used double sided duct tape on several parts in the past on my machine or cnc router.....several occasions I've used double sided cellophane tape when cutting small plastic and aluminum sheet,,,,I like the idea of sandpaper between the part and fixture,,we use folded up pieces of sandpaper between the tie down clamps on uneven surfaces when holding down weldments the size of small houses at work p.s we made it home just fine with that drum in that honda fit thanks

[@andrewbeaton3302]

Yes thank you for this video! I needed this today!

[@sportbob06]

Datron is a small Cnc router trying to be a mill. Nice machine, but the vacuum mentioned was pioneered by industrial router manufacturers (with the help of Boeing) 30 years ago and is known as high flow vacuum. It was first used with balsa wood end grain boards and high CFM pumps. The industry has since went to ldf table and mdf waste boards. The pumps used are massive (15-25 HP, 300+ CFM) because table sizes are typically 10'x5' or larger.

[@yo64yo]

we have 2 at my work's machine shop, with the mdf board and they are probably 15'x6' or around that. we usually duct tape the aluminum or lexan down around the edges. I haven't actually ran it yet and I am curious how it can cut 50 parts out and keep vaccum with no downtime inbetween to tape up the sections it exposed. we leave tabs on each part as obviously they would go flying, i'm just not sure of the toolpathing for the last bit. small axial cut's until there's a few thou of material left and then what?

[@sportbob06]

@@yo64yo there are a lot of fine details you must pay attention to when using high flow. First, make sure your table has been flycut and is clean of dust and debris. Also make sure the material is not warped or twisted or has any burrs that will keep it from pulling vacuum. If you can pull 15+ inches of hg during your cuts id say you have a good chance of being successful. For small challenging parts you can do exactly what you mentioned, cut everything down and leave a few thou skin. Then machine the skin away at a slower feed. Your starts and stops should be in such a way that majority of the skin is attached to the rest of the nest until it's just about cut free.

[@MakeTechPtyLtd]

@@sportbob06 are you talking about centrifugal impeller pumps, piston or venturi?

[@sportbob06]

@@MakeTechPtyLtd rotary vane. Both dry vane and oil ring.

[@MakeTechPtyLtd]

@@sportbob06 oh cool. I hadn't looked into that before. Very interesting. Thanks!

[@danielabbey7726]

Thanks for an excellent video, John!

[@Mrgnothing1]

Double sided tape is good, as long as you have a way of getting the part off as it is so sticky that parts get stuck and can be very difficult to get off

[@INeALiS]

Dude you are a Saint. This series is beyond helpful 👏

[@owievisie]

I don't know how much vacuum pressure we have but our shop build vacuum table is 100x50 inches :P We need to make a smaller one for smaller parts

[@CncWoodProjects]

Tnx for you video i learn a lot, today i made my first "serious" try with aluminum cutting in my cnc (i normally make 3D carvings in wood) but now finally arrived my new 24k rpm 1.8KW ATC spindle and i need to make the new support for change the spindle (actual spindle is 18k rpm 1,1kw). If you want to see it and make some fun of my fusion 360 strategies see in my little channel (OMG i made one big mistake and the job take to many time for finish, ramps and me...). Another time thanks for your videos i learn a lot.

[@MechanicalCore]

I generally use 502 glue to fix the parts, which is convenient and fast, but it's troublesome to remove them

[@mikiauto73]

Do you guys have experience on holding and milling complex wood parts?

[@banjohero8352]

Try 2 sided Carpet tape its crazy strong! I tried it about a week ago and was amazed at how much it can hold kinda tough clean up.

[@myersmadeindustries]

Try a sandwich of the green Mylar powder coat tape with double sided linoleum tape in the middle. Holds great. leaves no residue on parts/sub plate. Uniform thickness of the tape sandwich is around 0.010". Handles coolant very well.

[@paulbelgradostringedinstru715]

Thank you , great 👍👍👍

[@DrMatt96]

i mess with your videos my guy, no cap

[@prodesign8189]

Wow, after watching further I realized you machined ceramic. I tried and it would blow thru in the bottom. Wasted some very expensive ceramic plates trying to machine that stuff. It is a material we need in RF design to allow heat transfer without conducting high power thru the junction and I failed on that. Ceramics is crazy.

[@saudfaisal2452]

Can we use it on stainless sheet

[@dominic6634]

Once had a boss refuse to make a vacuum plate or use glue. So we spent 8 hrs dialing in this part with clamps. Eventually left that place.

[@Sketch1994]

I really don't want to remove 2 sided tape from 250 parts per week...

[@CuongTran-yv9ir]

👍👍👍

[@MakerMike-bx5ms]

Where is Johnny 5? I want Johnny 5!!!

[@MakeTechPtyLtd]

[Edited] A perfect vacuum is 14.7psi . In my experience the venturi vacuum generators pull about 5PSI. Anyone else measured the vacuum on a venturi vacuum generator? Edit: Actually today I found I was able to get 14+psi from a venturi vaccum generator.

[@russellmiller2564]

You likely aren’t putting enough cfm of air through it. Check your Venturi specs. More volume, more vac.

[@MakeTechPtyLtd]

@@russellmiller2564 There's some good documentation at www.blowervacuumbestpractices.com/system-assessments/vacuum-generation/utilizing-venturi-vacuum-generators-efficiently

[@MakeTechPtyLtd]

@@russellmiller2564 I agree that more cfm creates more vac, however the drop off in diminishing returns is very significant. From link above: "The increase in the level of vacuum from 18" to 27" Hg is 10 times more. " (in psi 8.8 to 13.3) My 5psi figure was recorded on an industrial machine getting heaps of air but it was old and may have had some tiny leaks. In any case, the vac gen and work holding I installed on the machine had many times more holding force than required.

[@MakeTechPtyLtd]

@@russellmiller2564 thanks. Original comment edited. Today I got 14+psi on a different vac gen and machine.

[@russellmiller2564]

@@MakeTechPtyLtd Glad you got to the bottom of it