[tjd10684]

I have been making some grip pannels for paintball markers lately out of 1/8" acrylic. I have been using 3M double sided attachment tape to hold the sheet i am cutting to another "sacrificial" plate (1/4" PVC) It works well. the problem is once the parts are done and popped off the PVC I have to remove the tape from the PVC and its just a b**** I have tried soaking in WD-40 and a paint scraper it works but its hard going. So my question to everyone is their some other method of holding these thin plates that would be easier. Maybe a specific brand of tape some kind of temporary glue or something like that. I have looked into vacuum plates but I dont run enough of them to really justify all the support equipment.

[txcncman]

Make an overpress fixture? Clamp from one side, mill 1/2. Move clamps, mill other 1/2? Build you own vacuum clamp?

[tjd10684]

the over clamp may work but its going to hurt my cycle time pretty bad as it stands right now it only takes 15 min to make 8 sets. I have considered the DIY vac clamp but I still have to buy a pump thats the part i cant justify the price of (unless someone knows a place i can get one for less than 100)

Would something like hot glue work? Or maybe rather than PVC sacrificial board maybe I should use HDPE since things have less of a tendency to stick well to that. I want things to stick but not AS well as they do now.

Oh one last thing I forgot to mention is the plate of stock I am using is 12x12

[tjd10684]

Maybe just wood glue?

[fizzissist]

Wax that melts at a lower temp than the acrylic...

[txcncman]

For what you are doing, if you build your fixturing right, a shop vac would probably hold.

Alternative is get a cheap air compressor and connect to the inlet side. Be sure to use some kind of filter.

[dblox]

If you already have an air compressor you can use a venturi vacuum instead of a vacuum pump. They work very well if you have a good seal, I use stand alone venturi units for custom milling fixtures and I have this V-Clamp, Vacuum clamps powered by compressed air. for whatever will fit on it.
I think the V-clamp cost me about $100 NZD, the stand alone venturi units were about $20 each from my local air fittings supplier (SMC).

[kevin swan]

how about blue painters tape on the acrylic then the 3m tape that might work

[txcncman]

Use your finger?

[tjd10684]

how about blue painters tape on the acrylic then the 3m tape that might work

actually its the pvc that I am having the problem with (acrylic has protective paper on it from the factory) but I get what your saying might give that a try. thanks



@fizzissist

your suggestion looks to be the next most feasible if I cant get the painters tape trick to work right wax will be plan B

Thanks to everyone else also any more ideas keep em' coming I really appreciate your help.

[Dennis Rech]

I have been making some grip pannels for paintball markers lately out of 1/8" acrylic. I have been using 3M double sided attachment tape to hold the sheet i am cutting to another "sacrificial" plate (1/4" PVC) It works well. the problem is once the parts are done and popped off the PVC I have to remove the tape from the PVC and its just a b**** I have tried soaking in WD-40 and a paint scraper it works but its hard going. So my question to everyone is their some other method of holding these thin plates that would be easier. Maybe a specific brand of tape some kind of temporary glue or something like that. I have looked into vacuum plates but I dont run enough of them to really justify all the support equipment.

On all of my plastic parts, I find that the easiest method is to just use a mdf spoil board, mill a shallow pocket into the mdf the shape of the material and hot glue the material in place. With 1/8" acrylic, you will just need a dab in the corners and a little dab on the bottom of the paper protecting the acrylic. Use a down cut router bit.
When the part is cut out, push a knife blade under the corner of the acrylic and the part will pop right off.
Peel the paper off the bottom of the acrylic and the hot glue comes off with the paper.

[dak1]

If you already have an air compressor you can use a venturi vacuum instead of a vacuum pump. They work very well if you have a good seal, I use stand alone venturi units for custom milling fixtures and I have this V-Clamp, Vacuum clamps powered by compressed air. for whatever will fit on it.
I think the V-clamp cost me about $100 NZD, the stand alone venturi units were about $20 each from my local air fittings supplier (SMC).

Dblox,
How much clamping force does the V-clamps provide?? I work wih metal cutting equipment rather than wood. Do you think this would be something worth trying or not? I'm guessing they would not suffice. We also do assembly work & if I can find an app where this might help there, I'd just order a kit & play with it.

Dave

[aarggh]

For quick and dirty stuff I find the double-sided sisalation tape fantastic for holding almost anything fiddly down, and despite sticking like mad and not allowing ANY movement, it's very easy to remove without leaving any, or barely any residue. Any residue is simply rubbed off with a cloth and some metho. I buy it from the roofing suppliers for around $25 per 50M roll, and it lasts ages.

I use it for aluminium, wood and plastics.

cheers,
Ian

[mikemill]

The answer to your problem is tabs, what CAM are you using? It probably has a tab app, if not just add a few lines of code to get the tool to HOP thus creating a bridge or tab to your part is held to the parent material see pic
Good Luck
Mike