Attaching mdf board to qcw frame from top

Attaching mdf to qcw frame from top.

I guess I messed up guys. I assembled the qcw frame and mounted the cnc rails and all.

I’m trying to determine what hardware to use. I was thinking about gluing bolts underneath the frame then ratchet the nuts from above.
I’m pretty weak from Heart by-pass. I was going to lift one end and place stands.
Any ideals? : )

Thank you in advance.

I just thought about it. I have the cnc mounted to a kreg bench. I’m just going to run 3 or 3 1/2 inch bolts through the kreg bench top. I don’t know why I didn’t think of that earlier

Hey Scott,

glue bolts? The QCW Frame “Secure from above” has swage nuts. Are you sure that you have the “secure from above” version?

17-SwageNuts
Image 1: A pair of swage nuts
(-- Source: Douglas W. Jones, CC0, via Wikimedia Commons)

Don’t you fear that if you attach a wasteboard on top of a QCW frame with bolts through a table top underneath of it, that you will totally bend it downwards?

Also didn’t you use the Any Surface Leveling Feet to put the QCW Frame on the table? I find to be able to adjust coplanarity of the machine anytime is a great advantage.

Thanks big guy! I had ordered pem nuts but left them in the shopping cart. I have some friends in Houston that have Sheet metal fab shops in Houston. I was going to stop by and pick up a a supply. I was going to install them with duck bill crescent . They have portable install tooling. I didn’t want to borrow equipment. That frame is 6061 aluminum I’m pretty sure. If I had thought about it I would had taken the frame kit and installed the pem nuts.
I didnt use the adjustable feet that came with the kit. In my mind I was thinking the surfacing bit would make everything ok. I had put the feet aside and forgot about them. “Old people” : )
I don’t think I have it in me to take everything back apart.
Thank you for all you information.
Do you think I should break everything down? And start over? I’m pretty disgusted with myself right now for doing so many things wrong.

I had watched the clip and didn’t think I needed the adjustable pads.

Hey Scott,

That is a frequent, but wrong assumption. Be sure that before you flatten your wasteboard, that your machine is checked for rectangularity and coplanarity, because if it is twisted or a parallelogram, flattening the worksurface will not help.

If you surface the wasteboard on a twisted machine, the result will be a still twisted wasteboard, and the machine will only produce twisted workpieces as result.

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I jogged the spindle to about 10 locations all over. I took a measurement from chuck to frame. Most of the locations are the same or were plus .005 to .010. from measurement taken. I did have a spot where it was .010 to .015 off. I took time put the frame together. My diagonal looks like it’s with 1/32 of each other.

Hey Scott,

But you say nothing about a check of twist of the machine. Twist is when one foot of the machine is not in one plane with the three others. A table with three legs can never wobble, because three points in space are always in one plane (=coplanar). The problem arises when your table has four feet or your gantry-type cnc machine has four feet. That’s what the Any Surface Leveling Feet are made for: Put the fourth foot in the same plane than the three others (=ensuring coplanarity).

If you measure the evenness of the wasteboard, or if you measure the distance from chuck to frame, this tells you nothing about whether the machine is twisted. You can simply not detect it with these methods. Methods that work are described in the link above, e.g. the two fishing lines method.

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Thanks again for all the input. I have never had a twist problem on a CNC bed or rails. I have use all kinds of CNC beds and rail systems. Only shimming situations. And that’s a given on old CNCs. I’m a retired precision sheet metal combo machinist.
I have had a wild work career . restoring B-17s to working in the model shop at NASA back in 98 working on the Space Station. It’s amazing how much an old brain can forget after retiring. I got a feeling everything is going to be ok.
Again, thank you my friend.

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Hey Scott,

you have the machine on a Kreg table and say you don’t believe in twist? Good joke :slight_smile:. Do you use a granite reference block as workshop floor? :wink: A Kreg table is not stiff enough to avoid that on its top, it will have the amount of twist that the workshop floor has where the table stands (at the moment, and will change when you move the table, which will require to readjust the twist. Thats’s why adjusting the twist (=coplanarity) is made so easy with the Any Surface Leveling Feet: Many people have their table on casters, so they can readjust the coplanarity after each table moving.)

But is this only because you never checked for twist?

What is a shimming situation? Is it removing twist of the machine? People that don’t have the Any Surface Leveling Feet often use shims to adjust coplanarity. Another solution is height adjustable casters on the table but this is more for people who have fun bending down often

I understand that at the moment the overall situation you describe is frustrating. But I can only share some knowledge. Especially when you say you don’t have it in you to take everything back apart, I think it is very frustrating, of course.

Your question whether I think you should break everything down and start over, depends on which kind of person you are. It could be that if you check twist with the two fishing lines method and you find out that all the kitchen cutting boards you make will wobble, then you will remain somewhat unsatisfied until you made everything on the machine perfect – as long as your health permits (I wish you the best in this respect). But it could also be that you make only signs and flags and an amount of twist doesn’t bother you. I don’t know you, but you will know, or find out in the near future.

Good luck!

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I do enjoy bending down! But had not thought of this as a way to indulge my bending hobbby!! :rofl: