So I was trying to tram the head of my machine after building a workbench for it. As I leaned in and placed my hand on the work table I noticed my indicator move maybe.005 to .010. I started to investigate and noticed the countersunk screws under the spoil board are crowd and not flush causing the spoil board to bow and flex. I also noticed the aluminum cross members flexing as well.
I’m thinking I might add some holes and screws to pull the crossmembers down to the workbench. don’t worry I will face the work table after.
Anyone else come across these problems? And if you haven’t double check your machine. 0.01 might not seem like much but it’s enough to effect surface finishes on harder materials.
Having the bolts firm is important. Not much you can do about the aluminum flex. Previous posts suggested getting high-density foam to support under the table. I got Fatigue Foam mats from Harbor Freight to help quiet things down and take up any imperfections in the table
Im not a fan of pulling the cross members down to the table. If there is a bow in the mating surface and you get the two surfaces to meat that bow can be transferred to something else either another component of the machine or the table surface.
I would do the following
Check to see if the table surface is flat first if it is great. If not you should deal with that first.
Then get a countersink bit and re-seat the pocket for the screws and get them down slightly below the surface of the cross members.
with all the spoil boards off check the cross members for gaps at the table top and shim as needed. this should correct your problem.
The weight of you leaning on the table is not as much as material sitting on the spoil board. If your table is made of Wood/plywood even the changes in temp and humidity will cause some changes in whatever you try to measure.
If you correct the main problem (cross members Bolts) and surface your machine you should be good to go with that.
I’ve been debating about doing this, as i can push down on my spoilboard and push it down. I’ve surfaced my spoilboard many times so it’s tram to the spindle until it flexes under the weight of a big piece.
One of these days i need to look into why it’s bowed and see if i can address it.
It’s usually the weight of the piece not cutting or anything. Throw a 4x8 sheet on there and it’ll flex down. or a heavy piece of walnut in the center.
