OK its been 3 months since I last posted about building another router,, I have the linear bearings now to start the build and have been trying to get the best ideas that I can find on the internet..
    I am going to need one more HIWIN linear rail thats 58" long I have 1 rail and 4 bearing that i picked up on ebay and they are like new but the new piece of 20 mm HIWIN rail from a dealer is more than I paid fo 1 rail and 4 bearing so the 58 inch rail will give me approx 48" travel for the Y and I have the linear bearings for the X and Z so the travels will be 48" x 25" with 6" of Z travel ,, Money has been tight so I have just been picking up a few pieces at a time until I get all the parts and design together but now that I have bearings that helps because I know the travels now .. I will be using 2" square tubing for most of the parts of the main frame and 2x6 square tube for the gantry and 1/4 in steel sides for the gantry ..
      One more question about the gantry bearings , I have noticed that some routers have the x axis bearings on the top of the side frame rails and some are on the side of the frame and I have even seen some with the bearings under the table top to keep them cleaner..Which settup would be more stable?I can see the benefit of the top and outside of the rail but which would be more stable? On linear bearings where would the load be better distributed?Also I have seen some people using belts insted of acme or ballscrews what is your opinion on that choice?I have acme screws on the wood router now they work pretty good but the delron nut is where the wear comes into play.. I do like the idea of a double drive on the gantry to keep any binding from coming into play..
     Hope this post wasnt too long but there is soo many items to consider and I am not in anyway an engineer in machine design as you can tell from all of the (some may think simple ) questions but I did learn quite a bit from building the last router from MDF..
       Thanks for the info guys
Gary

Hi Guys:

  Sorry for the long absence form this topic, been awhile since I visited here due to workload.

In answer to the above questions, bearings can be placed in any of the top, side or bottom, no real
advantage structurally I think, but side or bottom is advantagoud bnecause it gets them away from
your material. We didnt do that, we went for Top mount simply because it was easier and worked for us..

 Here's some photos of the table as the rebuild comes down to a close..

Art

OK  back on my build again but actually getting some progress made , I have the Y Z Gantry almost finished just need to attach the router and one bearing support on the bottom of the Z axis backplate,, ANY opinions are welcomed , this is my first metal router , I stripped the wood router and threw it out to make room for the new one.. The X plane is going to be able to cut approx 48 inches..
  And I am welcoming ANY opinions before I get this finished, I did hook the servos up to my control and I am really happy with the results I can jog back and Fourth up and down the hit go to zero and it has been coming back to zero without any noticeable backlash using my micrometer..I know that is not under a load but so far so good..
Gary

Looks excellent. Strong and accurate. Id say just keep going..

Looks to me like it will make an excellent gantry.

Art

Thanks Art , coming from you I take that as a huge compliment , I am going to re-size the pictures I posted on the other forum for showing your routers then found out how to re-size them so I hope I can edit these...
Gary