I had picked up the material I was going to use for making studs for the mounting plates. I even got three quarters of the way through when the problem arose. Having said that I did have some indication early on that I used the wrong material for my studs. So two problems occurred.
First problem. I had bought some 9/16" grade 8 bolts 3" long. This would give me a shank long enough for the mounting hole before the thread started. I carefully cut them up and tapered the ends to accept the weld bead. Here is a picture of the the process showing 4 bolts in various stages of the the work. I thought we were going so well.
Then the problems started. When I went to Tig weld the bolts to the back of the plate I noticed I was getting a lot of porosity. Now I am not an expert welder and I have not welded a lot however last time I welded I did not have this problem. So checked everything over checked on the internet for issues and really could not find anything initially that seemed to indicate the reasons. I had plenty of Argon the area was clean however the porosity continued. Eventually I managed to get enough clean weld to make it workable. However in later searching on the internet I noticed that welding grade 8 bolts was not recommended, one due altering the heat treating to make them grade 8, as well some people stated that the composition of some of the bolts would cause porosity issues. Although I will admit this was fifty/fifty from the stuff I found. So that was problem #1. At the same time that I found this out I also came across problem #2.
Second Problem. I had the first two studs mounted and the plate secured. I then mounted the overhead bracket and proceeded to drill out the hole required for the third stud. First picture below shows the bracket mounted prior to drill the third stud hole. Second picture is a close up of the plates after the top bolts are snugged down. There is a little gap between the bracket and the plate. However this is compensated for by the thread in insert in the overhead bracket. All 4 holes had a threaded insert with 9/16" dia hole that was screwed into the bracket and could compensate for the roughness of the lathe casting.
So drilled out the third hole and went over to do the fourth hole when I noticed that the fourth hole was being interfered by one of the mounting screws holding the plate to the lathe. On the picture below you can see the three studs inserted and if you look to the bottom left on the bottom plate i've put a mark where the hole would need to be drilled to accept the 4th stud. Essentially 1/4 of the stud hole would be in the hole from the mounting screw. When I initially laid out the marks I did not notice this.
So Monday afternoon down the road I go after work to pick up another 24 inches of 4" by 1/2" plate and I'm also going to pick up some 9/16 round stock to make new studs. So I guess next week I'll be doing things I did last week and making new plates and studs. This time when I go to mount the bracket I will move the mounting holes for the stud up 1/2". Since I do not have the belting for the lathe this should not be a problem. Moving the stud holes up 1/2" will clear the bolt hole on the bottom plate and on the top plate there were two holes inside the four shown that could also be used. So i'll use the same bottom two holes and then drill out the middle two holes so that I don't use the upper two holes. The hole on the upper right would clear the new stud hole however the hole on the upper left would be to close to the stud hole to be useable.
Until next week when hopefully I'll have better news enjoy the weather and enjoy life. And if you drink have a beer or scotch to commiserate with with me. I think tonight is a night for a Guinness.
Harold
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