Machining a Denis Foster Machinist Straight Edge, Part 1

[@christinepryor5893]

It’s neat to see all of your previous projects around your shop. Not just a fair weather make-em look pretty machinist - you are actually using all of them. Very cool! 😀

[@KevinToppenberg]

Thanks! :-)

[@MyLilMule]

The challenges of having a small machine for big projects! I think you solved it the same way I would have, by rotating the turret. If it's just a small step, you should be able to step scrape it out. It's going to take a lot of work and a lot of passes, but I think you'll be able to do it. And thanks for considering me a friend, the sentiment is mutual!

[@KevinToppenberg]

I think if I were to do it again, I would depend more on turret rotation than table movement. When I would move the table to the end of it's travel, I think I was getting quite a bit of sag. If, instead, I had kept the travel more to the midline, and divided the milling into 4 parts (i.e. 4 turret positions), I think it would have been more even. And thanks for the friendship! Best wishes.

[@terrymoorecnc2500]

3/4" SC variable helix, unequal spacing, 4 X D minimum. 3.0" LOC in a solid holder, no collet.

[@zekestrom]

Kevin, Thanks for your well-made video documenting your hard work and the creativity you used to accomplish a job that is not easy. I am sure you learned much as you progressed through the various setup steps and cuts. I use a little different setup on my BP including a very useful Bridgeport right-angle head. But that still does require swinging the head as you did. The advantage of the RA head is that you can lay the SE on its side and securely 3-point it. Using that method and on my machine (which, by luck was in good condition when I bought it) and a lot of care I can get the sole flat to about .001 or better. Having the SE on its side and using the RA head tends to get around the typical knee mill table rocking and makes a solid but non-warping setup easier. If your sole is out .014" over its length, you might consider using an angle grinder to rough it down to within a couple thou of flat and then start scraping. That is not a technique I have used, but I have seen reports of folks doing that with good results. I think your thoughts about welding up fixtures to support the ends of the casting would get around the need for cutting steps and making the flat on the bow. Only light support would need to be made at the center of the span to keep down chatter. And by finishing with light cuts (.005") and a sharp face mill very little deflection will occur. Careful planning of clamping arrangements to avoid flexing the casting will be your friend as well. I look forward to more in the promised series of videos. Denis Foster

[@KevinToppenberg]

Here here! Everyone notice that this is the creator of the casting! Thank you so much for your comments. Yes, this was a learning process. I have had others recommend putting it on it's side and using a large endmill (which I have). If you were able to get to 0.001" on a bridgeport, then well done! I think if I did it again, using everyone's suggestions, I'd be happy to get to within 0.005" Regarding dealing with the 0.014", I ultimately succeed. Stay tuned for future videos (if you want). :-)

[@Chromevulcan]

Aside from the adventures in machining, I like that you ended your video with a Proverb. We need more people who aren't afraid to show their Christian values to the world!

[@KevinToppenberg]

I am Christian, but I like to think that the appeal is because it is also just good common sense!

[@machinewrangler4682]

Machine size and ambitions is an ongoing saga I think all machinists encounter. Then you get a bigger machine and take on even larger size jobs. See a few comments about moving the turret, and yes table sag is a good consideration also. I’d have been inclined to lay it on its side shim and clamp and run an endmill along the face. Just my 2cents from an escaped toolmaker.

[@KevinToppenberg]

I hadn't even thought of running an endmill along the face. I'll try to keep that in mind for next time. Thanks for the feedback and for watching!

[@davemciver6577]

Any plans for adding automatic feed to the milling table there Kevin?? Seems like you're having to do an inordinate amount of hand cranking. Maybe a future project. There are some great "home brew" solutions various people have come up with, if you don't want to invest in the commercial mechanism. Just a thought..

[@KevinToppenberg]

Yes, by the end of the video I had gotten tired of hand cranking and installed a power feed. Much nicer!

[@terrycannon570]

I agree with you and MyLilMule. . Seems we never have enough X-Y travel. Last year I added a BP Clone to my collection. I think it is advertised at a 52" table, but I can't remember what the actual work envelope is when I measured it but something around 49 seems to reside in my head. But of course, my head is not always my friend either. LOL I do enjoy your videos and also those of MyLilMule. I've been a subscriber for at least a year. Friendship seems to find its way into the Machinist/You Tube communities. Some would refer to the community as a family. Myself I divorced myself from Television in 2015. I prefer to soak my brain in good healthy knowledge. At age 72 time is short and knowledge is long. .002 is a lot to scrape. You may want to consider first draw filing the high spots before putting on that beautiful 36 x 48 Granite table you just got. I feel cheated when I look at my 6" x 18" Granite or my 18" x 18" cast iron surface plate compared to the 36 x 48 you have.

[@KevinToppenberg]

Thanks for your reply. We are a bit like family. It would be fun to meet at a get-together. If you think .002" is a lot to scrape, wait until we get to the scraping part. It is more like 0.014" ! Ha!

[@terrycannon570]

@@KevinToppenberg It looked like a very generous .002 to me also. LOL

[@RevyZero]

Great video! I noticed at 10:35 it looks like the saddle gib is extremely loose? either that or its the camera playing tricks on me lol.

[@KevinToppenberg]

Good eyes, and you are right. If I tighten up the gib further, I don't have range of travel, so I have to leave the gib loose and then constantly put the lock on that x axis. That has been part of my motivation to get a straight edge, so I might be able to try to fix it (big job that I am dreading). Thanks for watching!

[@RevyZero]

@@KevinToppenberg I have a Clausing Kondia mill with a similiar issue and am also currently working on a straight edge to fix the issue haha. Good luck with it!

[@jamesspallinger938]

I don't think you will ever get it flat with a bridgeport. Most tables are a couple of .001's out. With any flycutter finish you would be scraping for a year to get it flat. We had 4'x5' surface plates that were out by .0005 and had them refinished by a company that got them close. You need a good 6' grinder that holds a couple of tenths in that distance. I don't want to discourage you but after you go thru all the effort I think you will agree. I think a shop with a grinder like that would do it fairly cheap....then you can scrape.

[@KevinToppenberg]

You are right! When I finally get it done and onto the surface plate, I'm off by about 0.015". But never fear, I ultimately succeed. Stay tuned!