I was just doing some research [wasting time] on YouTube and came across a guy building a table top using concrete mortar mix. It is impressive, because it is so easy and would make a great lathe bench. Or at least that is what I thought after watching it. I was thinking about finding a section of granite counter top large enough to use as a lathe bench but this is better. Better because I can make it any dimension I want, it is super strong, it can be light or it can be heavy as you wish and you ever try to drill granite? Lets just say this, you definitely don't want to, it takes diamond bits and it is hell.




The cast bench top can be made heavy in an attempt to strengthen the lathe and damp vibration. The mortar mix is "much" stronger then regular concrete. It can be poured from 1 inch to 6 inches thick, sets up super fast, has very little shrinkage and can even be deployed in as little as an hour. In the video the guy used a plasticizer additive that smooths out the mix and makes it much more easy to work.

if this interest you watch the video, the guy does a good job on the video, it moves right along and is detailed enough so you can easily replicate what he does with little special skills,or if you got concrete skills you could do some very cool stuff with this mortar mix method. I'm thinking if I do this, and I probably will, I am going to attempt to cast some custom I-beam lags for my lathe bench with round holes in the main beam section and precast holes for bolting the legs on and inserts for leveling feet. You could even make your cast bench top special made with pre-drilled plates to use the cast lathe bench lags. I have a set, my lathe came on but I wanted something more heave duty so I made a rolling workbench out of those.

You could use blocks of wood embedded in the mold to make voids in the cast bench for lighter weight but with a honey cone or square relief pattern on the bottom for strength and lightness. If you watch the video you can see what I mean on how you could place these into the mold. On the video he made the mold out of melamine faced particle board and the top of the pour is actually the bottom of his table. If I did it, I would make the bottom of the mold the bottom of the bench. Then trowel finish and level the top of the poured concrete while embedding 2 large plates with pre-drilled and threaded holes for bolting the lathe down. The mounting plates would only need be "close" to level, you would be shimming it to level the lathe bed perfectly any way. I can tell you, it is worth getting a precision level and going through the trouble to level your lathe bed to perfection. I see the difference in Turing longer items and my saddle and my tail stock ride the entire length of their travel much smoother then before the lathe was leveled.

If you do some research on precast concrete you can see the applications for this mortar mix could well be almost unlimited if you want to get creative making things. The mortar mix is not cheap but neither is steel or good wood. In fact this looks like it could be reasonably cheaper then steel or wood and better due to the possible vibration damping effect. The guy in the video used 2 55 lb bags of mortar mix and his table is 1.5 inches thick, he did not give dimensions that I saw but his table is reasonably good sized.

The concrete bench top could be painted with any color epoxy concrete sealer or garage floor paint/sealer and it would look a lot nicer then raw concrete and be oil proof, well, as much as any garage floor epoxy would be any way.

Let me know if you like this idea or you think I might be better off making a set of concrete boots and being thrown into a lake... haha

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Saw that video this weekend. Then showed it to my wife. Between us we've now got at least 3 different Spring projects planned. Would be interesting to see how well that would work as a work surface. I'd be interested how well it holds bolds for attaching my lathe to the surface. I would think about 4-5 bags would be enough for my 12x18 as his table was just about the size of of my benchwork. That would give a top nearly 4 inches thick. One could even cast a bit of a sump under the lathe bed for stuff to accumulate!
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Jim Korman

For what ever reason my lathe bed has a vary slight twist to it. It needs a stronger bench to be attached to so the lathe can be shimmed to untwist the lathe bed so it is dead straight/level. I'm sure it probably left the factory straight but now it has a twist probably due to stress in the casting.

Making a bench like this might be a good way to get a bench to what ever dimension you need and have it be strong enough and stable also.

If you don't need or want such a stable strong heavy duty bench does not mean no one else might.

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开云体育

How did you? discover a twist in the bed of your lathe. - By using a precision level, the kind you can tell if it is out of level by .0005 and is normally used to level machine tools.

In this case it is made by shars, but it is accurate, I had to calibrate it, that took a while and was tedious but in the end, I got it reading easily less then .001 over 8" as that is how long it is.

How I tested the level, I loosened one end of the lathe mounting, the tail stock end, then stuck a shim under the center so it was able to move where ever it wanted. The other end was snug but not tight.

I measured the level of the head stock end and shimmed it close to exact level. Next I took a measurement of level on the tail stock end.

Could that have put in there by tightening down the mounting bolts? not sure, it could have but when I mounted the lathe I did not see a difference from one end to the other, when I tightened it down I looked for indications it was being pulled forward or backward out of level back when I mounted it to the bench. As much as I could tell, there was no binding or twist put in to it due to the mounting on the bench.

After I leveled it, a lengthy process of tightening down one end then the other and taking measurements and shimming and doing this over again until I felt everything was in sync and the lathe bed was reading at .0005 or less in level from one end to the other, I called it good.

What I noticed, seemed to cut a little better when I take a long cut on a shaft, completely unscientific just seemed better.

What was the most noticeable difference though was how well and smooth the carriage and tail stock moved over the entire travel. Previously, when i lubed the bed so the carriage and the tail stock moved I thought it was fine. After I leveled the bed what I noticed was the travel seemed more smooth and the kind strange part was the lube seemed to stay in place better as if before it was being skinned off and after it seemed to last longer and be smoother for longer.

I think the slight twist was causing the lube to be skimmed off on one side? Not exactly sure though but the smooth operation and travel from one end to the other, even with very light lube such as WD40, it seemed smoother, yes that is my unscientific evaluation but I had this lathe for 8 yrs and use it almost every day to make small parts for my business, we are friends and I know it well. So my evaluation is subjective but my lathe IS SMOOTHER after leveling it, there is no doubt to me.

This was with the exact same oil I used and have been using, Mobil Vactra 2 Oil

I bought this level for my Enco 14x40 lathe that I'm still finishing up but since that is taking a while I decided to first use it on the little craftsman 12x36 to see if it would do any good to level it.

I totally recognize there will be many people who think going through this trouble on a craftsman lathe is a waste of time, my lathe made good parts before I leveled it, now it is still making good parts, just seems a bit smoother and feels a bit better.

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