Hi Guys,
Following on from from some of the posts made here, including mine, discussing various alignment issues with lathes and being aware that bed twist, particularly on small lathes can be a problem, I decided to try to build myself a Machinists Level. Having seen and used a "Starret" machinists level, I thought that something along those lines could be doable.
The picture above is one I found on the net of the type of construction that I want to build. It is basically a tube containing a vial that is supported at each end on a cast iron base. The tube is adjustable at each end so that the bubble can be centred easily.
Now I don't have any cast iron suitable for this job so I propose to use brass, not just for the base, but all the parts. The vial is one extracted from a "Pound" (Dollar) store spirit level. The one I bought was 12 inches long and made from an alloy casting. It had three vials two small ones and one larger one. I used the larger one. However I also found a supplier of low cost precision vials on the internet. Unsurprisingly almost exactly the same size as the one I extracted from the store bought level.
The picture on the left is the salvaged one and the one on the right is the one I found on the net. As you can see the salvaged one only has two graduations where as the other has six, three on each side of the bubble.
Below: These are the details of a supplier and details of the vial. Both vials have the same dimensions. However the sensitivity of the salvaged one seemed to be higher. I could detect bubble movement when I shoved a 1/1000 feeler gauge under one end of the level that I bought.
http://ift.tt/16iwugc
Vial cylindrical (Tubular Vial)
Length: 40 mm
Diameter: 9,5 mm
Sensitivity: 0.35mm/m=0.020"
Order nr. 312141 cart
Price US $ 4.80
These are the pieces of brass that I am going to use to make my machinists level. There are eight pieces in all. Only five shown here. Plus two fibre washers and the vial. The two pieces of brass in the lower half of the photograph are going to be soldered together to form a "T" section. The bottom plate has already been fly cut so that it is as flat as I can make it. The holes at the ends have been drilled and threaded M8. Then I used solder paste wiped on the bottom of the vertical piece. Aligned it on the base then put the whole lot on a hot plate to solder it together.
The brass tube is 10 mm OD and the 9.5 mm diameter vial is a good sliding fit inside. The two 1/2" diameter brass pillars are heater supports from a Hotpoint top loading washing machine, as are the fibre washers. You can see that I've turned and threaded one of them M6. I did the same to the other one.
More later:
Following on from from some of the posts made here, including mine, discussing various alignment issues with lathes and being aware that bed twist, particularly on small lathes can be a problem, I decided to try to build myself a Machinists Level. Having seen and used a "Starret" machinists level, I thought that something along those lines could be doable.
The picture above is one I found on the net of the type of construction that I want to build. It is basically a tube containing a vial that is supported at each end on a cast iron base. The tube is adjustable at each end so that the bubble can be centred easily.
Now I don't have any cast iron suitable for this job so I propose to use brass, not just for the base, but all the parts. The vial is one extracted from a "Pound" (Dollar) store spirit level. The one I bought was 12 inches long and made from an alloy casting. It had three vials two small ones and one larger one. I used the larger one. However I also found a supplier of low cost precision vials on the internet. Unsurprisingly almost exactly the same size as the one I extracted from the store bought level.
The picture on the left is the salvaged one and the one on the right is the one I found on the net. As you can see the salvaged one only has two graduations where as the other has six, three on each side of the bubble.
Below: These are the details of a supplier and details of the vial. Both vials have the same dimensions. However the sensitivity of the salvaged one seemed to be higher. I could detect bubble movement when I shoved a 1/1000 feeler gauge under one end of the level that I bought.
http://ift.tt/16iwugc
Vial cylindrical (Tubular Vial)
Length: 40 mm
Diameter: 9,5 mm
Sensitivity: 0.35mm/m=0.020"
Order nr. 312141 cart
Price US $ 4.80
These are the pieces of brass that I am going to use to make my machinists level. There are eight pieces in all. Only five shown here. Plus two fibre washers and the vial. The two pieces of brass in the lower half of the photograph are going to be soldered together to form a "T" section. The bottom plate has already been fly cut so that it is as flat as I can make it. The holes at the ends have been drilled and threaded M8. Then I used solder paste wiped on the bottom of the vertical piece. Aligned it on the base then put the whole lot on a hot plate to solder it together.
The brass tube is 10 mm OD and the 9.5 mm diameter vial is a good sliding fit inside. The two 1/2" diameter brass pillars are heater supports from a Hotpoint top loading washing machine, as are the fibre washers. You can see that I've turned and threaded one of them M6. I did the same to the other one.
More later:
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