dgfoster
Diamond
- Joined
- Jun 14, 2008
- Location
- Bellingham, WA
I have just cast my prototype small flat-bottomed 8.5" long, 2"high,1.62 at the base Prism/Parallel/ Straight edge.
It is designed to accommodate (with some machining) almost any of the precision tubular machinists vials currently on the market as well as a cross-level. I plan to drop long vial into a pocket with side windows into the top of the casting and will cross drill the top rail for the cross-level vial.
I will be machining it over the next few days and will order a couple vials to demonstrate their placement.
The casting currently weighs 4# 14oz and likely will lose a half pound or so when machined. As you can see in one of the pics, it fits nicely into the hand and should have just enough heft to make it stable and solid on the granite or machine way. There is a step-off to facilitate scraping the angled prism surface. That surface is currently 3/4" long, but will likely lose an eighth in machining.
Those with sharp eyes will notice below a shrink defect where the gate entered the casting. Likely it will machine out as it is only 1/16th deep, but for future castings I will try a different location for the gate/riser combination I used so that this is not an issue. Getting my other castings right required some experimentation as only an educated guess can be made as to how the gate and riser will interact with the casting as it cools and sucks metal from the riser.
Since this is a prototype, nothing is cast in stone--just iron ;-) Patterns can be changed. Suggestions welcome.
Denis
It is designed to accommodate (with some machining) almost any of the precision tubular machinists vials currently on the market as well as a cross-level. I plan to drop long vial into a pocket with side windows into the top of the casting and will cross drill the top rail for the cross-level vial.
I will be machining it over the next few days and will order a couple vials to demonstrate their placement.
The casting currently weighs 4# 14oz and likely will lose a half pound or so when machined. As you can see in one of the pics, it fits nicely into the hand and should have just enough heft to make it stable and solid on the granite or machine way. There is a step-off to facilitate scraping the angled prism surface. That surface is currently 3/4" long, but will likely lose an eighth in machining.
Those with sharp eyes will notice below a shrink defect where the gate entered the casting. Likely it will machine out as it is only 1/16th deep, but for future castings I will try a different location for the gate/riser combination I used so that this is not an issue. Getting my other castings right required some experimentation as only an educated guess can be made as to how the gate and riser will interact with the casting as it cools and sucks metal from the riser.
Since this is a prototype, nothing is cast in stone--just iron ;-) Patterns can be changed. Suggestions welcome.
Denis