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Tool and cutter grinder build
- Thread starter Mark_f
- Start date
- Joined
- Oct 20, 2014
- Messages
- 495
I was going to suggest that, or a piece of hydraulic piston. However, hydraulic piston is pretty tough to machine. I would think that the chrome shock rod would be easier.
Drill rod is pretty uniform in diameter, but it's centerless ground, so it will still have 'lobes' on it. When a centerless grinder gets out of whack, it'll make nice triangular stock...
You may have a look at a piece of hard chromed linear shafting. It isn't exactly cheap, but it's ground to very close tolerances, and usually hard chromed.
Maybe an old bottle jack could provide the stock you need? I've seen those pretty cheap at flea markets.
Drill rod is pretty uniform in diameter, but it's centerless ground, so it will still have 'lobes' on it. When a centerless grinder gets out of whack, it'll make nice triangular stock...
You may have a look at a piece of hard chromed linear shafting. It isn't exactly cheap, but it's ground to very close tolerances, and usually hard chromed.
Maybe an old bottle jack could provide the stock you need? I've seen those pretty cheap at flea markets.
Didn't get much done for spending 4 hours in the shop. I think most of it went on the tiny brass indicator for the work head arm. The little sucker is .187" diameter and .250" long and half of that .250" is a little .125" x .125" peg machined on the back end. I just ain't used to machining something this small. I made three before I one one satisfactory. I also made the two handles that lock everything. I have the holes drilled for the bar through the handles , but trying to decide how I want them to look. The plans call for a rod pressed into the hole and centered. I am not sold on that. I am thinking sliding handles like on a vise, but the bars steel and the little button ends brass. be a lot more work but I think a lot classier too.
You can see the little brass thingy in the bottom slot that gave me so much trouble. It is just an indicator mark to set the angle of the head. There will be a brass scale under that bottom slot.
The lower half of the work head is near completion. Still have to make the split cotters, but waiting on the material to get here. It is assembled for good though. I test fit it on the base to see how it looks. I like it. I will engrave the degree markings on the table a little later in the build.
I wanted to start the tool holder for the top of the work head. the piece of 2" square steel I planned to use was, as it turns out , a 1/2" too short. I am trying to figure a way to cut the plans down enough to make up the difference, but it ain't looking good. I bought this piece for $15. the stuff is $28/ foot :yikes:. Only other option is to look for another piece as this was the last the closest supplier had. So far this machine is all steel, I don't know if aluminum would be good for this part or not. I may have a piece of aluminum big enough. I would be afraid of wear, but i don't know. Any opinions?
I spent five hours editing some of the plans today.
You can see the little brass thingy in the bottom slot that gave me so much trouble. It is just an indicator mark to set the angle of the head. There will be a brass scale under that bottom slot. The lower half of the work head is near completion. Still have to make the split cotters, but waiting on the material to get here. It is assembled for good though. I test fit it on the base to see how it looks. I like it. I will engrave the degree markings on the table a little later in the build.I wanted to start the tool holder for the top of the work head. the piece of 2" square steel I planned to use was, as it turns out , a 1/2" too short. I am trying to figure a way to cut the plans down enough to make up the difference, but it ain't looking good. I bought this piece for $15. the stuff is $28/ foot :yikes:. Only other option is to look for another piece as this was the last the closest supplier had. So far this machine is all steel, I don't know if aluminum would be good for this part or not. I may have a piece of aluminum big enough. I would be afraid of wear, but i don't know. Any opinions?
I spent five hours editing some of the plans today.
- Joined
- Mar 21, 2013
- Messages
- 4,122
I like the idea of the sliding handles with brass ends. Should look good. Or you could do those snazzy Quorn ball handles. I still like those things. 
For the tool holder I'm not sure on the aluminum. If I were doing this and wanted/needed to use the aluminum I might put a thin steel plate on potential wear surfaces. Maybe even loctite them into a shallow pocket on the aluminum. These are just ideas as I don't have a picture in my head of the tool holder and how it operates. What page of the drawings would I find it on?
For the tool holder I'm not sure on the aluminum. If I were doing this and wanted/needed to use the aluminum I might put a thin steel plate on potential wear surfaces. Maybe even loctite them into a shallow pocket on the aluminum. These are just ideas as I don't have a picture in my head of the tool holder and how it operates. What page of the drawings would I find it on?
I like the idea of the sliding handles with brass ends. Should look good. Or you could do those snazzy Quorn ball handles. I still like those things.
For the tool holder I'm not sure on the aluminum. If I were doing this and wanted/needed to use the aluminum I might put a thin steel plate on potential wear surfaces. Maybe even loctite them into a shallow pocket on the aluminum. These are just ideas as I don't have a picture in my head of the tool holder and how it operates. What page of the drawings would I find it on?
I think those Quorn handles are ugly. I am getting pretty set on the sliding handles with brass ends, unless someone comes up with something better.
The tool holder is drawings H1 thru H6. Particularly 3 & 4 that is the part.
B
Bill Gruby
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The Quorn Handles are ugly. I used all T-handles.
"Billy G"
"Billy G"
- Joined
- Mar 21, 2013
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- 4,122
Well you're the one driving this bus, so I'm good with whatever you decide. I was just curious how you'd make those handles anyway. :lmao:
After looking at the tool head I personally wouldn't do aluminum here. But that's just me. I just did a quick check at Speedy Metals and yea this stuff is spendy. I could buy 8" of the stuff and we could split it?)
Just curious, but what type of steel are you using for this thing? Not being a metallurgist I would probably do gross overkill and use 4140 for everything when 10L18 would probably suffice. Definitely not De-carb though. That stuff is REALLY spendy!
I can see me having over $500 in just materials on this thing... :rofl:
After looking at the tool head I personally wouldn't do aluminum here. But that's just me. I just did a quick check at Speedy Metals and yea this stuff is spendy. I could buy 8" of the stuff and we could split it?
)Just curious, but what type of steel are you using for this thing? Not being a metallurgist I would probably do gross overkill and use 4140 for everything when 10L18 would probably suffice. Definitely not De-carb though. That stuff is REALLY spendy!
I can see me having over $500 in just materials on this thing... :rofl:
Well you're the one driving this bus, so I'm good with whatever you decide. I was just curious how you'd make those handles anyway. :lmao:
After looking at the tool head I personally wouldn't do aluminum here. But that's just me. I just did a quick check at Speedy Metals and yea this stuff is spendy. I could buy 8" of the stuff and we could split it?
Just curious, but what type of steel are you using for this thing? Not being a metallurgist I would probably do gross overkill and use 4140 for everything when 10L18 would probably suffice. Definitely not De-carb though. That stuff is REALLY spendy!
I can see me having over $500 in just materials on this thing... :rofl:
Yes,you can put some money in the material. I just used mild steel. All cold finsh...... No hot roll. I have about $125 in material so far and I had a little of it. $250 to $300 should cover materials. Then you still have to have a motor and grinding wheels. But this machine will out perform many of the commercial machines costing near $5000. I used some really nice cold finish rod for my bars. They should have been ground but I couldn't afford $100 for ground bar stock. $5 was better than $100 for me.
As long as you try to keep your tolerances as perfect as possible, you will end up with an accurate machine.
I have a friend that is a truck driver, I will look into that.
Most of today was spent doing small details. it seems they take as much time as the actual building, but they must be done.
I started by using a medium valve grinding compound to lap the 90 degree bearing and seat to a 100% contact fit. These types angled seat and bearing were popular as far back as 100 years ago on machinery with rotating tables. the bearings were hand scraped to fit the hand scraped seat and the table floated on an oil film when running. they were usually cast iron and worked excellent. I think the designer used this type of bearing because on a table like this, whether large or small , the table is very stable and there is no wobble or movement. the angled fit keeps the table solid and extremely accurate. Also, you can see the threaded insert in the bottom of the shaft of the table. This was made an put in with loc-tite. the end of the insert sicks out of the base a few thousandths (.025" to be exact).
This is a special washer. ( I hate making these tiny parts). It fits the bottom of the table spindle to hold it in the block. It is held with a 10-32 screw. Notice it has a recess on the one side. This recess is .026" deep to fit the spindle end and have .001" clearance so the table spins freely but can't move up and down. I hand filed this washer face to get the clearance down to a couple tenths ( .0005" or less).
The washer is installed and the table spins freely but with no detectable movement. the angle bearing works great like it is suppose to. The table will be removed one more time to engrave the degree markings and then permanently assembled.
Next was to finish up the micrometer for the front bar. I discovered by changing an item's size or type of setup, it changes many other things down the line that may not be thought of at the time. this was one of those changes. The Bonelle micrometer was way over engineered and the Quorn grinder had a simpler micrometer setup, so I chose it. Now I noticed that with .5" of mic travel the bar was losing .5" of bearing surface in a bearing 1.5" long. I was not happy about this and if thought out in the beginning, I would have left the ends of the base 2" thick instead of following the plan and cutting them to 1.5". Oh well.... can't put it back, so I made a revision to only have .250" maximum movement in either end at any time. this is done by putting a .280" spacer between the micrometer and the base. The other end is revised also, but we'll talk about that later. This revision works perfectly so I am pleased with the outcome.
Something that was not in the design was the steel ball bearing. The original design had the .5" micrometer screw pushing the bar when turned. That seems like a lot of friction surface, so I center drilled the end of the bar half the depth of the ball and used loc-tite to hold it in the bar's end. The screw will now have a very small contact point on the .375" ball making it much smoother to turn. Since it is sealed and hidden inside, a small dab of grease will be placed on the ball at completion.
This is the completed micrometer. It is installed for the last time now. The spacer works perfectly. the bar can still be removed from the other end for assembly of the other parts.
I am getting ready to start the tool holder that sits on this rotary base. I decided to use 5C collets on the grinder because I can get square collets that are good for grinding lathe tools and the size selection is better. this has now created a new problem. The collet spindle is bigger and longer thus requiring the unit to be bigger. I had previously purchased the last piece of steel my local supplier had ( paid $15 for it) AND IT IS TOO SMALL, by an inch.
anic: I went looking for a way out of this mess and found a 3" diameter piece of aluminum round bar. I am figuring on paper how to save my butt here. I can saw this down to a two inch square and have enough room to bore the 1.5" bore for the spindle. I think that part is doable. I wish it was bigger ...but, that's life. Now it is 2" long and the spindle requires 3 inches. I think I can shorten the spindle .5" without hurting anything and I am hoping maybe a spacer on the spindle for the nut to screw up against, or leave the spindle unaltered and try using a 1 inch spacer. I am drawing it out on paper to see if it will work :nuts:. I am not too crazy about cobbing up an important part like this but ya gotta do what ya gotta do. A 3" square x 6" long piece of steel or aluminum is impossible to find around here an way too expensive online, but I may have to wait for one. I will make this decision tomorrow.
I am tired tonight. I had some recurring symptoms today, much like the stroke I had a few weeks ago, so going to the hospital tomorrow. Man I hope they don't keep me. I am just having too much fun right now for this crap. If all goes well we will see what I can get done tomorrow. Stay tuned boys and girls.
I started by using a medium valve grinding compound to lap the 90 degree bearing and seat to a 100% contact fit. These types angled seat and bearing were popular as far back as 100 years ago on machinery with rotating tables. the bearings were hand scraped to fit the hand scraped seat and the table floated on an oil film when running. they were usually cast iron and worked excellent. I think the designer used this type of bearing because on a table like this, whether large or small , the table is very stable and there is no wobble or movement. the angled fit keeps the table solid and extremely accurate. Also, you can see the threaded insert in the bottom of the shaft of the table. This was made an put in with loc-tite. the end of the insert sicks out of the base a few thousandths (.025" to be exact). This is a special washer. ( I hate making these tiny parts). It fits the bottom of the table spindle to hold it in the block. It is held with a 10-32 screw. Notice it has a recess on the one side. This recess is .026" deep to fit the spindle end and have .001" clearance so the table spins freely but can't move up and down. I hand filed this washer face to get the clearance down to a couple tenths ( .0005" or less). The washer is installed and the table spins freely but with no detectable movement. the angle bearing works great like it is suppose to. The table will be removed one more time to engrave the degree markings and then permanently assembled. Next was to finish up the micrometer for the front bar. I discovered by changing an item's size or type of setup, it changes many other things down the line that may not be thought of at the time. this was one of those changes. The Bonelle micrometer was way over engineered and the Quorn grinder had a simpler micrometer setup, so I chose it. Now I noticed that with .5" of mic travel the bar was losing .5" of bearing surface in a bearing 1.5" long. I was not happy about this and if thought out in the beginning, I would have left the ends of the base 2" thick instead of following the plan and cutting them to 1.5". Oh well.... can't put it back, so I made a revision to only have .250" maximum movement in either end at any time. this is done by putting a .280" spacer between the micrometer and the base. The other end is revised also, but we'll talk about that later. This revision works perfectly so I am pleased with the outcome. Something that was not in the design was the steel ball bearing. The original design had the .5" micrometer screw pushing the bar when turned. That seems like a lot of friction surface, so I center drilled the end of the bar half the depth of the ball and used loc-tite to hold it in the bar's end. The screw will now have a very small contact point on the .375" ball making it much smoother to turn. Since it is sealed and hidden inside, a small dab of grease will be placed on the ball at completion. This is the completed micrometer. It is installed for the last time now. The spacer works perfectly. the bar can still be removed from the other end for assembly of the other parts.I am getting ready to start the tool holder that sits on this rotary base. I decided to use 5C collets on the grinder because I can get square collets that are good for grinding lathe tools and the size selection is better. this has now created a new problem. The collet spindle is bigger and longer thus requiring the unit to be bigger. I had previously purchased the last piece of steel my local supplier had ( paid $15 for it) AND IT IS TOO SMALL, by an inch.
anic: I went looking for a way out of this mess and found a 3" diameter piece of aluminum round bar. I am figuring on paper how to save my butt here. I can saw this down to a two inch square and have enough room to bore the 1.5" bore for the spindle. I think that part is doable. I wish it was bigger ...but, that's life. Now it is 2" long and the spindle requires 3 inches. I think I can shorten the spindle .5" without hurting anything and I am hoping maybe a spacer on the spindle for the nut to screw up against, or leave the spindle unaltered and try using a 1 inch spacer. I am drawing it out on paper to see if it will work :nuts:. I am not too crazy about cobbing up an important part like this but ya gotta do what ya gotta do. A 3" square x 6" long piece of steel or aluminum is impossible to find around here an way too expensive online, but I may have to wait for one. I will make this decision tomorrow.I am tired tonight. I had some recurring symptoms today, much like the stroke I had a few weeks ago, so going to the hospital tomorrow. Man I hope they don't keep me. I am just having too much fun right now for this crap. If all goes well we will see what I can get done tomorrow. Stay tuned boys and girls.
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