Grinder plans

Joined
Jul 31, 2015
Messages
3,118
Here are some captures out of solid works. This is a modified eerf grinder. When I post the cad files, they include everything here except the tool arms. It will also have the tool rest. Let me know what you think.


ad4ae1ada4760bdd492e807d77ee2551.jpg
ae612ac6c34e214e56842dfaf2d4144e.jpg


Here is a link to the DXF file:
https://drive.google.com/file/d/0Bx...drivesdk&resourcekey=0-XtI6vaElAFKTftpQiRHccg
PDF:
https://drive.google.com/file/d/0Bx...drivesdk&resourcekey=0-PCiEQ14xBy1ZzfD2dIStcQ
materials:
https://drive.google.com/file/d/0Bx...drivesdk&resourcekey=0-A9f0bnaQ6eZ-tNVPUQN-7Q

Read me:
https://docs.google.com/document/d/12eh_t1AANl4K7D2eVnYK7Xixz-c7W5RTzxGq-MZ0Alk/edit?usp=drivesdk

Let me know if they don't work.

And here is what it looks like laid out on two 12"x 24" plates. Plates should be 1/2" if you intend to use this. just send the files to the waterjet guy, and you will get back what you see below. The holes to be tapped are undersized for that purpose. These have my mark on the main upright, the files I posted do NOT.

662f3e467d75f68d67dbc1795b49ab1a.jpg
5dc53ff74dec8f7b8e1e2729c77110f6.jpg


If anyone needs solidworks files, I have those as well.

7/31/2023- All links to files updated.
 
Last edited:
It looks like the belt tension will be a spring in the back pulling?

I think I would change it so you could use a gas shock, extend the top back some over the tool arm.

I don't know never used one like that but seems like a compressed spring or gas shock would be better.
 
It looks like the belt tension will be a spring in the back pulling?

I think I would change it so you could use a gas shock, extend the top back some over the tool arm.

I don't know never used one like that but seems like a compressed spring or gas shock would be better.

I left that up to the user, I will be using a gas shock, You just need to buy two mounts and bolt them to the bottom of the tension arm and one on top of the the left side tool arm retention plate. by not making mounts for the shock built in, you have more flexibility on what length of shock and it's position you can choose from.
 
How is the main upright mounted to the base?


Sent from my iPhone using Tapatalk

there is a tab on the upright and a corresponding hole on the base. There are holes in the base, that line up with holes YOU need to drill and tap in the bottom edge of the upright. I will be using flat head bolts that will be countersunk in the bottom plate. This is unchanged from the EERF design.
 
Looks great though, any plans for a tilt feature?

I will most likely accomplish this on my build by mounting it on a thick plywood base with a hinge. No plans to incorporate it into the design, I wanted to keep it on two 12"x 24" plates for water jet/ plasma cutting.
 
Kevin looks like you have some serious skill with drafting software...it takes me like 30 minutes to get a knife shaped object in CAD
 
the piece for the tracking that bolts solid to the arm looks like it needs to be a half inch longer. the wheel mounting half of the hinge should line up with the main plate when hanging vertical. you can always add more spacer behind the wheel, but its easier to measure for offset that way. have you seen the way i built mine with the over center cam and gas shock on top? this would be a good design to build like that. it would only require 3 small extra pieces and i guarantee you will not regret it. you could use a 3/8 or 1/2'' bolt for the pivot pin.
 
the piece for the tracking that bolts solid to the arm looks like it needs to be a half inch longer. the wheel mounting half of the hinge should line up with the main plate when hanging vertical. you can always add more spacer behind the wheel, but its easier to measure for offset that way. have you seen the way i built mine with the over center cam and gas shock on top? this would be a good design to build like that. it would only require 3 small extra pieces and i guarantee you will not regret it. you could use a 3/8 or 1/2'' bolt for the pivot pin.
I believe that's exactly how it lines up it may just be the rendering I posted looks different. Can you post a link to your tracking design? I lengthen the vertical arm on this design so the tracking arm can be almost parallel to the ground. I understand from other threads that this will Aid in tracking
 
Actually I think I lined it up so it is in line with the D plate

That's where it should be IMO. If they line up with the main plate, fine, if they don't, fine, as long as they're parallel to it they'll be parallel to the drive wheel. Whether they're in the same plane only effects how many or few spacers you need to keep your belt off of the plates and how much engagement the drive wheel has with the motor shaft.

Keeping the tension arm parallel in nominal conditions keeps the hinge in relation to the axis of the belt where it will provide the most and most consistent tracking adjustment per angle of increment. As it swings out of parallel, the movement becomes more and more unrelated to the belt, and belt tension against the hinge is decreased.
 
Can you put the tension arm in double shear as opposed to single? Might stay tighter like that.
 
What do you mean? Two pieces? It's half inch thick so I don't think flex will be a problem. At least I've never heard of it being one on similar GIBs or EERF builds.
 
the piece for the tracking that bolts solid to the arm looks like it needs to be a half inch longer. the wheel mounting half of the hinge should line up with the main plate when hanging vertical. you can always add more spacer behind the wheel, but its easier to measure for offset that way. have you seen the way i built mine with the over center cam and gas shock on top? this would be a good design to build like that. it would only require 3 small extra pieces and i guarantee you will not regret it. you could use a 3/8 or 1/2'' bolt for the pivot pin.

I just checked ARCustomKnives youtube video on this. I think I'll forgo it for now. I already got a lot of work out of my CAD guy.
 
Some of the pieces for the tool rest I am not sure of their function. They are native to the eerf plans. I just left them.
 
Back
Top