- Thread starter Bsmith
- Start date
just over 2Hp,
2.41 if you want to nit pick
Thats a canny size grinding wheel, as long as your running within its rated RPM spec.
Depends how hard you want to grind. Many of the 150mm cheapo stuff is only 1/2Hp, or even a lot less.
Stan
2.41 if you want to nit pick
Thats a canny size grinding wheel, as long as your running within its rated RPM spec.
Depends how hard you want to grind. Many of the 150mm cheapo stuff is only 1/2Hp, or even a lot less.
Stan
Ok thank you ford34/2
That's like 1800w / 746 = 2.41
When I work it out by amps 11 x 240 / 746, I get 3.5. What am I doing wrong?
Grinding wheel has been safety tested to 2700 rpm. I remember a 12 inch wheel on a grinder that used to wear away quite quickly, think the rpm was to slow at 1500 rpm. So was thinking 1700 - 1800rpm
That's like 1800w / 746 = 2.41
When I work it out by amps 11 x 240 / 746, I get 3.5. What am I doing wrong?
Grinding wheel has been safety tested to 2700 rpm. I remember a 12 inch wheel on a grinder that used to wear away quite quickly, think the rpm was to slow at 1500 rpm. So was thinking 1700 - 1800rpm
as long as your sure on RPM, many manufacturers of 12" seem to be specking about 2070RPM.
so you should be safe at 1700
Mounting
All mountings shall only be done by competent persons appointed in writing by the
proprietors. Competent persons should be well trained and have the practical
experience in the mounting job. (See form in Fig. 5 for appointment of a competent
person.)
A wheel should not be mounted on a machine for which it is not intended and certainly
not on any make-shift apparatus or where there is vibration of the machine.
Check for soundness of the wheel before it is mounted.
Do not mount a wheel on a machine the speed of which exceeds the maximum
permissible speed of the wheel.
Washers, either paper or other compressible material, should be used with all bonded
abrasive wheels, except tapered wheels, threaded-hole wheels, discs, cylinder wheels,
and the hub section of depressed-centre wheels. Washers should be slightly larger
than the flanges and there should be no wrinkles in them.
The bush, if any, should not project beyond the sides of the wheel.
*
The wheel should fit freely but not loosely on the spindle.
Flanges should not be less than one-third of the diameter of the wheels and their
bearing surfaces should be true and free from burrs.
With the exception of the single flange used for threaded-hole wheels, all flanges
should be properly recessed or undercut.
Flanges on both sides of the wheel should have the same outside diameter and
diameter of recess.
Clamping nuts and screws should be tightened uniformly in pattern formation
(diametrical sequence) and only sufficiently to hold the wheel firmly.
Work-rests
For bench and floor stand grinders, a work-rest has to be provided and properly adjusted
as close as possible, in any case not exceeding 3.2mm (1/8 inch), to the wheel. Lack of
adjustment is the cause of many serious accidents in that the workpiece was jammed
between the wheel and the work-rest which forced the operator’s fingers against the
wheel face
Guards
*
Unless the nature of the work absolutely precludes its use, a guard shall be provided
and kept in position at every abrasive wheel for the following purposes:
(1) to hold the wheel parts in the event of breakage.
(2) to protect the wheel from accidental damage.
(3) to prevent the operator from coming into contact with the wheel.
(4) to prevent an oversized wheel from being fitted.
Guards must be of rigid construction, proper dimensions and securely anchored to
the machine frame. For maximum protection, the guards have to be adjusted to limit
the exposure angles
Before operating a bench or floor stand grinding wheel, ensure the proper provision
and adjustment of:
(1) the wheel guards with minimum exposure angle
(2)the clearance between the work-rest and the wheel
should be less than 3.2 mm (1/8”
Stan
so you should be safe at 1700
Mounting
All mountings shall only be done by competent persons appointed in writing by the
proprietors. Competent persons should be well trained and have the practical
experience in the mounting job. (See form in Fig. 5 for appointment of a competent
person.)
A wheel should not be mounted on a machine for which it is not intended and certainly
not on any make-shift apparatus or where there is vibration of the machine.
Check for soundness of the wheel before it is mounted.
Do not mount a wheel on a machine the speed of which exceeds the maximum
permissible speed of the wheel.
Washers, either paper or other compressible material, should be used with all bonded
abrasive wheels, except tapered wheels, threaded-hole wheels, discs, cylinder wheels,
and the hub section of depressed-centre wheels. Washers should be slightly larger
than the flanges and there should be no wrinkles in them.
The bush, if any, should not project beyond the sides of the wheel.
*
The wheel should fit freely but not loosely on the spindle.
Flanges should not be less than one-third of the diameter of the wheels and their
bearing surfaces should be true and free from burrs.
With the exception of the single flange used for threaded-hole wheels, all flanges
should be properly recessed or undercut.
Flanges on both sides of the wheel should have the same outside diameter and
diameter of recess.
Clamping nuts and screws should be tightened uniformly in pattern formation
(diametrical sequence) and only sufficiently to hold the wheel firmly.
Work-rests
For bench and floor stand grinders, a work-rest has to be provided and properly adjusted
as close as possible, in any case not exceeding 3.2mm (1/8 inch), to the wheel. Lack of
adjustment is the cause of many serious accidents in that the workpiece was jammed
between the wheel and the work-rest which forced the operator’s fingers against the
wheel face
Guards
*
Unless the nature of the work absolutely precludes its use, a guard shall be provided
and kept in position at every abrasive wheel for the following purposes:
(1) to hold the wheel parts in the event of breakage.
(2) to protect the wheel from accidental damage.
(3) to prevent the operator from coming into contact with the wheel.
(4) to prevent an oversized wheel from being fitted.
Guards must be of rigid construction, proper dimensions and securely anchored to
the machine frame. For maximum protection, the guards have to be adjusted to limit
the exposure angles
Before operating a bench or floor stand grinding wheel, ensure the proper provision
and adjustment of:
(1) the wheel guards with minimum exposure angle
(2)the clearance between the work-rest and the wheel
should be less than 3.2 mm (1/8”
Stan
brightspark
Member
- Messages
- 40,158
- Location
- yarm stockton on tees
safety yes but in private workshops it makes no odds and u dont need to comply with anythingI didn't know about all these safety regs.
I built the 12 x 2 inch double wheel grinder in this pic about 20 years ago, 1800rpm, 3hp motor. Never had any probs with it.View attachment 60980
Have started making the grinder so posting pics as I progress, any disapprovals welcome.
Need to make a 3 vee pulley (spz belts) for the motor, from a piece of this.
Grinding wheel spindle next, piece of 32mm dia bright steel shaft.
Making the grinding wheel flanges.
Let's see how it looks together, had adapted a spindle pulley before I thought on taking the camera with me.
Have fastened inner grinding wheel flange to the spindle with 3 grub screws, in case it spins on shaft.
Need to make a 3 vee pulley (spz belts) for the motor, from a piece of this.
Grinding wheel spindle next, piece of 32mm dia bright steel shaft.
Making the grinding wheel flanges.
Let's see how it looks together, had adapted a spindle pulley before I thought on taking the camera with me.
Have fastened inner grinding wheel flange to the spindle with 3 grub screws, in case it spins on shaft.
Thanks Shox Dr, Can I do that somehow?
Done. Thanks for suggesting (",).
brightspark
Member
- Messages
- 40,158
- Location
- yarm stockton on tees
a 1 and a half or 2hp will be well fine for that job .nice looking project .carry on good work
Motor slides and fasteners made today. Channels have been in use before and have a bit of surface rust but good enough for me.
Couple of belt tensioners, welds are a bit cold but I'll sort them when I take the motor off.
Tack weld onto spindle housing
Clamp onto piece of plywood and test run, runs nice and smoothly. Spindle running at 1725rpm.
Couple of belt tensioners, welds are a bit cold but I'll sort them when I take the motor off.
Tack weld onto spindle housing
Clamp onto piece of plywood and test run, runs nice and smoothly. Spindle running at 1725rpm.
Are you going to mount the motor behind the grinder ,away from grinder dust etc ?
I have been thinking of remounting my grinders ( two on a portable steel bench) and I saw a site where a guy has hung his grinders up on a wall. the motors are above the grinders,and the space below is clear, he uses them to polish guitar bodies and the free space prevents damage if the job gets caught , but it seemed like a great idea,especially where space is at a premium.
I have been thinking of remounting my grinders ( two on a portable steel bench) and I saw a site where a guy has hung his grinders up on a wall. the motors are above the grinders,and the space below is clear, he uses them to polish guitar bodies and the free space prevents damage if the job gets caught , but it seemed like a great idea,especially where space is at a premium.
