Thread: Machining sawn timber

Most motors are either 1440 or 2880 rpm, therefore you should be able to make an educated guess as to which one you have, (I am betting on a 1440), by tracing the gearing/drive system and calculating the ratios. If you have a power supply available, power the motor up and put a tachometer on it. If all else fails, take the motor to a motor rewinding establishment and they should be able to tell you the rpm's.
Not being picky, but do you realise that there is no such beast as a two phase motor, (many do not), they are either single phase - two wires and earth, or 3 phase - three wires and earth.
Why do you want pto drive, are you in a remote area? Have you considered the need for dust extraction, (if you don't have electricity then you will need an alternative energy source).

Thanks for reply Karl
Single phase ! Doh! Get caught every time
Matters little as we are off grid and no desire to run large gennie
Will do the numbers on pulley ratios
Interestingly have discovered the drive rollers are independently driven so more calculations & engineering will be necessary
Did receive a cyclone blower with unit so will give some thought to that aspect as well
May well be suited to old style overhead shaft drive...

PTO drive might be a little tricky. Speed is normally 540rpm, but some tractors have an optional 1000rpm shaft also.

Neither of these would be fast enough even if the original motor was 4-pole (approx 1440rpm). You would need to increase the drive pulley to three times the size for a 540 PTO and half as big again if you have a 1000 PTO. If the motor is a 2-pole (approx 2850rpm) the drive pulleys would have to be six times the size (540rpm) or three times the size (1000rpm). I hope I have those calcs correct, but hopefully you will get the gist of what we are talking about.

You could conceiveably run a small independent motor, such as a firefighter size, for the drive pulleys as they will probably be on the other side of your machine.

Just be aware that tractors are primarily made to travel (I'm good at stating the obvious) and running them for long periods, reving hard to achieve PTO speed while stationary may not be in the best interest of the tractor.

A final thought is that the thicknesser itself will need to be very firmly secured to the ground (preferably a solid foundation).

Regards
Paul

Most thicknessers cutterheads spin at 4,700 rpm to 6,000 rpm the motor usually 2800 rpm
runs about a 2 to 1 pulley reduction via v belts.

I would opt for a small petrol motor and double v belt drive.
Much cheaper than rebuilding a tractor engine and you can work out your revs with the pulley diameter, so your thicknesser works at it's best speed.

I have seen one very old thicknesser set up this way and it worked very well. It was powered by a 5hp, Briggs and Stratton motor.

Paul.

Not sure if you realise this but thicknessing is a secondary process following jointing to get a flat face and a straight edge square to the face.

A Thicky will bring the side opposite the jointed face parallel to the face, but will mirror any defects like bows or twists. Jointers have fences and long tables to optimise flatness and straightness, while thickies have a short bed to accurately follow the reference face.

You might need to look for a jointer as well. I would be considering using a stationary engine for both if you wish to stay off grid.

Thanks for everyones suggestions...they are greatly appreciated.
Another problem I have encountered is calculating the feed roller speed it has a 3 speed box with a pulley on the shaft but I have no idea the size of the pulley on the electric motor I don't think the motor I got with it is the original.....any ideas
When I get home I will post some photos which may make it easier to explain
What sizes do jointers come in and do they have power feeds on the larger ones?
I was hoping that as the majority of cut timber is fairly straight the thicky may do a reasonable job...understand it will not straighten

Thicknesser vs jointer - depends what you're wanting to achieve.
Personally I only have a thicknesser/moulder, its not heavy duty like yours, but it only gets small time usage.

Originally Posted by woodywpecker

Thanks for everyones suggestions...they are greatly appreciated.
Another problem I have encountered is calculating the feed roller speed it has a 3 speed box with a pulley on the shaft but I have no idea the size of the pulley on the electric motor I don't think the motor I got with it is the original.....any ideas
When I get home I will post some photos which may make it easier to explain
What sizes do jointers come in and do they have power feeds on the larger ones?
I was hoping that as the majority of cut timber is fairly straight the thicky may do a reasonable job...understand it will not straighten

Woodywpecker

To get some idea about jointers, have a look at the Carbatec website. You will see quite a range there. You could also do a search on ebay as quite often larger three phase machines come up. Again you could attach an independent motor to one of these.

I have two jointers. One is really small with a 1200mm table length and a 150mm cutter head. The other is still only 1800mm long but has a monsterous 600mm cuttting width!

However, the length of table is more important and width will commonly be 200mm to 300mm typically.

Most jointers I have seen are manual feed, but an automatic feeder can be attached to the table top if you wish.

Just returning to the thicknesser speeds, there will be an optimum cutter speed, but cutter heads vary in diameter so it is difficult to say what speed any individual machine should spin at withou knowing that information. As with circular saws it is the tip speed that is important.

Regards
Paul