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I have a 14inch hare and forbes bandsaw. I think its one of the older Taiwanese models. It's actually a very accurate machine with a very nice setup, so I'd like to keep it but just want to be able to resaw thicker timbers. Can I replace the existing 3/4 horsepower motor with a 1 horsepower motor - or maybe even a 1.5 horsepower motor ? There is no riser.
cheers
Arron
Hi Arron,Quote:
Originally Posted by Arron
Changing out the original electric motor for a more powerful motor is something that many woodworkers consider doing with their woodworking machinery. Unfortunately, upgrading the motor to a more powerful one, does not often realise the benefits that the owner is hoping for.
It can be especially troublesome on a bandsaw, due to the layout of a bandsaw having the wheels well away from the vertical column axis where the majority of the strength lies. As you will no doubt have observed, you'll see 14 inch Woodwork Band Saws with electric motors ranging from 1/2 horsepower right up to 3 horsepower. Apart from the much more powerful motors, the primary difference with these more powerful bandsaws, is that they are much more strongly built than the low powered bandsaws. (A clue to this if you can't examine the machinery in person, is to look at the weights of the more powerful machines - the extra weight is not soley accounted for by the weight of the more powerful motor.)
The problem that you'll encounter when you change out the original motor for a more powerful unit, will be flexing and metal fatigue of the bandsaw frame and other components, when you try to use that extra power by doing some re-sawing.
Last year I looked at a second-hand 19inch wood bandsaw advertised on GumTree. A previous owner had upgraded the motor from 2 HP to 3 HP. I ended up not buying the machine because there were cracks around some of the welds on the vertical part of the frame - evidence that the frame was flexing under the load of sawing large pieces. The upper wheel also ran with a wobble, which I suspect was a result of the extra load also.
When a company designs and builds a piece of machinery commercially, they have to build to a price in order to make a profit. the ressult is often that the strencth of the compenents and teh structure are only just strong enough to do the job. Install a more powerful motor, and you start over stressing components of the saw.
So, if you do decide to upgrade the motor on your bandsaw to a more powerful one, bear in mind that you'll need to also strengthen the bandsaw frame to ensure that it remains stiff enough to handle the extra stress. You may also need to upgrade the wheel bearings to handle the extra stress. If your bandsaw already has cast iron wheels, they should be OK if they are fairly substantial. But some low powered bandsaws that have welded pressed steel wheels, that may not be strong enough, and may be difficult to strengthen whist keeping them running true and balanced.
We often grow attached to our favourite woodworking tools and machinery, and desire to keep them and make the better. Unfortunately, sometimes it can be more cost effective to buy a new or used item of mechinery that is stronger and more powerful, than to try to upgrade the one we already own.
Hope that info helps.
Regards,
Roy
Roy a great reply.
Covers all the bases.
Aaron what is your reason for wanting to put a bigger motor on.
Presumably you want to upgrade the motor because you want to be able to cut thicker pieces, faster without bogging the motor down?
If so then the motor is only aspect of the bandsaw that needs attention.
To cut faster on big pieces you first need a blade with fewer deeper teeth and so the first question I would ask is have you optimised the TPI of your blade?
To support a really low TPI blade with deep teeth the blade will need to be wider. A wider blade needs wider tyres and more tension than a narrower one and more tension needs a stronger frame. This is why they make different sizes of bandsaws to cater for these features.
A 14" BS can use up a blade up to about a ~4 TPI that is ~13 mm wide. Compare this to the deep gullet resaw blades used in 19"+ BS that are 32 mm wide and about 1TPI.
Just upgrading the motor and using the existing blades will often make little difference to the cutting speed because of the blade issue described above. However, if the motor is bogging down with low TPI blades in small pieces that is a sign that the motor is underpowered and a power upgrade is worth considering but you will need to at least double the power of the motor to notice any significant difference. Provided you do not push the system too hard, a decent bandsaw should be able to cope with this.
If the vertical part of a BS frame is cracked that has very little to do with the motor being too powerful but is a sign that either the BS was badly made in the first place or too large a blade requiring to great a blade tension has been placed on the frame. The greatest tension on the BS frame imposed by the motor is via the blade between the work pieces and the bearing/axle of the bottom or drive wheel, the blade after the drive wheel, and the top wheel and bearings, and upright part of the frame should not be affected. A more powerful motor will also place a greater strain on the table mounts so keep an eye on these to see they are not flexing under load.
Whatever you do, you will not get a stellar improvement in performance, even large powerful bandsaws still cut relatively slowly.
The other BIG headaches with motor upgrades on any machine is that straight swaps are a rare as true statements by politicians. The shaft, diameter, length and keyways need to match as well as the motor mountings also need to match. On some machines the motor has to physically fit in the provided space. If they don't then significant metal working is needed to adapt new motor to existing pulleys and mounts. In many cases these problems outweigh the benefits from any sort of motor upgrade. I recently spent a day adapting the shaft and mounting feet of a 1/3 HP motor from a washing machine to fit a bench top DP only to find the motor is not powerful enough to start the DP in the higher gears AARRGGGGHHC *&@%!$^&R.
I agree with BobL & Roy above. The biggest improvement you will get is with a decent blade. Suggest you look at the Resaw King with carbide teeth made by Laguna - their local agent sells them here in Brisbane.
There are people on this forum who use this blade with great success, getting hard timber veneers down to 1mm ( and 200mm high). You can get it in 3/4" or 1". Not cheap, but lots cheaper than a new motor.
Alternatively, have a chat with Henry Brothers - they are on the ball, easy to talk with, very helpful and have CT teeth blades too, which they resharpen locally.
thanks guys for the obvious time you put into these responses.
I cant follow this up much as recent surgery to arm limits typing.
Looks like not worth the trouble for dubious improvement and a good excuse to buy a new bandsaw.
cheers
Arron
Some years ago I swapped out a 3/4 hp motor for a 1.5 hp motor on a Carba-tec 14" bandsaw. They supplied the replacement motor. This certainly increased the cutting power insofar that that bandsaw did not bog down on harder woods, as it had before. The motor was not a lot larger and so fitted well.
The reason I eventually sold the bandsaw was that limitations in other areas were still present: the cast iron frame was not stiff enough for deep resawing, the guides were flimsy, etc..
Overall, the extra power was achieved and so the exercise was a success. Whether this is cost-effective for you, and whether it will be enough of a modification, is something only you can decide.
Regards from Perth
Derek
As Derek said it will improve things a bit but it is something you have to do the sums on to see if it is worth the expense. I did it on a machine like yours some years back. From 1/2 to 1hp. Quite a simple job replaceing the motor. It did improve the machine but I was still limited to a 6''cut. A year down the track I traded up to a 2 hp machine. I looked at the cost of the riser extension and yet a larger motor but opted for a new saw instead.
Regards
John
Definitely keep the 14" Bs if you have the space.Quote:
Originally Posted by Arron
The 14" size is a very good size for general work and small stuff and you can get very narrow blades for it that are not possible to use on a large BS.
Hope the surgery works out.
... nearly back on deck.
Anyway, I should have pointed out that I already have several old motors not being used - which is why I considered the idea. I don't think I would consider it if I had to buy a motor as well.
On this subject, rooting around in the cupboard with the motors, I find the one illustrated in the attached photo. It came off an old sand spear pump. It doesn't say on it how many hp it is, and I'm wondering if anyone can tell just by looking, or suggest some way of working it out. I've got a feeling I'm going to be told its just an old washing machine motor in which case it can go out, but I'd like to check first. Any ideas ?
If its 1 hp or maybe 1.5 then and the swapover looks easy then I might try it on the bandsaw. I anticipate a very small gain in performance, but that's all I expected anyway.
cheers
Arron
Attachment 321849
It's definitely not an old washing machine motor as very few washing machines used a totally enclosed motor like that. Usually their motors have no fan and lots of gaps for passive ventilation.Quote:
Originally Posted by Arron
If you lived in Perth I could measure the HP for you with my HP measuring rig!
That motor looks like the standard motor used on chinese wood and metal work machinery. I assume it has no nameplate but if it does take a photo of it and we'll see what we can work out from any info provided. There might also be some info under the black plastic cover of the capacitors.
I assume that it starts ok?
The next thing to do would be to measure the shaft of the motor. My guess is it will be a 19mm shaft which puts it in the ~1HP category.
This means you would need to bore out the BS pulley to fit it to the shaft but before you do that make sure that it will not weaken the BS pulley too much.
The you need to check what sort of shaft locking system it uses and if it is compatible withe the one on the BS.
Then how about the motor mounting system? - many BS motors used a front flange mount which is not easy to adapt to a foot mount as shown on that motor.