misc machine questions

[Will1987]

Hi heres some questions about power tools in my shop.

1. I bought a used band saw from this guy for 40 bucks and its fine but it doesn't have it's slide (or gauge, or fence) or whatever, and it needs one thrust bearing on top (thats a little wheel that spins against the back of the blade to keep it going against the pressure of the wood. I'll get the model number and all that but the thing looks like it could be from the late 60s early 70s and I was wondering what my best shot of finding replacement parts for it is?

2. I bought a used 4" jointer for 65 bucks, looks like it could also be from the psychedelic 60s or so and its blades have little chips in them. Its a craftsman. again, will I have to find new blades and where's the best place to look? also it needs a motor which shouldnt be too hard but if anybody knows where to find cheap electric motors (around 1/4 or half horsepower) thatd be cool.

3. I have a delta band saw from I beleive about 1990 or 91 bought off my neighbor and its a decent saw but I find I'm getting some blade burning. Is burning always caused by blade dullness or could there be some other cause?

4. I have a brand new random orbit sander thats pretty sweet but I find when I sand pine with it it leaves scribbly circular scratches in the wood. sometimes theyre not visible until I put stain on it. really frustrating. Can this be prevented somehow? I tried sanding by hand after I was done with the random orbit, but it doesnt always get rid of all of them and it seems to me it kinda defeats the purpose of using a power sander anyway. Any advice?

:D

Will

[Danno30008]

Hey Will:

I can offer some help with the sander...
Pine is a soft wood, and will show some scratches from your sander. So you might consider sanding with 220 grit on your sander and then hand sanding with a sanding block with the grain with the same 220 grit paper. I have found that if I want a really great finish, I have to do my finish sanding by hand. Then apply your stain and you should be good to go.
Good luck and keep us posted onyoru results.

Take care
Dan

[Cocobolove]

Will,

I'm not really sure what causes it, but even when I get a brand new blade for my bandsaw if I cut a hard wood like oak or maple I get some burn. So I'm guessing it's probably not from dullness. I just thought I was doing something wrong, and maybe I am, I'm glad I'm not the only one with this problem.

Matt

[Don]

Hey, Will. Slide and fences are available at WoodCraft most often. Check their site. Don't get too hung up on finding the exact replacement part for guide bearings, most of the time they are simply stock ball bearings, look to McMaster for a size that will work for you.

If you have a saw sharpening shop anywhere close they can regrind your knives. They can most likely hook you up with a new set as well. Again, if you have a decent grinder you can easily make a jig that will allow you to sharpen them yourself. Look at the Woodcraft online store for ideas there. Even if you can get all of the nicks out of the blades all you have to do is shift one blade over a tad in the head. (good trick). The 1/4 HP motor may be a little light, you'll want a least a 1/2 for light work, on up if you plan on facing the full width hardwood. Most 6" jointers are around 1 HP. Try Horror Freight for cheap motors.

Blade/wood burning is a simple issue. The blade is not sharp or clean. Or either you are binding when turning or the blade is being pinched. Burning wood is simply caused by friction. Sharp teeth that are shearing wood from the surface produce little heat. Dull, binding teeth produce a lot of heat. Once this heat is imparted to the blade tips, it's downhill from there. Small bandsaws do not have a lot of length of blade. I always say buy the largest bandsaw you can afford. I've worked on 36" bandsaws, they're like working with a laser beam and the blades last forever. A small 9, 12 and 14" bandsaw can have their blades ruined with a single cut, especially with blades they sell to civilians at the box stores. Never cut particle board if you want your blade to last. No painted wood, no old wood (dirty, sand), no green wood (with a small saw, teeth loading, pitch) no laminates, limit plywood to cabinet grade stuff. Why? Because glue is a tooth killer, construction material use cheaper woods and more glue - cabinet grade plywoods use better wood and less glue (even though there may be more plys) Solid wood is where bandsaws shine, soft woods such as pine can be pitchy and clog teeth, the medium softwood/hardwoods - poplar, basswood, fir, etc are a joy on blades and last a good long while. Hardwoods, oak, hickory, ash and other can dull a small/cheap blade quickly. Make sure you have the proper size blade for the material you are cutting, you want around 3-6 teeth in the material, (in general, and this is very important) too fine a blade for the material thickness will ruin one in a hurry. Bandsaws are finicky things, but tuned well with a good blade and fine material, they are a joy.

Scratches in wood from orbital sanding is simple as well. At some point you scratched the wood with a rougher grit on the sander. In some cases this can be the very same piece of paper, the paper started out sharp and quickly became dull. A cheap abrasive material like garnet is famous for this. Use an expensive paper and don't start with any rougher grit than you need to get the job done. As you go to finer paper, make sure the previous scratches are gone. It may feel smooth but there are still "cuts" in the wood from the previous paper. A good quality paper holds its "edge" better, i.e. the grit you started with is the grit you ended up with. That means that the succeeding paper has a better chance of removing the previous damage.

Cabinet scrapers are a joy to use when sharpened correctly and they do not leave scratched like this. Try some cabinet scrapers on a couple of projects then finish with a fine paper, you'll like it.

All the best, Don