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dr pepper
02-26-2013, 04:07 PM
I have a couple of bandsaws, one built from a kit of castings probably before I was alive.
Following a bit of use I need to do a bit of revamping.
The blade is guided at the back of the cutting table by a couple of ball bearings, LJ1/4 which I have got anew, however the sides of the blade are guided by simple pieces of hard leather, sort of a rub guide.
What could I replace these with, I dont think the machine needs or is worth the effort of fitting ball bearing guides in replacement, I need something 1/4" square section hard wearing.
I might try some delrin and see if that works, I have some brass keysteel but I think that'd have all the local dogs barking.

dfw5914
02-26-2013, 04:21 PM
I think the delrin will melt. I use HSS lathe tool stock, works good.
I've also seen micarta (aka phenolic) blocks used.

lynnl
02-26-2013, 06:02 PM
The older wood saw technology used what was called "cool blocks", which is a phenolic material impregnated with lubricating stuff. All the ones I've seen were on the order of 3/8" cross section. Can you modify the holders to accomodate that size? ....Not that I know 1/4" is not available.

A google search found this, wherein some are recommending using hard wood ,e.g maple. See here: http://lumberjocks.com/topics/15161

sasquatch
02-26-2013, 06:15 PM
I'd go with brass, or even Maple guides. Maple end grain is pretty tough, put a few drops of oil on them, they will last for a LONG time.

Duffy
02-26-2013, 06:31 PM
I use "Cool Blocks" as mentioned above. They can be adjusted to an interference fit to the blade, and the graphite lubricates. When the get a bit chewed up by the teeth, I just sand them square and reinstall them. The only problem with HSS blocks is that WHEN (not IF,) the blade gets a bit out of vertical alignment, and the teeth touch the blocks, kiss the blade goodby. You will loose the set of the teeth on one side or other and the blade then consistently cuts crooked, (while it scorches the wood!)

cameron
02-26-2013, 06:50 PM
Lignum vitae would make a good guide, probably a little better than hard maple.Maybe as good as cool blocks, and a lot easier to cut to shape. A pen blank should be enough for a set of guides.

Dave Cameron

sasquatch
02-26-2013, 07:48 PM
Agreed with the lignum vitae,, i think it is not only hard and dense, but somewhat oily.

dfw5914
02-26-2013, 09:17 PM
... The only problem with HSS blocks is that WHEN (not IF,) the blade gets a bit out of vertical alignment, and the teeth touch the blocks, kiss the blade goodby. You will loose the set of the teeth on one side or other and the blade then consistently cuts crooked, (while it scorches the wood!)

I have always set up the thrust bearing to maintain the side guides just behind the base of the gullets, I've never had a side guide come in contact with the blade teeth or the set portion of the blade. My bandsaw came factory equipped with plain steel guide blocks, the HSS works much better.

Stepside
02-26-2013, 09:40 PM
I have tried the "cool Blocks and wasn't impressed. I now use maple with some wax. When making the maple for the guides I made several feet of material the correct cross section. When the guides get worn I switch ends and run some more. When the second side gets worn I throw them away and cut new ones off the prepared stock. I tried the Ball Bearing guides and found them too noisy.

Circlip
02-27-2013, 03:54 AM
Burgess used Tufnol rod.

Regards Ian

SGW
02-27-2013, 06:45 AM
Go ahead and try the Delrin. I made a couple of Delrin blade guides for a friend about 3 months ago, and so far I've received no complaints.

http://i1338.photobucket.com/albums/o686/sasgw/IMG_2176_zpsfbefcaed.jpg

Abner
02-27-2013, 08:16 AM
UHMW? I used it for wearstrips

garagemark
02-27-2013, 09:01 AM
I use cool blocks on the bandsaw for wood. Been using the same set for over five years now. I get them here:

http://www.woodcraft.com/search2/search.aspx?query=COOL%20BLOCKS

12teethperinch
02-27-2013, 09:13 AM
Lots of suggestions so far. On my bandsaws of which there are three i made new guides from some mystery bronze from an old plaque. They have been on the saws for about 4 years. They havent needed to be adjustted in all that time and show no wear. The steel one on the large bandsaw were always needing attention. Wasnt impressed with the phenolic either.

dr pepper
02-27-2013, 03:01 PM
Lots of answers there then.
I think I have some round oilite bar somewhere that might be a good one, not sure how I'd get it down to 1/4 square though, its only around 3/8 to start with.
All that said my wife is a woodturner and says we have some maple scraps, so I think thats going to be the one to try, I'll plane down some pieces to 1/4, or rather I'll ask the mrs too, I hate woodwork, sawdust gets up yer sleeves.

John Stevenson
02-27-2013, 04:44 PM
I have lumps of ebony on mine, only because it was free. Tufnol is good

sasquatch
02-27-2013, 04:48 PM
Maple is "Old School" stuff, been used for guides for over a century! Works great.

A number of machines also ran in oil soaked maple bearings , not at the high RPM's of machines today, but they ran for decades.

Stepside
02-27-2013, 07:11 PM
In the 1950's we "rebuilt" my mothers wringer washing machine. The bearings for the wringer were oil soaked Maple. There was no wear on the roller shafts, so it was plug and play with the new factory blocks.

dr pepper
02-28-2013, 09:20 AM
Maple bearings, now theres a thing.
I have replaced babbit bearings before, or should I say repoured, which seems to be a rare thing these days, but I've never come accross wood bearings except for on the canal they use greenwood bearings for quoin bearings on lock gates.

Dunc
02-28-2013, 10:54 AM
Found ceramic guides...
http://www.abetterblade.com/product_p/guides.htm

Never used them, just saying another choice

Rosco-P
02-28-2013, 11:27 AM
In the 1950's we "rebuilt" my mothers wringer washing machine. The bearings for the wringer were oil soaked Maple. There was no wear on the roller shafts, so it was plug and play with the new factory blocks.

Maple pillow blocks were once common on the shafts of paddle wheel type aerators used in aquaculture ponds. Usually the wood block had a zerk fitting so a little grease could be squirted in, now and then.

Duffy
02-28-2013, 12:03 PM
Lignum vitea was the bearing material of choice for virtually ALL underwater bearings; turbines and propellor shafts as large as they were made (RMS Queen Mary?) Unfortunately, it is almost wiped out by overharvesting. It was also used for ships pulley blocks (the sheaves,), bowls and carver's mallet heads.

Paul Alciatore
02-28-2013, 01:01 PM
I have not seen a saw with solid guides so I must ask how are HSS guides mounted? I mean, it would be difficult to drill holes in it so is it clamped or glued in or what?



I have always set up the thrust bearing to maintain the side guides just behind the base of the gullets, I've never had a side guide come in contact with the blade teeth or the set portion of the blade. My bandsaw came factory equipped with plain steel guide blocks, the HSS works much better.

lynnl
02-28-2013, 02:40 PM
When we say "oil soaked maple" (e.g. bearings), are we talking about a process that literally penetrates and permeates the pores with oil throughout? ...something like pressure treated southern yellow pine, or like the oil embedded in oilite bearings? Or was this just a surface treatment?

bosox
02-28-2013, 04:42 PM
All I know is carbide or ceramic blade guides. :rolleyes:

Duffy
02-28-2013, 06:53 PM
Re Oil-soaked maple. Similar to oil-soaked, I have installed WAXED maple bearing blocks in wringer assemblies. These appeared to have been soaked in hot parafin wax, and I imagine that the same would apply for oil soaking. Waxed maple was apparently preferred to oiled maple because the wax is somewhat less soluble in soapy water and the blocks lasted longer.
I cant say whether the wax penetrated completely, since I never saw a block split open.

dfw5914
02-28-2013, 10:01 PM
I have not seen a saw with solid guides so I must ask how are HSS guides mounted? I mean, it would be difficult to drill holes in it so is it clamped or glued in or what?

When I did this it was because the original soft steel guides had worn to the point that I could no longer use them.
I was in a hurry so I just grabbed a lathe tool (because it fit) out of the junk box, chopped it in two with an abrasive wheel, and stuck 'em in there (fully intending on getting some cool blocks or something similar when I got the chance).
It's been at least a year and I have not needed to adjust them, so I guess they get to keep the job. One of these days I'll cut off the shaped end.

http://i112.photobucket.com/albums/n188/pmhurco/9c2c9ed0-a3a7-4d7b-995b-b67cd0e496b6_zps384e14ae.jpg

http://i112.photobucket.com/albums/n188/pmhurco/c9b7e3a5-a108-4ebe-98c1-830372610e97_zpsec23fc86.jpg

sasquatch
02-28-2013, 10:14 PM
Re: Wooden (Maple) guides and bearings:

Some were soaked in heated oil, some had a oil hole drilled through them, fitted with similar to "Gitts " oilers, and some had a hole with a "Zerk" fitting. And i bet a few also had "Oil Grooves cut into the inside like babbitt bearings.
Oiled hardwood bearings will run for a long time if occaisonal lubing is looked after. Maple or other hardwood guides should last a long time as you are using the "End Grain". They lasted a LONG time on old cast iron bandsaws from the early 1900's.

dr pepper
03-01-2013, 05:40 AM
Said wife turned some 1/4 maple for me and insisted round would fit and be ok, and it is works fine with round, the ends being sanded on an angle means they dont try and spin round in the holder (my saw has them positioned at an angle, not quite 45), and 2 1/2 inches of lenght means I'll get some wear out of them.
A spare pair is sat at the back of the 'shop soaking in hydraulic oil.
If for some reason this doesnt work out I have an old turning tool at the ready as per dfw's.
Oh and I changed the ball bearings behind the blade for ones with rubber seals.