Bandsaw Guide Blocks

billmayo · Post by **billmayo** » Wed Dec 04, 2013 2:58 am

I was cutting on my bandsaw some strips off a impact-Resistant UHMW Polyethylene Sheet, White, 3/4" Thick, 6" X 6" for making jigsaw yoke blocks when a new thought occurred to me. I have made a batch of these yoke blocks years ago but have sold almost all of them so needed more now. I had many small pieces left over from this first batch that I used when making jigs when I had two surfaces that had to slide. I also used thin pieces under sliding tables I made for several table saws. It is a very slipply and a tough wearing material.

So this thought occurred to me, this material might make great guide blocks for the bandsaw. It seems to have the same advantage as the cool blocks as it does not damage the bandsaw blade teeth cutting it. Cost would be very reasonable. I will try to make a couple sets of guide blocks and see what happens when I use them. Does anyone know why this material should not work or that it could work as guide blocks? I could find no examples of this material being used for guide blocks.

Ed in Tampa · Post by **Ed in Tampa** » Wed Dec 04, 2013 11:03 am

I would think the friction of the blade would melt them.
If you make a set cut a few circles out and see if the melted by having the blade run against them.

terrydowning · Post by **terrydowning** » Wed Dec 04, 2013 12:10 pm

I was thinking the same thing Ed.

Heat from friction would be an issue.

charlese · Post by **charlese** » Wed Dec 04, 2013 1:01 pm

Agree with the last two posts! However it would be interesting to see the results of using the pieces for guide blocks.

I know a router bit will leave a extended burr. Don't think this would be especially harmful on bandsaw blades but a decreased rubbing surface would make for wobble.

Come to think bout it - don't know if it is actually melting that causes the burr from routing. Only a lack of a clean cut????

joshh · Post by **joshh** » Wed Dec 04, 2013 1:08 pm

Found this:

"The weak bonding between olefin molecules allows local thermal excitations to disrupt the crystalline order of a given chain piece-by-piece, giving it much poorer heat resistance than other high-strength fibers. Its melting point is around 130 to 136 °C (266 to 277 °F) and, according to DSM, it is not advisable to use UHMWPE fibers at temperatures exceeding 80 to 100 °C (176 to 212 °F) for long periods of time. It becomes brittle at temperatures below −150 °C (−240 °F)."

Anyone have a laser temp gauge? We could see if the temp exceeds 176 degrees during normal use.

billmayo · Post by **billmayo** » Wed Dec 04, 2013 2:59 pm

[quote="joshh"]Found this:

"The weak bonding between olefin molecules allows local thermal excitations to disrupt the crystalline order of a given chain piece-by-piece, giving it much poorer heat resistance than other high-strength fibers. Its melting point is around 130 to 136 °C (266 to 277 °F) and, according to DSM, it is not advisable to use UHMWPE fibers at temperatures exceeding 80 to 100 °C (176 to 212 °F) for long periods of time. It becomes brittle at temperatures below &#8722]

Thanks for all the comments. Temp was not one of the things I thought about. I know the orange tires can deform from a too hot bandsaw blade so you have a very valid point. I have a lazer temp meter that I use to monitor headstock temp when checking out different brands of bearings. OK, it is on my bucket list to make a couple and see what happens. I do not believe I could be succesful with this idea. Oh, well. I would guess the oil in the jig saw body is keeps the temp well within reason is why this material has functioned well for the yoke blocks.

Does anyone know where I could buy material to make cool blocks? Google did not give me any resources where I can buy it. I was able to find a material called MP325 that would seems to what I wanted but no way to buy it.

greitz · Post by **greitz** » Wed Dec 04, 2013 3:16 pm

Bill- Are you no longer recommending your ceramic bandsaw blade guide blocks?

Gary

JPG · Post by **JPG** » Wed Dec 04, 2013 3:39 pm

Housewares - cutting board.

Gene Howe · Post by **Gene Howe** » Wed Dec 04, 2013 4:24 pm

Bill, I use oak. After dimensioning, I soak the sticks in used motor oil for a few days. I suppose most hardwoods would serve the purpose, too.
Been doing this for many years. Works fine for me.

billmayo · Post by **billmayo** » Wed Dec 04, 2013 6:42 pm

greitz wrote:Bill- Are you no longer recommending your ceramic bandsaw blade guide blocks?

Gary

I believe I am still the only seller of ceramic bandsaw guide blocks for the Shopsmith and I still have some available. I do not recommend or suggest you use these ceramic guide blocks on bandsaw blades sizes smaller than 1/4". Even the 1/4" saw blade may be too small. The ceramic blocks will remove any set on the teeth and dull them if they come in contact. They do not show wear and last forever. The ceramic blocks work really well for the 1/2" & 5/8" blades. I believe you must have cool blocks for the 3/16", 1/8" & 1/16" blades so my thoughts were for these size blades.

OK, soapbox time again. I am having really great success since I started using two ABEC7 rated bearings for each of the upper and lower blade guides. This helps relieve some of the side pressure on the blade guide blocks when cutting circles. Because these bearings have a more rounded shoulder, the blade tracks a little deeper between the bearings (no shim was needed) and works like the Carter Stablizer ($80). So far, no squealing or other noise from these bearings but will continue to check with more operating hours. Contact me if interested.