Oops

Went to a customer last week that had made a very big oops. Generally speaking, wide belt sanders are pretty hard to mechanically damage. When things do go wrong, and damage occurs, there is usually a conglomeration of events that had to happen in a specific order to cause the negative end result.

One big exception to this is height adjustment. While it is always safe to open the machine, care must be taken when closing. Especially after some kind of evolution has taken place such as maintenance, cleaning, or testing. A great habit to form is to check the inside of the machine before closing it, especially if the feed belt is not running.

Some machines have a sensing roller or rollers in the front of the machine that prevent the machine from automatically closing to the preset height unless the feed belt travels a certain distance to ensure that there is no part in the machine. When a part, or tool is placed into the machine like when calibration is checked these sensing rollers are taken out of the equation. The machine will close to whatever value is in the controller as soon as the machine is switched on.

This will crush the tool or part and push the sanding head up. Damage can range from a chunk taken out of a rubber roll, to wrecking the graphite layer of a platen, to bending of a segmented pad. Worst case scenario is that the head frame itself and the frame it is bolted to get bent and/or cracked.

This is what unfortunately happened to my customer last week. Very expensive lesson.

Brush Sanding

Hello,

Hope everyone's week went well. I had a very interesting week dealing with 2 brush sanding applications. Both companies had just recently bought a brush sanders.

They both brought me in to get the machines to work for their application. This application turned out to be the same one. They are both making cabinet doors from MDF, brush sanding them, and then pressing them.

One company actually wants to use the same brush sander to sand the MDF, "denib" the glue after it is applied, and then remove the glue overspray from the back of the door. The other owns a Gottschild machine for removing the glue and doesn't need or doesn't want to denib the glue.

The problem both are having is that they thought they couldn't get the tool marks out from their router. One was a KOMO, and one an Onsrud. Coincidentally, they both use a brand of MDF from Flakeboard out of Canada called Superior Plus.

What I saw from the product though was not tool marks, but rather core tear out from the tooling. There is no way a brush sander can remove these marks without obliterating the corners and edges. See picture:

This is a tooling issue, not a sanding issue. Our next step here is to bring in a router tooling expert to work with me on getting perfect product to their membrane presses. The most important thing to remember about a brush sander is that it is for scratch pattern, not stock removal.

Please check out the video from my friends at Flex Trim on my Facebook page. The link is on the right.

Please let me know if there is anything I can help you with.

Have a great week.

Miscellaneous Links

Here are a few articles I wrote, some I'm quoted in and a webinar I did all on Brush Sanding. Just trying to get them all in one spot.

Here is a general brush sanding article from ISW Online: http://tinyurl.com/mtvpy5

Here is a webinar that I authored and gave last year. I will be giving another on Brush Sanding after the Las Vegas show. Sometime in the beginning of August. Please let me know if you are interested in attending.

Please look for the article 06/08. Thanks.

http://tinyurl.com/n96j4k

5 Piece Doors - Part 1

Hello everyone. Thanks for visiting today. I'm posting a short pamphlet on finishing 5-piece doors today. I have this in PDF format if anyone wants it emailed to them. I made them JPG's here for ease of downloading and viewing.

Please let me know what you think about these on the comments below or feel free to Twitter me @SandingMan. Happy 4th of July everyone.

This is continued on the next post.

5 Piece Doors - Part 2

Again, please let me know if you have any comments.