Burnt ends!

[Bob Ellis]

I've been making pens and selling them to raise money for a local charity for about 18 months. My pens are all turned from wood rather than acrylics or anything else. Although I am quite self-critical, I am pleased with the quality of the pens I have been producing over the last few months and customer response has been very favourable. However, I have a problem when barrel trimming some of the lighter woods. The trimmer tends to burn and discolour the ends of the pen blanks.

My set-up is a small Sherline 5000 lathe with the blanks mounted in a four-jaw chuck and a barrel trimmer mounted in the tailstock. I have tried running the lathe at various speeds, the maximum possible being 2,800 rpm. Around 2/3 to 3/4 speed seems to cause the least damage, but I am still getting burnt ends on lighter woods. What am I doing wrong?

 

[Bigblackdog]

i would suggest that there are 2 factors- speed and sharpness of the trimmer. Using a diamond credid card sharpener made a huge difference on mine.

the tool is rubbing on the end of the blank causing friction- the higher the speed the more generated in a given time and ultimately burning. If it is blunt instead of cutting, it is causing more friction, same result.

You will get the same if you use a sander and a fine grit paper.

 

[paulm]

The problem is that the barrel trimmer isn't sharp Bob.

 

[Bob Ellis]

The problem is that the barrel trimmer isn't sharp Bob.

Thanks, guys. I wondered about that and tried using a diamond credit card sharpener, but it sounds as though I didn't sharpen the trimmer sufficiently. I shall have another go. I have some thuya burr blanks ready for trimming so I shall see whether further sharpening improves matters and report back on my progress.

 

[Phil Dart]

If you are not a regular "head sharpener" it's entirely possible your problem is caused by using a blunt trimmer head. Give it a good sharpen, slow it down to maybe 600 to 800 rpm, and try again to see if the problem goes away.

A trimmer head is a cutting tool like any other, and needs to be kept sharp in the first instance and used at a speed appropriate to the diameter of the cut in the second. You wouldn't get away with a blunt three quarter inch drill at 1800rpm, and you can't expect your barrel trimmer to do a good job under those conditions either.

I hope that helps.

 

[Phil Dart]

Ooop. Lots of posts crossed whilst I was busy typing.

 

[Grump]

Same advise as above Billy, I would definitely say it's not cutting but rubbing and you shouldn't need a fast spin either.

 

[Jim]

I have some thuya burr blanks ready for trimming so I shall see whether further sharpening improves matters and report back on my progress.

Be careful with the Thuya Bob, even with a very sharp trimmer Thuya is easily torn when trimming ..

 

[wm460]

I chucked my end trimmer and made this, I am using 120 grit sand paper.

 

[Penpal]

I have the same basic experiences end trimming and like Mark chucked the end trimmer years ago in favour of disk sanding with great success.

Peter.

 

[Baldy]

I chucked my end trimmer and made this, I am using 120 grit sand paper.

I like look of this for a set up.. next to do job in shed..[emoji106] [emoji106]

 

[Bob Ellis]

I have ze good news and ze bad news!

Good news: Having sharpened the offending barrel trimmer again, I realised that I was not sharpening it enough. I used it yesterday on some Pau Rosa blanks and some Lignum Vitae blanks without any burning.

Bad news: Following the warning in an earlier post about the risk of tearing Thuya Burr, even with a sharpened barrel trimmer, I decided to square off the ends using my Pro Edge. Not a good idea! While it squared off the ends nicely, it has clogged the belt badly. Any advice on cleaning the belt or will I need to bite the bullet and buy another one?

 

[Phil Dart]

Yes, you can bur a rubberised stick specially for the purpose. I don't know what you might call it officially, abrasive cleaning stick maybe, but Axminster sell them and I'm sure a quick google search will reveal plenty.

I have also heard tell that a piece of rubber hose pipe will do the job just as well, but having a stick, I've never tried the hose.

 

[wm460]

Thats easy, you know all those tube of silastic, no more gap etc that go hard in the tube, cut the plastic cover off and use the inards.

Doesn't work as good as this but does the job.

https://www.google.com/url?sa=t&rct...0aI1iB7BiYLjHcFfSz18Ow&bvm=bv.102022582,d.dGY

 

[Penpal]

I go to markets and buy the largest sandal thongs on special they do the job wonderfully well.

Peter.

 

[Twister]

i have a proedge setup for my blanks

i am lazy and just change belt when it stops working

Steve

 

[Woody]

Same here I dumped my trimmer years ago and use the disk sander and it never fails but I must add it has to be set up square

 

[Terry Q]

If you have clogged your belt so badly that the rubber stick won't clean it remove the belt and soak it a couple hours in water and dish washing soap. I use Dawn. Then a wire brush should remove most of the residue. Be sure to let the belt to fully dry before recounting. The trick to using the sanding stick is use early and often.

 

[Grump]

I just hold a wire brush against it and switch on, a few sparks later nice clean belt init?

 

[Anthraquinone]

Provided the belt is not totally clogged (it may work even then) the cheapest solution I have found is a scrunched up Tesco etc carrier bag. Just make sure there are no loose bits sticking out. This also works on my sanding disks.

AQ