"Kickback" when using a pin router with downcut spiral? - Router Forums
 1Likes
Reply
 
LinkBack Thread Tools Display Modes
post #1 of 15 (permalink) Old 10-13-2015, 08:55 PM Thread Starter
Registered User
 
Join Date: Oct 2015
Country: United States
First Name: N/a
Posts: 11
 
Default "Kickback" when using a pin router with downcut spiral?

Hello all. First post, howdy!

I recently made a pin router attachment for my cheap harbor freight router table and just got around to testing it out on some patterns. Almost immediately I was greeted with some kickback. It didn't throw the piece accross the room or anything but it kinda routed inside where the pattern shouldn't have allowed it to somehow in a quick jerking fashion. I am using a brand new whiteside downcut 1/4" spiral bit on 1/2" birch ply, doing about a 1/4" pass.

On one of the pics you can see the "kickbacks" on opposite sides of the wood because I attached the pattern to the other side of the wood to experiment again with a first pass after the first test had issues.

Im pretty surprised at this, I had previously done similar patterns but using a pattern bushing hogging the entire 1/2" plywood in one pass without this happening. At that time I was using a 1/4" upcut spiral though. I thought I would be on easy street with the pin attachment and taking 1/4" passes.

On my second try on the other side of the wood I was able to get one side of the pattern to go without a hitch but the other 3 sides still had an issue. This is happening on a very slight concave curve on the pattern mostly which all 4 sides of the pattern have. It's really not a big curve at all.

I am somewhat a rookie at this router table madness. Do any experienced folk have any input into this issue? Is it no bueno to use a downcut spiral bit for pin routing, dadgum it makes a smooth cut when it's not gouging the heck out of the wood. Should I be doing a full depth pass? Maybe it's my technique or something? This gouging can't be good for the bit either, right? I really appreciate any insight, thanks!
Attached Thumbnails
Click image for larger version

Name:	20151013_193403_resized.jpg
Views:	150
Size:	588.3 KB
ID:	157081  

Click image for larger version

Name:	20151013_193343_resized.jpg
Views:	130
Size:	610.8 KB
ID:	157089  

Click image for larger version

Name:	20151013_193245_resized.jpg
Views:	132
Size:	512.1 KB
ID:	157097  

dcdc is offline  
Sponsored Links
Advertisement
 
post #2 of 15 (permalink) Old 10-13-2015, 09:42 PM
Official Greeter
 
old55's Avatar
 
Join Date: Aug 2013
Country: Australia
First Name: Ross
Posts: 6,581
 
Default

Welcome to the forum.

Ross,
Rockhampton, Queensland, Australia


Enjoy the knowledge of others that can be found within.

‘Members are requested to add a first name in their profile as we are a very friendly bunch here'.
old55 is online now  
post #3 of 15 (permalink) Old 10-13-2015, 10:37 PM
Moderation Team
 
Cherryville Chuck's Avatar
 
Join Date: Sep 2010
Country: Canada
First Name: Charles
Posts: 15,069
 
Default

Welcome dcdc. How stiff is the pin. If it can move a bit it may allow the bit to grab the wood. The down cut is also pushing the wood up so I would add some feather boards or at least some guides attached to the fence that would prevent the workpiece from lifting up.
ksidwy likes this.

Someone I consider a master woodworker once told me that a master woodworker is not someone who never makes mistakes. He is someone who is able to cover them up so that no one can tell.
Cherryville Chuck is offline  
Sponsored Links
Advertisement
 
post #4 of 15 (permalink) Old 10-14-2015, 12:25 AM Thread Starter
Registered User
 
Join Date: Oct 2015
Country: United States
First Name: N/a
Posts: 11
 
Default

The pin seems very stiff, and I am not pressing the template against it very hard. I think you may be on to something about the featherboard/hold down for the workpiece and template. I just hadn't seen that on any of the other pin router pics and vids I had seen. Maybe the downcut requires this though. I think I may add 2x 1/4" rods parallel with the table at the height of the piece/template combo, one on each side of the bit. It would be nice to make it adjustable in height but I'm not sure how that could be done with my janky setup and resources hehe. I will mainly be routing all the same plywood though so one height will do for now.
dcdc is offline  
post #5 of 15 (permalink) Old 10-14-2015, 12:41 AM
Forum Contributor
 
Herb Stoops's Avatar
 
Join Date: Nov 2014
Country: United States
First Name: Herb
Posts: 7,401
 
Default

WHen I pin route I don't use a fence. the pin routing I do is for curved surfaces and if the part gets trapped between the fence and the pin and the template wants to turn it can cause a binding and force the bit into the unwanted areas. Your set up can trap the piece between the fence and the pin and the bit . My pin arm is mounted independent of the fence.

Could be a possibility.
Herb
Herb Stoops is offline  
post #6 of 15 (permalink) Old 10-14-2015, 12:42 AM Thread Starter
Registered User
 
Join Date: Oct 2015
Country: United States
First Name: N/a
Posts: 11
 
Default

hah, I guess it could be adjustable in height by just raising the whole pin router attachment thingy up since it is just clamped to the crappy stock fence of the harbor freight table. Still couldnt go down, but 50% is 100% better than 0%...or something.
dcdc is offline  
post #7 of 15 (permalink) Old 10-14-2015, 12:43 AM Thread Starter
Registered User
 
Join Date: Oct 2015
Country: United States
First Name: N/a
Posts: 11
 
Default

Well i don't use the fence for any...fencing. It just happens to be what the pin attachment is mounted to for convenience. Nothing ever comes into contact with it.
dcdc is offline  
post #8 of 15 (permalink) Old 10-14-2015, 02:02 AM
Forum Contributor
 
Stick486's Avatar
 
Join Date: Jan 2013
Country: United States
First Name: Stick
Posts: 25,277
 
Default

go w/ a bearing guided flush trim bit...

This would have been the week that I'd have finished chewing thru the restraints...
If only new layers hadn't been added....

Stick....
Forget the primal scream, just ROAR!!!
"SNORK Mountain Congressional Library and Taxidermy”
Stick486 is online now  
post #9 of 15 (permalink) Old 10-14-2015, 02:16 AM Thread Starter
Registered User
 
Join Date: Oct 2015
Country: United States
First Name: N/a
Posts: 11
 
Default

Well then I wouldn't be able to do inside work like shapes for resin inlays. Plus it would make the whole pin system a waste of time. And from what I understand the 1/4 inch bearings don't last very long besides being unavailable locally, and it has to be 1/4 inch because of the shape of some of the pattern, not seen in the pics.
dcdc is offline  
post #10 of 15 (permalink) Old 10-14-2015, 02:24 AM Thread Starter
Registered User
 
Join Date: Oct 2015
Country: United States
First Name: N/a
Posts: 11
 
Default

Do you guys think 2x 1/4" passes is appropriate for 1/2" birch ply with this 1/4" down spiral bit? Maybe I should do it in 3 passes instead? I would really like to keep the number of passes down, but I don't currently have a bandsaw to cut the stock within 1/16 to do one pass.
dcdc is offline  
Reply

Quick Reply
Message:
Options

Register Now



In order to be able to post messages on the Router Forums forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.

User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in











Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page
Display Modes
Linear Mode Linear Mode



Similar Threads
Thread Thread Starter Forum Replies Last Post
Sort Members by City or Zip RJM60 Site Help and Suggestions 56 03-13-2014 06:40 PM
Downcut spiral bit in a router table cagenuts Router Bits - Types and Usage 5 08-23-2010 03:44 AM
Router Table Pin Router Tim in Delaware Table-mounted Routing 7 03-08-2010 03:55 AM
overarm pin router 46_trap Table-mounted Routing 3 02-10-2010 03:27 PM
building a Pin Router dane5547 General Routing 36 08-13-2009 03:58 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome