LumberJocks

How to prevent a screw thread from detaching?

  • Advertise with us

« back to Power Tools, Hardware and Accessories forum

Forum topic by bluekingfisher posted 09-10-2014 10:35 AM 942 views 1 time favorited 6 replies Add to Favorites Watch
View bluekingfisher's profile

bluekingfisher

1246 posts in 2445 days


09-10-2014 10:35 AM

I will soon be building a small bench top router table and intend to build an accurate fence for it.

I was looking at the micro adjuster manufactured by Woodpeckers http://www.carbideprocessors.com/micro- ... rs-micadj/

This accessory doesn’t seem too difficult to build although what I would appreciate assistance with is, what prevents the main turn screw from unthreading from the push block when you retract the handle?

On advancement of the fence the screw would naturally push the block against the fence, when retracting the fence, the anti clockwise turning of the handle will detwach the thread from the push block. What therefore keeps it in place for both advancement and retraction?

Any ideas?

Cheers

David

-- No one plans to fail, they just, just fail to plan


6 replies so far

View Roger's profile

Roger

19878 posts in 2269 days


#1 posted 09-10-2014 12:35 PM

That’s a gr8 question David. I’ll be following along to see what kind o answers are out there. My thoughts are 2 rods epoxied into the fence with a threaded rod in the middle, recessed and epoxied in the fence as well with the “adjuster”/bolt head or what ever on the back side. When you would crank the bolt/threaded rod, the whole fence would move evenly. (Similar to the lift mechanism of a homemade router lift. I can picture it in my head, but hard to explain.

-- Roger from KY. Work/Play/Travel Safe. Keep your dust collector fed. Kentuk55@yahoo.com

View ohtimberwolf's profile

ohtimberwolf

634 posts in 1817 days


#2 posted 09-10-2014 12:48 PM

Who ever makes these videos hasn’t a clue as to how to demonstrate a tool. But you may see what you need to know if you watch carefully and don’t miss a lick.

https://www.youtube.com/watch?v=-WeCmzPeqxE#t=16

-- Just a barn cat, now gone to cat heaven.

View HillbillyShooter's profile

HillbillyShooter

5811 posts in 1757 days


#3 posted 09-10-2014 01:14 PM

Although I can’t get your link to work, I suspect the answer lies in an arrangement where one screw/bolt is captured in a unthreaded hole with the head on the outside and a washer and locknut (or two nuts jamed together to lock) on the inner surface and which comprise the stationary block, and a second adjusting block that actually moves back and forth since the screw/bolt is threaded in the second block. The first/stationary block is permanently attached to the base of the main unit that slides back and forth to obtain a preliminary, rough adjustment; and, the second adjusting block slides on the main unit over a key like you used in your thin strip jig, to make the fine adjustment. I’ve used 10×32 screw/bolts for such mechanisms in the past because one complete revolution equals 1/32” adjustment. Confusing, but maybe this will give you some ideas.

-- John C. -- "Firearms are second only to the Constitution in importance; they are the peoples' liberty's teeth." George Washington

View bluekingfisher's profile

bluekingfisher

1246 posts in 2445 days


#4 posted 09-10-2014 01:24 PM

Ok fellas many thanks for responding.

Here is what I have since considered to be a possible answer.

Drill a hole into and through the push block the size or slightly larger than the threaded rod, then insert a tight fitting star washer over the end of the rod and before the push block so that when the rod is retarded it pulls the push block back and not unthread itself??

Perhaps another version would be to drill a small hole through the end of the rod and insert a retaining or split pin, again to prevent the unscrewing action. I guess I would also have to recess a penny washer into the face of the push block to prevent the pin or small star washer from srcubbing the face of the block when the rod is cranked back.

To cover the end of the rod were it extends beyond the push block, as you mention Roger, laminate a piece of wood over the end to create an uninterupted face of the push block again..

i don’t know whether it will work but it seems logical enough now.

Thanks guys.

David

-- No one plans to fail, they just, just fail to plan

View bluekingfisher's profile

bluekingfisher

1246 posts in 2445 days


#5 posted 09-10-2014 01:34 PM

Hi John,

We must have been typing at the same time, you however must have pulled the post button first.

As I sit here and type this, I think I may have an old acme screw salvaged from a workmate type bench. I think there may be a cam on the end of it too, which I could possible utiliise??

I may also have a kitchen cabinet leveller adjuste in my hardware bin, left over from the kitchen remodel, the right angled metal bracket type with the threaded rod with the allen key adjustment slot at the end of the rod.

Thanks again boys, now I have an idea of how it works I will be able to manufacture something I’m sure.

David

-- No one plans to fail, they just, just fail to plan

View Roger's profile

Roger

19878 posts in 2269 days


#6 posted 09-11-2014 12:52 PM

ohtimberwolf’s link is exactly what I was picturing in my head. Of course Woodpeckers is high quality and big $$, but, there has been many LJ’s here that have made jigs and such of this same nature that wouldn’t break your wallet. Good luck David.

-- Roger from KY. Work/Play/Travel Safe. Keep your dust collector fed. Kentuk55@yahoo.com

Have your say...

You must be signed in to reply.

DISCLAIMER: Any posts on LJ are posted by individuals acting in their own right and do not necessarily reflect the views of LJ. LJ will not be held liable for the actions of any user.

Latest Projects | Latest Blog Entries | Latest Forum Topics

HomeRefurbers.com