# I need a left-hand thread screw... **URL:** \ **Category:** Factual Questions\ **Created:** [June 18, 2009, 1:37am UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132 "2009-06-18T01:37:33Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)\ **Post date:** [June 18, 2009, 1:37am UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/1 "2009-06-18T01:37:33Z")
…no, that’s not a double entendre. Here’s the deal: I have a gas poweed Homelite weed-whacker and the shaft the spool bolts to snapped halfway down it’s length. There is still enough thread inside the shaft to bolt the spool to it…If I only had a screw twice as long as what I have. No hardware store near me has lef hand threaded anything, and none of the lawnmower/leafblower/weedwhacker repair shops around me have the correct thread. BTW…the reason this has a left-hand-thread is, becawse of the direction the spool rotates, if it had a regular right-hand thread screw, would constantly unscrew itself from the shaft. ---
**Author:** ![Chief\_Pedant](https://avatars.discourse-cdn.com/v4/letter/c/a6a055/32.png) [@Chief\_Pedant](https://boards.straightdope.com/u/Chief_Pedant)\ **Post date:** [June 18, 2009, 1:47am UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/2 "2009-06-18T01:47:05Z")
> [@Enola\_Straight](#): > > …no, that’s not a double entendre. > > Here’s the deal: I have a gas poweed Homelite weed-whacker and the shaft the spool bolts to snapped halfway down it’s length. There is still enough thread inside the shaft to bolt the spool to it…If I only had a screw twice as long as what I have. > > No hardware store near me has lef hand threaded anything, and none of the lawnmower/leafblower/weedwhacker repair shops around me have the correct thread. > BTW…the reason this has a left-hand-thread is, becawse of the direction the spool rotates, if it had a regular right-hand thread screw, would constantly unscrew itself from the shaft. Call Homelite [http://www.homelite.com/service\_support/order\_parts](http://www.homelite.com/service_support/order_parts) , or take it to the nearest hardware store, get the thread and screw size (and obviously metric or english), and order the replacement online for left-hand thread. I assume you are saying you don’t want to bother extracting the residual screw shaft… ---
**Author:** ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)\ **Post date:** [June 18, 2009, 2:32am UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/3 "2009-06-18T02:32:41Z")
> [@Chief\_Pedant](#): > > Call Homelite [http://www.homelite.com/service\_support/order\_parts](http://www.homelite.com/service_support/order_parts) … Site says “parts unavailable…contact local dealer” I did, and they only have another screw the identical size. I need one twice as long. ---
**Author:** ![Gorsnak](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/gorsnak/32/7587_2.png) [@Gorsnak](https://boards.straightdope.com/u/Gorsnak)\ **Post date:** [June 18, 2009, 2:34am UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/4 "2009-06-18T02:34:50Z")
Might a local machine shop have a left-handed tap&die set, and manufacture one for you? Might cost more than it’s worth to you, I suppose. ---
**Author:** ![MC\_E](https://avatars.discourse-cdn.com/v4/letter/m/c77e96/32.png) [@MC\_E](https://boards.straightdope.com/u/MC_E)\ **Post date:** [June 18, 2009, 2:41am UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/5 "2009-06-18T02:41:46Z")
Did you try McMaster-Carr? > **[McMaster-Carr](https://www.mcmaster.com/)** > > McMaster-Carr is the complete source for your plant with over 595,000 products. 98% of products ordered ship from stock and deliver same or next day. ---
**Author:** ![Tom\_Tildrum](https://avatars.discourse-cdn.com/v4/letter/t/e95f7d/32.png) [@Tom\_Tildrum](https://boards.straightdope.com/u/Tom_Tildrum)\ **Post date:** [June 18, 2009, 2:59am UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/6 "2009-06-18T02:59:37Z")
You need a left-handed hardware store. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [June 18, 2009, 3:19am UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/7 "2009-06-18T03:19:39Z")
> [@Tom\_Tildrum](#): > > You need a left-handed hardware store. Or, a regular hardware store and a mirror… ---
**Author:** ![The\_Flying\_Dutchman](https://avatars.discourse-cdn.com/v4/letter/t/9fc348/32.png) [@The\_Flying\_Dutchman](https://boards.straightdope.com/u/The_Flying_Dutchman)\ **Post date:** [June 18, 2009, 3:56am UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/8 "2009-06-18T03:56:38Z")
> [@Enola\_Straight](#): > > …no, that’s not a double entendre. > > Here’s the deal: I have a gas poweed Homelite weed-whacker and the shaft the spool bolts to snapped halfway down it’s length. There is still enough thread inside the shaft to bolt the spool to it…If I only had a screw twice as long as what I have. > > No hardware store near me has lef hand threaded anything, and none of the lawnmower/leafblower/weedwhacker repair shops around me have the correct thread. > BTW…the reason this has a left-hand-thread is, becawse of the direction the spool rotates, if it had a regular right-hand thread screw, would constantly unscrew itself from the shaft. Not sure if this helps, but you could cut the head off a regular screw and screw in “head first”, say with vice grips. Then clinch the protruding part of the screw. ---
**Author:** ![Rick](https://avatars.discourse-cdn.com/v4/letter/r/9f8e36/32.png) [@Rick](https://boards.straightdope.com/u/Rick)\ **Post date:** [June 18, 2009, 3:59am UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/9 "2009-06-18T03:59:14Z")
> [@The\_Flying\_Dutchman](#): > > Not sure if this helps, but you could cut the head off a regular screw and screw in “head first”, say with vice grips. Then clinch the protruding part of the screw. mmmm no. It doesn’t work like that. ---
**Author:** ![Sunspace](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sunspace/32/1250_2.png) [@Sunspace](https://boards.straightdope.com/u/Sunspace)\ **Post date:** [June 18, 2009, 4:07am UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/10 "2009-06-18T04:07:53Z")
> [@beowulff](#): > > Or, a regular hardware store and a mirror… All you need do is get right-handed hardware of the proper specifications, then flip it over through a fourth spatial dimension. When you return it to this three-dimensional space, it will be left-handed. You can pay for the power bill for doing this by using the award money from your Nobel Prize, the one you got for figuring out how to do the flip. ---
**Author:** ![sailor](https://avatars.discourse-cdn.com/v4/letter/s/a587f6/32.png) [@sailor](https://boards.straightdope.com/u/sailor)\ **Post date:** [June 18, 2009, 4:15am UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/11 "2009-06-18T04:15:34Z")
> [@The\_Flying\_Dutchman](#): > > Not sure if this helps, but you could cut the head off a regular screw and screw in “head first”, say with vice grips. Then clinch the protruding part of the screw. I am not sure I understand. Are you saying that if I flip a threaded rod end for end the thread reverses direction? Because this is just so wrong. A thread is either right or left handed regardless of what end you are looking at. Or maybe I am misunderstanding something. ---
**Author:** ![The\_Flying\_Dutchman](https://avatars.discourse-cdn.com/v4/letter/t/9fc348/32.png) [@The\_Flying\_Dutchman](https://boards.straightdope.com/u/The_Flying_Dutchman)\ **Post date:** [June 18, 2009, 4:51am UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/12 "2009-06-18T04:51:50Z")
> [@sailor](#): > > I am not sure I understand. Are you saying that if I flip a threaded rod end for end the thread reverses direction? Because this is just so wrong. A thread is either right or left handed regardless of what end you are looking at. Or maybe I am misunderstanding something. :smack: ---
**Author:** ![Tom\_Tildrum](https://avatars.discourse-cdn.com/v4/letter/t/e95f7d/32.png) [@Tom\_Tildrum](https://boards.straightdope.com/u/Tom_Tildrum)\ **Post date:** [June 18, 2009, 1:32pm UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/13 "2009-06-18T13:32:09Z")
> [@sailor](#): > > I am not sure I understand. Are you saying that if I flip a threaded rod end for end the thread reverses direction? Because this is just so wrong. A thread is either right or left handed regardless of what end you are looking at. Or maybe I am misunderstanding something. He’s saying to rotate it through the fourth dimension. Bob Vila did this a few times on This Old House, and of course there was that episode of _Home Improvement_ where Tim tried to do it but wound up losing his pants in the process. ---
**Author:** ![JFLuvly](https://avatars.discourse-cdn.com/v4/letter/j/ac91a4/32.png) [@JFLuvly](https://boards.straightdope.com/u/JFLuvly)\ **Post date:** [June 18, 2009, 1:54pm UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/14 "2009-06-18T13:54:44Z")
Any machine shop should be able to turn a left thread on a lathe from a piece of stock. ---
**Author:** ![Scruff](https://avatars.discourse-cdn.com/v4/letter/s/6f9a4e/32.png) [@Scruff](https://boards.straightdope.com/u/Scruff)\ **Post date:** [June 18, 2009, 2:48pm UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/15 "2009-06-18T14:48:05Z")
Small Parts has left-handed threaded rods. would one of those do? [Search for Left Hand Thread](http://www.smallparts.com/s/383599011?refinementHistory=subjectbin%2Cbrandtextbin%2Cenc-merchantbin%2Cavailability_class%2Cavailability%2Creview-rating%2Cdate%2Cis_prime&searchKeywords=left+hand+thread&searchNodeID=383599011&searchRank=relevancerank&searchSize=20&searchBinNameList=subjectbin%2Cbrandtextbin%2Cenc-merchantbin%2Cavailability_class%2Cavailability%2Creview-rating%2Cdate%2Cis_prime) ---
**Author:** ![ElvisL1ves](https://avatars.discourse-cdn.com/v4/letter/e/5daacb/32.png) [@ElvisL1ves](https://boards.straightdope.com/u/ElvisL1ves)\ **Post date:** [June 18, 2009, 3:44pm UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/16 "2009-06-18T15:44:58Z")
You could rummage around the turnbuckle display in the hardware section of Home Depot. Each one has both a right-hand and a left-hand end, and perhaps there’s one with the right diameter and pitch for your part. ---
**Author:** ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)\ **Post date:** [June 19, 2009, 8:40pm UTC](https://boards.straightdope.com/t/i-need-a-left-hand-thread-screw/500132/17 "2009-06-19T20:40:48Z")
Turnbuckles! I’ll do that my next day off.