square rod to normal pitch

[Alberto]

need advice please

i want to change my lift jack that has a square rod pitch to a normal but stonger pitch ,i want to make it longer so it can have a longer reach

the normal pitch i can get in ready bolt and thinking to go 20mm the square one is 16mm,i know the square tipe of pitch can handle the downwards pressure but cannot find that tipe of square anywhere .

[Spiceman]

It should be possible to cut square thread on a lathe. I think there's a very good reason why square thread is always(?) used.

[Olyfboer]

need advice please

i want to change my lift jack that has a square rod pitch to a normal but stonger pitch ,i want to make it longer so it can have a longer reach

the normal pitch i can get in ready bolt and thinking to go 20mm the square one is 16mm,i know the square tipe of pitch can handle the downwards pressure but cannot find that tipe of square anywhere .

Your requirement is rather vague. Can you clear up:

1. What a normal pitch is.
2. What a stronger pitch is.
3. How you intend fitting a 20 mm diameter rod in a 16 mm socket?
4. How you intend changing the socket the rod runs in?

[BBCT]

If it has a square thread, that's because it needs a square thread. Don't change to a "normal" 60-ish degree thread. Square threads are designed to handle axial loads (basically their sole reason for existing), "normal" threads are not designed to handle axial loads.

You probably won't be able to buy a rod like that off the shelf and it would save you a whole lot of time and effort to pay up and get an engineering shop to cut a square thread on a shaft for you. It's a pretty straightforward job on a lathe.

[Alberto]

1 normal pitch --anything from 1 to 10mm v pitch

2 a stronger pitch -- 4mm pitch is stronger than a 1mm pitch

3 i will drill a hole that will fit the chosen diameter and tap it

4 it won't be needed to change the socket depends on the diameter of the ready bolt ext.

ek is 'n machinist van beroep ,ek het nie tyd om vierkant skroef draad te sny nie so ek soek dit van die rak af dis nou 16mm diameter

omdat ek langer travel wil he, wil ek dit verander na 18 of 20 mm ek kan die gat in die moer gedeelte oop boor en tap ,dis nie rocket signs vir my nie

die probleem gaan kom as dit begin vrag vat, wat gaan die v skroefdraad maak ,dit moet 'n kamper van om en by 1 ton dra ,dit is nou as al 4 jacks op is op die kamper te lig en dan te laat sak op sy dolly ,

dis 'n projek wat ek wil toets sodat ek ander kan raad gee.,dis 'n blinkgat camper van sarel en wil die staan jacks modify .

[Spiceman]

1 normal pitch --anything from 1 to 10mm v pitch

2 a stronger pitch -- 4mm pitch is stronger than a 1mm pitch

3 i will drill a hole that will fit the chosen diameter and tap it

4 it won't be needed to change the socket depends on the diameter of the ready bolt ext.

ek is 'n machinist van beroep ,ek het nie tyd om vierkant skroef draad te sny nie so ek soek dit van die rak af dis nou 16mm diameter

omdat ek langer travel wil he, wil ek dit verander na 18 of 20 mm ek kan die gat in die moer gedeelte oop boor en tap ,dis nie rocket signs vir my nie

die probleem gaan kom as dit begin vrag vat, wat gaan die v skroefdraad maak ,dit moet 'n kamper van om en by 1 ton dra ,dit is nou as al 4 jacks op is op die kamper te lig en dan te laat sak op sy dolly ,

dis 'n projek wat ek wil toets sodat ek ander kan raad gee.,dis 'n blinkgat camper van sarel en wil die staan jacks modify .

Please let us know afterwards if metric pitch thread works. It will be interesting to know. My brain tells me the thread will want to bite. Not that I'm an expert.

[Alberto]

on heavy loads it will bite ,in my case yes ,now to plan B .

[MickPrado]

Those jacks are manufactured by RoadQ perhaps call them for an off the shelf heavy duty unit or replacement rod.

[plunger]

Machining a long square thread would be challenging even for a very experienced machinest. I wouldnt even try. But then Im not a machinest.

I think square thread as standard only starts at about 20 or 22mm in diameter. You probably would find stuff like that off the shelf oversees but here maybe its harder.

I would think its quite costly as well. Square thread handles loads easier but I wonder how a 20mm v thread would hold up. ?

[Alberto]

i have done this tipe square thread a couple of times and when i came at the workshop this morning ,what is waiting for me ,,the client asked me if i could repair the parking jack, nut that was stripped ,so i told him what i was up to and had a good laugh,so here is pic and a vidio if i can upload it

asking around if a v tipe pitch could work ,all heads was shaking even the client said that he made a repair with the 60degree v pitch, but the pressure on the thread let it bind ,so there goes my plan then ,

cutting the long square pitch is a challenge, but if you have a travel that runs with it ,it could work out ,but my longest is about 400mm .

[Alberto]

can anyone guide me how tp upload a vidio please .

[niclemaitre]

You can usually find longer than normal ACME type threads in the Mercedes and BMW jacks at a scrap yard.

[Alberto]

ok sticking to plan B, going to extend the legs and work it from there

started to check the turning mechanisme out ,that is the 2 gears that turns the shaft just to see that the thrust bearing does'nt look right for me ,they took the 2 backing spacers out and let it run on the box and shaft ,now as you can see it is cutting in both supports ,

i am going to take it up with the supplyers ,it won't be long something is going jam up ..

[Spiceman]

can anyone guide me how tp upload a vidio please .

As far as I have it, you have to upload it to a site like yootube en post the link.

[Spiceman]

Machining a long square thread would be challenging even for a very experienced machinest. I wouldnt even try. But then Im not a machinest.

I think square thread as standard only starts at about 20 or 22mm in diameter. You probably would find stuff like that off the shelf oversees but here maybe its harder.

I would think its quite costly as well. Square thread handles loads easier but I wonder how a 20mm v thread would hold up. ?

G clamps has smaller than 20mm shafts.

[plunger]

G clamps has smaller than 20mm shafts.

Yes but Im referring to off the shelf all thread in square . I think it starts at 22mm.
I see on alibaba it starts at 10mm. The rest of the world is spoilt compared to us. A square thread is difficult to cut.The tool has little clearance and a big surface area in contact at all times.
An acme or trapezoidal thread is much easier and just as good.

[Andrew Leigh]

Google "Thread Rollers", they should be able to knock something up for you.

[JohnnoK]

Call around the usual suspects, BoltFast, Fowkes Bros, Top Fast etc and see what they say.

If they don't have and it's so hard to do, pay some other sucker to sukkel turning it for you.

[Alberto]

Call around the usual suspects, BoltFast, Fowkes Bros, Top Fast etc and see what they say.

If they don't have and it's so hard to do, pay some other sucker to sukkel turning it for you.

read post no. 10 ,

so i will be the sucker then .