How trailers are made.

[noelm]

1 hour ago, Fab1 said:

He mentioned it's alloy.Weird.

Even with galvanised trailers you'd think they could have the holes for galvanizing but plug them afterwards.

I think the cross members were steel?

[Fab1]

9 hours ago, frankS said:

The winch post , although the actual post looks sturdy enough the tiny little bit of bracing is pathetic and what the winch itself is sitting on is less than ideal, the roller supports for the winch, which you pull the boat tight against , just 2 skinny long pieces of flat metal will bend with just a slight touch to the side.

If you were to drive the boat on and bump that roller with any sort of force, ( which is not hard to do ) it will bend.

Your friend should have this section of the trailer re-enforced before it causes him hassles. 

Frank

Agree.Play dough looks stronger.I'm talking solely about cross members being removable.If you get water up to the top of the winch post you know you've definaetly backed in too far.😂

8 hours ago, jeffb5.8 said:

I have Blue Skids and centre rollers and if the ramp has a good slope then i cannot undo the safety or strap until I'm ready to launch and then its just a gentle push and away it slides.

Pretty sure my trailer had a bolt on rear cross member, will have to stick my head under again, being alloy I just use a scotch brite pad once every now and then to clean the salt off the under side, but never had a issue, the axle is the worst part.

Also i hate that mine has holes drill in the cross members top and bottom, why not sealed tubes, its hard to wash out properly since the ends are sealed. 

 

All trailers should have cross member drainage holes sealed and side rail ends plugged after galvanizing. But the manufacturers know that you won't be returning for a new trailer for years to come.

1 hour ago, frankS said:

Most Gal places refuse to do 2nd hand trailers as there is too much risk with Warranty work, people take rusted out trailers in and expect them to be in new condition once they are galled.

Trailers rust from the inside out, as most on here would know.

Yes should be plugged maybe with rubber grummet so that water does not get inside the metal.

C channel is becoming more popular these days for good reason.

Frank

Agree.Plugged drainage holes and side rail ends is the go on all new trailers.Don't hold your breath waiting for it to happen.

1 hour ago, noelm said:

I think the cross members were steel?

I thought just the axle was Gal.

Maybe he can clarify.

A better option for him cleaning the underside with scotchbrite every now and then would be the mrs doing it.😂

[jeffb5.8]

20 hours ago, Fab1 said:

thought just the axle was Gal.

Maybe he can clarify.

A better option for him cleaning the underside with scotchbrite every now and then would be the mrs doing i

Correct the axle is Gal, which from new I painted in Galmet to add protection

Trailer is full Alloy and i use the scotch brite just to clean it up when it goes a little tarnished and when the seaweed is heavy at Shoal bay as it sticks to everything.

 

 

[Fab1]

3 hours ago, jeffb5.8 said:

Correct the axle is Gal, which from new I painted in Galmet to add protection

Trailer is full Alloy and i use the scotch brite just to clean it up when it goes a little tarnished and when the seaweed is heavy at Shoal bay as it sticks to everything.

 

 

Give silicon spray a try.

[rozza_b]

On 6/20/2021 at 6:30 PM, noelm said:

Just to add, most home builders could not build a trailer in 4 days (unless you have everything at hand, and are a tradesman boilermaker or similar, working weekends or nights, it will take a week or two at a minimum. Remember you are building without plans as such, you need to buy stuff as you go, unless you have a full on workshop at your disposal.

took me and my mate 2 full days to build my trailer in his workshop, with all the parts and materials on hand, i also done all the drilling on hangers etc before we started building. 

 

On 6/20/2021 at 6:25 PM, noelm said:

There's a lot to home building, lots of people scrounge stuff for free, and use odds and ends bought cheap, but, if you're building "new" then everything has to be bought from a shop. Most of us know someone who can get us a discount, but there's a lot of stuff goes into a trailer, then there's galvanising and lights and stuff, that's without consumables and electricity, but, the end result can be satisfying and quality can be guaranteed.

cost me just under $4k in parts and materials, cost price through my mates business that is

[noelm]

Yep, that just about sums it up, working in your home shed/garage triples the time to make stuff.

[Fab1]

5 hours ago, rozza_b said:

took me and my mate 2 full days to build my trailer in his workshop, with all the parts and materials on hand, i also done all the drilling on hangers etc before we started building. 

 

cost me just under $4k in parts and materials, cost price through my mates business that is

How much for a suitable trailer off the shelf?

[rozza_b]

Just now, Fab1 said:

How much for a suitable trailer off the shelf?

Umm my guess for a full drive on set up that is custom made to suit the boat maybe $8k-9k, ali trailers sure arent cheap these days 

[campr]

In 1982 I bought a new quinnie with a Coaster branded trailer that had bolted on cross members that was great.  Easier to flush out after using and when the rear cross member got rusty it was easy to replace.  I recently got a new trailer for my current quinnie and would have got a similar one if I could have found one.  Ron 

[JonD]

Got someone offering to build me a stainless steel trailer for my latest boat, why so few stainless trailers ?

[frankS]

10 hours ago, JonD said:

Got someone offering to build me a stainless steel trailer for my latest boat, why so few stainless trailers ?

Weight. I once built an independent suspension system for a trailer from Stainless Steel but it weighed as mush as the rest of the trailer put together. As far as I know it is still being used up in Harvey Bay QLD on a boat trailer.

Frank 

[noelm]

Stainless is quite tricky to build a trailer out of, first off, it gets brittle when welded, then the welds and surrounding area needs to be treated to prevent it rusting in the heated area, add to that, it's weight and availability in the right extrusions in the right grade stainless is not easy or cheap.

[dunc333]

id buy a stainless trailer off frank anyday before a china gal  .you get for what you pay for

[Smobaby]

Reguarding stainless trailers the material price would be triple that of mild steel. The only structural stainless is duplex $$$. The normal 316 is not a structural product which will lose integrity with flexing of a trailer. The welds won't break if done correctly to proper weld procedure by qualified welders, but the metal next to the weld will be compromised. Pasivating the welds after fabrication will reinstate the chromium to the surface preventing corrosion it all costs money. For stainless not to tea stain (rust) it must be mirror finish. Stick to structural aluminium. Will be cheaper and all metals still corrode just some quicker. Reguarding galvanising if done properly should last for a decade at least. Problem is the material that's used in the manufacturing cheaper imported steels have too much silicon content which doesn't allow the zinc to penetrate the metal. Been dealing with this for years on boats- trailers and commercial applications. Don't block drain holes flush them with fresh water.

[Fab1]

12 minutes ago, Smobaby said:

Reguarding stainless trailers the material price would be triple that of mild steel. The only structural stainless is duplex $$$. The normal 316 is not a structural product which will lose integrity with flexing of a trailer. The welds won't break if done correctly to proper weld procedure by qualified welders, but the metal next to the weld will be compromised. Pasivating the welds after fabrication will reinstate the chromium to the surface preventing corrosion it all costs money. For stainless not to tea stain (rust) it must be mirror finish. Stick to structural aluminium. Will be cheaper and all metals still corrode just some quicker. Reguarding galvanising if done properly should last for a decade at least. Problem is the material that's used in the manufacturing cheaper imported steels have too much silicon content which doesn't allow the zinc to penetrate the metal. Been dealing with this for years on boats- trailers and commercial applications. Don't block drain holes flush them with fresh water.

I'm yet to see a galvanised trailer that flushing drain holes with fresh water has stopped them from rusting from the inside out.

I think they should be sealed after galvanizing but the manufacturers know they would be shooting themselves in the foot.

[dunc333]

i agree fab 1 next time i buy new gal trailer i will turn over and fill with sump oil and plug holes .i reckon you will nearly double the life of the cross members cheers dunc333

[Fab1]

2 hours ago, dunc333 said:

i agree fab 1 next time i buy new gal trailer i will turn over and fill with sump oil and plug holes .i reckon you will nearly double the life of the cross members cheers dunc333

My trailer had open ends on the cross members and holes top/bottom in the centre of them also.I blocked them off and filled them.

[frankS]

To plug the ends and holes on a galed trailer you first have to remove the Galvanizing from the area you need to weld. This is mostly done by grinding the gal off till you get back to bare metal.

Welding galvanizing puts out a poisonous vapor ( think it's similar to cyanide ) so you need to be careful what you are doing.

Once the weld is completed you can cold gal the area with a couple of coats of cold gal paint but the end job is never as good as proper galvanizing, and needs care to maintain .

  Frank

[Fab1]

5 hours ago, frankS said:

To plug the ends and holes on a galed trailer you first have to remove the Galvanizing from the area you need to weld. This is mostly done by grinding the gal off till you get back to bare metal.

Welding galvanizing puts out a poisonous vapor ( think it's similar to cyanide ) so you need to be careful what you are doing.

Once the weld is completed you can cold gal the area with a couple of coats of cold gal paint but the end job is never as good as proper galvanizing, and needs care to maintain .

  Frank

Exactly.Or you can just use knead-it like I did and avoid doing all that creating more issues than you began with.

I let my trailer/boat sit in our dam for 2 days after I sealed the cross members before filling them up as a test.(I like testing things for my own piece of mind).

  I opened the holes again to test for water ingress and not a drop was inside the cross members.Dry as a bone.

I sealed and filled the cross members up after that.

  Cheers.

[XD351]

Welding Gal can give you cadmium poisoning , been there had that it ain't pleasant and welding over Gal adds impurities to the weld pool and can weaken the weld .

Better to have drain holes and if you build your own trailer allow for these so you can flush out the chassis , these drain holes also allow the Gal to plate the inside of the chassis and you can buy a dedicated spray gun to coat the inside of the box sections with fish oil as well ( even if galvanised ) but if you have cleaned the parts ( ground off the paint ) before welding the pickling process should clean everything inside the welded area so you get a good coating of Gal inside the box sections - best to talk to the galvanisers first and they will help you get the best results.

If you have to dunk your trailer in the salt to launch - consider all of your trailer as a consumable item  Galvanised or not .

[Smobaby]

Fab you can see the speckled effect on your galvanising this tells me that the material used has too much silicon content cheap steel, which why the galvanising  coverage is not up to any standard the coating should be much thicker no QA there. But that's what you get from mass produced products.

[kingie chaser]

12 hours ago, Smobaby said:

Fab you can see the speckled effect on your galvanising this tells me that the material used has too much silicon content cheap steel, which why the galvanising  coverage is not up to any standard the coating should be much thicker no QA there. But that's what you get from mass produced products.

Mine a bit like that to.

Dunbier trailer!

[Fab1]

21 hours ago, Smobaby said:

Fab you can see the speckled effect on your galvanising this tells me that the material used has too much silicon content cheap steel, which why the galvanising  coverage is not up to any standard the coating should be much thicker no QA there. But that's what you get from mass produced products.

I think you'd be hard put to find a trailer manufacturer in existence that hasn't cut costs by using thin galvanizing.Look at a trailer from say 30yrs ago the galvanizing is superior to the rubbish now.

[Fab1]

23 hours ago, XD351 said:

Welding Gal can give you cadmium poisoning , been there had that it ain't pleasant and welding over Gal adds impurities to the weld pool and can weaken the weld .

Better to have drain holes and if you build your own trailer allow for these so you can flush out the chassis , these drain holes also allow the Gal to plate the inside of the chassis and you can buy a dedicated spray gun to coat the inside of the box sections with fish oil as well ( even if galvanised ) but if you have cleaned the parts ( ground off the paint ) before welding the pickling process should clean everything inside the welded area so you get a good coating of Gal inside the box sections - best to talk to the galvanisers first and they will help you get the best results.

If you have to dunk your trailer in the salt to launch - consider all of your trailer as a consumable item  Galvanised or not .

Agree to a certain extent.I'm not talking about custom built trailers.

  I'm talking about mass produced off the shelf box section trailers.

  There's no way of adequately flushing the cross members out with just water.

All steel galvanised trailers should be manufactured with c section steel at a minimum and save the rhs for building things like box trailers etc that don't see salt water immersion.

  Problem is trailer manufacturers want us to come back asap and buy another trailer from them.

The back third is where most trailers rust and that's where the last and second last crossmember is along with the axle/s and springs.

 If you can prolong the rust from occurring here by sealing them up you're leaps and bounds ahead of the guys that try to give their trailers a quick rinse which only really rinse the surface of the trailer not the insides.

 

 

9 hours ago, kingie chaser said:

Mine a bit like that to.

Dunbier trailer!

Mines a dunbier too.

Edited July 10, 2021 by Fab1

[Smobaby]

It's not the galvanising as much  as the inferior materials used. Seriously the difference would only be two or three hundred dollars to do it properly, as you know everything is made to a price now, not like the old days it was built to last and companies supported their products . I do a lot of work for Sydney Trains where I have to warrant a 25 year warranty on galvanising, pitty  trailer manufacturers were not subject to similar legislation. Most trailers are manufactured offshore and assembled in Australia.