Well - I'm on a mission now. Found someone who would grit blast it, and I have an industrial galvaniser nearby. Shall see how the costs work out in a few weeks when its all done.
....and finally did get an answer on the trailer jacking mechanism - it should come apart - pinion gears held in place by roll pins. Galvanising the springs is a no, no - hydrogen stress corrosion cracking due to the acid pickle before hot dipping. All holes to be enlarged - allow about 1mm extra for the zinc coating around a half inch hole. All sealed members to be opened so we don't have any explosions.
I'll put the boat in the water, then commence dismantle of the trailer. Tow to the grit blaster and remove mud guards and axle plus springs and the tow hitch. Grit blast then reassemble. Tow to galvaniser and dismantle again etc. Might get out of it for about aussie $1000. We'll see.
Craig
Trailer Galvanising
Edurbin, How old is your Mac trailer? Mine is 5 years old and is in OK condition and at this rate will last easy another 5 years with care. I agree with Aya and use the Mac trailer for all its worth. To put $1000 into a trailer that still needs to be able to carry more weight (according to Chip anyway) could be spent on some really nice gear. We need to think about this some more and look at other solutions to the rust problem. Maybe MacGregor will bring out a new Mac galy trailer at a reasonable cost.
BK,
Macgregor should offer a galvanised trailer option up front. Many people like me have the 100% saltwater use. My trailer is 12 months old. I've been diligent to coat it regularly with marine lanolin, and to wash off with fresh water. Generally its holding up well. But in the less obvious spots, the rust is certainly beginning. Also, I got on my hands and knees and looked on the bottom side of trailer main side sections. The rusting has begun. Addressing the problem early should ensure my own peace of mind about maintaining the structural integrity of a trailer already close to its design limits. For my application, the money will be well justifed.
Craig
Macgregor should offer a galvanised trailer option up front. Many people like me have the 100% saltwater use. My trailer is 12 months old. I've been diligent to coat it regularly with marine lanolin, and to wash off with fresh water. Generally its holding up well. But in the less obvious spots, the rust is certainly beginning. Also, I got on my hands and knees and looked on the bottom side of trailer main side sections. The rusting has begun. Addressing the problem early should ensure my own peace of mind about maintaining the structural integrity of a trailer already close to its design limits. For my application, the money will be well justifed.
Craig
Trailer Galvanising
Well its all done now. How did the costs work out ?
1. Grit blasting - 1 hour at $A270.
2. Bolts nuts and drill bits and brake fluid and rivets etc. and circlips for tow hitch (broke one which was hard to replace - thickness) about $A100.
3. Galvanising about 200 kg - $A380.
4. Put boat in water for 2 weeks - no charge for me.
5. Dismantle trailer and make holes bigger - day and half of my time - no charge.
6. Reassemble and bleed brakes - day and half of my time - no charge.
7. Towing between my house and grit blaster - remove axle and springs on site - no charge. Grit blast. Put the axle back on and tow to galvaniser. Remove axle. Galvanise trailer. Put axle back on and tow home - no charge.
About $A750 (roughly US$570) all up. Pleased I wasn't charging for my own time - would cost a bit to get somebody to do the assembly and disassembly and running around.
Couple of tips.
1. My trailer has been in use for about 10 months. I took the opportunity to bleed the brakes - rusty sediment in the hydraulic line was significant. Now I know how, I'll be bleeding the brakes every year.
2. Because the trailer is open channel section construction, drain holes for the molten zinc need to be drilled at each corner where the crossmember channels weld to the trailer side channels. Otherwise the zinc will pool in the channel - really thick coating !
3. My trailer was dipped lengthways - held by the tongue. Unfortunately, this allowed quite a bit of zinc oxide dross to collect inside the square section tongue of the trailer. Had a half day job to chip and drill it clear so the brake line could be reinstalled. Not sure what could be done to avoid this problem.
Should get many years out of the trailer in saltwater use from here on.
Happy sailing,
Craig.
1. Grit blasting - 1 hour at $A270.
2. Bolts nuts and drill bits and brake fluid and rivets etc. and circlips for tow hitch (broke one which was hard to replace - thickness) about $A100.
3. Galvanising about 200 kg - $A380.
4. Put boat in water for 2 weeks - no charge for me.
5. Dismantle trailer and make holes bigger - day and half of my time - no charge.
6. Reassemble and bleed brakes - day and half of my time - no charge.
7. Towing between my house and grit blaster - remove axle and springs on site - no charge. Grit blast. Put the axle back on and tow to galvaniser. Remove axle. Galvanise trailer. Put axle back on and tow home - no charge.
About $A750 (roughly US$570) all up. Pleased I wasn't charging for my own time - would cost a bit to get somebody to do the assembly and disassembly and running around.
Couple of tips.
1. My trailer has been in use for about 10 months. I took the opportunity to bleed the brakes - rusty sediment in the hydraulic line was significant. Now I know how, I'll be bleeding the brakes every year.
2. Because the trailer is open channel section construction, drain holes for the molten zinc need to be drilled at each corner where the crossmember channels weld to the trailer side channels. Otherwise the zinc will pool in the channel - really thick coating !
3. My trailer was dipped lengthways - held by the tongue. Unfortunately, this allowed quite a bit of zinc oxide dross to collect inside the square section tongue of the trailer. Had a half day job to chip and drill it clear so the brake line could be reinstalled. Not sure what could be done to avoid this problem.
Should get many years out of the trailer in saltwater use from here on.
Happy sailing,
Craig.