Boat Trailer project

[brett62]

I am just about to start building a new trailer for my boat. I am using a mate’s trailer at present as I purchased the boat without a trailer. It’s a 7m fiberglass and loaded up with fuel and fishing gear it will weigh about 2.4 ton. Cost of buying new was $15,000 and that was without stainless steel brakes.

I have been kicking around what to make it out of, steel RHS, channel or aluminum. Due to the weight of the boat and max tow capacity of the tow vehicle aluminum would be the pick and also the rust factor. After changing my mind many times and speaking with a few engineers that I work with the decision was to build with a combination of steel RHS and Channel. I wanted to go multi roller and priced up the frames, etc. to save fabricating the frames to make life a little easier. Well the price was off the planet.


A list of main materials to use.

Main rails 150 x 50 x 4mm RHS
Cross members 100 PFC
Main draw bar 150 x 50 x 5mm RHS
Multi roller frames 40 x 3mm SHS
Keel roller frame 100 x 50 x 8mm angle.
Tandem axle with 8 leaf springs (rocker) 6 stud Land cruiser hubs
Stainless steel hydraulic disc brakes with 12in rotors (air over hydraulic)
Keel rollers will have Stainless steel bars.


Started doing up a drawing of the set up but have not completed fully. I have attached a model shot to give an idea of what the plan is. I do intend on towing some distance from time to time and I know that there will be a few that would have gone for Aluminum. I can tell you that the cost of the galvanizing would certainly just about cover the difference in cost of building the trailer out of aluminum. I don’t have my aluminium welding equipment anymore and certainly may have gone that way if I had. Steel will rust if not taken care of but aluminum has its issues also. The big gain would have been the weight difference which was some 300kg.

If anyone is interested I will post pictures as I build and also information on where materials are purchased as I have been researching trailer parts and especially the braking system as it is a major cost. I am still working on what brand to use as they all have pros and cons. I know there is many members that have built their trailers and have read many post on the subject. Interesting reading on some of the problems and designs. I guess I should have call this another trailer build post. Any comments from the forum will be well received.

[PB]

Try using a section at least 75mm - 100mm wide for the draw bar as the bolt holes on the coupling are at 58mm centers. Also you are going to have a lot of flex in the rear section of that design, I would be looking at putting a cross member right at the back to tie it all together.

[brett62]

PB the distance of the rear of the trailer is 850 mm. It looks a lot more due to the angle of the model shot, there will also be bracing gussets which I have yet to draw. The back section will actually pivot down to guild the boat on and off.

The trailer I am using at present has much the same set up and it guilds and locks the bow in great when driving the boat on. It also takes away the issue of running the bow into steel sections as you can't see the ass of the trailer to well when its under water. The weight will be taken on the fixed rollers a little further up and keel rollers.

The draw bar I have not completed drawing as yet but the tow hitch will be raised off the RHS section to better suit the tow ball height of the vehicle.

Thanks for looking at the design and your comments. Once I finish the drawing I will post.

[brett62]

Well I am under way with the construction now.

Have decided to go with DEEMAXX S/S brakes (12in vented S/S Rota, calipers with ceramic pads and also S/S landcruiser 6 bolt hubs.

Has anyone used this brand of braking system?

Some photos







IMGP2408 (Copy).JPGIMGP2413 (Copy).JPGIMGP2417 (Copy).jpgIMGP2403 (Copy).JPGIMGP2402 (Copy).JPGIMGP2400 (Copy).JPG

[ovakil]

Where did you get steel & fittings ?
I'm needing to do my trailer. Similar size to yours.
I was going to copy the trailer I have.
I have a mig,going to tack it together then get a decent welder to finish it off.
Looks good.

[brett62]

I purchased the steel from Citi-Steel. Only charge $75.00 to deliver with a crane truck great prices. I shopped around I can tell you.

Making all the fittings (roller frames etc) myself as the price to buy ready made was !!!!!!!!!!!!!!!!! If you have trouble getting someone to weld for you give me a call as I am just at Caboolture.

Where did you get steel & fittings ?
I'm needing to do my trailer. Similar size to yours.
I was going to copy the trailer I have.
I have a mig,going to tack it together then get a decent welder to finish it off.
Looks good.

[grinner2]

Who is doing your h.d.galv?

[wrxhoon]

They are similar to Kodiak and about the same $$, the guy that owns D-max previously worked for Kodiak.

Well I am under way with the construction now.

Have decided to go with DEEMAXX S/S brakes (12in vented S/S Rota, calipers with ceramic pads and also S/S landcruiser 6 bolt hubs.

Has anyone used this brand of braking system?

Some photos







IMGP2408 (Copy).JPGIMGP2413 (Copy).JPGIMGP2417 (Copy).jpgIMGP2403 (Copy).JPGIMGP2402 (Copy).JPGIMGP2400 (Copy).JPG

[brett62]

Who is doing your h.d.galv?

Still working on the Hot Dip. I did get a price of $2.90 per KG from a company on the north side. The company that delivered the steel to me are on the south side of Brisbane and have given me a couple of places to look at. They will also pick up the trailer and return. I just need to check that their bath is long enough to take the frame which is 8m. If anyone could recommend a company I would be thankful.

[brett62]

They are similar to Kodiak and about the same $$, the guy that owns D-max previously worked for Kodiak.

Thanks for the information. I am heading in the right direction then?

[ovakil]

Still working on the Hot Dip. I did get a price of $2.90 per KG from a company on the north side. The company that delivered the steel to me are on the south side of Brisbane and have given me a couple of places to look at. They will also pick up the trailer and return. I just need to check that their bath is long enough to take the frame which is 8m. If anyone could recommend a company I would be thankful.

I'll find out who does our caravan chassis if you like.

[brett62]

That would be great. Its hard to understand that the coating is costing more that the materials to build the trailer.

I tried a few places on the south side today but as it is the weekend they are all enjoying the weekend off.

I am purchasing most of the running gear from a place call Huntsman in VIC. They have been the best price and their parts all meet the standards so I don't have problems when it comes time to register the trailer. They impressed me with suppling the price with good gear such as bearing buddies standard on their hubs and shackle pins you can grease on the springs etc.

Just to give you an idea I got a price to supply S/S callipers and S/S rota with Landcruiser 6 bolt hubs and was quoted $2000 per axle from a local supplier and the hubs were only gal. Huntsman quoted $1250 per axle with S/S hubs also with bearing buddies and heavy duty wheel bearings. A set of tandem springs local was $750, Huntsman $520 and that was for 9 leaf 2000kg. I also will be buying the brake actuator from them for $950 and they have thrown in the controller worth $200 as I am spending so much with them. Even buying the rims and tyres from them. They said they can do the freight for about $300 if I ship all together.

The only part of the trailer I can't get from them is the winch and boat rollers as they don't have winches and not much of a range of boat rollers. The boat rollers I have priced in Brisbane from Polymer and can get them for just under a $1000. Still need to work out the winch as I am kicking around putting a electric winch on. Not sure what to buy as yet there are that many different types.

I'll find out who does our caravan chassis if you like.

[marto78]

Have you tried Boat Trailer Spares at Coopers Plains for your rollers?

I have just finished rebuilding my trailer and found them to be very competitive on prices.

[brett62]

No, but I will give them ago.

Have you tried Boat Trailer Spares at Coopers Plains for your rollers?

I have just finished rebuilding my trailer and found them to be very competitive on prices.

[tunaticer]

You will pay a 3D rate for your galvanizing wherever you go, you are paying for the room in the bath for the duration of the dip plus the zinc weight. The $2.90 per kg rate is an average of what boat trailers cost......they will average out their costs over multiple jobs to maintain target.
Shop around, I feel the $2.90 is not a cheap rate. Give them the sizes of the trailer and ask what the 3d rate is for that item.
I think all galvanizers in Brisbane are running 10m + baths these days.