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Discussion Starter #1
Was wondering if any of you fellas would be kind enough to tell me what loader i have here.... Apologies in advance, i know this question gets asked frequently.





 

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Lee, mock it up and see where the loader aims, high center or low?

Very outdated design and its mig welded and mild steel. If the uprights are less than 3/16" thick don't even consider running that.
 

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Do you feel there is a problem with loaders being mig welded?

Looking for your honest opinion not starting shit.
No, I guess it could be done but for a racing part? No. I feel it should be of the highest quality. Like aerospace/racing quality parts. Quality materials, quality machine work, fixtured and tig welded. I see no reason to mig it over tig. I really cant get past the size of the welds with the migged parts.

IMO, there is alot of very low quality loaders out there that find there way into fast boats and thats a huge problem. We lost alot of boats a few years ago in one season, all from loader failures. Had a friend wreck a tunnel boat right in front of me who was lucky to get out of that crash alive. Not an area to cut corners. I do think there is a market for a loader for a 60 mph boat thats migged and mild steel but when it ends up in a fast boat we have a problem and thats impossible to control. Then look at the price tag on that part, hard to justify. Thats a $150 part at best IMO.

I gotta hand it to the racers this year, I had a handful of guys that caught cracked or broken mild steel loaders this season, had 2 situations where the bolts failed also. Bolts need to be changed more frequently.

SanDeggo, Ill supply you with lazer jet parts to build a loader your way if you want and we can run stress tests on it in your lab. Ive read your posts on welding in the past. If so, PM me an address.
 

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I'll come by the shop sometime, I'll be needing your services this winter.
For what it's worth I completely agree with what you wrote. I've seen bad tig welds on loaders. In that case I'd rather it be migged. People want that spread out dime look on their welds... That just creates stress risers.
 

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Chris, Are your loaders all chromoly? 4130 or something different? Ive alot of guys with do a mix between chomoly and DOM. Whats your thoughts on material?
 

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I'll come by the shop sometime, I'll be needing your services this winter.
For what it's worth I completely agree with what you wrote. I've seen bad tig welds on loaders. In that case I'd rather it be migged. People want that spread out dime look on their welds... That just creates stress risers.
Id really like to get together. Many of the failures this year (all mild steel parts) are at the edges of the welds and the mounting pad cant stay flat, it warps and wants to break. Keep in mind these parts had way too many laps on them and should have been replaced years before they did. Crazy amount of load on these things.

Question for you...Youd rather mig weld chromoly or cold roll? Cold roll is flat out not cutting it in racing or fast lake use and the stainless is too prone to warping.

Alot of the sanctioning bodies including NHRA will not allow a mig welded chromoly cage or other parts on their race tracks.
 

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Oh and for anyone wanting to test their loaders on the cheap.
Go to your local welding supply and get liquid penetrant. It's 3 spray cans, about 20 bucks.
Cleaner
Penetrant
Developer.
The part will be white and any cracks or defects will be red. It's cheap insurance.

Demo for my students letting the developer dwell.
 

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I have that same loader in my GW and it was mig welded and definetly looks like a newbie welded it. Im no weld pro but i do have a few certs for the squirt gun. Would you be able to pm me prices and pics of what loader works best in a 450lb GW?
 

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Chris, Are your loaders all chromoly? 4130 or something different? Ive alot of guys with do a mix between chomoly and DOM. Whats your thoughts on material?
Hi Desertrat.

Yes we run a mixture of materials...The parts that are not under any load are cold roll the rest is the good stuff and are lazer jet from plate, deburred to eliminate stress risers, etc. Doing everything we can do.

For racing...We leave them raw, no paint. We pull them out and clean them up each race for inspection. Crack checking will be happening at the races next season much like what you see the prop guys do between rounds. As the parts get more cycles on them they need to be watched even closer, just the way it is.
 

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That seems to make perfect sense. Do you use the laser of water jet for any specific reason or its just whats available locally?

Kyle
 

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Lazer is much cheaper. Problem with lazer is it leaves one helluva skin on the part where the lazer runs, even a carbide endmill cant handle it. Must grind the skin then machine. Id rather go waterjet, costs go way up though and there isnt much room for that. With all the deburring we do the skin comes off where it needs it and its all good. Things are working well up until this point.

The fixture is a 1.250 thick piece of blanchard ground steel, its serious. LOL.
 

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Id really like to get together. Many of the failures this year (all mild steel parts) are at the edges of the welds and the mounting pad cant stay flat, it warps and wants to break. Keep in mind these parts had way too many laps on them and should have been replaced years before they did. Crazy amount of load on these things.

Question for you...Youd rather mig weld chromoly or cold roll? Cold roll is flat out not cutting it in racing or fast lake use and the stainless is too prone to warping.

Alot of the sanctioning bodies including NHRA will not allow a mig welded chromoly cage or other parts on their race tracks.
I've hung out with your pops at the river. I'll swing by.

I don't like mig on chromo flat out. I don't like welding chromoly without proper controls such as post weld heat treating. Chromoly is wonderful when properly welded. One thing that you gotta keep in mind is 4130 chromoly has a tensile strength of about 80-90,000 psi. Much less if not stress relieved after welding. Cold rolled has about half as much.
It's common to weld chromoly with 80k tensile rod.
It's common to weld CRS with 70k rod.
That is if everything is welded right.
The more square inch of weld, the stronger the joint. For example when welding structural steel or pipe, we have bevels to fill the joint completely, or fillet welds with multiple passes like my dye picture above. In most loaders I have seen there isn't enough weld metal deposited to do the job.
If you only have 1/2 a square inch, that 80,000 psi doesn't mean squat.

Then think about how much leverage the loader places on the welded pad. The average loader has maybe 3 square inches of weld, if that depending on loader type. You can see that the load placed on a mild steel loader is just not going to cut it. Frankly, the math involved is beyond me.
I do know that in a loader you want the best of all mechanical properties. Tensile strength is only one when considering a material. You need ductility, fatigue strength, torsional strength, impact strength, toughness, etc... I don't know what the "best" material is for the application, but for a serious program, like yours, I'd venture to say you can't find the material you want at Mel's Metal Mart.

I for one would love to see some modeling and tests generated on the computer to see the loader improved.
 

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Makes me feel fortunate to have a water jet in the family!!!!

Im doing my damndest to take the quality that the high end drag guys use and what I am used to from the class 1 and trophy truck stuff and bring it all into a N/J or C/J roundy round boat. maybe thats why its taking me 2 years to build this thing.

Thanks for the metal info

Kyle
 

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Lazer is much cheaper. Problem with lazer is it leaves one helluva skin on the part where the lazer runs, even a carbide endmill cant handle it. Must grind the skin then machine. Id rather go waterjet, costs go way up though and there isnt much room for that. With all the deburring we do the skin comes off where it needs it and its all good. Things are working well up until this point.

The fixture is a 1.250 thick piece of blanchard ground steel, its serious. LOL.
Ahhhh water jet... The welders dream. No heat affected zone from cutting, no dross, just clean with acetone and weld er up. Water jet can be cheap Chris. The bigger the run the cheaper it is. I had pieces cut on my last boat and it's awesome. I'm pretty sure it was cut by desertrats fam
 

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Discussion Starter #19
Lee, mock it up and see where the loader aims, high center or low?

Very outdated design and its mig welded and mild steel. If the uprights are less than 3/16" thick don't even consider running that.
Chris, see photos attached below. Is it aiming low? Uprights are exactly 3/16" thick. With my intake set flat with the delta, the biting edge of the loader is 9/16" below delta bad. Intake has been drilled and tapped to 5/16. (Im using G8 annodised bolts with washers/nuts on engine side.)
I got the loader powdercoated before tearing down the Bahner, was in the boat when i bought it.











 

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I have the same open center loader. I trimmed mine to match the keel(rounded). It looks like yours is hanging way low. I don't know enough about delta pad boats, but i do wanna see the answer. I couldn't believe how much more my boat freed up after I trimmed the loader. It feels like you cut the rope of the anchor you've been dragging
 
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