Tow Bar Questions, input needed

[ODdave]

So i have a couple of questions, I recently bought two tow bars that where missing a few things. One of them is complete, but the other is in need of pins, 1 leg and 1 foot.

Question #1
Are grade eight bolts as strong as the 3/4in pins???? I ask because i made some pins fron 3/4 #8 bolts and they turned out decent, ( see pics atached)

#2
One of the bars had what i thought to be a pretty niffty foot on it, it has both 3/4 & 1 in ends, (I included a pic), Dose anyone know where i may find another one of these??? It apears to be cast where others are forged. Is that ok or should i not use these.

#3
Dose anyone sell tow bar parts, ie leggs? Businesses or members?

Thanks Guys.

 

[gimpyrobb]

I have parts what do you need? That pin should do just fine(nice work too). I have used that style foot before and had no issues. Not sure where to find a second, maybe egay.

 

[Recovry4x4]

I have several pins that were hand made with the bar I use most often. All of the pins we made were heated up cherry red and oil quenched. Haven't had a problem in 3100 miles towing (+ what other users have logged on my towbar). I also have a pair of the doubles but use them primarily for the 3/4" size as I have one inch adapters.

 

[wsucougarx]

Tractor supply should have the pins you need. Albeit they won't be exactly what the military uses.

 

[Oldfart]

I must say that is a really nice job of making pins. ~~ I bought a pile o'towbars from GL and I too need some parts to make every thing complete. My pile only had feet with 3/4 inch pins and not enough pins for the feet I got and not enough pins for the tow bar assemblies. So far I have set one tow bar up with feet using 3/4 inch bent pins. On three of the tow bars I made adapter sleeves to make the 3/4 inch pin in the feet 1 inch so they work on my son's M35 and 5 tons. To make sure the 3/4 inch pin would handle the load, I checked the shear on grade 3's and Grade 8's. Grade 3's shear at about 3000# and Grade 8's are near 10,000#. The way all the pins on the tow bar are set up, they are in a double shear application which would nearly double the shear rating. I could not find the shear rating of the military pins, but the medium tow bars are rated at about 37,000# towed load. Two 3/4 inch grade 8 feet pins in a double shear application are just about equal to the towed load rating of the tow bar. The same would be true for the rest of the tow bar pins except for the single pin at the lunette ring and I assume the solid leg on one side would spread the load enough that the single pin would function within the double pin load rating. ~ I am looking for a set of those combined feet for my own tow bar.

 

[jwaller]

austin aviation on ebay always has a stock of pins and parts.

 

[SCSG-G4]

Austin aviation on e-bay is known as beltfed34, and he has the parts!

 

[ODdave]

i did see a coment on here or feebay from austin saying he has a shortage of pins. I will defiantly check with him again though.

Thanks for the info & comments on the pins guys!

 

[Recovry4x4]

Member Sermis had a boat load of pins at one time. After having made my own in the past, I did take the opportunity to purchase an extra set. I also have a few oddballs as spares.

 

[KsM715]

Whats the value on the double adapter set? I have both the double adpters and a pair of 1" feet and a pair of 3/4" feet. I'm going to sell something I just dont know whether to keep the double set and sell the other 2 or vice versa.

 

[ODdave]

finished blasting and painting the tow bars this weekend. I bought new stickers from left cost customs and man do they look great. (of corse i put them on wrong do to being distracted) Also finished up a few more pins to complete everything.

 

[ODdave]

ok, i think i have found a lil info on "bolt strengh" Please tell me if this sounds right,
Grade 8 @ 1in = 80,000lb tensile strength
so in theory
Grade 8 @ 3/4 = 60,000lb right?
shear strength = %60 of the tensile strenght so
Grade 8- 3/4 = 36,000lb shear strength
2 x 36k = 72k (bar is using 2 pins)
Tow bar is rated at 39k so i should be good in theory right?????

 

[rosco]

The bolts will do just fine BUT, get them long enough so that there are no threads on the bolt shanks, until they exit the tow bar feet. Then you can cut/drill them for the keeper pins. Otherwise you have less then the desired shank diameter, due to the root diameter of the threads!

Lee

 

[televisionman007]

I have parts what do you need? That pin should do just fine(nice work too). I have used that style foot before and had no issues. Not sure where to find a second, maybe egay.

dont be sellin mine chris

 

[ODdave]

The bolts will do just fine BUT, get them long enough so that there are no threads on the bolt shanks, until they exit the tow bar feet. Then you can cut/drill them for the keeper pins. Otherwise you have less then the desired shank diameter, due to the root diameter of the threads!

Lee

The pins in the first pic on this thread where made from bolts. I made Shure no threads where there. Is anyone else in need of these pins? I can do the 1in ones also.

 

[Pipehitter35]

Check out memphis equipment

 

[gimpyrobb]

Dave, how much for some 3/4" pins?!

 

[73m819]

I brought 3/4 hitch pins off ebay, then shortend them, and also got some from tractor supply

 

[ODdave]

Dave, how much for some 3/4" pins?!

Rob, sorry i have been real busy the last few days, shoot me a pm.

 

[ODdave]

So i have tryed to contact beltfed about a tow bar leg and have had no luck. Is he on here often??? Dose anyone here have personal contact with him and be willing to help out? If no luck is there another sorce? i picked up 4 1in feet and am realy antsie to get these completed. (sorry about being impatient guys)