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Discussion Starter #1 (Edited)
hey guys grab a chair and get up close.u might like this. first off this my rendition of an article by a guy named trek that i saw on marion county speedway.it is very informative and something that you can do!!i,ll do half tonite and finish later.things you,ll need. get some foam blanks from sluggoslots on ebay.the seller slade is a prefered seller next a mandrell from jw,s speed again, top shelf guy.knock out the plug from the blank and mount it on the rim that you,re gonna use.with a nice small pair of scissors trim em down close to the size you want.this is not the finish size so make em big.next chuck,em up on a drill or dremmel and get the sidewalls closer to finish size. use some 220 or so paper you,ll know what works best after 4 or 5 sets you make.o.k. take the jw,s mandrell chuck it and secure it so it,s stable. lay both rough sized foams on mandrell and cranker up. check the pics u see i,ve got a box to catch foam dust.do the box catcher cuz it could get messy.now start to even up the foams ,maybe even try some different paper sizes to get a feel how the foam behaves.you,re gonna need a tube of flowable silicone.so go get some of that stuff.i,m here to tell ya that you,ll make a bunch of crappy sets at first but you will soon be makin silifoam tires that work quite well and you,ll be very proud of youreself cuz u saved a bunch of money and u mad,em you,re self!!.so fellas check the pics out .i,ll post more soon. class dismissed!! for now.
 

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Discussion Starter #3
hey blubyu ya just rub/ message the silcone in with youre fingers then spin it off. let it dry for well till its dry then repeat maybe 3 times you,ll see. and yes more to come. did/nt want to show everything in 1 sitting.go ahead and get started on rounding up materials.youre gonna like the way they come out.
 

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Thanks,how much does one spin add to the size? I'll need to know what size to cut my foam too before applying the 3 coats so I can have the right size - range for my cars. Thanks again,can't wait for my material now! This should save me a bunch of $$$ on tires.
 

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Discussion Starter #5
i cant really say with expertise but u will see 1 coat has a dimple finish.2nd coat kinda fills in low spots 3rd coat really is nice finishing coat! i,ve been using pemitex flowable silicone. as for the flowable silicone i kinda wonder is it all the same?as for cutting to size. get em close then tru em i tick small then buildup with the flowable. be read to make some really bad ones.you will get better.to date i,ve fashioned up mybe 30 sets. no 2 are the same but simular/close.i dont have time to post pics right now but , i will tonite. youll see a lil better/ how to.
 

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If you're dipping them and spinning them on low speed in your Dremel,each coat should add between 2 to 3 thousands.
This dipping trick also works to rebuild old silly-foam tires.There's a few differant varieties of flowable silicone's out there,i used to use Dow Corning's,but it's tougher to find then Permantex's version,both accomplished virtually the same end result.
If you can,while they're curing,flip them over,let them stand up for a bit,then flip them upside down and hang them for a bit,less tendenancy for the silicone to puddle on the end of the tire.
Stick em in old axles,and have a bunch to do at one time.
I set a couple old cardboard boxes up,to stick the axles in,then used a hair dyer under the boxes to speed up curing time.:thumbsup:
 

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If you're dipping them and spinning them on low speed in your Dremel,each coat should add between 2 to 3 thousands.
This dipping trick also works to rebuild old silly-foam tires.There's a few differant varieties of flowable silicone's out there,i used to use Dow Corning's,but it's tougher to find then Permantex's version,both accomplished virtually the same end result.
If you can,while they're curing,flip them over,let them stand up for a bit,then flip them upside down and hang them for a bit,less tendenancy for the silicone to puddle on the end of the tire.
Stick em in old axles,and have a bunch to do at one time.
I set a couple old cardboard boxes up,to stick the axles in,then used a hair dyer under the boxes to speed up curing time.:thumbsup:
Try Dow Corning 734 clear if ya can find a local distributor as it is as good as it gets but if not look for a Murphy / O Reilly's auto store and get Versa Chem flowable winshield repair silicone as it is also VERY good stuff. Harbor freight also sells a generic brand that ain't half bad stuff in a white tube w/ red label. Looking forward to the rest of Joe's how to so thanks ahead Joe i love to see what other guys do and i just know your having fun with it .

Bear :wave:
 

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Dug up my old notes from years ago.
I used to mix Dow Corning Flowable and Permentex Flowable together,with an equal part of laquer thinner as a thinner(the laquer thinner is a bitch to mix,i used to spin a tire in the mix with my dremel to mix everything,laquer thinner probably isn't the best thinner median,but it's what i've got lots of,lol).
If you're rebuilding old silly-foams,clean and lightly sand the tire on a sheet of 220 Wet/Dry sandpaper using 99% rubbing alcohol as a lubricant,then clean them using 99% ,before dipping them.
A piece of styrofoam is what i stuck the axles in to hold them after dipping,to hang them the other way,i used old magnets to hold the axles upside down on my steel bench,you want to let them hang each way for roughly 20 min's,helps avoid the puddling effect that will happen if you only hang them one way.
2nd coat i applied after the first coat had cured for at least 20 min's.
I cured them for a couple hours using heat,then let them sit for a few days before using.
Not meaning to butt in on your post,just passing my experiences on for you.
After you've done a few,you'll get you're own technic down,they do take a bit of experimenting to get right:thumbsup:.
BTW.i was always meaning to look into a better thinner median then laquer thinner,but i switched to slip-ons a 1/2 dozen yrs ago,and never pursued it after that,so you might want to search around for something better to use as a thinning agent,straight out of the tube,i always found the flowable to be to thick to work as a dipping agent,but that's me:wave:
You can also use normal old RTV silicone,and use your finger to apply it,some spit on a sheet of glass works to smooth it out
 

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I was told that using thinner like lacquer or any of the others was not the way to go for a durable coating? Was told about Micro-Marks silicone thinner was the ticket?
 

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Your probably right,the laquer was a bitch to mix throughly into the silicone,but i had lots on hand,:thumbsup:.
I did about 500 pairs using this combo of mix,sent about 300 pairs out for guys to try,never had many complaints about the coating's life expectancy,but also never had a proper thinner to compare the coatings too,so you could very well be right,about a better thinner giving a longer life'd coating.
At the time i looked around for a proper thinner,but this was close to 10 yrs ago when i was playing around with coating tires,and there wasn't that much that was easily available for thinners up here in Canuckville
Years ago BSRT (probably 20yrs ago now) used to sell foam donuts in 2 hardness's that you glued to a hub,then trued to size before coating,if they still have any left over,that's your easiest approach to making your own silly-foam tires from scratch
 

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Oh OK Hornet!

I confess....I too have used the RTV and spit method too!

It worked great for baked AFX Specialty and Dragster tires.
 

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Discussion Starter #12 (Edited)
ok class settle down now and open up your mind.thanx to hornet for adding /sharing nice to see an interest in tire makin.we left off with sanding to size.150 grit to get em close then 220 for the final shaping also take a lil off the edge to gie em a lil roundness and the dont catch a rail also they start to look realistic.once the dremmel is secured in the vice and your sure u like the size and shape take the silicone and put some on your finger and rub it in and smear it all around your home spun slicks now just hit the on switch and let it rip. just for a second or 2 ahh first coat done! youll notice the have a rough finish to em but the 2nd coat will make all sins go away.now you need a place to let em dry .i drilled a hole in a bench and insert the mandrell in it. to speed drying time i have a clip light and get it 3 or so inches from mandrell it will cure/dry em quickly.soon youll be ready for coat 2 repeat spreading silicone.this time stand the mandrell on the other end this will let the sillicone migrate to the other side.let them dry. hurry up and wait cuz that chassis is calling for her new skins.i go for 3 coats myself. they look so good you could eat,em.now boys its up to you go ahead and try it ! youll be rewarded with a fine product that u made. ther will be no final exam but i do what to see pics of your good and bad rounds.silifoam tires will and to the enjoyment of slot hobby.as for me i,m heading to a scratchbuilt that i started last winter. thanx for reading this enjoy boyz!!
 

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Bill that's how the first silly-foam came about,some guy showed up at i think it was the Hopra nats somewhere around the mid to late 80's with a homemade foam tire coated with RTV silicon,and things proceeded from there,that's my understanding of the story,but i sure wouldn't want to be quoted on it;).
As far as i know,it was Tony at Slottech who pionered the mass produced dipped silly foam tire as we know it today
JoeG,you'll get a better finish if you look into thinning the flowable then dipping the tire in the mix.I'd check into what Blubyu suggested
The best finishes i used to get,were when i managed to get the flowable silicone thinned almost to a water like mix
 

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I have to confess,but I have been doing my own tires starting this summer for the winter season series (now). Just finished my last batch of .436 on .230x.340 rims and will post pics when they are dry. It's been fun learning the technique. So far they have worked as good as what is out there. But I was waiting for the true test on our banked oval as it tears up the outside tire and I can say the black foam that I was using could not hold up to the rookie who I had driving my loaner. The other colors that were used passed the test. Pics coming. SORRY!
 

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No I'm not dipping them.Don't like to use my fingers either (to messy for me) I spread the first coat on using a scrap pc of plastic rubbing in the first coat real good then spinning it with a plastic cup covering the tire again to keep the mess down.
 

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Just as joegri say's the first coat is just to get it down into the foam and it looks a bit rough but the 2nd & 3rd coats change all that,nice and smooth. He also is right on about the amount of time spinning. I will spin a bit longer when I am trying to final match if one is sizing out taller it gets a second more.
 

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Discussion Starter #19
hey blu and hornet thanx for attending i learned from the both of you . heading to the bench to see what some ascitone will do as a thinner.i,ll check back if i get a positive result.
 
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