MTI hose question

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MTI hose question

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Kacordy	K Kacordy posted 5 Years Ago HOT Topic Details
K Group: Forum Members Posts: 17, Visits: 341	I would like to try MTI hose. Out of curiosity I took a 2 foot section of MTI hose, added an elbow at one end, sealed it with yellow sealant tape, at the open end I wrapped and sealed it with sealant tape, then applied vacuum. The MTI Hose holds at 20 very well. I thought the white covering was supposed to be porous and let the gasses seep through while blocking the resin? I’m I supposed to take a fine needle and poke holes through the membrane to get it to work? Thanks, Allen
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Hanaldo	Hanaldo posted 5 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	+x Kacordy - 9/22/2020 4:35:13 PM I’m I supposed to take a fine needle and poke holes through the membrane to get it to work? Thanks, Allen Certainly not! I'm not sure what youve done wrong here, but something is wrong. Can you post a picture of what you tried? Have a look on YouTube for MTI Hose, DD-Compound themselves and lots of others have some good videos where you can see how to use the hose correctly.
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Kacordy	K Kacordy posted 5 Years Ago HOT Post Details
K Group: Forum Members Posts: 17, Visits: 341	+x Hanaldo - 9/23/2020 12:18:24 AM +x Kacordy - 9/22/2020 4:35:13 PM I’m I supposed to take a fine needle and poke holes through the membrane to get it to work? Thanks, Allen Certainly not! I'm not sure what youve done wrong here, but something is wrong. Can you post a picture of what you tried? Have a look on YouTube for MTI Hose, DD-Compound themselves and lots of others have some good videos where you can see how to use the hose correctly. Check this out. I hooked up vacuum to one end of the MTI hose and plugged the other end. Apply vacuum and the MTI hose is sealed and holds vacuum perfectly. So how is the MTI hose used under the vacuum bag to remove air and draw resin into the mold? Look closely and the white outer liner is wrinkled because the vacuum has drawn the material in. Here is a picture. The white material is not porous. If it was porous it would not hold vacuum. Check out the gauge at 20. Allen
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Lester Populaire	L Lester Populaire posted 5 Years Ago HOT Post Details
L Group: Forum Members Posts: 311, Visits: 13K	+x Kacordy - 9/23/2020 2:45:45 AM +x Hanaldo - 9/23/2020 12:18:24 AM +x Kacordy - 9/22/2020 4:35:13 PM I’m I supposed to take a fine needle and poke holes through the membrane to get it to work? Thanks, Allen Certainly not! I'm not sure what youve done wrong here, but something is wrong. Can you post a picture of what you tried? Have a look on YouTube for MTI Hose, DD-Compound themselves and lots of others have some good videos where you can see how to use the hose correctly. Check this out. I hooked up vacuum to one end of the MTI hose and plugged the other end. Apply vacuum and the MTI hose is sealed and holds vacuum perfectly. So how is the MTI hose used under the vacuum bag to remove air and draw resin into the mold? Look closely and the white outer liner is wrinkled because the vacuum has drawn the material in. Here is a picture. The white material is not porous. If it was porous it would not hold vacuum. Check out the gauge at 20. Allen does it hold this vacuum level when you turn off the pump? there is obviously some restriction with the MTI hose. I usually pull the initial vacuum through the resin feed side to get all the air out quickly. cheers
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Hanaldo	Hanaldo posted 5 Years Ago HOT Post Details
Group: Forum Members Posts: 2.5K, Visits: 28K	+x Kacordy - 9/23/2020 2:45:45 AM The white material is not porous. If it was porous it would not hold vacuum. Check out the gauge at 20. Allen I can not tell from the photo what you are doing, but you are jumping to conclusions here. I can assure you the white material is a semi-permeable membrane, and it works as intended when used properly. Not only have I used it personally, but it is an award winning internationally used product. DD-Compound post on here semi-regularly, so they will probably be along in a bit and reply themselves. In the meantime, this is a very strange test. 20mm/Hg is no where near full vacuum, which indicates that you are pulling against a major air leak - likely the MTI hose. It is very difficult to see any wrinkles in the hose in that photo, but to me that looks like the hose when it is not under vacuum. Watch this video, this is how you use the hose:
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